3. DISCUSSION

3.1 Freshwater aquaculture in Fiji - a brief review

Aquaculture in Fiji dates back to 1940 when the possibility of freshwater fish culture was first presented.

Following some initial attempts, the Government of Fiji introduced in 1962 the Inland Fisheries Programme that included fish culture.

In 1970, the United Nations Development Programme (UNDP) sponsored project (South Pacific Islands Fisheries Development Agency, SPIFDA) had the objective - among others - to assess the potential of aquaculture in Fiji. Although fish culture was a promising enterprise at that time, development was limited by the lack of expertise, experience, and suitable technology.

Since the 1970's development has increased. Several projects were implemented in the framework of various programmes with focus on different fields of freshwater aquaculture; e.g. introduction of new species into Fijian waters, improvement of infrastructure, introduction of new techniques, and development of rural aquaculture.

In the framework of the Eighth Development Plan (1981–1985) a programme was launched (Programme Four) to develop subsistence and commercial fish farming. Following development plans have included various components aiming at the development of different fisheries sub-sectors.

Since the late eighties human resource development has received increasing attention; fisheries officials have been given the opportunity to participate in various training programmes. They now have the task to implement extension programmes for farmers, although they still need training to get acquainted with latest developments.

Since 1982 the Japan International Cooperation Agency (JICA) provided grants for technical and financial support to develop aquaculture, notably to the development of NRS. This assistance lasted till 1994.

At present, in the field of freshwater aquaculture the FAO South SPADPI³ (GCP/RAS/116/JNP) has provides technical assistance to Fiji.

Rural aquaculture is still a major item in the country development plan and it was expanded in the Commodity Development Framework Programme of 1997.

³ SPADP Phase I: 1986 – 1992; Phase II: 1994 – 1999

3.1.1 History of species cultured at Naduruloulou Research Station

In relation to the functions of NRS a brief overview of production of freshwater species cultured at NRS is essential here.

Tilapia

Tilapia species were first introduced into Fiji in 1949, when the culture of Oreochromis mossambica was initiated at the Sigatoka Agricultural Station. In 1968 Nile tilapia (Oreochromis niloticus) was introduced which soon replaced O. mossambica, and became a well accepted fish in local markets.

In the framework of several projects on Tilapia culture, experiments were carried-out to identify appropriate strains; to develop feeds on the basis of locally available ingredients, to assess options for polyculture; and to introduce it to rural farmers. In 1982 a rural aquaculture training and demonstration project was established.

At present, Nile tilapia is cultured in one industrial scale farm (Viti Corps Co., Ltd., Navua); at seven commercial farms and at 210 subsistence farms. Fish seed is supplied to subsistence farmers from the state owned breeding stations (NRS and Dreketi Station), while the Viti Corps produces its own tilapia seed.

Carp species

Apart from the introduction of Common carp (Cyprinus carpio) in 1937 no significant event had been recorded until 1968.

In 1968, Grasscarp (Ctenopharyngodon idella), Bighead carp (Artistichthys nobilis) and Silver carp (Hypopthalmichthys molitrix) were imported from Kuala Lumpur for stocking into weed-infested inland waters and pond culture. Culture trials clearly proved that grass carp was suitable for control of aquatic vegetation. The carp species acclimatised themselves to local conditions, and according to feed trials, their growth rates were comparable to those of other countries.

Successful introduction and appropriate culture methods for Chinese carps were the pre-conditions of an extension programme. Experiments on induced breeding of Chinese carps were carried-out several times, and by 1972 successful hatching of eggs and satisfactory growth of fry could be achieved. In case of grass carp, however, the first successful breeding occurred in 1985 under the JICA project.

Grass carp fry were also imported in 1973 from India and in 1982 from China, and were mainly used for water weed control but farm culture was also considered for future utilisation. Rural villagers occasionally captured grown grass carp in rivers for consumption.

Experiments on pond fertilisation aimed to improve production under local conditions, and these attempts signal that the Government still considers the different carp species for local consumption in the long term.

In 1968 Common carp was also imported from Malaysia for pond culture and as the source of pituitary material. However, later on the stock was destroyed and the government banned this species.

Tawes (Puntius)

Tawes or Java carp (Puntius gonionotus) was introduced into Fiji from Malaysia in 1968 together with common carp for pond culture and to provide pituitary material.

Following successful attempts of induced breeding, a stock of P. gonionotus was built up to ensure an adequate supply of pituitary material. P.gonionotus is reproduced naturally especially in the Rewa River system and well appreciated by rural people.

Freshwater prawn

Freshwater prawn (Fijian name ura) is part of the fauna of Fiji and serve as the basis for prawn culture. Although the Macrobrachium lar is the indigenous species in Fiji, the Macrobrachium rosenbergii is the species first experimentally cultured. Seed production technique was developed successfully in mid-1980s under the JICA project, but its farming extension didn't occur before 1998.

3.1.2 Production

Production figures (Figure 1) well reflect the history of each species. Following the period of introduction and experiments a rapid increase of production may be observed in case of tilapia and prawn indicating that the sector is gradually moving from experimental stage to production phase.

[Note by SPADP's Chief Technical Adviser: The author referred production of freshwater prawn through FAO's statistics reports. However, freshwater prawn farming has never been boosted in Fiji till 1998. The Fiji Fisheries Division didn't know supplier of this wrong information.]

Production of Chinese carps, however, remained low (less than 1 tons), because they are only used for weed control in natural waters and in irrigation canals. After success of seed production, over 120,000 grass carp fingerlings were stocked into rivers till 1986. In 1994, 141,000 grass carp fingerlings were re-stocked into rivers. Under the CDF programme, Chinese carps are at present targeted for polyculture for diversifying production of freshwater fish.

Figure 1. Production of selected species

3.1.3 Future prospects

Freshwater aquaculture gains increasing importance in the South Pacific Region and in Fiji. Over-fishing of coastal areas has been reported from many islands, and the issue is on the agenda of several international institutions. Coastal aquatic resources are being depleted, and their replacement in terms of food source is managed through establishment and development of inland aquaculture, where appropriate natural resources exist. In this respect, Fiji is a country which has substantial freshwater resources and willing people to undertake freshwater aquaculture.

Fiji, based on past efforts, would have a good potential to rapidly develop freshwater fisheries if financial resource was made available. The Government of Fiji is strongly committed to take advantage of natural resource endowments; the aquaculture section of the recently launched programme on commodity development has been drawn-up in this spirit.

3.1.4 The Commodity Development Framework Programme

Although the focus of the present report is on the relocation of the Naduruloulou Research Station, the introduction of the Commodity Development Framework programme (CDF) is, however, essential here in order to place the production objectives of NRS into a national context. Implementation of the CDF programme will give the staff of NRS a key role in its realisation.

The Government of Fiji introduced the CDF programme in 1997 to improve the position of the economy. In this programme agriculture, and as its part the inland fisheries has an important role. Target figures were identified up to the year 2000, and development plans drawn-up accordingly.

The main objective for the aquaculture sector in CDF is

“… to promote aquaculture in the country and ensure that the country continues to enjoy good supply of fish and for possible foreign exchange earnings”⁴.

⁴ Fisheries Division: Annual Report 1994.

In order to achieve the objective CDF has identified four programmes for implementation:

• Establish culture of suitable freshwater species for food;

• Develop commercial and industrial farms capable of producing quality fish for local consumption and to cater for export market;

• Consolidate the subsistence in harmony with commercial fish farming by providing know how and market facilities to farmers;

• Provide through aquaculture stock enhancement of inland waters.

In terms of production volume three sub-sectors are distinguished:

• industrial fisheries: large scale and primarily export oriented, size of fishponds in a farm is 20 ha or more.

• small scale commercial fisheries, where production is for domestic sale with a pond surface of 1–2 ha, and

• subsistence fishery with occasional sale of surplus, whereas the pond surface is 1 ha or less.

Under the category of industrial freshwater fisheries there is currently only one firm-the government owned corporation Viticorp in Navua. The cultured freshwater species is tilapia with production process covering fish seed as well as market fish.

The CDF programme aims at the establishment of one additional enterprise of the same category.

There are 7 small scale commercial fish farms with this number projected to increase to 59 by the year 2000. It is also an objective of CDF that out of the 59 commercial fish farms about 13 should also produce tilapia fish seed for selling to other farmers. This means that an additional 9 small scale hatcheries are to be established within three years, and to be added to the existing 4.

Subsistence fish farming plays a significant role in fish production. At present there are 215 subsistence farmers and it is aimed to increase their number to about 500 by the year 2000.

In 1994 and 1995 about 50% of the production came from subsistence and small scale commercial sub-sectors.

The CDF objectives for aquaculture are summarised hereinafter⁵:

Research: Consolidation of Naduruloulou, Ba and Dreketi hatcheries and their development into research centres capable of handling freshwater aquaculture enquires. Mass production of good quality seed and supply to subsistence and commercial farmers at nominal cost. Conduction of selective breeding and genetic works on tilapia and its extension to other species.

Production objectives cover (i) increasing the involvement of women in aquaculture, (ii) encouragement of monoculture of tilapia in all sub-sectors, (iii) introduction of carp species to farmers and continuation of their use in water-weed control, (iv) increasing the number of farms in all sub-sectors, and (v) introduction of polyculture of tilapia, prawns and carps.

Human resource development objectives include both the improvement of scientific capability of staff through higher degree training and the training of farmers in subsistence and commercial farming.

Processing and marketing issues are also part of the CDF programme.

⁵ Fisheries Business Plan 1997 – 2000

The objectives of CDF are translated into data in Table 1.

Although the CDF programme is very ambitious, it should be regarded as a national plan and treated accordingly.

In relation to NRS the CDF programme may be interpreted as follows:

• Tilapia genetic (adaptive) research is to be continued, and suitable techniques of seed production to meet increased demand are to identified and mastered.

• Quality seed supply to subsistence farmers will primarily remain with NRS. Taking into account the supply of 8000⁶ fry per farmer, the annual production of 2 million fry means increasing the present production of NRS four times.

• The NRS will have the task of assisting the establishment of new subsistence schemes and of setting-up the planned new hatcheries. Provision of advice and conducting training programmes for subsistence and commercial farmers will also be a main task.

• NRS will, in addition, play a key role in feed development, including research and trial operations, which assumes improved human (management) and technical capacities.

• Production of grass carp juveniles for weed control in rivers and canals will be a government task, and thus the task of NRS.

⁶ Figure is reported by NRS officials.

Table 1. CDF aquaculture targets

An important element of CDF is to transfer seed production for commercial fish production to commercial hatcheries and to produce seed only for subsistence farmers.

3.2 Naduruloulou Research Station

NRS is located east from Suva, 7 km to the north from Nausori, along the Rewa River.

The earliest reference on Naduruloulou is in 1948 when an experimental pond was constructed. The next reference appears in 1973 when an expert proposal on the establishment of a self-contained carp hatchery was presented to the Government.

Construction of the NRS was initiated by the Government of Fiji in 1975, and by August 1976 the first set of ponds (12 ponds of 1.4 ha) were put into operation. In 1982 the Japan International Cooperation Agency (JICA) joined the project and provided assistance to further develop NRS. It has reached its present form through gradual extension with the financial support and technical assistance of JICA, in the form of research, consultancy, construction and provision of equipment. JICA support has continued since.

Although the primary function of NRS was specified as breeding and culturing grass carp, it was soon after its establishment envisaged as the future centre of inland aquaculture, but no detailed medium and long-term development plans were drawn up. Extension of facilities (construction works, laboratory development, etc.) were primarily based on immediate needs and available resources.

As NRS has extended, its weaknesses, and thus impediment to further development have became clear. Although many of the problems can be solved through gradual investment and improvement of management, the most critical problem faced at NRS is the regular inundation of the site by Rewa River.

3.2.1 Functions

NRS plays a key role in freshwater aquaculture of Fiji and specially in supporting the realisation of CDF programme. Its main functions are to:

• implement research on tilapia genetics, selective breeding and to maintain brood stock;

• implement research on various fresh water species as problems are identified;

• adapt and develop new breeding, nursery and rearing techniques to local conditions;

• develop human resources: ensure improvement in staff capability and organise training for private entrepreneurs;

• supply tilapia seed for subsistence farmers;

• produce (grass) carp juveniles for stocking into rivers and canals for vegetation control;

• produce freshwater prawn post larvae;

• enhance processing and marketing opportunities for export.

Activities related to the above functions have started long before the launch of CDF, but CDF is expected to give momentum to ongoing projects and to boost dissemination of results and operations on extension.

Production of freshwater prawn post-larvae will begin again in 1998, following a long period of inoperation.

The CDF programme makes reference to the production of ornamental fish, but this issue is still being under consideration.

Should relocation of NRS take place, the above listed functions will remain the basis of operation of the new establishment.

3.2.2 Seed production and applied breeding technologies

Appendix VI: “Basic data of technology applied at Naduruloulou Research Station” gives a summary on data used for planning seed production, but the figures must only be considered as preliminary ones. They, however, well reflect the applied technology.

Table 2 displays the facts and plans, the latter being from the CDF programme. In the light of past production the plans for the near future seem to be ambitious. Since seed production objectives determine the facility requirements of the new establishment following the relocation of NRS, a re-assessment of planned output figures is necessary.

With regard to the overall objectives of CDF programme the following comments may be made on the production schedule of NRS.

Table 2. Seed production facts and plans at NRS

Tilapia

Tilapia seed production is based on a simple method. Male and female spawners are put together in fibreglass tanks and left there for natural spawning. After three weeks, breeders and offspring are separated: larvae and fry are taken into rearing tanks, while the breeders are put into other tanks for recovery. Since no intermediate netting is made, age difference of fries may be as high as 5 to 15 days which is rather high for this species.

If demand for tilapia seed is higher then usual due to various reasons, some ponds are also used to produce fry. In such cases the procedure is very similar to that of the tank breeding. Duration of one cycle in ponds is about 4 to 6 weeks, but this period of time includes fry rearing as well. Following the harvest, breeders are separated into other ponds by sex. Although some ponds are dedicated to spawning, nursery ponds are also used for breeding.

Ponds used for tilapia breeding are dried following each production cycle, usually every 6 or 7 weeks.

Sex reversion techniques have not yet been applied. There are some concerns about the use of hormones treatment to obtain monosex population. Fisheries authorities of Fiji have requested the Food and Drug Administration of the US to issue expert opinion on the possible effect of application of synthetic androgen, methyl testosterone on humans.

Tilapia seed is provided to subsistence farmers free of charge.

It is assumed that demand for seed supply to farmers would be well balanced throughout the year. Based on the methods and figures of production planning currently in use (Appendix VI) the theoretical annual capacity of the 10 hatching tanks is 240,000 tilapia fry, while that of the 13 nursery⁷ ponds is 600,000. Compared to literature data, there is a considerable reserve in production capacity provided that management and techniques improve.

The presently applied tilapia seed production technology gives little or no room for human intervention if problems occur, and, therefore, opportunity to exercise control on the process is the minimal.

Planned increased in tilapia seed out-put is very high, though it is not impossible to reach provided that some measures are taken. Basically, increase may be achieved by Option A: inclusion of more or all ponds in the production cycle or Option B: introduction of new techniques. Success of either options depends on improved management.

Option A is a simple extension of current methods: the greater the number of ponds the greater the output. Taking other functions of NRS into consideration, integration of additional ponds into production is limited. Although the total pond surface is sufficient, the size distribution is not suitable for balanced seed production.

Continuous and balanced output assumes that pond areas in each production cycle are similar. This condition cannot be secured at present.

Option B, introduction of new techniques gives more opportunity to improve tilapia seed production. Number of spawners either in the tanks or ponds may be increased, but the manageable stocking numbers must first be identified through trial operations. The same applies to pond breeding. A next step is to introduce more control on production processes: notably the regular collection of larvae and their separation in tanks which results in a number of different age groups but with uniform size of fry in each age group.

Further to increase the annual output, controlled hatching techniques, e.g. collection of eggs and hatching in jars should be introduced.

As a conclusion, the current methods of breeding technology and available facilities have considerable limitations in efficiency and productivity. Improvement of current techniques and introduction of new methods would allow reasonable expectation of achieving the targeted output.

In terms of time, however, three years to achieve the set objectives is rather short; teaching and training of staff, gaining experience and mastering techniques need time.

Furthermore, if relocation of NRS takes place, a substantial delay would be expected during the transfer period.

Chinese carps and Puntius

Besides the production of Tilapia seed for further culture at subsistence and small-scale commercial farms, the production of grass carp for weed control of natural water and irrigation canals and production of other Chinese carp species also take place at NRS.

Chinese carps and Puntius seed production is also based on simple method. Hormone treatment is applied to induce spawning, but actual spawning and hatching take place in a natural way in large tanks. Hatchlings of age one week are reared in ponds to a size of about 100 to 200 grams, then they are stocked into rivers and canals. If there is demand, fingerlings are given to farmers for further grow-out.

Neither the past nor the future production figures create problems for a hatchery like NRS. Capacity of NRS is far above the demanded output.

Although the present demand for supply of carp fingerlings is low, and plans include no substantial increase, the CDF programme makes several references that imply increased future demand. Introduction of carp species to farmers, introduction of polyculture of tilapia prawns and carps will probable induce a good demand for carp fingerlings.

Freshwater prawn

Freshwater prawn (M. rosenbergii) has not been produced at NRS since 1991 and the production target as presented in Table 2, therefore, must be treated with due care.

It is assumed that production of prawn post-larvae would practically start from zero, and the targeted output can only be reached with some years of continuous efforts.

⁷ Nursery ponds are used for tilapia breeding.

3.2.3 Facilities

Reference is made to Appendix V: “Facility at Naduruloulou Research Station”. Development of facilities took place over a significant period of time, and was based rather on available financial resources than on medium and long term development plans. The present set-up has been developed step-by-step and traces of gradual extension can be observed all over the compound.

Water to the site is supplied from Rewa River by continuous pumping. Since sediment facilities are weak, a supply of clean water can only be maintained with great efforts. Furthermore, Cyclone Kina has seriously damaged the pump intake.

The site is open to a side valley which is part of the inundation basin of Rewa River. The NRS occupies about 10 ha and accommodates 40 ponds with a total pond surface of 4.56 ha. Elevation of site varies between 3.50 to 11.0 m above mean sea level (amsl). The elevation of pond crests are a maximum of 6.0 m amsl. Buildings occupy the upper part of the site.

The size of ponds varies between 0.03 and 0.45 ha. Although each pond has a defined function, (e.g. spawning, nursery or rearing) actual utilisation depends on their availability and immediate needs. Although the total pond surface is large enough, the number and size distribution are not favourable to maintain increased and balanced seed production.

Breeding facilities for the cultured species are separated from each other. For the purpose of tilapia breeding, 19 pieces of fibreglass circular tanks are set-up together with additional 2 concrete tanks. Their total volume is 400 m³. The tanks are about twelve years old and their plastic lining is worn out. Replacement is difficult because the lining material is no longer manufactured and no substituting material has been offered by the manufacturer of tanks. Carp breeding takes place in the hatchery and in an outdoor circular concrete tank. The facilities for prawn post-larvae production are mainly circular plastic tanks of 500 litres with some additional tanks of 1,000 litres accommodated in another hatchery building. Drainage of ponds is through a drainage canal which connects into Rewa River.

Buildings include an office, a carp hatchery and laboratory block, a separate building for prawn breeding, a feed processing unit for on site feed production and a workshop for machine maintenance. In general, the buildings are in fairly good condition.

The laboratory is relatively well equipped, but some of the equipment is worm out and the overall laboratory needs up-grading.

The site is fenced approximately 1,600 m in length along the low elevated area; its height is 4 m in order to prevent fish escape during inundation of site and for protection against unauthorised entry.

Infrastructure, e.g. electricity and communication facilities are available on the site.

3.3 Justification of relocation - constrains of operation

After two decades of operation the NRS faces several problems of which some are serious and need solutions.

3.3.1 Site flooding

The most serious problem is the frequent inundation of site caused by tropical hurricanes usually accompanied with heavy rains. The site is located in the close vicinity of River Rewa at a distance of approx. 300 m. Since the ground level of the site is mainly between 3.50 and 11.00 m amsl, substantial increase of water level in Rewa River causes flooding of the site. Due to the importance of the issue, Appendix: “Assessment of inundation of the Naduruloulou Research Station” is specially being dedicated to the problem.

In view of frequent site inundation JICA has reduced its support to NRS until a reliable solution for flood protection is provided.

Taking the assessment result into consideration, it may be concluded, that the site of NRS is frequently flooded, and the frequency is about once in every five years. This frequency is not acceptable for an aquaculture research centre.

There are two options to handle the issue: option A is to invest into engineering solutions for flood protection, while option B is to relocate the research station to a safer location.

Option A means the construction of a flood dam with all necessary structure including flood-gates to maintain drainage, while preventing inflow of water to the site. In this case the proper height of dam must be calculated on the basis of precise hydrological investigations, but required hydrological data are probably missing. It is likely to conclude the dam height at the level of around 6.50 m amsl. Flood dams must satisfy rigorous standards that will make construction very costly. Estimated volume of earthwork is about 100,000 m³, (assumed dimensions: 5 m crest width to allow free movement of maintenance machines, 1:3 slope on both sides the minimum, 3.5 m of height, 1,700 m of length), which is about 150% of the volume of earthwork of the proposed new establishment at Navua.

3.3.2 Other constrains

Rain water on site

Rainwater on the site creates fewer problems, only immediately after rain. The site is surrounded with hills on three sides, and all surface runoff takes place through the NRS site. The problem is manageable by constructing trenches at the hill foot adjoining to the site.

Water supply and de-silting

Water is supplied from Rewa River by continuous pumping. During Hurricane Kina the pump stand was damaged but fortunately it does not hinder seriously the operation of pump. Lining and bank protection have also been damaged.

Silt and suspended solid content rapidly increase in the river water following medium and heavy rains, and NRS has no facility for settling. By the end of rainy seasons about 30 m³ silt accumulates at the bottom of the reinforced concrete reservoir of 237 m³. The amount of silt is about the 13 % of the reservoir storage capacity. In case of present production volume the problem is manageable, but any substantial increase of production would require reliable long-term solution for de-silting.

In other areas of water quality no considerable obstacles have appeared so far.

Tanks and ponds

The fibreglass tanks are 12 years old and their plastic lining needs replacement. Since the lining material is out of manufacture and no reliable solution for replacement could be identified, construction of new tanks will likely soon be necessary.

Increasing of seed production calls for the improvement of pond arrangement. Pond size and number should correspond to the schedule of seed output.

Estimated volume of earthwork is about 7,000 to 10,000 m³ or in other terms the 10 to 15 % of the total pond volume.

Energy supply

Electricity supply facilities need improvement; voltage fluctuation is a regular problem. Operation of different machines and equipment must be synchronised to avoid failure of energy supply. A three-phase transformer is needed to ensure stable energy supply, and the internal electrical lines need to be replaced.

3.3.3 Conclusion

The main constrain of NRS is the frequent inundation; the probability of occurrence is about 20% and that is not acceptable. Appropriate counter-measures must therefore be taken.

If the research station remains at Naduruloulou, the construction of a flood dam and floodgate is inevitable. Furthermore, pond re-arrangement is also necessary in order to maintain appropriate schedules of pond operation. Repair of the pump stand is a priority. Long-term solutions for setting river water before distribution on site is a pre-requisite to manage research on a higher level and to improve production. Protection against voltage fluctuation needs improvement of electric network and installation of a three-phase transformer.

In addition, the construction of a flood dam would block any kind of future expansion.

It can be stated that neither the construction of a flood dam, nor the re-arrangement of ponds would solve the problems. The option to relocate NRS, therefore, is the only solution to the current problems.

3.4 Future utilisation of the NRS site

Should a decision be made in favour of relocation of the Naduruloulou Research Station, the issue of further utilisation of the Naduruloulou site must be solved. In this respect the following points must be addressed.

The present site can only be considered for long-term use with serious limitations, primarily due to the risk of frequent flooding. These limits will remain, thus if the research centre operates at Naduruloulou problems will still occur.

Furthermore, there is no need to operate two research centres with the same functions in Fiji. Assuming that two research stations operate at the same time, the staff, equipment and financial resources must be doubled with all related consequences.

Since all present functions of NRS may and must be transferred to the new research centre, no exclusive function remain at Naduruloulou, so there is no need to operate it as a research station.

As a conclusion, following the relocation of NRS there is no need to continue to operate the present research centre.

Pond facilities might be used for fish production. Since production cycle of tilapia is shorter then one year, it might be feasible to run a commercial venture. Problems of operation must, however, be made clear to potential entrepreneurs.

3.5 Site selection for relocation

3.5.1 Summary of sites

Fisheries officials selected three sites for advance assessment by the consultant. These sites are located at:

• Lakena (Viti Levu),

• Navua (Viti Levu), and

• Belego (Vanua Levu)

Findings at each site are detailed in Appendix VII: “Site assessment”, but a brief summary is given hereinafter.

Due to the short period of time made available for site visits it is not possible to assess them on the basis of detailed engineering vs. cost analysis. The sites, therefore, are compared to each other on the basis of their physical properties and potentials.

Location, size and layout

Locations of each site are presented on Figure 2. Each site is of flat area; ground level varies within 1 to 1.5 one meter only. The available sites are larger at Lakena and Navua than the size of NRS. At Belego the site area is 6.4 ha, which is slightly more than the total pond surface but less than the site area of NRS. It is reported that some additional land owners at Belego might be willing to sell their land, although this willingness is not yet verified.

Figure 2. Location of sites assessed by the consultant

Soil

The soil conditions are very similar at each site. The soil is of clay. It is good for dike construction.

Water supply

Water supplies to site for pond filling and hatchery use are different, although each site can probably be provided with required amount of water with the following limitations.

1. At Lakena water is available from the Rewa River, which means the installation and continuous operation of a pump station at the river bank. In addition, suspended sediment content is visibly high, and the water needs settling before releasing to ponds. Moreover, for use in the hatchery additional filtration might be necessary. Drainage may be done by gravity.

2. The Navua site has all the desirable potentials: gravity supply and drainage from an existing reservoir through existing irrigation and drainage canals.

3. At Belego water may be secured from a nearby creek. Although the amount of available water is reported by locals to be high all the year round, verification of availability needs further investigations.

Infrastructure

1. Each site is accessible by road but quality varies.

2. Electric energy supply can be secured at each site from nearby electric transmission lines.

3. Supply of drinking water is available within a close distance only at Lakena and Navua.

4. Communication facilities (e.g. telephone lines) are available in the close vicinity of the sites at Lakena and Navua.

5. Community infrastructure, such as (primary) school, medical centre and shops are available in a reasonable distance only at Lakena and Navua.

3.5.2 Recommendation for site selection

Taking all the physical properties and potentials of the visited sites into consideration, the proposed site for relocation of NRS is the site at Navua.

The Navua site (i) has the advantages of gravity water supply and drainage potentials, (ii) it is large enough for future extension if required, and (iii) all infrastructure facilities are available at short distance. In addition, (iv) there it a high potential of aquaculture estate development in the surrounding areas.

It is also necessary to mention here (v) the potential for cooperation with Viticorp. This cooperation may cover various topics, such as research, training and large-scale trial operations based on achievements of the research centre.

Following the selection of the site, further consultation with Viticorp⁸ executive was held in order to locate the exact plot within the general area. Location of site is presented on Figure 2 and on drawing No. A-1.

⁸ At present, Viticorp is the owner of the land.

3.6 Presentation of the new aquaculture research centre at Navua

Reference is made to

• Appendix VIII: “Technical report on the new aquaculture research centre at Navua”, and

• Appendix IX: “Cost Estimates”

3.6.1 Location, accessibility and existing infrastructure

The site is located at the north of Navua town, about 1,5 km from the Suva - Navua main road on the right side, and on the left bank of Navua river at the foot of hills closing the valley from the North, between the main irrigation canal and the existing Viticorp fish farm.

The site area is 17.7 ha excluding the residential and so called recreational areas.

On the north the irrigation canal, on the west a natural depression (arm of the creek) and on the south a road close the site. There is no natural or human made formation to use, as boundary of the eastern side, but this may be the direction of future expansion.

Ground level varies between 3.50 – 4.00 m amsl, but along the Wainakavika Creek it is only about 2.00 m amsl. The site is accessible from a road on the left bank of the main irrigation canal from the Navua - Waiyanitu road. The distance from road to site is about 700 meters.

Electricity power supply is available at the Viticorp hatchery, about 1,100 m in distance.

Drinking water and telephone line are along the Navua - Waiyanitu road.

3.6.2 Functions and production objectives

The new aquaculture research centre at Navua will take over all functions of NRS. Accordingly, as it is detailed in chapter 3.2.1 it will operate as a national

• research centre:

  • to conduct research on tilapia genetics, selective breeding and to maintain brood stock;

  • to conduct research on various fresh water species as problems are identified;

• tilapia, carp and freshwater prawn seed supply centre;

  • to adapt and develop new breeding, nursery and rearing techniques to local conditions;

  • to supply tilapia seed for subsistence farmers;

  • to produce Chinese carps juveniles for stocking into rivers and canals;

  • to produce freshwater prawn post larvae;

• human resource development (training) centre;

  • to ensure improvement in staff capability;

  • to organise training for subsistence farmers and private entrepreneurs; and

• development centre for processing and marketing.

Functions originally associated to NRS are hereinafter treated as functions of the new aquaculture research centre.

Accordingly, the new research centre provides good options for various operations of research, seed production and training in parallel. Although the total pond surface at Navua is only 25% more than that of NRS, the pond pattern will enable the staff to maintain well balanced seed output throughout the year.

Research will include the assessment of new strains or species that may be imported from abroad. Fish will also be brought to the centre from wild waters or from farmers. It is, therefore, important to provide facilities for fish health control before they enter the site. For this purpose, construction of quarantine tanks is planned at a segregated section of the site.

Although the CDF programme identifies tilapia seed production for subsistence farmers only, it is recommended to consider the new centre as a quality fish seed supply source for commercial farms as well in future. This issue is discussed in details in chapter 0:"

Recommendations":

Capacity of the centre is specified on the basis of the objectives of CDF, but with continuous improvement of management, and mastering techniques of production, seed output may be even more.

Accordingly the initial production output is set to:

Number of ponds and other facilities are computed on the basis of figures presented in Appendix VI: “Basic data of technology applied at Naduruloulou Research Station”.

The production potential of the new research centre is higher than that required for the present, but this allows for future needs, and provides for increased operational capacity.

In case of tilapia the proposed technology is based on the current method, but extended to the collection of just-feeding larvae for further growing. As a next step, the collection of eggs and hatching in jars is proposed in order to achieve full control of the process.

Introduction of new carp breeding technology would be necessary if demand increases substantially. In such case the hormone induced ovulation (current method) should continue in artificial egg fertilisation and hatching and rearing in vertical flow-through type incubator / rearing jars.

Production figures of prawn post-larvae (PL) imply that there is no well established technology in use at present in Fiji.

The introduction of clear-water production system is proposed and facilities are planned accordingly. Salinity of water for fry rearing will be maintained by mixing sea water brought to site and freshwater originating from the reservoir.

In general, the presently available tanks of the prawn and carp hatcheries of NRS will be moved to the new centre but some additional concrete tanks will be constructed.

The number and variety of jars, troughs and tanks fibreglass, plastic and concrete both indoor and outdoor will provide good options to conduct various research programmes.

While in respect to tilapia and carp seed production, research would focus on the extension of currently applied propagation methods, notably on the adaptation of advanced technologies to local conditions, adaptive research to establish sound techniques for mass production of prawn is required.

3.6.3 Pond pattern

Pond pattern is developed on the basis of a 1:5,000 scale map made by the Land and Water Resources Management of MAAF and detailed drawing of the irrigation system in the 80s.

Number of ponds proposed is 78 with a total water surface of 5.81 hectares. Details on pond dimensions are presented in Table 11: “. Schedule of ponds” in Appendix VIII, but an extract is given below in Table 3.

Table 3. List of ponds at Navua (extract)

Although some ponds are exclusively assigned for research and training of farmers, all ponds may be linked to seed production if so required. Dimensions of research and demonstration ponds fit well into the overall system.

The ponds are earthen with natural soil base. Their size is defined according to the operating requirements. Each pond is assigned to a specific function, but on the basis of detailed management plans ponds may be used for other purposes.

Ponds assigned to carp production have a water depth of 1.5 m, while for all other ponds the water depth is 1.00 m. Each pond outlet is accessible by small trucks on the dikes.

Dike cross-sections follow uniform dimensions; side slopes are 1:1.5 on each side, crest width is 3.00 m on the shorter side of ponds in general, but where drainage structure exists the crest width is 4.00 m to allow the traffic of small trucks. Crest width of separation dikes is 2.00 m.

Crest level is uniformly 4.00 m amsl. Following detailed site levelling prior to the preparation of final designs, adjustment should be done of crest levels, and accordingly, of the water and bottom levels to reduce the quantity of earthwork. Free board over operational water level is 0.5 m everywhere.

3.6.4 Water supply and drainage

As a general rule, water supply to the site and drainage are managed by gravity, which considerably reduces the operational costs of the research centre.

Water supply

The research centre has the water supply secured from the nearby reservoir constructed for irrigation purpose in the late eighties. The reservoir has the capacity of 3 million cubic meters with an operational water level of 12.00 m amsl.

Water for pond filling and for the outdoor concrete tanks is taken from the irrigation canal by branching out at Section 1,400. The irrigation canal bottom elevation is between 4.80 and 5.00 at the intake to the research station, which provides good options for gravity supply.

The water is filtered through stone chips of various sizes, and collected in a tank for further distribution to the site. Distribution of water to ponds and tanks is by four pipelines of 200 mm diameter each. The four lines will serve four groups of ponds separately. This set-up has the capacity to fill all ponds within 12 to 15 days of continuous operation.

Outlets to ponds are pipes of diam. 100 mm branching from the mains.

The hatchery and ponds are supplied with water separately. A 200 mm diameter PVC (pressure) pipe leads from the irrigation canal intake at the reservoir to a ferrocement elevated tank on the right bank of the canal. This tank always has a water level the same as that of the reservoir, and provides sufficient supply to the hatchery.

Quarantine tanks need no extra volume of water, since they operate occasionally and the amount of water may easily fit into the overall demand of the compound.

The annual water demand for the

In terms of one-time maximum discharge, the demand for the

Permission for using the reservoir water and irrigation canal must be arranged with the authority involved on the basis of the above detailed water demand.

Drainage

Drainage of water from the compound is to the Wainakavika Creek, except for that of the quarantine tanks. Drained water of the quarantine tanks is collected in a separate septic tank, and discharged to the creek only following proper treatment as per health and environmental standards to prevent environmental contamination.

Drainage of ponds is through monk type sluices into drainage canals. This ensures the control of water level and automatic release of excess water.

The maintenance of the drainage canal is easier and it can be more easily kept clean than drainage pipes, although the latter occupy less site area.

3.6.5 The hatchery-laboratory block

The hatchery-laboratory block comprises the laboratory hall and two separate semi-open sheds for tilapia and carps, and for freshwater prawn respectively.

The Tilapia-Carp hatchery is equipped for brood fish handling and treatment, and for hatching of eggs and rearing of larvae.

The Prawn hatchery is equipped for the application of clear-water post-larvae production system.

Contrary to the freshwater supply system, whereas replacement of water is from the reservoir and no recirculation is made, brine will be circulated through simple bio-filters in order to remove ammonia and nitrite. Each concrete tank is served with individual bio-filters.

The Prawn hatchery has also devices for hatching Artemia to provide feed for post-larvae.

All hatching and rearing tanks are connected to a common air supply system. In case of electric power failure a diesel engine will power the air-blower.

The laboratory is similar to that of NRS: all equipment and instruments of NRS should be transferred, but replacement of worn out ones may be necessary.

The laboratory will serve both hatcheries, and, therefore, access is ensured. Within the laboratory building separate rooms are for storing hatching tools, feed, chemicals, etc.

A completely separated section of the building, about 10 m², accommodates the air-blower and emergency diesel engine. This room is accessible from the yard.

The area of the block is:

The large out-door concrete tanks are primarily for tilapia breeding, but may be used for other purposes, if required. The circular concrete tank is for induced breeding of Chinese carps.

3.6.6 Administrative and ancillary buildings

The administrative centre of the compound is the office building. It accommodates the offices for management, the staff room, and lecture room. Its floor area is 200 m².

For the effective operation of the research centre some additional buildings should be constructed.

The feed-processing unit of NRS shall be transferred to the new research centre. It shall be extended with a feed store. Fishing gears and other equipment shall be kept in a separate store of 120 m².

A workshop (70 m²) and open shed (100 m²) shall serve the purpose of machinery maintenance.

A dormitory of 200 m² shall accommodate about 20 participants for various training programmes.

3.6.7 Infrastructure

The research centre shall have all the necessary infrastructure for proper operation, e.g. electricity supply, drinking water and sewage system and communication facilities. According to Fijian standards, the recreational ground is reserved for staff use.

3.6.8 Residential buildings

Civil servants in Fiji are provided with housing by the Government. The research centre, therefore, shall include the residential compound to accommodate about 25 – 30 staff members and their families. There are two sites initially identified as suitable for such purpose.

3.6.9 Cost analysis

Details of cost estimates are presented in Appendix IX, and are summarised hereinafter in Table 4.

During the consultant's mission the Fiji dollar devaluated by 20%. It is, therefore, necessary to note here, that the cost estimates have been prepared following such devaluation and reflect prices of February 1998.

Provision of housing facilities for staff is not a usual component of project cost. Accordingly the projection of cost over certain units of the project is made in two ways: (i) including and (ii) excluding residential facilities.

Cost estimates do not include the acquisition of land. This issue must be settled and agreed between the Government and the current land owner, Viticorp.

Table 4. Summary of cost estimates

Investment cost projected to pond area and production output is as follows.