PART B - MANAGEMENT REPORTS

5. BRAZIL, NORTHERN PINK SHRIMP FISHERY by J.A. Negreiros Aragão, K.C. de Araújo Silva, N.M. Ehrhardt, J.-C. Seijo and D. Die
6. BRAZIL, NORTHERN RED SNAPPER FISHERY by R. Cutrim Souza
7. FRENCH GUIANA, SHRIMP FISHERY by A. Charuau and P.A. Medley
8. FRENCH GUIANA, SNAPPER FISHERY by A. Charuau and P.A. Medley
9. GUYANA, SHRIMP FISHERIES by N.M. Ehrhardt and D. Shepherd
10. GUYANA, GROUNDFISH FISHERIES by N.M. Ehrhardt and D. Shepherd
11. JAMAICA, SHRIMP FISHERIES by I. Jones and P.A Medley
12. SURINAME, GROUNDFISH AND SHRIMP FISHERIES by T. Chin-A-Lin and M. IJspol
13. TRINIDAD AND TOBAGO, SHRIMP AND GROUNDFISH FISHERIES by L. Ferreira and S. Soomai
14. VENEZUELA, SHRIMP AND GROUNDFISH FISHERIES by J.J. Alió

5. BRAZIL, NORTHERN PINK SHRIMP FISHERY by J.A. Negreiros Aragão, K.C. de Araújo Silva, N.M. Ehrhardt, J.-C. Seijo and D. Die

5.1. Introduction
5.2. Stock Assessment
5.3. Fishery Management

5.1. Introduction

The industrial shrimp fishery in north-western Brazil represents the second largest source of income from marine renewable resources in the country, only second to the spiny lobster fishery in north-eastern region. The catch consists of pink shrimp (Penaeus subtilis), white shrimp (P. schmitti) and seabob (Xiphopenaeus kroyeri), with pink shrimp making up the majority of the catch. The fishery is managed by the Brazilian Institute for the Environment and Natural Renewable Resources (IBAMA).

The shrimp fishery in northern Brazil is conducted along the coasts of the States of Amapá, Pará, Maranhão and Piauí by artisanal, small-scale and industrial vessels. However, main fishing grounds are located between the mouth of the Parnaiba River (at the border of the States of Maranhão and Piauí) and the border with French Guiana, hereinafter referred to as the Northern Region.

Fishing operations by the artisanal and small-scale fleets are carried out in estuaries along the coast, mostly catching juvenile shrimps with artisanal fixed gear or hand-operated trawl nets. In the State of Maranhão, small motorized trawlers, with overall length from 7 to 11 m, are commonly used to catch seabob (X. kroyeri) and white shrimp (P. schmitti) on daily trips.

The industrial fleet had about 200 vessels in 1994. Most of these vessels (159) were based in Belém and Macapá in the States of Pará and Amapá, respectively. However, a few industrial vessels were based in Fortaleza and Camocim in the State of Ceará and Parnaíba, State of Piauí. In general, the industrial vessels are Gulf of Mexico-type shrimp trawlers made of steel, 19 to 25 m in overall length. These vessels are powered with 235 to 710 HP main engines and operate with a double-rig shrimp trawl system. Some industrial vessels from Piauí, however, are smaller in size and a few of them operate with single trawls. Over 95% of the shrimp landed by the industrial fleet are pink shrimp, which is almost 100% of the total pink shrimp landings.

The industrial fishing season is from February to October, with a closed season from November to January. The best yields are obtained from February to June, when fishing operations are conducted 24 hours per day, with hauls lasting about 6 hours each. After this period, the operations are concentrated during night hours as the shrimp densities on the main fishing grounds decrease. Toward the end of the season some vessels move to fish in the shallower grounds in the Maranhão area, which appear to be more productive during this time of the year.

5.2. Stock Assessment

5.2.1. Resource Status
5.2.2. Bio-Economic Analysis
5.2.3. Research Recommendations

5.2.1. Resource Status

The first comprehensive stock assessment and fishery management analysis of the pink shrimp resources in the Northern Region has been completed as a result of the FAO/CFRAMP Workshops. The most recent stock assessment is based on a large database of monthly landings by commercial size categories and the weight frequency distribution of shrimp tails within those categories, which before the FAO/CFRAMP Workshops were not available for stock assessment purposes.

Catch trends are the result of stock abundance trends rather than fishing effort trends. The fraction of the stock caught per unit of fishing effort is more dependent on competition between vessels for the available shrimp than of stock abundance.

The overall results are indicative that the P. subtilis stocks in the Northern Region may have been subjected from moderate to full exploitation during the seasons analysed. The fishing mortality rate appears to have been higher during 1983 to 1985, but fell thereafter. During the 1990s, fishing mortality rates appear to have been on the increase, especially among females. However, the maximum fishing mortality has exceeded natural mortality on only a few occasions, which suggests the resource is not too heavily exploited.

In general, the resource abundance is highly variable within and among years, but there is always a conspicuous maximum in May. This pattern may be related to the recruitment season, when a more abundant population is available to the fleet.

Female recruitment shows a distinct maximum in every season, while among males there appear to be a more protracted recruitment season with an increased recruitment toward the later months of the year. Generally, female recruitment levels are 2 to 3 times as large as those observed for males and inter-annual recruitment levels appear to vary more conspicuously among males.

Recruitment appears to be related to rainfall. In some years, recruitment closely follows patterns similar to those of rainfall. It is observed that a relatively greater stability in rainfall and recruitment patterns is observed in the last four years of analysis.

Seasonal abundance varies greatly among years with a significantly lower abundance observed in 1983 for both males and females. In general, stock abundance appears larger during the late 1980s and early 1990s. Because of lower abundance in the late 1990s, the processing plants are having difficulties in securing enough resource to keep operating at normal levels. For this reason, several processing plants have closed their operations in recent years.

5.2.2. Bio-Economic Analysis

Using the best available parameter estimates for the fishery, a bio-economic model was applied to estimate catch and profits considering for the current levels of effort and recruitment.

It was observed that the fleet is operating close to the bio-economic equilibrium at current recruitment levels. This implies that at current levels of biomass and effort, resource rent is being lost. Improvements in resource rent would require limiting access and reducing the number of fishing days. The level of effort that maximised the net present value of the fishery was estimated to be 23000 fishing days.

To aid decision-making with significant uncertainty in future recruitment levels, decision tables were constructed to represent different states of nature for this critical variable. A precautionary “minimax criterion” was applied. It selects the fisheries management decision that minimizes the maximum loss of opportunities (regrets) amongst alternative levels of recruitment. The results suggest a suitably safe option would be to reduce effort to 23 000 fishing days.

5.2.3. Research Recommendations

It is important that information is of the highest quality to ensure accurate advice for management. The current analyses have a number of limitations, which can be addressed through further data collection and research. It is recommended that:

1. Biological data, such as size, sex and maturity, be collected to monitor the biological condition of the shrimp and check whether significant differences can be observed since data were last collected in 1980.

2. Further analyses be developed to include non-equilibrium age-based methods. This will provide a useful contrast to methods applied so far in understanding and predicting the behaviour of the shrimp stock.

3. Further analyses be conducted comparing the current method for estimating biomass production with alternative methods, such as dynamic biomass models. This will help in estimating potential yield and therefore appropriate reference points for decision making.

5.3. Fishery Management

5.3.1. Recommendations

The current fishery management regulations were implemented in the mid-1980s (e.g., closed seasons, closed areas, fleet control) when growth of the fleet had reached peak levels (287 vessels in 1985). In spite of those regulations, the fishery has experienced a significant decreasing trend in landings since 1987 (6,400 tonnes) until 1999 (2,900 tonnes). The decreasing trend is more conspicuous in the late 1990s as a direct consequence of a decrease in recruitment in that period.

The decreased abundance has resulted in the reduction of the fleet size from 230 vessels in 1994 to 134 in 1999. During the same period (1996-1999) the fleet increased the number of days at sea per fishing trip from 29 to 37 in an attempt to keep the landings per trip stable. The catch per day at sea was kept roughly constant at 122.5 kg.

The stocks were exploited (in 1998) at the highest levels of fishing mortality relative to the entire study period. The abundance of the stock decreased considerably from the maximum levels observed from the late 1980s through the early 1990s and recruitment had decreased in the late 1990s. Fishing effort, on the other hand, has remained constant during those years. These conditions are, therefore, indicative of a full exploitation status of the resource.

Over the last ten years, the relative fraction of smaller shrimp in the landings has increased significantly. This may represent a problem of growth overfishing. This issue has generated significant discussion among stakeholders and managers as the value of the landings has decreased. The reason for the increased quantity of smaller shrimp is not known, but increases in fishing costs (e.g. increases in fuel prices) may have resulted in vessels operating closer to shore than in previous years.

5.3.1. Recommendations

Two factors are of fundamental importance to fishery management strategies for this fishery:

• The resource experiences large changes in seasonal recruitment, which is related to seasonal rainfall.
• The fishing power of each vessel (fraction of the stock captured per unit of fishing effort) is affected by the total fishing effort as a result of competition between vessels. The total catch therefore is closely related to shrimp abundance.

Management recommendations emerging from the assessments are:

1. Controls on fishing capacity (number of vessels) should be considered as a precautionary measure. Therefore, the fleet size should not be increased above its current number.

2. A plan of effort reduction should be implemented. The present level of fishing effort is close to the optimum level estimated for the current level of recruitment. Results suggest there may be some increase in profitability of the vessels and lower risks associated with a reduction in effort from the current 24 659 to 23 000 fishing days.

3. A seasonal closure should be implemented that protects new recruits. New estimates of seasonal recruitment suggest that current closed can be improved to obtain a better size distribution of shrimp in the landings.

6. BRAZIL, NORTHERN RED SNAPPER FISHERY by R. Cutrim Souza

6.1. Description of the Fishery
6.2. Problems in the Fishery
6.3. Stock Assessment
6.4. Conclusions
6.5. Recommendations

6.1. Description of the Fishery

History

Red snapper is caught on the coasts of north and northeast of Brazil and constitutes an important fishing resource in these two areas. The industrial fishery started in 1961 using handlines (vertical long lines). Subsequently, a new type of fishing gear (“bicicletas”) that incorporated a manual reel was introduced. Between 1980 and 1992, small boats known locally as caiques were used but these were found to be very dangerous and also led to a reduction in the quality of the fish, as they were kept for long periods without any refrigeration. Recently, starting in approximately 1997, fishing with traps was introduced. At the time of writing, the red snapper fishery was conducted using handlines, longlines, traps and gillnets.

Principal Species caught by Handline

Lima (1976) estimated the relative contributions to the total landings by weight as indicated in Table 6.1.

Table 6.1 Principal species caught by hand lines

English name	Local name	Scientific name	Percentage of landings
Southern red snapper	Pargo ord	Lutjanus purpureus	85.6
Dog snapper	Dentão	Lutjanus jocu
Horse-eye jack	Guraximboira	Caranx latus	5.6
Yellowtail snapper	Guaiuba	Ocyurus chrysurus	4.2
Red grouper	Garoupa	Epinephelus morio	0.9
Grouper	Cherne	Epinephelus novestus*	0.5
Rainbow runner	Arabaiana	Elagatis bipinnulata	0.4
Venezuelan grouper	Serigado	Mycteroperca bonaci	0.3
Cobia	Beijupirá	Rachycentron canadum	0.1
Wahoo	Cavala impinge	Acanthocybium solandri	0.1
Other species			1.9

* Species not found in Cervigón et al., 1993, should it be E. niveatus?

Brito and Furtado (2000) identified 17 species in the trap landings and estimated their relative abundance by number: L. purpureus accounted for 83.2% of landings; Rhomboplitis aurorubens for 8.5%; Balistes vetula for 7.3%; Holocentrus adscencionis for 0.4%; E. morio and Cephalopholis fulva each for 0.3%.

Principal Fishing Area

The total area where catches are made covers 89,164 km² and is divided into three sub-areas:

• Oceanic Grounds found between 32(and 39(W at an average distance of 100 miles from the coast.
• Northeastern Continental Shelf stretching along the coast of the States of Ceará, Maranhao and Piauí, between 39(and 46(W, at an average distance of 50 miles from the coast and at depths between 40 and 140 m.
• Northern Continental Shelf, along the coast of the states of Pará and Amapá between 46(W e 52(W, close to the edge of the shelf.

Principal Landing Sites

The principal landing ports in the north of Brazil are: Belém, Vigia, São João de Pirabas and Bragança.

6.2. Problems in the Fishery

Growth of the Fleet

As no new permits are currently being issued for the snapper fishery, fleet owners are obtaining licenses to fish for other fishes but then use these to fish for snapper. In addition, during the closed season of the lobster fishery, from January to May, there is a migration of lobster vessels into the snapper fishery. These phenomena contribute to an increase in effort in the snapper fishery and are generating conflicts between the fishers who feel threatened by the growth in effort.

Capture of Undersized Fish

The capture of small specimens in this fishery is increasing, potentially compromising recruitment to the spawning stock. The fleet is fishing close to the coast, probably in the snapper feeding areas. Pressure on the smaller fish is also being increased by an increase in the exports of snapper to the United States of America, where small snappers are popular in the market.

The Trap Fishery

With the introduction in 1987 of traps for fishing for snapper, the issues were raised of its relative fishing efficiency and the potential impact on the environment when traps are lost, because they are not made of biodegradable material. Currently there is no legislation covering fishing with traps. As a result, there are conflicts between shipowners, some of whom are concerned that trap fishing may destroy the fishery.

The Lobster Fishery

The fleet of the lobster fishery in northern Brazil is concentrated in the city of Augusto Correia. The fishery utilises extensive lengths of gillnets, which are soaked for long periods of time. Small snappers are a by-catch in this fishery. In addition, because of strong currents, the nets can be carried into the deeper gravel beds, increasing their impact on the food chain.

6.3. Stock Assessment

6.3.1. Growth Rate
6.3.2. Landings

6.3.1. Growth Rate

An attempt was made to use length frequencies obtained from landings between 1997 and 1999 to determine growth parameters using the FISAT routines for modal progression analysis and ELEFAN. However, it was found impossible to obtain reasonable results. The causes may be the selectivity of the gear or be the continuous spawning of these stocks, which means that there were no distinct cohorts. The estimated growth equations from earlier studies are shown in Table 6.2.

Table 6.2 Published results of estimated von Bertalanffy growth equations for red snapper

Year	Equation	L¥	K	Source
1967/78	Lt = 98.9(1-e-0.090t)	98.9	0.009	Menezes and Gesteira,1974
1979/92	Lt = 92.9(1-e-0.103t)	92.9	0.103	Ximenes and Fonteles-Filho,1998

Figure 6.1 Proportion of the sexes in all biological samples taken from landings

Figure 6.2 Proportion of the sexes in the biological samples taken from landings by month

Analysis of Biological Samples

The following results were obtained from biological analyses using data from April 1998 to January 2000.

• Females accounted for 75% of the fish landed over the whole study period (Fig. 6.1); The sex ratio differed substantially from month to month. (Fig.6.2); Females were more abundant in all size classes less than 70cm and the proportion of females tended to increase with smaller size classes (Fig.6.3); The length at first maturity was estimated to be 42.7 cm. (Fig. 6.4);
• There was a high proportion of small, immature fish in the catches. (Fig.6.5);
• Reproductively active individuals are present in the population throughout the year, but there are two reproductive peaks during the year, viz. in October and between December and April. (Fig.6.6).

Figure 6.3 Proportion of the sexes in the biological samples taken from landings by size

Figure 6.4 Proportion of biological samples, which were found to be mature

Figure 6.5 Frequency of samples in each maturity stage broken down by month. A - immature, B - maturing, C - matured, D - spent

Figure 6.6 Sample frequencies in the four maturity stages broken down by month

Figure 6.7 Total catch, effort and CPUE in BIN vessels

Table 6.3 Total landings of snapper in Brazilian States (tonnes)

Year	Ceará	Pará	Piauí	Rio Grande do Norte	Pernambuco	Total
1974	4315	310		127	500	5552
1975	5041	72		104	820	6037
1976	4857	213		253	576	5899
1977	5410	629	349	390	769	7547
1978	5792	585	127	41	201	6746
1979	4078	85	81	173	200	4617
1980	4368	1252	64	233	65	5982
1981	2762	2911	90		33	5796
1982	1637	3246	50		24	4957
1983	1903	2630	148			4681
1995	3166	493				3659
1996	2320	1749				4069
1997	2062	2972				5034

Source: Boletim de Estatística Pesqueira - IBAMA

Figure 6.9 Total catch, effort and CPUE in BPP vessels

6.3.2. Landings

The snapper fishery landings include a high percentage of small fish: 72% in the handline and longline fishery and 63% in the trap fishery. The effort in the fishery increased substantially between 1995 and 1999, from 50 to 86 boats, with an additional 15 boats entering the fishery mainly between January and May, when the lobster fishery is closed. During the same period there has been an increase in landings, mainly by small scale and medium scale boats as well as handline boats (Figs. 6.7, 6.8 and 6.9). The total landings for Pará increased from a slump of 493 tonnes in 1995 to 2 972 t in 1999. The peak landings, in 1977, were 7 547 tonnes for the whole fishing area (Table 6.3).

6.4. Conclusions

• The fishery on the north coast of Brazil operates in an area of high abundance of small individuals which are still sexually immature.
• In the absence of any effective control on the size of the fleet, there has been an increase in fishing effort, leading to an increase in total landings in recent years.
• The available length frequency data have not been adequate to allow an estimate of growth rate.
• The main species landed in the handline and trap fisheries is Lutjanus purpureus.
• The landings are predominantly females.

6.5. Recommendations

• Abolish the allowance for 15% of the landings of snapper to consist of juveniles as this is not effectively enforced and encourages landings of juveniles.
• Reduce the current number of licences for fishing for snapper.
• Abolish the licenses for mixed fisheries/snapper.
• Reduce the effort in the snapper fishery. The estimated current fishing mortality (F) of 0.75 is very high in relation to the estimated F_0.1 value of 0.46.
• Undertake improved studies on the selectivity and fishing efficiency of traps.
• Undertake combined studies of the fisheries on the north and north east coasts of Brazil.
• Improve the existing data collection system.
• Implement and enforce an effective regulation on a minimum size of snapper in the fishery.
• Establish appropriate legislation for the snapper fishery.
• Determine the impact of the lobster fishery on snapper.
• Prohibit lobster vessels from fishing for snapper.

7. FRENCH GUIANA, SHRIMP FISHERY by A. Charuau and P.A. Medley

Executive Summary
7.1. Introduction
7.2. Management Issues

Executive Summary

Current Status

Stock assessment results suggest shrimps overall and Penaeus subtilis (brown shrimp) in particular are not overexploited. The stock of the shrimps has been increasing over the last few years, as the effort has decreased since the early 1980s. Recently (1996-1999) average annual biomass has been at around 10 000 tonnes, over 1/2 of the estimated virgin stock biomass of 15 000-19 000 tonnes. Stock recruitment has been stable since 1989. However, the stocks also appear close to full exploitation.

There are currently 58 licensed boats in the fishery. The European Union (EU) has implemented a constant TAC (Total Allowable Catch, whole weight shrimps) of 4108 tonnes covering all penaeid shrimp species. P. subtilis (brown shrimp) and P. brasiliensis (pink spotted shrimp) make up 90-95% and 9-14% of the total landings respectively. A spatial closure forbids any trawling inside the 20 m isobath, although that closure has not been consistently enforced. Over the last ten years, there has been a decrease in the number of boats and over the last five years a slowly decreasing trend in fishing effort.

The total catch is about 3 800 tonnes per year. The catch-per-day of the shrimp fleet varies during the year, but averages around 230 kg per day. For the period 1990-1999, there has been an increase in the yield per day, probably due to a change in strategy towards catching smaller size categories in shallow waters.

Recommendations

It is recommended that the TAC be lowered from 4 108 tonnes to 3 820 tonnes. While the current TAC is still under the estimated MSY, it is above the precautionary limit (0.9 MSY). Furthermore, the current TAC is not being reached, so the control is not effective. A TAC of 3820 t would prevent catches exceeding their current level.

Analysis indicates that an improved economic yield will be obtained by reducing effort from the current average 16 000 (63 vessels) to 11 000 fishing days (44 vessels). Reducing fishing effort will increase the numbers of larger more highly priced shrimp in the catches. Slightly higher revenues will be obtained at much lower fishing costs with this reduced effort. This recommendation is consistent with a long-term decline in fishing effort being implemented by fishing companies.

Research is required to identify appropriate modifications to trawl operations so that undesirable by-catch is minimised and the shrimp size composition is optimised. Gear technology, seasonal closures or area closures may be used to improve the size composition of the shrimp catches and avoid capture of undesirable species, such as turtles. For example, the shrimp size selectivity problem might be addressed by mesh size regulation. The possible effects on catches of the seasonal closure are relatively well understood, but otherwise research is required to quantify the benefits of the different management measures. This research is required not only to identify the optimal measures, but also to ensure that the long term assessment and monitoring is not compromised by management changes.

Methods for the processing and marketing of by-catch fish are required to improve resource utilisation. Currently, 30 000 tonnes of fish are discarded annually.

7.1. Introduction

The fishery for penaeids shrimps in French Guiana covers, from the seashore to the 60 m isobath, a surface of 24 000 km²_. The shrimp fishery is the country’s most important fishery. It earns around 200 million francs or 30 M$, exceeded only by the satellite launch facility and gold mining.

IFREMER (Institut Français de Recherche pour l’Exploitation de la MER) has carried out scientific research for thirty years. The fishery is a responsibility of the European Union (EU). The skippers have an obligation to complete European logbooks, which creates an excellent data series for monitoring the fishery. After the switch from USA to French vessels at the beginning of the 1990s, the series is consistent, due to the small number of companies, three of them being responsible for 90% of the landings. All landings are made at Cayenne, which facilitates the scientific sampling programme. All processing is carried out at sea.

Shrimps are directly exported to Europe. In French Guiana there is only a small local market for marine products, because the local human population is small (90 000 inhabitants in the 1980s) and their purchasing power is very low. The infrastructures in French Guiana for marketing and/or importing marine products have not been fully developed. Since the US and Japanese fleets were replaced by French vessels, the two main fisheries, penaeids shrimps and snappers, have been managed by the EU.

The stock assessments done in French Guiana started at the beginning of 1980s and covered the two main stocks of shrimps and demersal fishes. With the aim of sustaining rational management of the stocks, trials on regional assessments were made at the request of the EU using the fishery data collected by IFREMER. The main stocks are:

Penaeus subtilis (brown shrimp): Stock assessments have been undertaken and updated at the workshops in Port of Spain (1997), Georgetown (1998), Belém (1999) and Cumaná (2000). Brown shrimp is the dominant shrimp catch in French Guiana. Stock assessments have been carried using catch and effort data collected from 1968 and size composition data from 1989.

Penaeus brasiliensis (pink spotted shrimp): Has not been assessed in French Guiana. The pink spotted shrimp in Guiana is at the end of its migration between the Orinoco and the Amazon and the individuals caught are old; it is not possible to assess only that fraction of the stock.

Xiphopenaeus kroyeri (seabob): Has not been assessed in French Guiana. The seabob catch is insignificant because of the ban on trawling inside the 12-mile limit.

7.2. Management Issues

7.2.1. Stock Assessment
7.2.2. Management Goals
7.2.3. Recommendations

7.2.1. Stock Assessment

The first data on the shrimp fisheries are from the late 1940s and early 1950s. A US fleet was fishing offshore from Brazil to Trinidad for pink spotted shrimp and the larger sized brown shrimps.

As EEZs were established towards the end of 1970s, the US and Japanese fleets were excluded from many countries, so they requested licences for French Guiana waters. From the beginning of the 1980s, the licences were transferred to French vessels. Over the same time, there has also been a constant decrease of the numbers of vessels, from 91 in 1982 to 63 in 1999.

The catch and effort data are reliable from 1978 and size and species composition from 1989. Between 1978 and 1989, P. brasiliensis had not being sorted at sea from the bulk of the catch; the total catches were considered as catches of penaeids shrimps. Since 1989, species and size composition has been estimated through the scientific sampling programme.

The first complete set of assessments (production model and cohort analysis on lengths and on ages) was initiated in 1998 and updated at the 1999 and 2000 workshops. According to the results of the biomass production model, this fishery is exploited around maximum levels as recommended under responsible fishing. The biomass has recovered from heavy exploitation during the 1980s by the US and Japanese fleets and has been increasing over the last few years as effort has decreased (Fig. 7.1).

Figure 7.1 Observed and expected CPUE trends for shrimp catches. CPUE is thought to be proportional to stock abundance. The trend has been upward since 1984, indicating an overall population increase

Current biomass (January 2000) is estimated to be around 10 000 tonnes, with only a very small chance (<1%) that the stock is overexploited (i.e. less than 50% of the virgin stock biomass; see Table 7.1). The 1996-1999 effort levels were around 77% of that estimated to achieve MSY and therefore close to levels that are recommended under “responsible fishing” principles. The estimated catch at 90% of MSY is less than the present TAC of 4108 tonnes established for this fishery. The current TAC has rarely been achieved in recent years, with current catches clustered around the new estimated target TAC of 3820 t. The confidence interval suggests that MSY estimates and thus catch at 90% of MSY are estimated with sufficient precision to be used in updating the TAC.

The estimates of MSY and f_MSY are similar to those obtained previously (Venaille 1984, Stevenson 1981) during the time of the international fishery, which form the basis for the establishment of the present TAC.

The general results from the age-based assessment (Virtual Population Analysis) and tuned length based assessments for brown shrimp (P. subtilis only) confirm the general conclusions of the production model. However, the age-based assessment provides additional information on catch-at-size, which is useful as the price obtained for shrimp increases significantly with size.

There are two main concerns that stock assessments can address: Firstly, that adequate numbers of spawning shrimp remain to provide future recruitment and conserve the stock. Secondly, that the exploitation pattern is optimised to ensure maximum economic return for the fishery.

Table 7.1 Estimates of biomass and catch and effort limits at MSY and precautionary levels

		Estimate	Confidence Interval
			5%	95%
Biomass (t)	Unexploited	16538	15034	19538
	Current	10929	9735	12563
Limits	Catch at MSY (t)	4235	4171	4327
	fMSY (fishing days)	21427	19324	23046
Precautionary	TAC (90% MSY)	3821	3754	3894
	Effort (90% fMSY)	19209	17392	20741

The shrimp biomass does not appear to be overexploited as the current stock biomass is over 50% of its unexploited size. Both current catches and effort are below the levels expected to achieve maximum sustainable yield. MSY is the limit reference point, which should never be exceeded. The confidence intervals indicate relatively accurate estimates for the MSY reference points assuming the model is correct. The precautionary levels of catch and effort allow for errors and unexpected effects (e.g. environmental) on the stock.

In general, both the proportion of the stock that is captured and the stock size vary seasonally. Recruitment occurs throughout the year with a maximum of intensity between August and March. The variations of the monthly biomass follow those of the recruitment.

The trends of the spawning stock biomass (SSB) and recruitment for both males and females, as given by the age-based and the length-based assessments, show that there is no immediate reason for concern about negative effects of fishing upon recruitment levels. Despite the spawning stock biomass showing a slight decrease over much of the period since 1989, recruitment has been stable throughout. The most recent assessment suggests this trend in SSB has halted. These results give no indication that there need be a concern for conservation of the stock.

The selectivity pattern shows that the fleets currently target relatively small shrimp (Fig. 7.2). The selectivity pattern varies during the year, with the lowest catch rates (i.e. fishing power) during April - July.

Catchability (vertical axis in Figure 7.2) is the proportion of the stock caught for each unit of fishing effort. Highest fishing power is shown from September to March. The current selectivity favours catching shrimp 8-13 months old. The value of the catch could be improved by changing the selection pattern towards older shrimp. Improved selectivity for older, larger shrimp could be achieved through closed seasons, closed areas or gear technology. With the exception of closed seasons, there is inadequate scientific information to make recommendations for controls on gear and areas to improve the selection pattern.

Figure 7.2 Example catchability by month and age estimated for females

The exploitation pattern, together with an increase in shrimp value with size suggest that increased returns on the fishery can be obtained by reducing fishing effort (Fig. 7.3). This will increase revenue slightly from the current situation with an effort of 16 000, but more importantly, it will reduce significantly the fishing costs, thus greatly improving profitability. As in all assessments, there is considerable uncertainty. In this case, the growth pattern of shrimp is poorly known. However, testing alternative extreme patterns in growth suggest that while actual long-term returns on fishing can only be poorly estimated, the optimum, target effort remains the same in all cases.

Figure 7.3 Optimum long-term economic yields from the exploitation of shrimp at different constant effort levels for the current exploitation pattern. The results indicate that improved economic yields (i.e. larger shrimp) could be obtained by a reduction of effort to 11 000 fishing days (approximately 44 trawlers). This was tested for three different growth patterns in the stock assessment. All indicated a maximum at the same effort, although they varied in their expected returns

7.2.2. Management Goals

Management decisions are made at regional and European Union levels. The EU policy is to optimise the use of the resource while avoiding large variations in production, which threaten low levels of biomass. More specific policy objectives for this fishery are unavailable.

7.2.3. Recommendations

Precautionary Controls

• Set a new TAC to 3820 t and limit effort to 19 000 fishing days. There is no evidence that conservation objectives are not being achieved. However, to ensure sustained stable catches, a minimum requirement would be to adjust the TAC and maximum effort levels to the precautionary levels identified by the biomass dynamics model (Table 7.1). Given that these effort levels exceed current effort and the proposed TAC is around current catches, this should not be onerous to the fishery.

Target Controls

• A reduction in effort towards a target level of 11 000 fishing days (44 trawlers). For the current exploitation pattern, a reduction in effort will lead to increased numbers of larger shrimp in the catches and corresponding increase in revenue for lower levels of fishing effort. Current effort is around 16 000 days achieved by 63 vessels. Industry should be consulted over this management measure.
• Improve the exploitation pattern by assessing closed seasons, closed areas (e.g. 12 mile limit) and increasing mesh sizes. Scientific advice is only available for closed seasons, which may be too economically onerous for the fishing industry. It is strongly recommended that research be conducted to quantify the impact of an increase in mesh size to 45 mm, an inshore 30m-isobath area closure and other controls prior to their full implementation. Without such research, not only can the benefits not be quantified, but also the changes may invalidate the current assessment and prevent reliable assessments for a number of years until adequate data on the new regime is obtained. A theoretical closure exists for areas of less than 20 m depth, but is not applied when the yield out of that area decreases. There is an opportunity to enforce closed areas as most of the boats are monitored by satellite with the Argos System.
• Improve the exploitation pattern to reduce by-catch and develop processing and marketing of unavoidable fish by-catch. Currently 30 000 tonnes of marine products are discarded annually. As well as shifting selection to larger size categories of shrimp, alternative exploitation patterns should be used to reduce catches of undesirable species (such as turtles) and non-commercial fish species. The development of the processing of the by-catch of fishes is an important aim for this fishery.

8. FRENCH GUIANA, SNAPPER FISHERY by A. Charuau and P.A. Medley

Executive Summary
8.1. Introduction
8.2. Management Issues

Executive Summary

Current Status

In French Guiana, 41 Venezuelan vessels using hand lines, which get licences granted by the European Union (EU), fish red snappers (Lutjanus purpureus). According to the licence agreement, 75% of their catches are landed in Cayenne. The remaining catch is landed on Isla Margarita (Venezuela) where the boats return approximately every quarter. Although in the EU regulation, there is a possibility for using traps, this gear is forbidden by a regional regulation and only hand lines are authorised.

Catches occur mainly on this fossil reef area, where the population is concentrated. The fossil reef between 70 and 120 m depth has an important role in sheltering older fish. The stock here is replenished by a constant migration of small individuals from muddy areas.

In the past, the red snapper was not considered an important species in French Guiana because it is not related to local socio-economic issues. Furthermore, given the amount of effort at that time, it was considered unlikely that hand lines could overexploit the stock or have a major ecological impact. Only two French companies are involved and the Venezuelan fleet does not come under French authority.

However, recent analyses show that the stock is now overfished. Between 1995-1999 the effort and landings increased by 50%. At the same time, the mean fork-length of the fishes decreased from 45 cm to 36 cm and the mean individual gutted weight from 2.1 to 0.9 kg. However, the stock could be rebuilt with an immediate 25-50% decrease of effort.

At a recent meeting in Belém, 1999, representatives of fishermen did not raise any problems. The dramatic decrease in size observed in French Guiana was rather raised by the scientific staff of that region. This suggests that fishermen do not perceive a problem, probably because their catch rates have so far remained stable despite the increase in effort.

Recommendations

• Effort targeting red snapper should be decreased. The maximum number of available licences (41 for Venezuela and 5 for Barbados) has never been used. In 1999, only 25 Venezuelan vessels were licensed. A decrease to a realistic level of 20 authorised boats for 5000 days fishing would be an equitable measure.
• Improved regional co-operation is required in managing the fishery. The problem of overfishing also depends on activities of unauthorised boats, without licences, which are not landing their catch in French Guiana. The activities of these vessels need to be accounted for in assessments and ultimately they need to be brought under management control.

8.1. Introduction

The management area lies between the Maroni River in the west and Oyapock River in the east. The fishery for red snappers covers an area of approximately 26 000 km², between the isobaths of 50 and 120 m. Red snapper is harvested on rocky grounds by a Venezuelan fleet of up to 41 licensed hand liners, from Pampatar and Carupaño. The licenses are issued free by European Union. Under the licence agreement, the skippers have to land and sell 75% of their catches to two processors in French Guiana with whom they have a contract.

When Venezuelan boats return to Isla Margarita, approximately every quarter, they leave French Guiana with the equivalent of 25% of their total annual catch.

The timing of the fishing by Venezuelan fishermen is marked by two events:

• From March to June there is a decrease in monthly effort during the wet season in French Guiana.
• At the end of November to the beginning of December, they return to Margarita, coming back to the fishery the following February.

Figure 8.1 Percentage numbers of Lutjanus purpureus in the range 20 -32 cm (·) and mean fork-length (¾) in landings of the Venezuelan fleet in French Guiana from 1986 to 1998. The estimated numbers of smallest fish in the landings has rapidly increased as the average size has declined

At any given time, the maximum number of licences is never attained and most of the skippers, even if they have a licence in Suriname or Guyana can ask for one in French Guiana. The change can be made by radio and therefore is not onerous.

The main by-catch of the hand line fishery comprises ten species of groupers, which are not landed in Cayenne, various Carangidae, pelagic sharks, which are processed on board (salted and dried) and, seasonally, Scomberomorus (king mackerel).

The activities of shrimp trawlers are an important source of mortality for juvenile red snappers. Preliminary evaluations of the number of juveniles caught during surveys by typical shrimp-trawlers give estimates, as high as 1.5 to 2 million individuals caught by the French Guiana fleet. In addition, the smallest fishes caught by the main hand line snapper fleet are used as bait.

A new fishery exploited by fishermen from La Martinique and La Guadeloupe was initiated in 1996. They operate with pots mainly on muddy grounds. That fishery is also targeting vermilion snapper (Rhomboplites aurorubens) and lane snapper (Lutjanus synagris). For this assessment, it was considered that the activity and the fleet were too small (there was only one part time boat in 1999) to introduce significant trends in the fishery. The observations made during 1999 show that the catch composition is split evenly between R. aurorubens and L. purpureus.

8.2. Management Issues

8.2.1. Stock Assessment

8.2.1. Stock Assessment

Mean sizes (fork-length) of red snapper landings have decreased since 1991 coinciding with an increasing trend in numbers of fish landed (Fig. 8.1). The size of the hooks has remained unchanged, suggesting changes in selectivity are not due to changes in gear.

Figure 8.2 Y/R and SSB/R in kilos for Lutjanus purpureus in French Guiana, from Length Cohort Analysis (top) and Extended Survivors Analysis (bottom)

However, an Extended Survivors Analysis also gave estimates of recruitment, which had increased as fishing pressure had increased (Fig. 8.3). This may be an effect of depletion of the stock in reef areas leading to increased migration of younger fish from muddy grounds. Red snapper cannibalises its young and is territorial, which means that when an adult red snapper is caught, a source of natural mortality for juveniles is directly eliminated and the reef can shelter more young specimens migrating from the muddy grounds. However, there are reasons to suspect that recruitment may not be well estimated by the analysis. In summary, it is possible that effectively recruitment has increased, but the analysis may have tended to overestimate this effect relative to increasing selectivity of younger fish.

Figure 8.3 Fishing mortality and recruitment estimates for Lutjanus purpureus from Extended Survivors Analysis. There was a strong log-linear relationship between recruitment and fishing mortality estimates

The assessments require more scientific research to improve their reliability. The growth parameters remain one of the main sources of uncertainty in these assessments. Other sources of uncertainty are related to the estimation of fishing effort and the annual length compositions of the catches by shrimp trawlers. Finally, the analysis would be enhanced with data on all catches (including discards) some of which are currently unavailable. Improved data would eliminate most of the important concerns with the analysis.

Management Goals

Management decisions are made at regional and European Union levels. The current policy is to provide local landings, while avoiding excessive exploitation, which could lead to overfishing. More specific policy objectives for this fishery are unavailable.

Recommendations

• Set new effort levels of 20 boats for 5000 days fishing. In general, the numbers of young fish has been increasing in the landings. Although at least one analysis suggests recruitment might have increased, this has not yet been confirmed. Both to improve yields and protect the stock from recruitment overfishing, a precautionary reduction in effort is warranted.
• Improve regional co-operation for managing the fishery. Significant catches are taken from this stock, but not reported to French Guiana. Improved monitoring and management can probably only be achieved with greater co-operation with Venezuela, Suriname and Guyana.
• Further research is required on growth and recruitment. As well as specific research programmes on growth and migration, improvements in data collection would produce more reliable analyses allowing improved exploitation of this stock.

9. GUYANA, SHRIMP FISHERIES by N.M. Ehrhardt and D. Shepherd

9.1. Background of the Shrimp Fishery
9.2. Management Issues
9.3. Conclusions
9.4. Recommendations
9.5. References

During the four CFRAMP/FAO Stock Assessment Workshops, 1997 to 2000, assessments were conducted for three species of penaeid shrimp (Penaeus brasiliensis, P. subtilis and P. notialis).

9.1. Background of the Shrimp Fishery

The shrimp fishery is economically and socially the most important fishery in the country. The fishery was formally established when processing plants were built in Georgetown in the early 1960s and fleets landed shrimp in Guyana from fishing operations carried out in the entire region. This international fishery expanded rapidly until 1975. After the region’s adoption of EEZs in 1977, the fishery became a national fishery with a very significant drop in the landings and fishing effort. The amount of fishing effort was further reduced when the 1980s fuel crisis forced the fleet to operate closer to port. At present, the stocks are fully utilised and management actions are required to keep the fishery at a sustained level.

Under a 1996 CFRAMP project, shrimp data collection was initiated in Guyana (Ehrhardt, 1996; Ferreira and Kuruvilla, 1996) to reconstruct length frequency distributions from existing historic landings by commercial size categories. These data are the base for all shrimp stock assessments done at the Department of Fisheries.

Stock assessments of the three most important shrimp species in the Guyana fishery were accomplished in four workshops held in Trinidad and Tobago (1997), Guyana, (1998), Brazil (1999) and Venezuela (2000) and an in-country workshop in 1997 and during the inter-sessional periods between workshops. The assessment activities included organising databases, analyses to understand the recruitment and stock dynamics of each of the species and an analysis of the impact of fishing on the different size or age groups. In the case of brown shrimp (P. subtilis) and pink spotted shrimp (P. brasiliensis), the assessments were done monthly from January of 1981 through December of 1997. Assessments of pink shrimp (P. notialis) were done for the period January 1990 to December 1997. Two stock assessment methods were used in the assessments of the first two species - tuned length cohort analysis (TLCA; Ehrhardt and Legault 1997) and sequential population analysis (SPA). The third species (P. notialis) was analysed following the tuned length cohort analysis procedure only.

9.2. Management Issues

The shrimp fleet consists of 73 shrimp trawlers and 48 seabob/finfish vessels (of which 15 are inoperative). These vessels are mostly of the standard Gulf of Mexico type trawlers and they operate at distances of 40 - 145 km offshore in waters 18 - 91 m deep. They range in length from 19 to 21 m and use jib trawl nets with 4 to 5 cm stretched mesh in the wings and 2.5 to 3.5 cm in the cod-end. Turtle Excluder Devices (TEDs) are mandatory for the entire shrimp trawl fleet. The local fleet is licensed to catch seabob and finfish mainly, but of late, most of the local penaeid shrimp vessels have been focusing on their seabob/finfish activities in the seasons when the penaeid shrimp resources are scarcer. Because there are no restrictions on the access to the different shrimp stocks, trawlers operate without restriction in the shallower areas of the shelf. These activities are carried out over ecologically sensitive habitat that shrimp species inhabit at earlier life stages. There is no information of the environmental impact of such actions, but it is likely to be high considering the intensity of the shrimp trawling operations observed in those areas.

The average total annual production of penaeid shrimp tails was around 2800 t for the period 1980-1985 and 2000 t for the period 1986-1990. In the 1990s, production ranged between 1500 and 1900 t per annum with an average of about 1800 t per annum. This represents an approximate 36% reduction in landings over a period of 10 years. Stock assessment results suggest that the observed decrease in landings is due to a steady decline in the abundance of the three main species of shrimp exploited by the Guyanese fleets. The decrease in abundance is more conspicuous in the case of the pink spotted shrimp (P. brasiliensis) than in the brown and pink shrimp.

The status of exploitation of the stocks indicates that P. subtilis and P. notialis are fully utilised at the present time. Similar assessments of P. brasiliensis indicate very high values for the fishing mortality rates, especially during the 1990s, which may be indicative that this species is presently being overexploited.

The stock assessment analyses showed that the decrease in shrimp abundance is in part due to an excess of exploitation that may be affecting the stock production. However, environmental variables that may affect recruitment also show significant trends. Total annual rainfall recorded in Georgetown decreased by about 77% between 1967 and 1997, which may have influenced recruitment success.

The fishery management goal has been to exploit the shrimp stocks at their maximum potential yield because shrimp exports generate important hard currency revenues for the country and the industry is an important source of employment in Guyana. A limit of 100 vessels is in effect for penaeid shrimp fleet and the Draft Fisheries Management Plan and the National Workshop called for a review of the fishing effort level. Other standard fishery management options to regulate fishing mortality and enhance production of the stocks are not defined for this fishery. That is, neither a minimum size is in effect nor closed seasons have been implemented to protect females during the spawning season.

Care should be taken at regulating fishing effort to avoid excess fishing capacity. This may be achieved through entry limitations. Closed seasons could be used to protect small shrimp at the peak of their abundance to allow them to grow to larger sizes, which may result in higher prices being paid for the products.

9.3. Conclusions

The main shrimp resources in the Guyana fishery are in need of management to secure their longer-term sustainable use, to maximise revenue and employment. This is due to the following:

• Brown and pink shrimp are fully utilized and pink spotted shrimp is overexploited. This is an indication that fishing capacity needs to be managed or controlled to comply with the goals set for the fishery.
• There is a general downward trend in the abundance of P. subtilis, P. notialis and P. brasiliensis. These trends are more conspicuous during the late 1980s and throughout the 1990s. Their cause is probably a combination of sustained environmental changes that have had a negative impact on recruitment and high exploitation rates.
• There is concern of the potential environmental impact of the intense fishing operations on the shrimp habitat. This may be difficult to assess, but evidence from elsewhere suggests that precautionary measures should be undertaken in environmentally sensitive areas of the continental shelf.

9.4. Recommendations

9.4.1. Stock Assessment Recommendations
9.4.2. Fishery Management Recommendations

9.4.1. Stock Assessment Recommendations

• There is a need to complete the P. notialis stock assessments to include the earlier years of the historic database (1981-1989) and to update regularly all stock assessments.
• A regional review of the growth and natural mortality parameters of shrimp species should be carried out. The existing biological database may allow such comparative analysis to improve the statistical quality of the parameters.
• It is recommended that comparisons between the stock assessment methods be undertaken. The methods including environmental variables in the assessments should be expanded. This latter recommendation is particularly important, as shrimp stock recruitment may be an environmentally driven process.
• There is a need to improve the Fisheries Department databases and to include stock assessment results, so that they are available to all users in the Department.
• There is a need to train a larger number of Fishery Officers on the tasks of stock assessment. The minimum critical mass for such activities has not been reached and the government needs the information to support fisheries management.
• The government should secure the necessary funds for two Fishery Officers to participate regularly in regional shrimp workshops. This is particularly important because these workshops represent unique opportunities to improve shrimp stock assessment and management, as well as allowing access to a regional perspective on the status of exploitation of the shrimp resources.

9.4.2. Fishery Management Recommendations

• Special attention needs to be paid to the exploitation trends observed in the fisheries as the fishing mortality rates are at or beyond the levels of full exploitation for all the main shrimp species exploited by the fishery. The stocks are at present fully utilised and any increase in fleet size will just generate fewer landings per vessel, threatening earnings of the existing fleet.
• It is recommended that controls be established on the fishing mortality of smaller shrimp categories in the landings. This will increase revenues from the fishery through greater biomass growth for any level of recruitment. For this purpose, a closure of the fishery at peak juvenile recruitment and/or closure of areas with high density of juveniles should be studied.
• A set of well-defined and well-supported sustainability criteria need to be developed for shrimp fisheries in Guyana. These criteria will help development of sound legislation to protect the fishery from overexploitation and will generate the framework for better fishery management.
• Government should assess the costs of management and the economic rent that should be obtained from the country’s shrimp resources. Subsequently, Government should look at ways to extract management costs and a fair rent from the resource as public income.

9.5. References

Ehrhardt, N.M., 1996. Sampling protocol. Report on First Mission in Preliminary Assessment of Guyana Shrimp Fishery. Sponsored by CFRAMP. Guyana July 7-12, 1996. 9p.

Ehrhardt, N.M. and C.M. Legault, 1997. Crustacean stock assessment techniques incorporating uncertainty. FAO Fish. Rep. No. 544 (Suppl.): 111-131.

Ferreira, L. and S. Kuruvilla. 1996. Report on the training mission in shrimp species identification and biological data collection. Sponsored by CFRAMP. Guyana, September 2-6, 1996. 9p.

10. GUYANA, GROUNDFISH FISHERIES by N.M. Ehrhardt and D. Shepherd

10.1. Introduction
10.2. Management Issues
10.3. Stock Assessment
10.4. Management Goals
10.5. Recommendations

10.1. Introduction

During the four CFRAMP/FAO Stock Assessment Workshops, 1997 to 2000, assessments were conducted for two species of groundfish: bangamary (Macrodon ancylodon) and butterfish (Nebris microps).

The assessments for groundfish conducted over the past four years were as follows:

Per-recruit modelling (FISAT) was carried for:

• Macrodon ancylodon using data from 1996 to 1999
• Nebris microps using data from 1996 to 1999

10.2. Management Issues

The majority of bangamary and butterfish are harvested by three gear types: trawl nets, gillnets and Chinese seines. Random sampling at different sites has been carried out during visits to landing sites three times per week. Length frequency data were collected from unsorted samples at the various landing sites and fish were measured to the nearest centimetre. Catch and effort data were also recorded. These data were suitable for incorporation in the stock assessments for the years 1996 to 1998.

According to the Draft Fisheries Management Plan for Guyana, the issues of importance for management in the groundfish fisheries include:

• Harvesting of juvenile groundfish by Chinese seine gear;
• Direct conflict between fishers operating the different gear types (trawlers fishing nearer inshore resulting in destruction of the gillnets and the Chinese seine gears);
• Declining catches of bangamary in the various fisheries;
• Increased catches of seabob and juvenile bangamary in the Chinese seine.

10.3. Stock Assessment

10.3.1. Multispecies Multigear Per-Recruit Analyses
10.3.2. Single Species Single Gear Per-Recruit Analyses

10.3.1. Multispecies Multigear Per-Recruit Analyses

The per-recruit analysis showed that the trawl and Chinese seine fishers harvested bangamary (M. ancylodon) at ages far below the age at 50% maturity. This situation could lead to a situation where a small increase in fishing effort could cause a relatively large decrease in spawner biomass per recruit (Figure 10.1). The gillnet fishers harvest bangamary above the age at 50% maturity, therefore increasing effort with this gear would result in a smaller decrease in spawner biomass per recruit. The results from these analyses also support the results of analyses on single species indicating that bangamary is currently being over-exploited.

Figure 10.1 Yield-per-recruit and spawner-biomass-per-recruit of bangamary (Macrodon ancylodon) in Guyana with ‘base case’ trawl net, gill net and Chinese/pin seine net fishing. Analyses were conducted using the ‘traditional’ single-species models with the ‘base case’ scenario where M = 1.2 year^-1

10.3.2. Single Species Single Gear Per-Recruit Analyses

The per-recruit model was used with the bangamary (M. ancylodon) and the butterfish (N. microps). An examination of the length frequencies for landings showed that the three major gear types had different selectivity characteristics and it was not possible to set one standard.

Chinese seine and trawl nets are capturing the juveniles of bangamary. These two fisheries are competing for the same stocks resulting in overfishing. The estimates of the fishing mortality, F, for this species indicated that it is being harvested at levels above the target reference points (F_0.1, F_40%SB). This was supported by examination of the Catch Per Unit of Effort (CPUE), which showed a substantial decline between 1996 and 1998 (Figure 10.2), probably indicating a decrease in biomass and possible even recruitment overfishing. This could have serious consequences in the future if not corrected.

The results obtained from catch-curve analyses of length frequencies of butterfish (N. microps) suggested very high fishing mortalities. However, these estimates need to be treated with caution, as they are prone to error. Unfortunately, in contrast to the situation on bangamary, suitable time series of CPUE data are not available for further analysis and comparison with the catch curve results for this species, so no firm conclusions can be drawn on the status of the butterfish resource.

Figure 10.2 Plot of monthly catch per unit of effort (CPUE) for three years (1996-1998) of bangamary (M. ancylodon). A fitted logarithmic trend line is shown, which gives an optimistic estimate of the decline, but still suggests a marked decrease. The final part of the CPUE series (from month 28 onwards) falls below this line and suggests that the decline has been greater than this model suggests

Figure 10.3 Isopleths describing the response of Macrodon ancylodon yield-per-recruit to different combinations of fishing mortality and age-at-50%-selectivity. Analysis was conducted using a single-gear model with the ‘base case’ scenario where M = 1.2 year^-1

10.4. Management Goals

The management goals for the finfish are to:

• Increase landings to a sustainable level;
• Improve nutrition for the population;
• Increase employment and incomes and aggregate output in the form of food stuffs;
• Stimulate growth of the national economy.

10.5. Recommendations

In the case of directed trawling for finfish, a limited entry precautionary approach may be taken, with consideration being given to:

• The restriction of trawling to specified areas designed to reduce conflicts with artisanal fishermen and minimise damage to nursery area habitat and juvenile mortality;
• Mesh size regulations and other gear controls appropriate for trawls targeting fin-fish, so as to reduce the mortality of juveniles, thereby increasing the surviving spawner biomass and potential yield per recruit (see Figure 10.1);
• Adjusting fishing effort to account for by-catch taken in penaeid shrimp and seabob fisheries and giving consideration to the installation of by-catch reduction devices in these fleets.

The bangamary assessments indicate that action needs to be taken to reduce fishing mortality on this species, particularly on the younger individuals.

In the case of the Chinese seine fishery, regulations could focus on limiting the number of licences to those operators already in the fishery while attempting to reduce support for any new licences or renewals of Chinese seine operations. Limits on the numbers of seines per vessel could also be considered. The existing data and models could be used to provide further guidance on the benefits of different degrees of reduction in the different fleets.

In the case of the nylon gillnet fishery, a detailed investigation of the by-catch from this gear is required. If necessary, regulations on mesh size could be introduced and the number of licences issued could be restricted. Later, other limitations on effort could also be considered.

11. JAMAICA, SHRIMP FISHERIES by I. Jones and P.A Medley

11.1. Introduction
11.2. Stock Status
11.3. Management Issues
11.4. Recommendations
11.5. References

11.1. Introduction

The penaeid shrimp fisheries of Jamaica occur mainly in the Kingston Harbour. Depth in this area varies between 10-15 m. Two rivers and several gullies, the major ones being the Rio Cobre River, the Duhaney River and the Sandy Gully influence the Kingston Harbour. The predominant species is the white shrimp Penaeus schmitti, while P. notialis and P. brasiliensis are also present, in very low proportions.

Two fleets exploit the Penaeus schmitti stock. These fleets are of two types. Type 1 are wooden canoes using mono-filament nylon gill nets of 1.4 - 1.9 cm mesh size and Type 2, fibre glass boats that use hand operated trawls of 1.9 cm mesh size. The latter are the only type that utilises an outboard engine (40HP). The fishery is open access and has no current management control in place although the potential for appropriate regulations exist. The fishers involved are predominantly from low-income communities.

In 1994, an estimate of the total landings of P. schmitti was 274 tonnes, although no source is available for this figure. In 1999, the estimate based on the data collection programme was only 4.5 tonnes. It is not thought that the apparent decrease represents a real change in the scale of the fishery, but that it simply indicates a lack of information prior to the current data collection programme. The difference highlights the need for the maintenance of a documented data collection programme in monitoring the status of all fisheries.

For the period 1996 to 1999, several assessments were done at the regional level through a series of regional workshops in which Jamaica participated. The methods were applied to the catch and effort data series currently collected to monitor the fishery.

At these workshops, the key objectives of Jamaica were to:

• Analyse the data available in terms of the status of the P. schmitti stock (Galbraith and Ehrhardt 1999)
• Develop an appropriate method to monitor the fishery and therefore contribute to a management plan for the fishery (Jones and Medley 2000).

A final management plan must be decided after consultation at the national level with the policy makers, stakeholders and scientists.

11.2. Stock Status

The combined assessments for the period 1996-2000 showed that there is no evidence that the fishery is over-exploited (Galbraith and Ehrhardt 1999; Jones and Medley 2000; Fig. 11.1). However, any further expansion of fishing effort should be cautiously implemented.

The assessments were possible due to the successful implementation of the fishery routine data collection programme. However, because the data collection was necessarily limited, results have some uncertainty. Data was mainly available for the China net and trawl gears. Push and shove nets are not well represented in the data collection programme.

The stock assessments that were conducted show some indication of a slight increasing trend in CPUE, predicted as a result of decreased catches in recent years. The trawl gear has been shown to be twice as efficient as the China nets. China nets are approximately 1.2 and 5 times as efficient as shove nets and push nets respectively. Trawl and China nets are also the most expensive gears to purchase.

Figure 11.1 Scaled CPUE indices and 6-month moving average to illustrate population trends. There is no evidence for an overall change in CPUE and therefore there has been no long-term change in stock size. However, recent increases in CPUE are consistent with the recent decrease in catches

11.3. Management Issues

11.3.1. Indicators and Reference Points for the Fishery
11.3.2. Monitoring
11.3.3. Management Control
11.3.4. Pollution and Environmental Factors

11.3.1. Indicators and Reference Points for the Fishery

Indicators measure the state of the fishery. Reference points are used to identify values of the indicator that should guide management or trigger management action. The best indicator at present for shrimp is the annual catch per unit effort (CPUE) and it is suggested this is used as a basis for management of the fishery. Any indicator must be:

• Based on a comprehensive and consistent data collection programme;
• Reliable and have consistent behaviour;
• Related to values of interest to the fishing industry and government, such as sustainability criteria, economic rent and employment.

CPUE is not only indicative of the stock size, but also of the earnings from the fishery. A simple multiplication by the market price gives earnings per day. The higher the CPUE, the healthier the fishery, but if CPUE falls to low levels, a problem is indicated both in terms of earnings and stock size. Monitoring CPUE on a yearly basis will provide useful information for management of the fishery.

11.3.2. Monitoring

For detailed accurate stock assessment, considerably more research and analysis is required. However, not only might this mean that there will be a considerable delay before an assessment is completed, but also the cost of the research programme to provide an adequate scientific assessment may be prohibitive considering the size of the fishery. Therefore an alternative management system was proposed whereby the current data collection system is used to detect significant declines in stock size.

The system chosen was to use the current average CPUE for the last three years (1997-2000) when data has been collected as the base CPUE. We wish to test whether the population has declined in any given year relative to this value. If it has, a recovery programme would be implemented. The current CPUE would be defined as the CPUE of the trawl and Chinese seine fisheries, which are sampled most reliably in the data collection programme. Formally, the test is to see whether the annual average CPUE of each gear separately has declined to some proportion (the reference point) of the base CPUE. The problem is to define an appropriate reference point as the average CPUE can only be estimated and cannot be measured accurately.

There are two errors that management can make. Firstly, a recovery programme could be implemented when none was necessary. That is the average CPUE of both gears have fallen below the reference point even when the population had not declined or had in fact increased. Secondly, management could fail to implement a recovery programme when the stock had declined. That is, the average CPUE of both gears have not fallen below the reference point, when in fact the stock had decreased significantly. Assuming the costs of the two types of error were equal, a reference point of 80% of the current average CPUE was found to be the optimum.

The expected costs can be minimised using an 80% reference point on CPUE. If actual costs became available, or alternative management rules were suggested, they could be developed and tested in the same way. Errors and their associated costs cannot be eliminated, but errors can be reduced through more data collection, which usually itself incurs greater costs. Methods to minimise all these costs combined can be found through analysis and this approach could be taken in future research activities. Cost estimates would have to take into account the views of fishermen and the fishing industry.

11.3.3. Management Control

Greater management control is required to maintain and improve the shrimp fishery. The Jamaican shrimp fishery has a monitoring programme and a successful series of assessments, which, fortunately, indicate that the fishery is probably not in an overexploited state. However, even if overexploitation had been discovered, there is no agreed action that might be taken to deal with the problem. The fishery lacks standardised procedures for monitoring and control of the fishery, which are required for a successful management system.

Management controls could include the following:

• Closed seasons or areas to protect juvenile or spawning shrimp
• Effort control, through, for example, limited entry
• Gear controls to reduce catches of small shrimp

All these systems require administration, enforcement and surveillance. Inexpensive systems need to be developed to allow any future management advice to be translated into management actions.

11.3.4. Pollution and Environmental Factors

Over the last two years, a trend of falling market prices has been observed. It has been reported that the shrimp were discoloured and that hotels and restaurants were switching to imported shrimp. This may also have been the cause for reduced estimated landings in recent years compared when the data collection programme started in 1996.

An assessment of this impact was simulated and the projected loss in earnings generated up until July 2000. Based on extrapolated trends in market price, the loss of revenue due to the price decrease was estimated to be around J$700 000. If we assume the fall in price has also contributed to the fall in landings, it is possible that the potential loss in revenue has been as much as J$4-5 million. These figures suggest that declines in water quality may well have resulted in substantial losses in earnings, profits and foreign exchange.

11.4. Recommendations

• Incorporate the 1998 census in the monitoring system. Currently, these census data are being analysed and will be particularly useful for a review of the data collection programme. This review is very important to the monitoring of the fishery and has a high priority.
• Expand the monitoring programme using low cost data collection and control methods. Emphasis should be placed on improving the licensing and registration of shrimp fishers and vessels. Some consideration should be given to collecting market data. The data collection programme should be regularly reviewed, refined and maintained.
• Develop a management plan. The plan should address environmental concerns and should include, among other things, a system whereby pre-agreed action is taken based upon a CPUE indicator and optimised reference point.
• Consultation with stakeholders. A management plan must be in place and discussed with the stakeholders through national workshops. The plan must incorporate stakeholders’ views.
• Legislation. New legislation may be required for implementing the plans.
• Control of China net and trawler effort. The push nets and shove nets have very little effect on fishing mortality due to their low catchabilities. Furthermore, these fishers are at the lower end of the earnings scale in comparison with China net and trawl net fishers and for social reasons, it may not be a good idea to control them without alternative livelihoods being offered.

11.5. References

Galbraith, A. and N.M. Ehrhardt, 2000. Preliminary assessment of the Jamaican penaeid shrimp fisheries of Kingston Harbour. FAO Fish. Rep. 628: 149-153.

Jones, I. and P.A. Medley 2000. Jamaica shrimp fishery assessment. Paper presented at the Fourth Workshop on the Assessment and Management of the Shrimp and Groundfish Fisheries on the Brazil-Guianas Shelf. 2-13 October 2000, Cumaná, Venezuela.

12. SURINAME, GROUNDFISH AND SHRIMP FISHERIES by T. Chin-A-Lin and M. IJspol

12.1. Introduction
12.2. Management Issues of Penaeid Shrimp
12.3. Management Issues of Seabob
12.4. Management Issues of Demersal Fish
12.5. Other Fishery Related Management Issues and Recommendations
12.6. References

12.1. Introduction

Since 1997, four CFRAMP/FAO stock assessment workshops on the shrimp and groundfish fishery on the Brazil-Guianas shelf have been held. This Managers Report for Suriname is based on the stock assessment results and conclusions of the four workshops, the draft Fisheries Management Plan of Suriname and the recommendations of the national workshop on fisheries management held in June 2000 in Suriname (Charlier 200a; FAO/FISHCODE 2000).

The stock assessments undertaken by Suriname since 1996 included the following species:

Shrimp

• Penaeus subtilis (brown shrimp) in 1997, 1999 and 2000
• Penaeus brasiliensis (pink spotted shrimp; hopper) in 1999 and 2000
• Penaeus schmitti (white shrimp) in 1999
• Xiphopenaeus kroyeri (seabob) in 1999 (description) and 2000

Demersal finfish

• Macrodon ancylodon (whitemouth croaker or dagoetifie) in 1997
• Nebris microps (smalleye croaker or botervis) in 1998
• Cynoscion virescens (green weakfish or kandratiki) in 1999 and 2000
• Lutjanus synagris (lane snapper) in 1999

12.2. Management Issues of Penaeid Shrimp

The shrimp fleet has been operating in Suriname since the 1950s. In recent years, a steady decrease has been noticed in the shrimp catches. According to the results of the workshop held in 1998 in Guyana, this fishery is fully exploited in the entire region and over-capitalized in several countries including Suriname (economic overexploitation). Since the stocks are shared along the continental shelf, it is generally admitted that management decisions should be made at regional rather than at national level.

A reduction of effort should be one of the main management actions in this fishery. In 1999 the Fisheries Department set the number of licenses at 104 (the number of licences was 109 in 1998). In the June 2000 national workshop, the shrimping companies recommended that only 90 licenses be issued (Charlier 2000a; FAO/FISHCODE 2000). This number was not based on scientific assessments. In the year 2000, the number of licences issued was 99. In the national workshop of June 2000, the industry also expressed its concerns regarding the decreasing catches in this fishery. Most felt that the decrease was due to the by-catch of the seabob fishery. However, this was not supported by research, which showed that the proportions of shrimp in the seabob catches are quite low, about 1% of the total landed catch (Chin-A-Lin, Babb and Die, 2000).

With regard to brown shrimp (Penaeus subtilis) research shows that since 1997 the biomass has decreased because of higher levels of fishing mortality and low recruitment. Similar periods of low recruitment and yields have been known before in this fishery, but not for such a long period. Biomass levels remained low in 1999 and no recovery has been observed.

Although the situation of the pink spotted shrimp (P. brasiliensis) stock is not as dramatic as that of the brown shrimp, there has been a decrease in biomass recently and there seems to be a long-term downward trend.

Table 12.1 Landings and exports of penaeid shrimps and number of licensed boats

Year	No. of boats	Catch (tonnes)	Export (tonnes)
1995	101	2,612	2.289
1996	107	2,484	2,282
1997	109	2,354	2,295
1998	109	2,100	1,977
1999	104	Not yet available	2,171

Analyses done since the last workshop in 1999 showed the following new results (Charlier, 2000b and c):

Brown shrimp (P. subtilis) (main shrimp species in Suriname):

• Fishing mortality: the general trend from 1985-1999 is an increasing fishing mortality, particularly marked between 1997-1999. This is in sharp contrast to the conclusion reached at the workshop held in Brazil in 1999 (FAO/WECAFC 2000). Based on a shorter time series (1985-1991 and 1996-1997), it had been commented that no apparent long-term change in the mortality levels could be detected. In 1998 and 1999, the fishing mortality appears to have reached levels similar to the natural mortality. (Fig. 12.1). Note that there was no increase in effort in 1998 and 1999 (Table 12.1).
• Biomass: it is now clear that biomass has decreased in recent years. The estimated biomass was higher in the period 1985-1991 than afterwards and biomass has been consistently decreasing since 1996. Particularly low points occurred in 1997 and 1999. The increase in biomass after the lows from 1998 and 1999 has only been modest (Fig. 12.2).
• Recruitment varies from year to year. No long-term trend is observed in the years until 1996. Recruitment has been very low in the last three years, particularly in 1997 and 1999 (Fig. 12.3).

Figure 12.1 Monthly fishing mortalities, P. subtilis, Suriname, 1985-1999

Figure 12.2 Monthly average biomass, P. subtilis, Suriname, 1985-1999

Figure 12.3 Monthly recruitment, P. subtilis, Suriname, 1985-1999

Pink spotted shrimp (P. brasiliensis) (second shrimp species in Suriname):

• Fishing mortality has perhaps started to slightly increase in 1999
• Biomass: the average biomass seems to have decreased in 1998 and 1999 and the general trend since 1985 is decreasing, but not as strongly as for P. subtilis.
• Recruitment was slightly better at the end of 1999.

Possible causes for problems with the brown shrimp fisheries:

• High fishing mortality caused by increasing fishing power. Nominal effort (number of boats, number of days at sea) has not increased, but the fishing power may have changed. The industry does not think this is the case.
• Increased exploitation of small sizes. The largest recorded trawler landings of small size shrimp have occurred in the last few years.
• Possible impact of other fleets on shrimp stocks. The shrimping companies have suggested that the decrease in the stock size has coincided with the coming into operation of the seabob fleet in the shallow coastal zone, presumably increasing mortality of juvenile brown shrimp. The preliminary results of sampling by the fisheries department on board seabob vessels indicate, however, that the amount of brown shrimp caught by this fleet is negligible. However, more research has to be done.
• Environmental effects, affecting recruitment. Recruitment was very poor in 1997 and 1999, which could be a result of environmental influences. Factors such as rainfall may affect habitats vital for recruitment. No study has been done yet.
• Indirect effects of fishing on the environment may be increasing natural mortality. For example, trawling (or other human activities) may be having a negative effect on the seabed habitat.

Possible causes for problems with the pink spotted brown shrimp fisheries:

• Biomass may be reducing gradually as a result of an excessive level of effort, though nominal fishing effort has not increased, it is expressed in number of vessels and number of trips. Complete data are not obtained in more precise units such as number of days at sea or hours fishing. Moreover, technological advances are likely to have resulted in notable increases in the effective fishing effort.
• Current results do not demonstrate an increase in fishing mortality, but it should be noted that the data on which these calculations are based are less precise than those on brown shrimp. The data from the Japanese fleet, which targets this species, are less complete and had to be partly extrapolated.
• Possible impact of other fleets on shrimp stocks. Since the pink-spotted shrimp resource is considered a shared resource in this region, assessments should also be carried out taking into account data from the different countries involved.
• Environmental factors affecting recruitment and indirect effects of fishing. If they exist, they are probably similar factors to those affecting brown shrimp.

All these causes were discussed with the industry during the national workshop. It was agreed that no single cause could be identified with certainty and that more investigation was necessary. The national workshop recommended research on possible ecological changes in the seabed due to (seabob) trawling especially in the shallow waters. It was also felt that the increased harvest of small shrimp by the shrimp companies themselves probably has an adverse effect and that it should be possible for the industry to try to control this impact.

The draft Fisheries Management Plan recommended the following priorities for investigation:

• To study the mechanisms of recruitment, since it has a great affect on productivity
• Since the problems currently faced by the shrimp fishery are essentially of economic nature, bio-economic modelling is necessary to arrive at a successful management system.

Management Goals

In the case of Suriname, maximisation of the net foreign currency returns receives top priority.

Management Tools

Fishing effort can probably be reduced most efficiently by a reduction of the fleet size. The number of licenses was set at 100 in 1999, with a final target of 90.

Increasing the licence fee would help decrease the fleet by encouraging vessels to leave and would ideally more than compensate the loss of foreign currency.

Although the impact of exploiting small sizes on larger shrimp category production has not been established, a closed season is suggested at the recruitment peak. In general, the exploitation of juvenile individuals should be avoided as it has a greater impact for a given yield. Processing companies can start by giving an incentive for the landing of larger sizes or probably demand a fixed percentage of juveniles in the landings.

This type of measure, besides eventually boosting catches of larger size shrimp a few months later, would prevent trawlers fishing in a period when they would otherwise tend to fish in shallow waters, where small shrimp concentrations first appear.

While not investigated in this series of workshops, depth limits can help pursue a combination of objectives. Objectives include the minimisation of interactions with other (especially small-scale) fleets, a global reduction of the by-catch (since by-catch abundance diminishes with depth) and a reduction of the juveniles of finfish species in the by-catch (since juveniles are most abundant in shallow waters). The depth limits have to be reviewed especially concerning the possible interaction between different fishery types. For the year 2001 the lower depth limit has been set at 15 fathoms (27 m).

12.3. Management Issues of Seabob

An artisanal fishery for seabob has existed in Suriname for many years, while an industrial trawler fleet started operating in 1996. Since the start of the seabob trawl fishery, there have been concerns of possible interactions with shrimp trawling and the artisanal fishery. The main problem mentioned by the other fishery types is that the seabob trawlers operate in the spawning areas of the other shrimp and finfish. The industrial seabob fishery started out with one company owning 10 boats and has grown to 2 companies operating 24 vessels (1999). In the artisanal seabob fishery the number of licenses has been decreasing since 1995 and is still decreasing.

The draft Fisheries Management Plan of 1998 recommended a precautionary approach until the potential of the resource was estimated and the impact of this new fishery on other resources would have been investigated. It therefore recommended that the number of licences should be limited to 15. In spite of this, the number of licenses is now 24. At the last workshop held in June 2000, it became clear that another 6 licenses were to be issued. This decision is now being reconsidered, until more information is known about the impact of the seabob fishery on other resources.

Table 12.2 Number of registered fishing units in seabob fisheries since 1994-July 2000.

	1994	1995	1996	1997	1998	1999	July 2000
Trawlers	-	5	5	18	21	24	24
Artisanal Chinese seine (fuiknet fishery)	357	351	277	291	248	237	250

Source: Fisheries Department Suriname

Priorities for investigation recommended by the draft Fisheries Management Plan are:

• A multi-fleet model should provide the basis for the management of the two fleets engaged in seabob fishing.
• A bio-economic study of the fuiknet fishery would help to understand whether and how traditional management could face old and new problems like fluctuations in yield and the introduction of seabob trawling respectively.
• An investigation of the species’ life history should check whether there is a danger of seabob overexploitation through overfishing in nurseries, etc.
• Monitoring of the species composition of the catch of both fleets should provide the information to establish the extent to which seabob trawling affects other fisheries, particularly the shrimp fisheries.

Research on the seabob fishery shows a fluctuation in the catch throughout the year for both active companies. Catches are higher at the beginning and end of each calendar year. The total catch from both companies increased from 1998 to 1999. With regard to the brown shrimp catch, research has shown that the quantities of P. schmitti and P. subtilis in the catch are insignificant all through the year (Chin-A-Lin, Babb and Die 2000).

A general summary on the seabob fishery was given during the workshop held in 1999 in Brazil (FAO/WECAFC 2000). In the Venezuela workshop in 2000, more attention was given to the analysis of seabob length frequencies. Data available were the male and female length distributions of the catch. Samples were taken on board each month. In the laboratory the carapace length, tail length and sample weight for both males and female were estimated. Also, catch and effort data is available by company and by size category. However, assessments could not be done properly because no suitable morphometric and growth parameters of seabob were at hand. Although trial assessments were used to estimate fishing mortality, no firm conclusions on the status of the stock could be drawn at this stage.

It is recommended:

• To establish a study on morphometric and growth parameters for this species.
• To continue the data collection, based on landing reports and the observers programme.
• To continue a length frequency data collection programme for the artisanal seabob fishery (length frequency data for this fishery is available for the years 1991 and 1992).

Management Goals

• This fishery sustains a large number of families and is also one of the few profitable occupations in some rural areas. Preservation of this source of income and of the living standards of the population involved are important objectives.
• The way fishermen themselves are managing their activities and adjusting effort in accordance with expected net benefits should be seen as a way of optimising economic yield.
• The supply of fresh and dried shrimp as traditional commodities for the local market and export and also as an indispensable contributor to the domestic protein supply should be guaranteed.
• The seabob trawler fleet has suggested MEY as an achievable objective.
• Generation of foreign currency and employment must be taken into account in management. Frozen seabob flesh, produced by the seabob factory, is exported and dried shrimp might have export potential (not yet demonstrated).

Management Tools

• The practical measures available to community-based management include the minimal distance between sets of stakes, the number of stakes (nets) by fisherman, the dimensions of the structure (width and depth of the opening), the admission of new fishermen. This information should be clear in the licences issued.
• When sufficient information has been obtained, regulating the total number of nets in a given area (estuary) could control the fishing effort in estuaries.
• The number of seabob trawlers must be controlled. The number should not be increased from the present 24 until assessments have been undertaken and has demonstrated that the resource can sustain greater effort. It may be necessary to decrease effort.
• While not investigated in these series of workshops, depth limits can be imposed on the trawler fleet (proposed minimum depth 8 fathom or 15m).

12.4. Management Issues of Demersal Fish

Demersal fish in Suriname are split up into four types:

• Large demersal fish (e.g. Cynoscion acoupa, Arius parkeri);
• Small soft-bottom demersal fish (e.g. Macrodon ancylodon, Cynoscion virescens, Nebris microps);
• Small sandy-bottom demersal fish (Lutjanus synagris); and
• Red snapper (Lutjanus purpureus).

For the large demersal fish, no assessments were done; therefore management recommendations cannot be made for these species.

Red snapper (Lutjanus purpureus) was assessed in 1999.

During the workshops held in 1997, 1998 and 1999, Suriname focussed on small soft-bottom demersal fish Macrodon ancylodon (1997), Nebris microps (1998) and Cynoscion virescens (1999). For the species assessed in 1997 and 1998 no further assessments have been made after the workshops. New data were collected, but those have not yet been analysed.

Small soft and sandy bottom demersal resources are close to full exploitation (Charlier 1999; IJspol, 2000). These species also form a high proportion of the by-catch of shrimp fisheries (the catches of shrimp trawlers consist of 30% shrimp and 70% by-catch).

It is recommended that the mortality for these fish species should be decreased and as a priority regulations are needed to reduce their discards as much as possible and to limit the impact of non-selective fishing technologies, particularly on juvenile fish.

In the assessments of 1999, it was estimated that the fishing mortality (F) of Cynoscion virescens was high in the year 1998 (F₁₉₉₈= 2.34; IJspol, 2000). Retaining this level of F will lead to the spawning biomass per recruit (SBR) being reduced to 11.3% of the unexploited level. However, since 1999, the large stern trawlers have not been active and this has resulted in the fishing mortality falling significantly (F₁₉₉₉= 1.50) (IJspol, 2000). The estimated SBR for 1999 is 23.4%. In the year 2000 the trawler fleet exploiting demersal finfish decreased from 13 to 11 trawlers. New vessels have been included in the observers programme recently. Trends for this stock have yet to be determined in relation to changes in effort in 1999 and 2000.

A recommendation that came forward in the national workshop held in June 2000 was to decrease the effort in the red snapper fishery and to treat the mackerel as a separate fishery. The fishery for mackerel is seasonal, while that for red snapper goes on the whole year. At the national workshop, it was recommended that the number of licenses should be 60 for red snapper and 25 for mackerel. These recommendations were not based on a stock assessment. In total, this gives 85 licenses for the year 2001 instead of 134, as in 1999. Also it was recommended that research should be carried out on the impact of the trawl activities of the stern trawlers (“kotters”) on the red snapper fishery. Concerning the small soft bottom demersal fish, a decrease in the lengths for the species Cynoscion virescens in landings was noted and further research was recommended.

The draft Fisheries Management Plan of Suriname recommends the following priorities for investigation:

• The monitoring of the landings, effort, LPUE, trawler fleet species composition, by-catch of the shrimp trawlers and the njawarie fleet should be continued and improved,
• Investigation of the discards by all types of trawlers and by njawaries,
• Economic and socio-economic data on the different fisheries concerned are needed to compare the fleets and estimate MEY.

Management Goals

For the small soft bottom demersal fish species the goal is mainly to supply the domestic market and this is the first objective for the management of this resource. A related objective has been to keep prices down and to guarantee the availability of this affordable protein-rich food. Since a few species started being exported, the generation of foreign currency, though not yet a major objective, may play a significant role in the future if more species are brought successfully to the international market.

For the small, sandy-bottom demersal fish species, the main goal is the generation of foreign currency, since the exploitation of this resource is primarily export-oriented.

Management Tools

For small soft-bottom demersal fish:

The reduction in effort brought about by the exit of the stern trawlers from the fishery has not been evaluated yet, but should have substantially reduced fishing mortality. In the light of the reduction, no other urgent action seems necessary. However, plans should be made for the long term of this fishery. Management options include the following:

• Depth limits and closed areas/seasons by type of gear, mesh size and other restrictions on the gear, prohibition of particular gear(s) if results of investigations so indicate, are the kind of regulations required to reduce wastes and juvenile catch.
• A reduction of the fishing mortality and improvement in yield in the directed fishery can also be obtained by imposing regulations on by-catch reduction such as the installation of by-catch reduction devices.
• A plan is required for the monitoring of the different fleets involved in the exploitation of this resource, including the collection of catch and effort statistics and an observers programme.
• Harmonisation of several fleets’ interests may require primarily the definition of fishing zones. Minimum mesh sizes, eventually closed areas/seasons may help fine-tune the fishery.
• While not investigated in these workshops the present regulation banning trawlers from inshore waters deserves to be enforced. Complaints from artisanal fishers and data from the observers programme show that this regulation is often breached.

For small sandy-bottom demersal fish:

• Management of this resource requires fishing effort control, which, based on the assessment results, should not be allowed to increase. This could be practically accomplished through a restrictive licensing policy.
• Given the importance of gathering information on a developing fishery, priority should be given to data collection from this fleet. An observers programme for data collection on the Venezuelan boats should be initiated.

12.5. Other Fishery Related Management Issues and Recommendations

Processing

According to the rules of the European Union, the concept of Hazard Analysis on Critical Control Points (HACCP) has to be adopted in countries that wish to export to Europe. The law on quality assurance was passed by Parliament in October 2000.

Progress has been made throughout the last years on the implementation of HACCP in the processing companies. Recommended in the national workshop of June 2000 is to negotiate with the EU to obtain more time for implementing HACCP, especially since the investments are high. Also recommended was to set up an investment fund with reasonable loan options.

By-catch of shrimp trawlers

By-catch cannot be avoided in many fisheries. The analysis of data from the observers programme and interviews show that an important part of the by-catch in Suriname shrimp fisheries is still being discarded; in some case all of it is discarded. The reason is the preference to only keep the shrimp on board during a trip, because shrimp trawlers are equipped especially for this purpose. Long trips and the extra employment needed for separating species in the by-catch makes processing by-catch an unattractive business. Most of the by-catch landed is caught and selected during the last days and hauls of the trip, mainly in shallow waters. This part of the catch is sold to vendors by individual crewmembers, mainly at the Central Market in Paramaribo. Accurate by-catch landings data from the shrimp fishery is not available.

To promote landing by-catch, introduction of a rule obliging the landing of a certain percentage of the by-catch after each trip is a possibility. This percentage should be based on the demand/quantity of fish needed for a specific type of processing. Therefore, it is very important to know the composition of the size and species in the by-catch, in relation to their potential use. Monitoring has shown that there are potential commercial species in the by-catch, but information on lengths/sizes is lacking. Not only is this wasteful, but also catching these species as juveniles may have a significant impact on other fisheries. The study also showed that the variance in catch and composition (species/size) at different fishing depths and for different boat types (Japanese/Korean) is large. Processing methods and by-catch reduction call for more research on both the financial and technical feasibility.

Other

Room for increasing effort in fishery should be sought in the development of fisheries for large and small pelagic fish stocks. According to research these resources are still under-exploited. Any exploitation carried out now is considered illegal.

The participants in the national workshop held in June 2000 were stakeholders in fisheries namely: government (Fisheries Department, Trade and Industry, Nature Conservation), fishers, boat owners, managers from fish processing and fishing companies and university scientists. A clear recommendation, which came out of this workshop, is that the dialogue between government and industries should be continued. Similar workshops should be organized on a regular basis in order to discuss the problems in the fisheries sector, to present research outcomes to the stakeholders in fisheries and to collect ideas on management from the stakeholders. The idea is to start a joined consultation on fisheries management, which can be used for updating and monitoring the Fisheries Management Plan. These dialogues should also form the basis for the overall government fisheries policy.

12.6. References

Babb-Echteld, Y., 2000. Report on the follow up of the second seminar on fisheries management in Suriname, Fisheries Department Ministry of Agriculture, Livestock and Fisheries, Paramaribo, Suriname.

Charlier, P., 1999. A draft Fisheries Management Plan for Suriname, Fisheries Department Ministry of Agriculture, Livestock and Fisheries, Paramaribo, Suriname.

Charlier, P., 2000a, Report on the second seminar on fisheries management in Suriname, Fisheries Department Ministry of Agriculture, Livestock and Fisheries, Paramaribo, Suriname. (see also FAO/FISHCODE 2000)

Charlier, P., 2000b, Stock assessment of brown shrimp (Penaeus subtilis) in Suriname. Paper presented at the, CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

Charlier, P., 2000c. Stock assessment of pink-spotted shrimp (Penaeus brasiliensis) in Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

Chin-A-Lin, Th., 1999. By-catch problematiek in de garnaaltrawlerij in Suriname. Verslag van een stage bij de Visserijdienst, periode januari-juni 1998.

Chin-A-Lin, Th., 2000. Executive summary on seabob trawl fishery of Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

Chin-A-Lin Th., 2000. Executive summary on Penaeus trawl fishery of Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

Chin-A-Lin Th., Babb-Echteld Y. and Die D., 2000, Stock assessment of Xiphopenaeus kroyeri (seabob) in Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela

Chin-A-Lin Th. and M. IJspol, 2000. Executive summary on seabob trawl fishery of Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

FAO/FISHCODE, 2000. Report of a national workshop on fisheries management in Suriname and a follow-up meeting, Paramaribo, Suriname, 21 - 22 June and 11 July 2000. Rome, FAO, FAO/FISHCODE Project, GCP/INT/648/NOR: Field Report F-12 (Nl & En). 23p.

FAO/Western Central Atlantic Fishery Commission, 2000. Report of the Third Workshop on the Assessment of Shrimp and Groundfish Fisheries on the Brazil-Guianas shelf. Belém, Brazil, 24 May - 10 June 1999. FAO Fish. Rep. No. 628: 206p.

IJspol M., 2000. Stock assessement of Cynoscion virescens (Kandratikie) in Suriname. Paper presented at the CFRAMP/FAO stock assessment workshop on the shrimp and groundfish fishery on the Guiana- Brazil continental shelf, Cumaná, Venezuela.

13. TRINIDAD AND TOBAGO, SHRIMP AND GROUNDFISH FISHERIES by L. Ferreira and S. Soomai

13.1. Introduction
13.2. Shrimp FISHERIES, Current Status
13.3. Groundfish FisherIES, Current Status
13.4. Management Objectives
13.5. Management Recommendations
13.6. References

13.1. Introduction

Trinidad and Tobago has participated in all four workshops on the Biological and Economic Modelling of the Shrimp Resources of the Guiana-Brazil Shelf organized by FAO and the Western Central Atlantic Fishery Commission (WECAFC) and also since 1997 in the four subsequent Stock Assessment Workshops on the Shrimp and Groundfish Resources of the Brazil-Guianas Shelf organized by FAO and CFRAMP with funding from CIDA, DANIDA and Norway and the support of WECAFC. In the latter Workshops the initial focus was on biological assessments of the shrimp and groundfish fisheries, while in 1999 and 2000 bio-economic analyses were added to address specific management issues regarding the fisheries.

The following management issues are outlined in the Government’s Policy Directions for marine fisheries of Trinidad and Tobago (Fisheries Division and FAO 1994) and/or were highlighted at the National Workshop on Shrimp and Groundfish Fisheries of the Brazil-Guianas shelf held in Couve in May 2000 (Fisheries Division and FAO, 2000; Chakalall and Seijo, 2000).

1. Overfishing (Biological and Economic)

Studies conducted to date, including those completed under the FAO/WECAFC Ad Hoc Working Group on Shrimp and Groundfish Resources in the Brazil-Guianas Shelf, indicate full or over-exploitation of targeted stocks as well as stocks subject to incidental captures (Alió et al. 1999 and 2000; Soomai et al. 2000; Lum Young et al. 1992; Manickchand-Heileman and Kenny 1990). Over-capitalization is also evident in the trawl fishery (Ferreira 1998; Ferreira and Maharaj 1993; Seijo et al. 2000; Soomai and Seijo 2000).

2. Socio-economic importance of the artisanal fisheries

The artisanal fisheries provide stability to rural coastal communities where it is estimated that some 195 fishermen are directly employed in the trawl fishery and 464 fishermen in gillnet and line fisheries. Hence, although over-exploitation must be avoided to foster sustainable sources of food and employment, the socio-economic importance of the artisanal fisheries must be a major consideration in decision-making.

3. Inter-dependence among inshore and offshore shrimp trawl fisheries

The interdependence of fleets due to the sequential nature of the fishery represents a source of conflict and indicates the need to restructure the fishing effort and operations among the fleets to utilize the resources optimally.

4. By-catch issues

Previous studies show that the majority of species captured incidentally by the trawl fleets is discarded (Maharaj 1989; Kuruvilla et al. 2000). A major proportion of the discards comprise juveniles of commercially important species targeted by other gears. This results in conflict among trawlers and other gear users.

5. Regional nature of fisheries resources

Fisheries resources are shared with neighbouring countries. It is thus imperative that assessments are done in collaboration with these countries and that the resources are jointly managed. Some of these issues have been addressed in the assessments of shrimp and groundfish fisheries conducted under the WECAFC Ad Hoc Working Group. These assessments are presented in this document along with recommendations for the management of these fisheries.

13.2. Shrimp FISHERIES, Current Status

13.2.1. Stock Assessment of Shrimp
13.2.2. Economic Performance of the Shrimp Trawl Fleet
13.2.3. Bio-Economic Analysis of the Shrimp Trawl Fishery

The shrimp trawl fishery of Trinidad and Tobago is considered to be one of the country’s more valuable fisheries. The trawl fleet comprises 84 artisanal vessels, 10 semi-industrial and 19 industrial (Chan A Shing, 1999). Five species of penaeid shrimp are of commercial importance, namely Penaeus subtilis, P. notialis, P. schmitti, P. brasiliensis and Xiphopenaeus kroyeri. Figures 13.1 - 13.3 illustrate the shrimp landings, fishing effort and catch per unit of effort by trawler type for 1992 to 1999. Data are not available for the industrial fleet for 1996, 1997 and 1998.

Figure 13.1 Shrimp landings (t) by trawler category 1992-1999. Note that estimates are unavailable for the industrial fleet for 1996-1998

Figure 13.2 Fishing effort (net hours) by trawler category for 1992 to 1999

Figure 13.3 Shrimp catch rate (kg/net hour) by trawler category for 1992 to 1999

13.2.1. Stock Assessment of Shrimp

One of the dominant species exploited by the fleets is Penaeus subtilis (brown shrimp). An assessment of the P. subtilis stock in the Orinoco-Gulf of Paria region was conducted at the 1997 Working Group meeting using landings and trip information for 1973 to 1996 for Trinidad’s artisanal, semi-industrial and industrial trawl fleets and Venezuela’s industrial fleet (Alió et al. 1999). The results of the study indicate that the maximum sustainable yield (MSY) is approximately 1 300 metric tonnes and the fishing effort at which this yield can be obtained (f_MSY) is in the region of 13 000 days-at-sea for both fleets combined. The study suggests that the shrimp resources were over-exploited during the period 1990 to 1993 and recommends that the fishing effort be maintained sufficiently below f_MSY for several years and should not be allowed to increase beyond the 1996 level (i.e. approximately 11 000 days (4 500 for Trinidad and 6 700 for Venezuela). Landings and catch rate should be monitored for evidence of stock rebuilding so that fishing effort can be adjusted accordingly. The need to fill the gaps in the dataset was highlighted, especially in the case of landings and trip information for the industrial fleet of Trinidad.

An assessment was also conducted for the P. subtilis and P. schmitti stock exploited by the Trinidad artisanal fleet in the Orinoco delta of Venezuela for the 1990/1991 fishing season (Lum Young et al. 1992). These results indicated that the shrimp stocks were fully to over-exploited.

13.2.2. Economic Performance of the Shrimp Trawl Fleet

A costs and earnings study was conducted in 1997 for the trawl fishery of Trinidad (Ferreira 1998). The study was based on interviews conducted with nine artisanal, four semi-industrial and five industrial trawler owners. The average vessel revenues, costs and profits for 1997 were estimated for each trawler category. Profits to the owner were estimated at approximately TT$17 500 for an artisanal trawler, TT$16 600 for a semi-industrial and a loss of TT$79 000 for an industrial trawler. Of the vessels surveyed, 33% of the artisanal, 50% of the semi-industrial and 60% of the industrial were found to be operating at a loss. Several indicators of vessel performance were also presented for each of the trawler categories. The results suggest that the small trawlers are more efficient than the large trawlers, such that for every dollar spent in operating the vessel, a dollar is earned by an industrial trawler, TT$1.40 is earned by a semi-industrial and TT$1.60 is earned by an artisanal. The annual return on investment was estimated to be approximately 33% for an artisanal trawler, 6% for a semi-industrial and - 13% for an industrial.

13.2.3. Bio-Economic Analysis of the Shrimp Trawl Fishery

A bio-economic analysis was conducted at the Brazil (1999) and Venezuela (2000) working group meetings. Data from the above economic study and biological data collected from the trawl fishery in Trinidad were used, as well as data on the Venezuelan industrial trawl fishery (Seijo et al. 2000). This analysis covered four shrimp species, namely, P. subtilis (brown shrimp), P. schmitti (white, cock or cork shrimp), P. notialis (pink shrimp) and Xiphopenaeus kroyeri (honey or jinga shrimp). The latter two species are caught in negligible quantities by the Venezuelan fleet and hence data were not included for these species for this fleet. Landings and trip data were available for 1995 to 1998 for Venezuela and 1995 to mid-1996 for Trinidad.

The results indicate that as the fishing effort increases the final biomass of P. subtilis at the end of the four-year period decreases and the probability of the biomass falling below the limit reference point of 0.25 of the virgin biomass (481 tonnes) increases, with the probability being 39% at the current level of effort (8 175 days in industrial fleet units for the Trinidad fleet and 9 348 days for the Venezuelan fleet; Figure 13.4). The optimum effort at which the Maximum Economic Yield of US$46.1 million (US$28.5 million for Venezuela and US$17.6 million for Trinidad) for the shared fishery is attained is estimated to be 5 000 days for the Trinidad fleet and 7 697 days for the Venezuelan fleet (Figure 13.5). The analysis therefore recommends that the fishing effort of both the Trinidad and Venezuelan fleets should not be increased beyond the current level. In addition, the optimum allocation of fishing effort between the two fleets which would yield maximum profits to this shared fishery is 61% of the current effort of the Trinidad fleet and 82% of the current effort of the Venezuelan fleet.

Decision tables for alternative management strategies under varying states of nature were derived from the model. The Net Present Value of the joint Trinidad and Tobago/Venezuela fleet over the four-year period was estimated for three levels of fishing effort (current level, 90% and 80% of current level) at recruitment levels of 120% and 80% of the current level. The most favourable management strategy was found to be 80% of the current level of effort (6 540 days at sea for the Trinidad fleet and 7 478 days at sea for the Venezuelan fleet). This strategy maximizes the minimum net present value and minimizes the loss of opportunity. More importantly, such a reduction in effort would decrease the probability of biomass levels falling below the limit reference point of 15%.

Figure 13.4 Risk of exceeding LRP (0.25 B_max) for P. subtilis. The arrow indicates current effort at 39% probability

Figure 13.5 Present Value of Rent for the Trinidad & Tobago/Venezuela trawl fishery. The arrow indicates current effort

13.3. Groundfish FisherIES, Current Status

13.3.1. Stock Assessment of Groundfish
13.3.2. Economic Performance of Artisanal Fleets Landing Groundfish
13.3.3. Bio-Economic Analysis of Artisanal Groundfish Fishery

Groundfish is predominantly landed as by-catch from the demersal shrimp trawl fleet as well as gillnet and line fisheries, which target the mackerels (Scomberomorus spp) and other coastal pelagic species. The main species of commercial importance in the groundfish fishery are the sciaenids, Micropogonias furnieri (whitemouth croaker) and Cynoscion jamaicensis (Jamaica weakfish) locally known as cro-cro and salmon respectively. These species are generally landed by vessels operating on the west coast (Gulf of Paria) and on the south coast (Columbus Channel) of Trinidad. Apart from trawling, the main gears catching these species are demersal-set monofilament and multifilament gillnets, handlines (banking and a-la-vive) and demersal-set longlines (palangue). From the 1998 census of fishing vessels (Chan A Shing, 1999), it was estimated that there were 464 vessels using gillnets and lines. Figure 13.6 shows the general trend in catch per unit of effort (tonnes per day) for both species over the period 1989-1997.

Figure 13.6. Catch per unit effort for Cynoscion jamaicensis and Micropogonias furnieri. Effort has been standardised against banking gear

13.3.1. Stock Assessment of Groundfish

Stock assessments were conducted at the 1998 and 1999 meetings of the Working Group for the croaker (M. furnieri) and salmon (C. jamaicensis) using catch and effort data obtained from artisanal and semi-industrial trawlers, gillnets, palangue, banking and a-la-vive gear operating in the Gulf of Paria from 1989 to 1997. Results show that the current levels of fishing effort exceed the levels at which Maximum Sustainable Yield (MSY) for both species is obtained (Soomai et al. 2000). This may be attributed to the combined effort of six gear types operating in the Gulf of Paria. The analysis, however, used CPUE for the Trinidad and Tobago artisanal fleet only. Data from the Trinidad and Tobago industrial trawl fleet and other fleets operating in the Gulf of Paria were not available and hence the biomass and fishing mortality values can be considered preliminary.

In the 1999 workshop, a joint analysis was also performed with Venezuela for M. furnieri, which used artisanal and industrial data from both countries (Alió et al. 2000). The assessment used catch and effort data for these six fleets and the Venezuelan industrial and artisanal fleets as well as biological data from the Venezuelan industrial fleet. Results show that the MSY for croaker is 1 500 tonnes and this has generally been exceeded from 1987-1993 and in 1998.

The results of both studies are consistent and it is recommended that the fishing effort does not increase beyond current levels and should be decreased over time. The need to fill the gaps in the data set was highlighted especially in the case of catch and effort information for the industrial fleet of Trinidad. It was therefore recommended that catch and effort data for groundfish be collected from the industrial trawl fleet and a biological sampling programme be implemented for the groundfish species. Data on the size structure of both species would then be available from the trawl, gillnet and line fleets to provide an improved assessment of the current state of the fishery.

13.3.2. Economic Performance of Artisanal Fleets Landing Groundfish

A cost and earnings study was conducted in 2000 for the artisanal gillnet and line fisheries of Trinidad. The study was based on interviews conducted with ten monofilament gillnet operators, four multifilament gillnet, eight banking, four a-la-vive and six palangue operators. The format of the interviews was consistent with that used for the trawl fishery (Ferreira, 1998). The average vessel revenues, costs and profits for 1999 were estimated for each of the gillnet and line fleets and the profitability of the gears were estimated as follows:

Gear	Profit (TT$)	% Operating at a loss
Monofilament gillnet	65 943	20
Multifilament gillnet	5 716	25
Banking	57 552	25
A-la-vive	69 809	0
Palangue	67 313	17

13.3.3. Bio-Economic Analysis of Artisanal Groundfish Fishery

A preliminary bio-economic analysis was performed for the croaker (M. furnieri) and salmon (C. jamaicensis) at the 1999 Working Group meeting based on biological and economic data collected from the artisanal fleets landing groundfish. This analysis was completed at the 2000 workshop (Soomai and Seijo 2000). A multispecies, multigear dynamic bio-economic model was used to examine the performance of the five artisanal fleets over a twenty-year period. The model used observed catch and effort data obtained from the trawl (artisanal and semi-industrial), monofilament gillnet, multi-filament gillnet, handline (banking and à-la-vive) and artisanal longline (palangue) fleets from 1984 to 1997.

This model was used to test several management strategies and to observe the temporal fluctuations in performance variables (e.g. profits, yield, biomass) over a twenty-year simulation (1989-2009), under open access and limited effort conditions. Results showed that in an “Open Access Fishery”, yield and net revenues decrease along with biomass of both species. Initial biomass levels for M. furnieri and C. jamaicensis were estimated at 6 322 and 602 tonnes respectively and forecast to be 198 and 109 tonnes respectively at the end of the twenty-year period. Figure 13.7 shows the performance of the fishery based on rent and the current level is indicated at year 9. Under a “Limited Entry Fishery” fishing effort was fixed for trawling and monofilament gillnets at the level of effort that optimises net present value for the five fleets while the other fleets were allowed to operate under open access. Under limited entry, biomass, yield and rent improve.

Decision tables were constructed to investigate the performance of the fishery, in terms of the net present value and the biomass of M. furnieri, under alternative management options based on combinations of limiting effort of the different fleets or banning certain gears. The catchability for the monofilament gillnets was higher than that of other gears and its removal from the fishery would result in greater net present values of resource rent to society. Under this management decision, however, the biomass of M. furnieri decreases to unfavourably low levels. In order to sustain yields in this multispecies, multigear fishery, it is fundamental that fishing effort is limited or reduced. The recommended management option is however to limit effort for all fleets since this option maximises the minimum final biomass attainable and minimizes the loss of opportunity to the fishery.

Figure 13.7 Rent per unit effort for the groundfish fishery under open access conditions

13.4. Management Objectives

The management strategies ultimately put into place should reflect a compromise of some or all of the following objectives highlighted in the Government’s Policy Directions (Fisheries Division and FAO 1994):

1. Implement efficient and cost-effective fisheries management;

2. Ensure through proper conservation and management, that the fisheries resources are not endangered by overfishing;

3. Ensure that the exploitation of the fisheries resources and the conduct of related activities are consistent with ecological sustainability;

4. Maximize economic efficiency of commercial fisheries;

5. Ensure accountability to the fishing industry and the community at large for fisheries management;

6. Achieve appropriate cost-sharing arrangements among all the beneficiaries of sound fisheries management.

13.5. Management Recommendations

The following recommendations for management of the shrimp and groundfish fisheries are based on the results of the shrimp and groundfish assessments conducted to date:

1) Limit numbers of trawlers with a view to reduction in fleet size.

The 1988 Cabinet decision to place a ceiling on the total numbers of artisanal, semi-industrial and industrial trawlers should be enforced. As proposed in the Management Plan for the Trawl fishery (Fisheries Division and FAO 1992) owners of trawlers should be required to hold entitlements to the fishery and these entitlements should be transferable provided the replacement vessel does not have a greater horsepower or fishing power and provided that the replacement is in keeping with the level of fishing effort approved in the Plan. In addition, as recommended in the bio-economic assessment of the shrimp trawl fishery, the fishing effort should be reduced to 80% of the current level in order to decrease the probability of biomass falling below sustainable levels and increase the economic yield to this fishery.

2) Limit level of fishing effort on groundfish resources.

The combined effort of all fleets impacting on groundfish resources, namely trawl, monofilament and multifilament gillnet, handline (banking and a-la-vive) and palangue, should not be allowed to exceed current levels.

3) Implement a biological data collection programme for the groundfish fishery.

This programme would facilitate the conduct of age-structured biological and bio-economic analyses, which would provide more refined assessments of the status of the fishery.

4) Government support for the shrimp and groundfish data collection programme.

Availability of financial and human resources is critical to the success of the following activities:

• Logbook and observer programmes for the semi-industrial and industrial trawl fleets;
• On-going shrimp biological sampling programme;
• Establishment of the groundfish biological sampling programme;
• Economic data collection from the trawl, gillnet and line fisheries.

5) Stakeholder participation in the management and development of the fishing sector.

This is critical to the successful implementation of any fishery management plan and would be achieved through the formalization of the consultation process between the Government and the fishing industry.

6) Activate the existing 1989 Protocol on Co-operation in Fisheries Research between Trinidad and Tobago and Venezuela.

FAO should be approached to provide technical assistance in the following:

• Harmonization of data collection and analysis methods.
• Joint length-based assessments for shrimp and groundfish species.
• Joint bio-economic analyses by fleet for shrimp and groundfish species.

Bilateral meetings are considered essential in the inter-sessional periods between regional assessment meetings.

7) Continued participation of Trinidad and Tobago in regional assessment working groups.

This is considered essential for sound management of the shared stocks on the Brazil-Guianas shelf.

13.6. References

Alió, J.J., D. Die, L. Ferreira, K. Gooriesingh, S. Kuruvilla, L. Maharaj, L.A. Marcano, I. Ramnarine and A. Richardson-Drakes, 1999. Penaeus subtilis stock within the Orinoco and Gulf of Paria region. FAO Fish Rep. No. 600: 153-167.

Alió, J.J., L. Marcano, S. Soomai, T. Phillips, D. Altuve, R. Alvarez, D. Die and K. Cochrane, 2000. Analysis of industrial trawl and artisanal fisheries of whitemouth croaker (Micropogonias furnieri) of Venezuela and Trinidad and Tobago in the Gulf of Paria and Orinoco River Delta. FAO Fish. Rep. No. 628: 138-148.

Chakalall, B. and J.C. Seijo, 2000. Report of a national workshop on shrimp and groundfish fisheries of the Brazil-Guianas shelf. Couva, Trinidad, 2-3 May, 2000. Rome, FAO, FAO/FISHCODE Project, GCP/INT/648/NOR: Field Report F-8 (En). 22p.

Chan A Shing, C., 1999. Report on the 1998 census of fishing vessels (Trinidad). Fisheries Division, Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago, Fisheries Internal Report No. 3. 42p.

Ferreira, L.A., 1998. Economic analysis of the shrimp trawl fishery of Trinidad and Tobago with management implications. Master of Marine Management Graduate Project, Dalhousie University, Halifax, Nova Scotia. 114p.

Ferreira, L. and L. Maharaj, 1993. Preliminary costs and earnings study of the artisanal shrimp trawlers operating in the “Special Fishing Area” adjacent to the mouth of the Orinoco river (Venezuela). Technical report of the project for the Establishment of Data Collection Systems and Assessment of the Fisheries Resources. FAO/UNDP: TRI/91/001/TR14. Port of Spain, Trinidad: Ministry of Agriculture, Land and Marine Resources. 48p.

Fisheries Division and FAO, 2000. Report on National Workshop on Shrimp and Groundfish fisheries of the Brazil-Guianas Shelf. Rudranath Capildeo Learning Resource Centre, Couva, 2-3 May, 2000. Port of Spain: Trinidad and Tobago.

Fisheries Division Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago and FAO, 1992. Draft management plan for the shrimp trawl fishery of Trinidad and Tobago. Management report of the project for the Establishment of Data Collection Systems and Assessment of the Fisheries Resources FAO/UNDP: TRI/91/001/TR26. Port of Spain, Trinidad: Ministry of Agriculture, Land and Marine Resources. 15p.

Fisheries Division, Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago and FAO, 1994. Policy directions for marine fisheries in Trinidad and Tobago in the 1990s. Project TCP/TRI/2352(A). Port of Spain, Trinidad: Ministry of Agriculture, Land and Marine Resources.119p. (Draft).

Kuruvilla, S., L. Ferreira and S. Soomai, 2000. The trawl fishery of Trinidad and Tobago. Fisheries Information Series No. 9. Port of Spain, Trinidad: Ministry of Agriculture, Land and Marine Resources.

Lum Young, P., L. Ferreira and L. Maharaj, 1992. Stock assessment parameters for five species of Western Atlantic tropical shrimp. Technical Report of the Project for the Establishment of Data Collection Systems and Assessment of the Fisheries Resources”. FAO/UNDP: TRI/91/001. Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago. 43p.

Maharaj, V., 1989. The by-catch in the artisanal shrimp trawl fishery, Gulf of Paria, Trinidad. M.Sc. Thesis:University of Rhode Island, U.S.A. 168p.

Manickchand-Heileman, S.C. and J.S. Kenny, 1990. Reproduction, age and growth of the whitemouth croaker, Micropogonias furnieri (Desmarest 1823) in Trinidad waters. Fish. Bull. 88 (3): 523-529.

Seijo, J.C., L. Ferreira, J. Alió and L. Marcano, 2000. Bio-economics of shrimp fisheries of the Brazil-Guiana Shelf: dealing with seasonality, risk and uncertainty. Paper prepared at the Fourth Workshop on the Shrimp and Groundfish Fisheries on the Brazil-Guianas Shelf, 2-13 October, 2000, Cumaná, Venezuela.

Soomai, S. and J. C. Seijo, 2000. Case study for a technologically interdependent groundfish fishery: the artisanal multi-species, multi-fleet groundfish fishery of Trinidad. Draft Working Group Report prepared at the Fourth FAO/CFRAMP Stock Assessment and Management Workshop on the Shrimp and Groundfish Resources of the Guianas-Brazil Shelf, Cumaná, Venezuela, 2-13 October, 2000.

Soomai, S., N.M. Ehrhardt, K. Cochrane and T. Phillips, 2000. Stock assessment of two sciaenid fisheries in the west coast of Trinidad and Tobago. FAO Fish. Rep. No. 628: 124-137.

14. VENEZUELA, SHRIMP AND GROUNDFISH FISHERIES by J.J. Alió

14.1. Introduction
14.2. Stock Assessment of Shrimps
14.3. Stock Assessment of Fishes
14.4. Bio-economic Analysis of the Trinidad-Tobago and Venezuela Shrimp Fisheries
14.5. Recommendations

14.1. Introduction

Since 1996, FAO has organised a series of regional workshops with the economic support of CFRAMP, CIDA, Denmark (DANIDA) and Norway programmes. These workshops have helped researchers from countries within the Guianas-Brazil shelf to evaluate the main shrimp and groundfish resources of the region, with emphasis on those resources shared by several countries.

Trawling in the Atlantic zone of Venezuela dates to the late sixties, mainly in the Gulf of Paria. It was originally performed by small wooden vessels, adapted for trawling, with financial support from the MAC-PNUD-FAO programme. Industrial trawling in the Atlantic zone was initiated in mid-1973, with the migration of Florida type trawlers from the Gulf of Venezuela, establishing their base port in Güiria. Currently, trawling for shrimp and fish in the area is performed by three groups of fishermen:

• Artisans, about 1200 fishermen who operate 250 nets while walking in shallow coastal areas in the northern Gulf of Paria, from Irapa to Soro;
• Artisanal trawlers, about 30 wooden vessels, 8-12 m in length, propelled by outboard engines and operated by crews of 3 sailors, fishing in the Northern Orinoco River delta, with base port Pedernales; and
• Industrial Florida type trawlers, 111 vessels, 17-32 m in length, 100-850 HP, operated by crews of 8 sailors, fishing in the southern Gulf of Paria and the entire Orinoco River delta, with base ports in Güiria, Cumaná and Guanta.

The fishing grounds in the Atlantic side of Venezuela encompass 71 000 km², of which 9 700 km² are located within the Gulf of Paria, from Mouth of Drago in the north to Serpents Mouth in the south and 61 300 km² in front of the Orinoco River delta.

Twenty five fish species or groups of species and four shrimp species are exploited in the area; however, few species of fish (croakers: Macrodon ancylodon, Micropogonias furnieri, Cynoscion virescens and catfishes: Arius parkeri and Cathorops spixii) and two shrimp species (brown shrimp, Penaeus subtilis and white shrimp, Penaeus schmitti) account for more than 90% of the landings.

The catch per unit of effort (CPUE) of white shrimp and most fish resources shows a seasonal trend, increasing during the rainy season in the second quarter. During this time, the decrease in salinity of the water near the coastal zones induces migratory movements of fish and white shrimp towards deeper and more saline waters, where the trawlers traditionally operate. This makes them more available for capture. The brown shrimp regularly occupies deeper areas and shows less variable CPUE during the year.

Management issues in the area include:

• Are the fisheries in the area currently sustainable?
• To what degree are shrimp and fish resources shared?
• What is the interaction between the Trinidad-Tobago and Venezuela fleets exploiting shared fishery resources?
• Can the level of fishing effort of trawlers be increased in any areas, allowing an effort reduction in other fishing grounds?
• What is the impact of the fleet of trawlers upon the resources exploited by artisanal fishers and how can it be reduced?
• What is the impact of artisanal shrimp fisheries upon the resources exploited by the industrial fleet?
• How do environmental parameters affect the shrimp fisheries in the area?
• What are the biological and fishery parameters characterising the main fish and shrimp species exploited in the area?

Some of these questions were addressed in the series of workshops and others remain to be evaluated.

14.2. Stock Assessment of Shrimps

Shrimp fisheries in the Venezuelan Atlantic zone comprise four species, Penaeus subtilis, P. brasiliensis, Penaeus schmitti and Xiphopenaeus kroyeri. Landings of P. subtilis during 1999 represented 56% of total landings (1055 t); those of P. schmitti amounted to 25%, X. kroyeri to 19%, while the landings of P. brasiliensis accounted to less than 2%.

Figure 14.1 Trends of the landings, effort and CPUE of P. subtilis exploited in the Gulf of Paria and Orinoco delta by the fleets of Trinidad and Tobago and Venezuela.

Joint assessments of data from Trinidad-Tobago and Venezuela fleets exploiting the stock of the brown shrimp, Penaeus subtilis, indicate that the MSY for this species is around 1300 t which should be reached at an effort level of 13 000 days-at-sea (Fig. 14.1). A precautionary reference point approach would suggest effort should not exceed 90% of f_MSY, hence a maximum effort level of 11 700 d-a-s should be applied for this species. The allocation of effort between the two country’s’ fleets should be agreed upon.

The white shrimp, P. schmitti, is captured on an occasional basis by the industrial vessels, when the resource becomes available on the fishing grounds during the rainy season. Their landings in 1999 reached 262 t, whereas the landings of artisanal fishermen, those using trawl gears and walking gear, reached 140 t. Sizes exploited by artisan fishers are juvenile shrimp, while those exploited by the industrial fleet are mature shrimp. The CPUE trend is variable and not well defined (Fig. 14.2), suggesting that the impact of fishing on the population of P. schmitti is still limited. This prevents the estimation of the optimum level of exploitation for this stock, but a limited increase of effort could be allowed provided the effect of this increase is properly monitored.

Figure 14.2 CPUE time series of the Venezuelan fishery of P. schmitti in the Gulf of Paria and Orinoco River delta

Since the industrial fleet has lately oriented its effort towards specific fishing areas, where fish, shrimp or both resources are abundant, effort should be recorded according to the fishing zone of operation. This would allow the estimation of the actual impact of the fishery upon each of the resources. This process could be accomplished using landings reports or logbooks.

By-catch of no commercial value represents a major environmental impact of the trawl fishery in the area and the use of Turtle Excluder Devices (TED) to allow the escape of turtles from the nets induce significant losses of commercial catch to the fleets. Technological solutions are available for these problems, like the use of fish nets for the daylight period, when no shrimps are captured; the use of larger mesh size in the shrimp nets; the installation of escape panels for small fish in the codend of the shrimp trawls; and modification of the TED structure.

14.3. Stock Assessment of Fishes

Macrodon ancylodon

The largest landings from the Venezuelan fleet of trawlers are reported for M. ancylodon, which represents 60% of total fish landings (9021 t in 1999). This species is mainly captured in the delta region, where it is more abundant than in the Gulf of Paria. The industrial fleet has increased the landings of this species since 1986, as a consequence of its increasing use in fillet processing plants. Assessments of the stock indicated that:

The level of effort considered adequate for the exploitation of this species (4 600 d-a-s) in the Gulf of Paria and Orinoco delta region, is far below the fishing effort that has been applied in later years (8 000-13 000 d-a-s), as well as the one considered appropriate for the exploitation of the brown shrimp, Penaeus subtilis (14 000 d-a-s). This situation may lead to a severe depletion of this stock, with major impacts on the value of the groundfish fishery. The stable CPUE for this species (Fig. 14.3) may result from a lack of standardization of the effort in the fleet. This species is mainly landed by stern trawlers operating in the Orinoco delta, which are larger than the Florida type vessels. However, the effort from the latter and from the stern trawlers is being lumped together, hence this species may be more heavily exploited than the current evaluation indicates.

Figure 14.3 Observed CPUE time series of the three most important fish species landed by the Venezuelan industrial trawl fishery in the Gulf of Paria and Orinoco River delta

Micropogonias furnieri

The estimated Maximum Sustainable Yield of the species in the region is about 1500 t (1300 to 1600 t). This level of exploitation was surpassed several times between 1987 and 1993 and a subsequent decline was recorded in the landings of all fleets of the region (Fig. 14.3). The reduction of the effort after 1993, followed by landings below the MSY level observed in the fishery until 1996, may explain the recuperation in stock numbers as observed in the landings after this year. The MSY was surpassed again in 1998, when approximately 1800 t were landed. If the increasing trend in effort continues, another decline in the landings can be expected in the near future. It is suggested that effort should not be allowed to increase beyond current levels of exploitation and further, it is recommended that the level of effort should be maintained below that observed in 1997. The open access management strategy that has been typically applied to artisanal fisheries in the past, should therefore be replaced by a limited effort regime, if future declines in the fisheries are to be avoided

Lutjanus purpureus in Foreign Waters

The number of Venezuelan vessels targeting red snapper in the region is about 240 boats (all larger than 14 m long), which make about 15 trips per year. The estimated regional landings by this fleet are about 4400 t per year. The statistics on snapper in Venezuela include whole weight, when the fish are captured in the Caribbean Sea and gutted weight for fish captured in foreign waters. This mistake must be corrected in the national statistics and convert gutted weight to total weight by multiplying by 1.105.

Considering the number of Venezuelan fishing vessels operating in the region and the evaluations performed in French Guiana, it seems that the current effort level is above the one that is recommended for a sustainable fishery. The information available on the biology of the species and catch and effort by the Venezuelan fleet operating in foreign waters 1997-1999, is too short to apply mathematical models allowing the estimation of management parameters of this stock. Yields per country show similar values in Guyana and Suriname (about 1800 kg per trip), which are lower than the ones observed in French Guiana (3000 kg per trip).

Due to the social and economic importance of this fishery in Venezuela and its political impact in the region, an improved stock assessment programme is recommended. It should include the record of fishing activities in log books, interviews with captains while landing in harbours of the eastern region of Venezuela and exchange of catch and effort information with fishery authorities in other countries of the region.

Lutjanus synagris

The resource exploited by the trawling fleet in the Gulf of Venezuela seems to be over-exploited both by the artisanal fleet and by the fleet of industrial trawlers. Considering that the trawl fleet in the area is too large and that several species have already disappeared from the landings, it is recommended that effort should decrease by at least 25% (a reduction of 43 industrial vessels from the current number of 170) if the sustainability of the fishery is to be achieved.

The resource exploited by artisanal fishermen and the trawl fleet in the Gulf of Paria seems to be fully to over-exploited. Landings of each fishing sector seem similar (50-150 t per year). It is recommended that the current effort (180 artisanal vessels and 111 industrial vessels) be reduced by an equal proportion.

14.4. Bio-economic Analysis of the Trinidad-Tobago and Venezuela Shrimp Fisheries

A preliminary bio-economic analysis revealed that the fishing effort of both the Trinidad-Tobago and Venezuela fleets should not be increased beyond the current level. In addition, the optimum allocation of fishing effort between the two fleets, which would yield maximum profits to this shared fishery, is 61% of the current effort of the Trinidad fleet and 82% of the current effort of the Venezuelan fleet.

Since effort quotas are allocated in Venezuela to the fleets operating in each fishing ground on an annual basis, decision tables were prepared to help administrators in the effort allocation process, to estimate impacts of variation in recruitment.

14.5. Recommendations

• Effort levels in most fisheries of the area are considered excessive and should be lowered to allow sustainability of these fisheries. Only the fishery of white shrimp may be able to accept a moderate increase in fishing effort.
• An intensive programme to record reliable catch and effort information must be implemented in all landing harbours. The assessment of stocks requires basic information, like records of catches and their composition, fishing effort, sizes of fish captured and landed. It also requires some other information associated to the biology of the species, like mathematical models to describe the growth, the length-weight relationship, natural mortality rate, etc. Among them all, information on catch and effort is the most critical. Only some fisheries in Venezuela (like tuna fisheries) have recorded reliable information on catch and effort. Most other fisheries, in particular the shrimp and groundfish fisheries, have had severe problems obtaining these basic data on fleet operations.