D. J. Agnewa, C. P. Nolanb and J. Pompertc
a Renewable Resources Assessment Group, T. H. Huxley School of Environment, Earth Sciences and Engineering, Imperial College, 8 Prince's Gardens, London SW7 INA; b Fisheries Consultant, 124 Ennafort Rd, Raheny, Dublin 5; c Fisheries Department, Falkland Islands Government, Stanley, Falkland Islands.
Most demersal fisheries around the world include catches of skates and rays (Rajidae). Despite their ubiquity, a generally low interest in assessing and managing rajid stocks has resulted in published assessments of rajid fisheries (Anderson and Teshima 1990). At the same time, it is acknowledged that elasmobranch life histories imply them to be generally K-selected1 species (Hoenig and Gruber 1990), and amongst this group sharks are especially vulnerable to stock collapse under relatively low fishing pressures (Anderson 1990). The generally low fecundity and late maturity which typifies rajid species, combined with their relatively sedentary behaviour (Steven 1936), would indicate that they are particularly sensitive to fishing pressure and over exploitation (Walker and Hislop 1998). In acknowledging these characteristics, the Falkland Islands Government has implemented rigorous management and control of its rajid fishery.
Where directed skate and ray fisheries exist, the majority are prosecuted on mixed species assemblages (Teshima and Wilderbuer 1990, Fahy 1991, Martin and Zorzi 1993). It is more common, however, in the majority of global demersal fisheries, for rajids to be taken as a commercially profitable bycatch (Ishihara 1990). Both types of fishery operate around the Falkland Islands. Rajids occur in mixed species assemblages and are caught by both a directed fishery and as bycatch in other fisheries. Even within the directed fishery, although some species are valued more highly than others, fishermen are not able to target these species to the exclusion of others. Therefore in common with other rajid fisheries (Fahy 1989, 1991) the Falkland Island stocks are managed as a mixed species assemblage.
This review presents information on the practices adopted and implemented by the Falkland Islands Government in the management of its rajid fisheries.
2. THE FISHERY
2.1 Fishery development
2.1.1 Historical development
Rajid catches around the Falkland Islands have been recorded since the establishment of the Falkland Islands Interim Conservation and management Zone (FICZ) in 1987 (Figure 1). Catches during the 1980s were taken primarily as a part of a general mixed demersal fishery by Spanish vessels and were less than 1500t/yr. However, in 1989 a Korean fleet entered the fishery specifically targeting rajids and by 1991 annual catches had risen to over 7000t with a number of different fleets taking part. Catches peaked in 1993 at 8523t. Management controls on the directed skate and ray fishery in the form of specific licences were first introduced in August 1994, and since then the rajid catch has declined primarily in response to the reduction in directed effort. As a conservation measure based on management advice, directed fishing for skates and rays was prohibited south of the Falkland Islands in 1996. The trawl fishery therefore is currently restricted to waters north of the Islands.
1 K-selected species have low natural morality, low growth rates and produce few young per breeding cycle.
In December 1990 the Falklands Outer Conservation and Management Zone (FOCZ) was established, extending to 200nm from coastal baselines (FIG 1997) (Figure 1). Although this area is too deep for conventional trawling, licenced longlining targeting Patagonian toothfish is undertaken and takes a small bycatch of rajids.
There are two seasons to the Falkland Island fishing year, the first season running from January to June and the second from July to December.
Distribution of rajid catches in the Falkland Islands fishery expressed as a graduated plot
The size of circle is proportional to log(catch) and the largest size is equal to 3200t. The 100, 200, 500, 1500 and 3000m isobaths are shown. Boundaries of the Falkland Islands Interim Conservation and Management Zone and the Falklands Outer Conservation Zone are shown. The area closed to directed rajid fishing in 1996 was that south of 51°S.
2.1.2 Harvesting methods
The directed fishery is prosecuted by factory freezer vessels using demersal trawls. The general distribution of catches reflects that of the effort that is expended (Figure 1). There are two main areas of the rajid fishery; to the north of the Falkland Islands, situated over the shelf break, and immediately south of the Falkland Islands where an indentation of the shelf produces an area of particular attraction to large species associated with cold-water and shelf slope areas.
According to Korean fishermen, the longer nosed Raja flavirostris and Bathyraja scaphiops, refered to in Korean as ‘Hongu’, have a better taste and command a better price than the other rajids known as ‘Kaori’. However, the mixed nature of the rajid assemblage over the shelf prevents single species targeting.
2.1.3 Catch history
Prior to the introduction of a directed skate and ray licence in 1994, rajids were caught under the terms of mixed finfish licences by a variety of vessel types (Figure 2). Rajids were also reported as bycatch in other fisheries, in particular the bottom trawl fishery for the squid species Loligo gahi (see Agnew et al. 1998) and the general finfish fishery. Currently there is some indication that bycatches of rajids in these fisheries may be lower from vessels which in targeting demérsal and semi-demersal fish species have modified or replaced the footropes and bobbins of their ground gear and incorporated a high lift net opening into their trawl configuration.
Total catch of rajids (t) by licence type reported from the Falkland Islands' fishery from 1987 to 1997
The small discrepancy between the totals in this figure and those in Figure 3 in 1996 is due to catches by experimental longline vessels.
The high level of fishing in the early 1990s was associated with the discovery of a ‘ray hot-spot’ south of the Falkland Islands, where a large part of the catch was concentrated. Since fishing in this area was prohibited in 1996 fishing effort has been restricted to the area over the shelf break to the north and north east of the Islands. Vessels prosecuting the fishery have always preferred to target rajids in this area during the second half of the year particularly during the period from late winter through to early spring. Part of the reason for this is that the trawlers tend to engage in the high seas Illex fishery (for which they need not purchase a licence) during the first half of the year. As a result of these spatial fleet restrictions and a general reduction in catches in recent years the concentration of effort of the fleet has become more pronounced (Figure 1).
There is a small deep-water longline fishery for Patagonian toothfish operating experimentally in Falkland waters. This fishery catches a small number of rajids in deeper water within the FOCZ to the south east and north east of the Falkland Islands. In 1996 this fishery also operated close to the shelf break in the north. The Loligo fishery, in which some rajids are taken, is located to the south and east of the Islands.
2.1.4 Fleet characteristics
The Korean fleet began to target rajids under a general finfish licence in 1989. The total skate and ray catch increased rapidly in 1991 partly due to expansion of the Korean fleet, but also due to catches taken by Spanish vessels and Korean vessels operating under the Honduran and Panamanian flags (Figure 3). Since the introduction of a specific skate and ray licence in 1994 the majority of the reported rajid catch has been attributed to vessels fishing using this type of licence.
Vessels operating in the rajid fishery are generally between 50 to 60m in overall length, between 350 and 1300 GRT and 2200–2600 BHP and are typically crewed by a compliment of 30–35.
The total catch of rajids (t) reported by vessels of all trawl licence types operating in the Falkland Islands’ fishery from 1987 to 1997.
2.2 Species composition, distribution and bycatch
Although Korean vessels have dominated the skate and ray fishery since its inception in 1994 the south-east Asian economic crises of late 1997 and 1998 have had an adverse effect on the demand for ray licences with companies declining licences due to financial problems. Interest in this fishery is expected to return once the south east Asian economies and demand for these fish products recovers.
The Falkland Islands’ rajid fishery exploits a mixed species assembledge (Table 1). The four most common species are Bathyraja griseocauda, B. albomaculata, B brachyurops and Raja flavirostris. Rajids are not identified to a species level in the daily catch reports as vessel operators are not required to do so. However, on most vessles certain species and sizes are packaged separately as they command different market values. An extensive scientific observer programme collects data on species composition and records the biological parameters of exploited rajids. The species composition of all rajid catches in 1994, and their distribution, is presented in Figure 4.
Two further species have been recorded in catches on trawlers, but only very rarely: Raja leptocauda and Raja trachyderma. In the longline fishery, which operates at depths greater than 600m a further 5 species have been recorded: Raja georgiana, Bathyraja meridionalis and B. papilionifera and occasionally Raja taaf. Disc width is approximately 70% of total length.
|Species||Maximum recorded size (disc width, cm)||Species||Maximum recorded size (disc width, cm)|
|Bathyraja griseocauda||118||Raja doellojuradoi||47|
|Bathyraja albomaculata||53||Bathyraja macloviana||58|
|Bathyraja brachyurops||87||Bathyraja sp.1||90|
|Raja flavirotris||120||Psammobatis spp.2||42|
|Bathyraja multispinus||98||Bathyraja magellanica||54|
1 Bathyraja sp. has been recognised as being a distinct species following analysis of morphological andmeristic details. This data is presently being prepared for publication.
2 The genus Psammobatis consists of some & species (McEachran 1982) present in the Southwest Atlantic.At least three of these have so far been identified within Falkland waters.
The proportion of the rajid catch, composed of the four most important commercial skate and ray species and their distribution, reported by all vessels around the Falkland Islands in 1994
The small, ubiquitous rajid, B. albomaculata has a general distribution over the continental shelf and along the shelf edge to the northeast of the Falkland Islands. The larger R.. lavirostris is generally more prevalent to the west of the Islands on the continental shelf whilst the largest species. B. griseocauda, appears to be associated with cooler, deeper waters on the steep slopes of the continental shelf break particularly to the south of the Islands. Analysis of scientific observer data from all vessel types operating in the Falkland Islands fishery from 1993 to 1995 confirms this general distribution pattern (Table 2).
Agnew et al. (in prep.) have shown that the largest species, with the oldest age at maturity (8–12 years), have undergone some changes during the course of the fishery. The proportion of B. griseocauda has declined in catches in all areas, and the mean length at capture of R. flavirostris has also decresed. These changes are consistent with fishing effort being at levels which cannot be sustained by the stocks of these species. This in turn is a consequence of adopting management measures which allow a sustainable catch of the general ray assemblage, which is itself made up of a number of species with dirrerent resiliences to fishing pressure and mortality.
The most common rajid species caught in the deep-water, longline fishery for the Patagonian toothfish are Raja georgiana, Bathyraja meridionalis, B Papilionifera, Bathyraja sp. and B. multispinis. Occasionally, B. scaphiops and R. doellojuradoi are also reported. Catches of species by area in this fishery vary considerably, however; the majority of rajids are reported from the sourthern part of the FOCZ.
A number of fish species ar taken as bycatch in the directed rajid fidhery. Those of commercial importance include hoki (macruronus magellanicus), southern blue whiting (Micromesistius australis), red cod (salilota australis), kingklip (genypterus blacodes) and bake (Merluccius spp). The total bycatch, which includes these and a variety of non-commercial species, constitites a small but appreciable proportion of the total catch (<20% by weight).
The various operating in this fishery are generally foreign to the Falkland Islands, and consequently details of their operating costs and profitability are not readily available. The main fleet fishing for rajids has been Korean, and they ship their catch directly to Korea via reefer transport from the Faklkland. All except the largest rajids are frozen whole. Of specimens heavier than 15kg generally only the wings are taken as bycatch by vessels operating in other fisheries are winged, skinned and graded prior to freezing in 10–12kg blocks. The majority of this product is sold on Spanish and UK markets.
3. MANAGEMENT OBJECTIVES
As with all fisheries in the Falklands, the primary objective of the Falkland Islands Government is the conservation of resources to ensure sustainable fisheries through effective management of fishing effort (FIG 1997). This is particularly important to the Falkland Islands government due to the large proportion of government income that is generated by fisheries (about half of overall government income comes from selling fishing licences; see Section 9). The Islands, with a population of 2200 (FIG 1996) have a government structure based around elected Councillors and an Executive Council which has a direct say in agreeing to management measures to meet these objectives, such as the level of fees to charge for licences. The process of management is described in more detail below.
4. MANAGEMENT POLICIES
4.1 Policies adopted
Since the Falkland Islands skate and ray fishery is a foreign access fishery, the Falkland Islands Fisheries Department has absolute control over access to the fishery. The fishery is managed by limiting fishing effort, which is controlled at such a level as to maintain the long-term viability of the fishery.
Although the ray fishery is currently managed within sustainable limits, large unsustainable catches of rajids were taken in the early 1990s. This was principally because no management system existed directly related to the skate and ray ray fishery during this period; rajids were taken on a general finfish licence. As skate and ray catches under finfish licences increased and catch-per-unit-effort declined it became apparent that some management specifically controlling the expanding skate and ray fishery would be necessary. Although some declines in catch-per-unit-effort were seen from 1990 to 1991 it was not until 1993 that large drops in CPUE, especially in the ‘hot-spot’ to the south of the Islands, were seen (Tingley et al. 1994) After this, management was swift to act on scientific advice, first introducing licences and then closing the southern area in the face of of continuing declines in CPUE (Agnew et al. 1996).
4.2 Resource access
Prior to the introduction of a directed rajid licence there were few restrictions on access to the general area of the fishery under the finfish licence provisions. However, under the skate and ray licence conditions, and subsequent to the closure of the rajid fishing grounds to the south of the Islands in 1996, the fishery is now restricted to the area north of 51°S (Figure 1). Further, in the second season there is a small extension of this prohibited zone to 50° 30’S between longitudes 56° 30’W and 58° W to exclude skate and ray vessels from the Loligo gahi fishing grounds.
4.3 Gear restrictions
A minimum cod end mesh size of 90mm is currently in force for all finfish fisheries around the Falkland Islands. Cod end mesh sizes used by the Korean skate and ray fleet are a mixture of 90, 100 and 110mm.
4.4 Vessel regulations
Licence fees for vessels fishing rajids are related to their size - larger vessels (measured by GRT, and expected to have a higher fishing efficiency) pay a higher fee than smaller vessels. There is no limit on vessel size.
4.5 Biological regulations
Vessels fishing under general finfish licences are prohibited from targeting rajids, although a small bycatch, which is usually unavoidable, is allowed. Any vessel fishing within Falkland Islands waters can be required to accommodate a scientific observer for a period of approximately one month. In the majority of instances vessel captains and owners comply with such requests and facilitate visits in accordance with their licence conditions.
4.6 Catch/quota allocation
The Falkland ray fishery is managed by controlling the amount of fishing effort that is permitted. The total effort allowed in the fishery is determined from assessments of stock status and calculations of the effect of various levels of effort on the stock. The effort that each vessel is likely to exert, given details furnished on its licence applications, is calculated and only a limited number of vessels are granted a licence to ensure that the total allowable effort is not exceeded. This calculation takes into account the size of the vessel, the duration of the licence (available in monthly units) and the past fishing history of that type of vessel. Each vessel is then free to fish to the extent that it deems appropriate, and is not constrained by catch quotas. This method of effort allocation is scientifically quite intensive, but it reduces the temptation to misreport catch and effort statistics.
5. MANAGEMENT PLANNING PROCESS
5.1 Provision of advice
The fisheries year is divided into two seasons, from 1 January to 30 June and from 1 July to 31 December. Even though most fishing for rays has been in the second half of the year (see Section 2.1) in order to manage the fishery effectively skate and ray licences and regulations are issued for both seasons.
Fisheries and scientific observer data collected by the Falklands Fisheries Department are analysed by scientists working at Imperial College. Scientific advice on management is provided by this group to the Falkland Islands Government which sets management targets in line with the scientific advice. Conservation of stocks is the primary aim of fisheries management so there is never pressure from the Falkland Islands government to increase the number of licenses over the limit of the total allowable effort (The Times 1998). Fisheries management advice is provided for both the first and second seasons of the year. Thus advice is developed on a six-monthly basis. This enables a fast response time to fishery developments.
5.2 Fishery statistics
5.2.1 Collection of catch and effort data
All licensed vessels are legally required to provide daily catch and effort details to the Falkland Islands Fisheries Department. Information collected in this manner must specify position, date, amount of fishing effort, catch by species and fishing depth. In addition, a fishing logbook must be completed daily which included provision for details of the amount of product processed and the types of products that are produced (e.g. whole, headed and gutted, headed, gutted and tailed, fillet, wings, roe, meal, cheeks, etc.) as well as the conversion factors used to calculate whole weight from the weight of the processed product. With the exception of the longline fishery for the patagonian toothfish the logbook is general and used in all other Falkland Islands' fisheries. Further, data are required on the discard of non-commercial species or discarded amounts of commercial species.
Vessel operators are not required to report details on an individual skate and ray species basis, but must group these under a general species code for the group. When entering, or leaving, the fishing zone and prior to transhipment procedures, the vessel is legally bound to provide catch and product summaries. All data provided are subjected to checking procedures and are used when vessels are boarded at sea by inspectors and during transhipment inspections.
5.2.2 Collection of biological data
The two primary objectives in the collection of biological data by scientific observers onboard skate and ray vessels are to quantify the catch composition by species and to obtain detailed data on the individual species.
Logistically, it is only possible for one biologist to sample from two or three trawls in a 24 hour period though the vessel may make five separate tows. Quantifying catch composition by species involves counting all individuals in each species per trawl and estimating their weight. The objective when collecting biological data it to collect size frequency data from one or more rajid species per trawl. Due to the Korean market requirements for whole specimens, it is often not possible to obtain maturity data on the female specimens. In this case maturity data is collected from males only as these can be assessed using the relative length of the claspers.
5.2.3 Data validation, processing, storage and availability
All data provided to the Fisheries Department are entered into a fisheries database. All daily catch data, entry and exit catch summary reports and transhipment reports are verified against the data provided in monthly logbooks and against checks conducted by Fishery Protection Officers. The database uses SQL Server with Dataease as a front end. The same database is implemented at Imperial College using Oracle for server software with MS-Access as a front end. MS-Access is used to produce the annual data reports, and distribution plots are produced in MapInfo.
5.3 Stock assessment
5.3.1 Past history
Directed fishing on rajids started in 1991 and reached a peak in 1993. Immediately after the first year of high catches, in 1991, scientific observers started collecting detailed data on the skate and ray catches. However, it was not until early 1994 that an assessment of rajids could be attempted. This took the form of a general production model with constant recrutment (Tingley et al. 1995, Holden et al. 1995) fitted to trends in catch-per-unit-effort. Refinements to this methodology have been made over a number of years and assessments now use the GLM-standardised CPUE separated for areas north and south of the islands. Other production models, such as the Schaeffer model, have also been used (Agnew et al. in prep.).
These assessments have proved sufficient for management of the complex of species that make up the ’skate and ray stock‘. However, it is recognised that the different species within this complex have responded in different ways to fishing pressures exerted on them over the last 8 years. Agnew et al. (in prep.) showed that there has been a decrease in the occurrence of B. griseocauda and an increase in B. albomaculata and B. brachyurops in catches. The maximum size of R. flavirostris has also decreased over this time period. Therefore, there is a need to develop more detailed, possibly age-structured, models of the populations. To this end Gallagher and Nolan (in prep) have been investigating new approaches to age determination of the most important commercial rajids in this fishery.
5.3.2 Measures of stock abundance
The only measures of stock abundance that have been possible to date are CPUE series. Because directed skate and ray licences were only introduced in 1994, and those vessels targeting rajids also obtain general finfish licences at other times of the year, catches from targeted rajids fishing must be identified by their species composition (i.e. the proportion of rays in the catch is used to assess if the vessel targeted rays).
Agnew et al. (in prep) used a natural mortality rate of 0.2 in assessments, calculated using Pauly's (1980) model and average growth parameters for similar species from the Northeast Atlantic. We have no firm knowledge about a specific spawning period for these species; it is likely that recruitment to the adult stock appears to take place year-round.
GLM-standardised CPUE series for the northern area together with catches are shown in Figure 5. It can be seen that the CPUE dropped markedly during the period of uncontrolled fishing and was brought under control with the introduction of licences. The catch during 1994 and 1995 was still too high for the stock, and following the reduction to about 3000t, has shown some signs of recovery.
CPUE and catches from the northern area (±se)
GLM standardised CPUE is calculated for a consistent sub-set of Korean vessels and is therefore only available from 1990.
The CPUE series for the southern part of the fishery showed a continuous decline until the fishery was closed in 1996. The extent of recovery of this portion of the stock since 1996 is unknown since data from a directed fishery are unavailable.
The different behaviour of the CPUE series for the areas north and south of the islands and the different species composition in both areas has lead to the consideration of the north and south areas as separate management regions, but the extent of population mixing between the different areas for the various species involved is unknown. Thus, the complex of species in each area is treated as a separate sub-stock for management purposes.
5.3.3 Biological advice review process
Biological resource management advice to the Falklands Fisheries Department is provided by the Renewable Resources Assessment Group, Imperial College, London. This advice is based on assessments developed using data collected by the Falkland Islands Fisheries Department, both as part of the reporting requirements from the fishery, and by scientific observers on fishing vessels. Some collaborative research is undertaken between Fisheries Department and Imperial College scientists and this, together with field research projects and independent research programmes undertaken by Fisheries Department scientists, provides further data for the development of assessment methodologies and management advice.
Although there is no formal review process, the provision of advice to the Falkland Islands government from Imperial College allows Fisheries Department scientists, and in particular the Director of Fisheries, to review the scientific advice befor adopting it. It thus separates the body providing scientific advice from the body taking management decisions.
5.3.4 Biological management reference points
Conservation is the highest priority for the Falkland Islands government. Thus, long term sustanability and long term yield is the ultimate goal. Estimates of replacement yields are available from the production models described in Section 5.3. Further, and more usually, long term yield estimates have been calculated using the estimates of unexploited biomass arising from the assessments and generic methods such as Beddington and Cooke (1983) and Kirkwood et al. (1994). Notice has also been taken of the theoretical calculations made by Brander (1981) and Walker and Hislop (1998). Regulation of the fishery within these general yield estimates has resulted in catch stabilisation, and even recently in increases in CPUE (Figure 5). Both the directed catch of skate and rays and the expected bycatch in other fisheries is considered when setting management targets for the directed fishery based on the calculated sustainable yield.
Estimates of long-term yield from the northern and southern fisheries indicate that catches, at about the general level of those taken in the last few years, are sustainable from the northern area. Only low catches would be sustainable from the southern area, principally due to the different species structure in this area. The concerns about the rapidly declining CPUE in the southern area, and calculations of a possible sustainable yield being low, lead to a closure of this fishing area from 1996.
Sustainability for the fishery as a whole does not translate to sustainability for each species. As noted, over the course of the fishery there has been an increase in the abundance in catches of the small-sized B. albomaculata and a decrease of the long-lived B. griseocauda. These changes confirm expectations based on theoretical considerations of the link between age at maturity and sustainable fishing pressure (Walker and Hislop 1998).
6. FISHERY MANAGEMENT REGULATIONS
6.1 Regulations applying to the exploitation of rajids
The relevant regulations applying to the rajidae are discribed in Section 4 above. At present, there are a number of different licences that are issued by the Falkland Islands Fisheries Department. A closed area and mesh restrictions apply to all types of licence and the fishery runs for both first and second seasons. Regulations applying to finfish are as follows:
Restricted finfish: valid for capture of all species of finfish with the exception of hake. Rajidae, and toothfish. This licence is principally used for fishing southern blue whiting, hoki and red cod.
Finfish: valid for capture of all finfish species except Rajidae and Patagonian toothfish. This licence allows catches of hake to be taken.
Skate: valid for capture of species of Rajidae (Skate) only. A closed area and mesh restrictions apply to this type of licence. The fishery runs for both first and second seasons.
Longline/toothfish experimental licence: valid for capture of Patagonian toothfish only. All fishing areas with depths greater than 600m are subject to this type of licence.
6.2 Regulations and the communication process
Regulations applying to the fisheries, including the licence application process and licence conditions, are published under the Falkland Islands (Conservation and Management) Ordinance 1986 as specific orders relating to fishing licences each year. For instance, second season licence applications for 1997 were published under the Fishing Licences (Applications and Fees) Regulations Order 1997 (S.R. & No. 2 of 1997), entitled “Application for Fishing Licence - Second Season 1997”.
7. THE LAW AND ENFORCEMENT
7.1 Legal status
The ordinances referred to in Section 6.2, and their subsidiary orders are legal documents, and prosecutions of infractions of them (such as illegal bycatch levels or fishing in a closed area) can be, and are, brought in the Falkland Islands' Court.
7.2 Enforcement problems
The most important enforcement problem relating to the rajid fishery are illegal catches by vessels equipped to target rajids, but operating under the terms of a restricted finfish licence, rather than a rajid licence. In years where demand for rajid licences has exceeded the number of available licences, unsuccessful applicants have often taken out restricted finfish licences as their second choice. Even successful vessel operators have been forced to restrict their possession of a rajid licence to a limited number of months, taking up restrict finfish licences outside these months. These finfish licence types do not restricted access to rajid fishing grounds or the type or dimensions of the ground gear used. In some cases this has resulted in a mixed fleet, of vessels licensed to fish rajids, and vessels licensed to fish other species, both fishing over the known rajid grounds and both capable of targeting rays. The difficulties of enforcement lie in determining whether the daily catch reports of suspect vessels operating alongside legitimate rajid licence holders are correct and whether the ‘bycatch’ of rajids reported by these vessels is below the 10% limit specified under the licence terms for vessels targeting finfish on finfish-specific licence type.
When consistently high bycatches of rajids are reported by vessels equipped to target rajids, but without the required licence type, the vessel is boarded and initially requested to move from the area. In some instances vessels with consistent bycatch problems are also issued a written warning by Fishery Protection Officers, following an inspection of the vesel and her paperwork, at sea or in port. Persistent offenders, or vessels which have clearly been targeting rajids without the authority of the appropriate licence, are likely to be detained. They will be escorted to Stanley for further investigation and possibly prosecution if the circumstances of the case merit such action. There have been a number of such prosecutions.
Scientific Observers are regularly placed on vessels holding rajid licence types and those under suspicion of misreporting rajid bycatch. With no restrictions on minimum size, biological reports show that all sizes of commercial rajid species are taken. Size restricted retention of commercial species remains dependent on the overall catch rate of large and medium sized individuals. In some areas and seasons where catches have been poor all individuals of commercial species have been retained and processed. This has included the smallest hatchlings which are retained whole.
There is constant surveillance of the rajid fishery using a variety of direct and indirect methods. The fishery is routinely monitored by aerial surveillance using dedicated Britten Norman Islander aircraft and this is complimented by inspection of vessels within the fishery by Fishery Protection Officers stationed aboard civilian-operated fishery patrol vessels. Both methods of surveillance are operated year round. The analysis of daily positional and catch reports on shore assists the direction of sea and airborne surveillance.
The costs of surveillance of this fishery are small when considered in the context of the entire fishery and the licence revenue generated therefrom (see Section 10). All means of surveillance are applied to the entire fishery and in consequence the cost of surveillance is a function of annual vessel numbers in the fishery rather than being fishery specific.
Problems relating to the surveillance of the rajid fishery are similar to those experienced in fisheries on other regions where onboard observation of catches and vessel reporting procedures are intermittent. The nature of the entire Falkland Islands fishery dictates that aircraft and patrol vessels must be mobile and attentive to all areas, particularly those where fish stocks straddle international boundaries. Although this results in surveillance resources being widespread throughout the entire area of jurisdiction it retains a certain element of surprise when surveillance of the rajid fishery is executed. Experience in this and other Falkland Island fisheries has shown that while there are some circumstances where misreporting of catches takes place, management through control of effort significantly decreases the incentive for misreporting.
Identification of the possibility of mis-reporting often involves collaboration between the surveillance and scientific functions of the Fisheries Department. Regular analyses of daily radio reports of catches in real time may detect irregularities that may be subsequently investigated by fishery officers. For instance, the catches of ‘hoki’ declared by the “Amapola 515” were first identified as unusual by such monitoring, initiating investigation by fishery officers. This serves to illustrate both the integrated nature of the scientific and protection infrastructure in the Falkland Islands and the rapidity of reaction when required.
7.4 The legal process
In addition to the provisions of the Falkland Islands Fisheries (Management and Conservation) Ordinance and subsidiary legislation, all vessels operating within Falkland Island' waters are also subject to terms and conditions applicable to the licence type held by the vessel. Licences are vessel specific. The captain, owners and/or charterers hold responsibility for compliance with fisheries legislation and licence conditions.
Upon arrest by Fisheries Protection Officers on suspicion of an offence against the fisheries legislation, the vessel is detained and the evidence is submitted to the Attorney General, who will decide whether a prosecution should be brought. If a prosecution is justified, the case is tried through Stanley Magistrates Court, where the Senior Magistrate will determine culpability. If a conviction is secured, monetary fines are generally the penalty inflicted on the captain and owners of the vessel. In certain circumstances, the vessel's catch and/or fishing gear may be ordered forfeited.
Two recent cases involving illegal fishing for rajids illustrates enforcement in this fishery. The first involved the Amapola 515, a Korean owned vessel registered in Panama. She held a restricted finfish licence to fish in Falkland Islands waters. When inspected by fisheries protection officers, the holds were found to contain nearly all blocks of frozen ray. From the daily radio reports, it was apparent that the ray had been reported as hoki.
The case was heard in the Stanley Magistrates Court on 26 July 1995. Because of the amount of ray onboard and the lack of any other species, it was decided to charge the master and owners with fishing without a licence (an offense which carries a maximum penalty £250 000). The company was fined £70 000 and the master £800 on two counts, for fishing without a licence and misreporting his catch. In addition, the catch of approximately 85t of ray was ordered to be forfeited and was subsequently sold back to the company for approximately £38 000.
The second case involved the Korean registered Tae Chang 85. This vessel held a restricted finfish licence for the period 1 September to 30 November 1996. On 1 and 2 December 1996, the vessel transshipped its catch in Berkeley Sound and inspection by fishery officers revealed that in excess of 40% of the catch transshipped consisted of ray. Two log books were found onboard, one consisting of the catch figures used for radio/FIFD logbook reports and another giving the true figures for ray caught in zone each day. The master eventually admitted falsifying his catch reports.
The master and owners were initially charged with fishing without a licence, but the charges were amended to a breach of licence conditions following representations from the owners' legal advisers. On 7 February 1997, the maximum fine of £25 000 was imposed on the owners and the master was fined £600 on two counts of breach of licence conditions and misreporting.
8. MANAGEMENT OF THE FISHERY
8.1 Profitability of the fishery
All Falkland Island fishers generate licence revenue for the Falkland Islands Government. Within the developing private sector a number of joint ventures between fishing companies registered in the Falkland Islands and foreign partners, particularly of Spanish origin, have progressed the development of a local fishing industry.
The rajid fishery has in recent years been entirely prosecuted by Korean vessels. The quality of any business arrangements between these vessels and local fishing companies has tended to be low by comparison with the arrangements prevailing, for example, in the Loligo fishery. Nonetheless, the Rajid fishery has seen the development of some joint ventures and catch share agreements. Because the value of these arrangements is currently low, the profitability of this fishery to the Falkland Islands is dominated by the value of the licences sold and is supplemented by port and harbour dues.
It is estimated that the annual gross value of the catch to companies operating in this fishery is approximately £2M. Catch composition (the proportion of high value to low value species) and product presentation affect market value. Daily running costs of vessels and the costs of product transfer to home markets are also important. In common with other distant water fisheries, economics and profitability are further effected by the influence of international commodity and equity markets on vessel operation and company success.
Since their introduction in 1994 licences to target rajids have generated between £400 000 and £500 000 annually to the revenue of the Falkland Islands Government. This represents approximately 2.5% of the total revenue derived from fishing (£18.3M to £22M/yr) over this period (FIG 1995, 1998a, 1998b).
No rajids are landed, processed, or retailed, on the Falkland Islands.
9. MANAGEMENT COSTS
The Falkland Islands Fisheries Department has an active scientific research programme on the rajid fishery, which includes research done both in-house and contracted out. The majority of research activity to date has been directed to support estimates of standing stock biomass and contribute to the management of this fishery. The taxonomy and basic biology of the species supporting the fishery constitutes an area of current research interest. This programme has been designed to provide a more detailed understanding of the multi-species nature of this fishery that can subsequently be applied to the tuning of stock assessment models.
In the 1997/98 financial year the total estimated revenue from fisheries (principally from the sale of fishing licences) was about £18.3M, out of a total government revenue of £36.3M. For 1996/97 these figures were £22.3M and £40.8M (FIG 1998). By contrast the total expenditure on fisheries was £4.2M in 1996/97 and £5M in 1997/98. This expenditure includes research, as described above, surveillance (using fisheries protection vessels and aerial surveillance) and administration. The high allocation and priority given to research, about 25% of the fisheries budget (FIG 1994), reflects the priority given by the Falkland Islands Government to conservation and management of all exploited species.
Our understanding of rajid stocks around the Falkland Islands is the direct result of the collation and analysis of information collected by scientific sea-going observers and by scientific staff of the Falkland Islands Fisheries Department and Imperial College, London. Mr John Barton, Director of Fisheries for the Falkland Islands Government, provided comments on, and permission for, the release of this manuscript.
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