Commercial aquaculture in Nigeria: a vertically integrated approach in the commercial freshwater farming of tilapia in floating bamboo net-hapas and cages systems

Tilapia once termed "poor man's" fish, still remains as the highly-priced food fish in many developing countries. The good attributes of this fish prompt its use in intensive aquaculture vertically integrated systems (VIS) which embrace broodstock development, hatchery/nursery and growout phase. Based on the series of studies carried out at Kainji Lake Research Institute, in New Bussa, Nigeria using Oreochromis (Tilapia niloticus) in floating bamboo hapas/cages, the recommended intensive modular systems were estimated to be capable of producing 4 million Tilapia fingerlings and 729 tons fish (Market-size) annually. Cost-benefit analysis showed the venture to have high prospects. It is recommended that priority be given to Tilapia cage culture at the national level in order to contribute immensely towards increased fish production

The role of communication in the management of Nigeria's capture fisheries resources

Development and management indices identified in the capture fishery resources focus on stock management, freshwater and marine pollution by organic and inorganic compounds including silting, plankton sustainability, fishing methods, biological productivity, energy cycles, ornamental fish and sanctuaries. The issue of post-harvest handling and processing is also discussed. The paper also identifies fisheries sectorial problems at the artisanal and industrial level both at sea and at shore, in the processing plant, infrastructure, manpower and marketing issues. The paper suggests that advocacy should be incorporated into extension and communication programme ensuring some changes in attitudes of all stakeholders in the fisheries game. The paper concludes stating that policy makers should stop paying lip-service to the fisheries sub-sector and should create a separate Ministry for Fisheries

Plankton periodicity and some physicochemical parameters of the intake channel of Lake Chad

This study examines zooplankton periodicity and some physicochemical parameters of the intake channel of Lake Chad (Nigeria). Nine different zooplankton species were identified at the sampling station 1, while seven different zooplankton species were identified at the sampling station 2 (the intake channel of Lake Chad). Each identified zooplankton species was grouped according to its major group of copepods, Cladocera or Rotifera. The copepods dominated the zooplankton community with the highest numbers of occurrence as Cyclopedia species throughout the course of the study at both station l and 2. There was a clear evidence of the influence of organic manure nutrients on total zooplankton population at station 1 when compared to that of station 2. The water quality variables measured in the course of this study show that the surface water temperature in station 1 ranges from 27.5 degree C to 30.5 degree C. The pH ranges from 6.8 to 8.5, while D.O. contents ranges from 2.9mg/L to 6.1mg/L and alkalinity recorded was 172.00 to 208.00. At the station 2 the water quality parameters obtained show that surface water temperature ranges from 27.3 degree C to 30.2 degree C, pH ranges between 6.9 to 8.5, while the D.O contents ranges from 3.0 mg/L to 6.2 mg/L.Alkalinity ranges from 172mg/L to 212 mg/L

Effects of different types of fertilizers on plankton productivity in earthen ponds

Three fertilizer types (NPK, Super-phosphate and cow dung) were applied at two levels (Low, 0.3 kg/25m super(2)/2weeks and High, 0.7kg/25 m super(2)/2weeks) to 12 ponds with two ponds serving as control. Each pond had an area of 25 m super(2). Application of fertilizers and monitoring of plankton productivity and water quality parameters continued fortnightly for 52 days. Results obtained were subjected to Statistical Variance Analysis. The abundance of phytoplankton was in the order: Chlorophyceae > Bacillariophyceae > Cyanophyceae > Desmideaceae. While that of zooplankton followed the order: Crustacean > Rotifer > Protozoan. Primary productivity showed a variation between treatments with lowest value of 5592 mg/O sub(2)/m super(3)/day obtained in the control and cow dung low application rates (1.5 kg/25 m super(2)/2weeks). The highest value for primary productivity was obtained at M sub(2) (0.7 kg/25 m super(2)/2weeks, N.P.K) with primary productivity value of 7200 mg/O sub(2)/m super(3)/day, closely followed by M sub(4) (0.7 kg/25 m super(2)/2weeks, super phosphate) with 6792 mg/O sub(2)/m super(3)/day.

Prevalence of endoparasite in some commercially important freshwater fishes of Bida area, Niger State: a preliminary report

The result of this preliminary report highlighted prevalence of an endoparasite (nematode) in order of prevalence. Four non-scaly commercially important fishes, namely:- Clarias sp Hererobranchus bidorsalis. Bagrus sp and Synodontis sp.; and nine scaly fishes, namely; - Gymnarchus sp, Protopterus annectus. Tilapia sp, Lates niloticus. Heterotis niloticus, Mormyrops sp, Channa Obscurus, Labeo sp and Distochodus rostratus of freshwater fadama of the Bida Area, Niger State. The extent of the spread was evaluated. While the reactions of fishermen, middlemen (fishmongers) and fish-eaters in order to appreciate the impacts of the nematode infested fishes on the populace were recorded. The paper suggested areas for further studies towards evoking desirable management strategies for the study area as follows. Such suggested areas are:- Identification and confirmation of the nematode species; life cycle of the nematode species; influence of season on the prevalence, spread and pathology in the nematode infested fishes, etc

Salvaging the freshwater ecosystems in Nigeria: great threat to sustainable fisheries and aquaculture development

Nigeria, the country of many rivers is also rich in lakes, and wetlands, sustainable and wise use of these inland aquatic ecosystem and water resources has become a matter of widespread and intense concern. Unhealthy freshwater ecosystems and seriously diminishing and unequal availability of quality freshwater call for high quality limnological research and expertise to underpin the enhancement of sustainable fisheries and aquaculture development.In every regard of national health, agriculture and economics, the continued over exploitation and misuse of finite freshwater resources is directly causal to the progressively deteriorating fish production and general standard of living.The integration of basic understanding of inland ecosystems with applied problems and their solutions should be of fundamental concern to all stakeholders in our freshwater resource. This is a basic element in creating an attractive and security ensured economic for investment in fisheries development, including aquaculture. This is the focus of this paper

Assessment of inland waters fisheries in Nigeria with implications for improved freshwater fish production, poverty alleviation and food security

Rapid Appraisals of the current fisheries situations of some selected inland water bodies in Nigeria were carried out within the framework of Aquaculture and Inland Fisheries Project (AIFP) Annex II of the National Special Programme for Food Security (NSPFS). This paper presents the results of the fishery assessment of one of the selected inland water bodies (Sabke Lake) in Nigeria with a view to optimizing the fish yield through the adoption of improved culture based fishery techniques and community-based fisheries management. The lake is unmanaged and the fishing pressure was found to be very high. Also a number of fishermen were found using small mesh size nets to crop the juveniles of highly valued fish species for an optimum catch. About 14 fishermen ought to have been engaged in full time fishing activities if the fisheries of this lake is to be managed on a sustainable basis. However, a surplus of over 100 fishermen was recorded actively fishing during the period of the study. The results further revealed that Fisheries Rules and Regulations were not established for the national exploitation and proper management of the fisheries of many inland water bodies including Sabke Lake. All these have a depilatory effect on the abundance and sizes of fish harvested from the nigerian inland water bodies especially Sabke Lake. A community based management system that establishes a participatory involvement of fishermen in the conservation and national exploitation of fisheries resources for their own well being is recommended for Sabke Lake and other inland water bodies in Nigeria

The relationship between some physicochemical parameters and plankton composition on fish production in ponds

The effect of physico-chemical parameters and plankton composition on fish production in ponds was investigated in six fish farms for eight weeks. The physicochemical parameters investigated were temperature=25-30 plus or minus C, transparency=0.45-0.57m, dissolved oxygen=3.0-10.9mg/l, pH=6.0-7.7, dissolved carbon dioxide=5.46-28.3mg/l, total alkalinity=44.37-80.0ppm, chemical oxygen demand=31.88-72.18mg/l and biological oxygen demand=0.66-48.34mg/l. Plankton composition varies and was made of four families of phytoplankton namely; Cyanophyceae, Chlorophyceae, Dinophyceae and Diatomida; and four families of zooplankton viz; Protozoa, Rotifera, Copepoda and Dinoflagellates. Farm 1 and 6 recorded the highest average weight of about 1.0kg and average total length of about 40.0cm for the two fish species. This study showed that fish yield was dependable on the quality and management of pond water characteristics

Growth response of Heterobranchus longifilis fingerlings fed with varying levels of dietary freshwater mussel (Aspatharia sinuata)

A common bivalve: Freshwater mussel, Aspatharia sinuate was evaluated as a dietary protein supplement in the production diet for Heterobranchus longifilis fingerlings with mean body weight 8.34 plus or minus 10g reared in aquaria tanks. Four diets containing fishmeal protein at a rate of 25%, 50% and 75% along with the freshwater mussel flesh were formulated. The diet without the freshwater mussel served as the control. The fish fingerlings were fed at 5% body weight per day for 56 days. It was revealed at the end of the experiment that freshwater mussel was most suitable as a protein supplement when incorporated at 25% replacement. The body weight gain, specific growth rate and feed conversion ration values of 6.83g, 1.06% day and 0.62 respectively were highest in diet with 25% replacement closely followed by diet with 50% replacement. Beyond 75% inclusion level there was no significant growth (P>0.05). However, complete replacement of fishmeal by freshwater mussel decreases growth rates and should not be used in Heterobranchus longifilis diets

An analysis of Nigerian freshwater fishes: those under threat and conservation options

The study assessed qualitatively the threat status of all nigerian freshwater fishes using such criteria as rarity, size at maturity, mode of reproduction, human population density, habitat degradation, pollution and range of each species among others. The biology of 48% (129n) of nigerian freshwater species is not well known. Of the 266 known freshwater fishes, 47 species represented 17% are critically endangered, 15 (5%) are endangered , 8(3%), are vulnerable while 23(8%) are near threatened. The paper suggests increased basic knowledge of threatened species and conservation policy along three lines public awareness, legislation and creation of national parks, aquaria and reserves as measures needed to ensure the conservation of the fishes

The impact of varying nutrient regimes in earthen freshwater ponds on the comparative ecology of diurnally occurring candidate live feeds

The daytime composition and relative abundance of zooplankton species were studied in three treatments of two replicate earthen ponds each with nutrient sources and water replenishment regimes. Treatment -A (200m super(2) surface area supplied 900kgha super(-1) pig manure only). Treatment -B (200m super(2) surface area supplied 70kgha super(-1) month super(-1) pig manure, 50kgha super(-1) month super(-1) N.P.K. [15:15:15] and 30kgha super(-1) month super(-1) Urea) and Treatment-C (1500m2 surface area supplied 1150kgha super(-1) month super(-1) commercial grade 40% crude protein compounded feed). Water replenishment for Treatment A was daily tidal deluge from the New Calabar River while that for treatment B and C was from column-well and occasional rains. No zooplankton species were recovered from the pig-manure only treatment (A) while only Diffugia constricta and Difflugia urceolata were the two protozoans that occurred together in treatments B (combined fertilization) and C (compounded feed only) in contrast, Difflugia acuminate and three rotifers, Collurella uncinata, Diurella stylata and Keratella quadrata occurred only treatment B. similarly, Arcella arenaria, Arcella costata, Centropyxis aculeate, Difflugia pyriformis, Branchionus calyciflorus, Lepadella patella, Polyarthra trigla and Onchocanmptus mohammedi were recovered from treatment C. Arcella costata was the most abundant zooplankton in the entire experiment, while Arcella arenaria was very abundant in treatment C, Collurella uncinata was very abundant in treatment B. The inference is that combined fertilization of earthen freshwater ponds tend to be more suitable for the culture of rotifers such as Brachionus calyciflorus, popular in fish larva nursery, while those supplied compounded feed could be used to produce protozoans where desirable

The relationship between some physicochemical parameters and plankton composition on fish production in ponds

The effect of physico-chemical parameters and plankton composition on fish production in ponds was investigated in six fish farms for eight weeks. The physicochemical parameters investigated were temperature=25-30 plus or minus C, transparency=0.45-0.57m, dissolved oxygen=3.0-10.9mg/l, pH=6.0-7.7, dissolved carbon dioxide=5.46-28.3mg/l, total alkalinity=44.37-80.0ppm, chemical oxygen demand=31.88-72.18mg/l and biological oxygen demand=0.66-48.34mg/l. Plankton composition varies and was made of four families of phytoplankton namely: Cyanophyceae, Chlorophyceae, Dinophyceae and Diatomida; and four families of zooplankton viz: Protozoa, Rotifera, Copepoda and Dinoflagellates. Farm 1 and 6 recorded the highest average weight of about 1.0kg and average total length of about 40.0cm for the two fish species. This study showed that fish yield was dependable on the quality and management of pond water characteristics

Small Indigenous Freshwater Fish Species: their Role in Poverty Alleviation, Food Security and Conservation of Biodiversity, 23-25 February 2010, Central Inland Fisheries Research Institute, Barrackpore, Kolkata, West Bengal. Workshop report

This is the report on the workshop on “Small Indigenous Freshwater Fish Species: Their Role in Poverty Alleviation, Food Security and Conservation of Biodiversity”, organized by the International Collective in Support of Fishworkers(ICSF) in collaboration with the Inland Fisheries Society of India (IFSI). The workshop was a forum for exchange of views on the role of small indigenous freshwater fish species (SIFFS) in enhancing rural food supply and livelihood security, and in conserving biodiversity. The workshop also discussed the socioeconomic and cultural contexts for the culture and capture of SIFFS, and how to enhance access—especially for women—to better incomes, livelihoods and nutritional security, through appropriate policy spaces. This report provides a fresh focus on SIFFS, usually regarded as ‘trash’ fish. It urges scientists, researchers and decisionmakers to develop policy and legislative measures to ensure the conservation and promotion of SIFFS, both in capture- and culture-fisheries systems. This report will be useful for fishworker organizations, researchers, policymakers, fish farmers, members of civil society and anyone interested in fisheries and livelihoods. (PDF contains 86 pages)