The demand for fish in Nigeria is still not met, despite having a domestic production estimated at about 800,000 metric tonnes. The demand stands at about 2.1 million metric tonnes per year. There is a shortfall of about 1.3 million metric tonnes. To solve this problem Nigeria has turned to fish importation while several other policies are being put in place by successive administrations to improve on local production. However, none of the efforts has been successful so far. The aim of this paper is to assess the potentials of offshore aquaculture within the exclusive economic zone (EEZ) of Nigeria with the view of meeting the fish demand of Nigerians. The paper develops a framework for the operation of offshore aquaculture. The implications of climate change on offshore fish production along the coastal area were highlighted. Strategies and policy measures needed to combat the challenges facing offshore aquaculture in order for it to live to its full potentials in protecting the living welfare of the fishermen and ensuring food security are also discussed.

Catfish consumption has risen over the last 2 decades with its popularity more pronounced in a cosmopolitan, commercial and industrial region like Lagos state. However, there is a need to measure the level of anthropogenic induced impacts on the safety level of fish production within this environment for human consumption. This research determined the level of trace metals bioaccumulation within the three senatorial districts of Lagos state. A total of nine (9) fish farms (three from each senatorial district) operating earthen ponds were randomly selected. Water samples from the farms were also collected and analyzed for heavy metals. Fish samples were smoked before analysis. The trace metals such as chromium, cobalt, iron, lead, aluminum and copper and manganese was analyzed using Atomic Absorption Spectrophotometer. The result of the trace metals were 0.07 – 0.13 mg/kg (lead), 0.01 – 0.02 mg/kg (chromium), 6.75 – 7.77 mg/kg (iron), 3.05 – 3.89 mg/kg (manganese), 0.05 – 0.07 mg/kg (copper), 0.00 – 0.01 mg/kg (cobalt) and 0.00 – 0.01 mg/kg (Aluminum). Statistically, there is no significant difference (P>0.05) among the various locations except for aluminum. The trace metal levels were below the tolerable or allowable level for fish food as recommended by Food and Agricultural Organization or World Health Organization, Median international standard, European Union, United State Environmental Protection Agency and Water Pollution Control Legislation for fish food. The detection of lead above standard in the water suggests the need for frequent monitoring of the water quality and fish food to prevent possible toxicity that could arise from the consumption of the fish food from the study area.

Water samples were taken from four different sources (Well, stream, borehole and treated). Chemical and bacteriological analyses of samples carried out to determine, lead, cadmium, manganese, aluminium, sodium, bacteria counts and isolates revealed that mineral elements were significant (P<0.05) among water samples from four different sources except for lead. Apart from the treated water sample; results of the bacteria counts and isolates revealed that the water samples contained some levels of bacteria species (Klebsiella oxytoca, Pseudomonas aeniginosa, Bacillus subtilis, Streptococcus faecalis and Enterobacter cloacae).Then an experiment was carried out to investigate the effects of the water sources on broiler performance and carcass parameters. Except for the birds on the treated water that had significant (P<0.05) weight gain among the water sources, generally, the performance indices were not significantly (P>0.05) affected by the treatments. Carcass parameters were not significantly (P>0.05) affected by the treatments except for the neck. Hence, this investigation tends to reveal that the outcome of the chemical and bacteria analysis of the water samples did not have significant (P>0.05) effect on broilers performance and carcass growth. Therefore, within the limit of this study; in terms of period and location, any of the investigated water samples is good for broiler consumption without any detrimental effect to their wellbeing.

The study examined the effect of abattoir effluent on some physico-chemical parameters and heavy metal content of Ta’jan River in Ogbagi Akoko, Ondo State. Water samples were taken once in October and November at seven different locations along the receiving water body at sampling points:S1, S0, S2, S3, S4, S5 and S6; S1 (10meters upstream of the point at which effluents enter the stream),S0 (point at which effluents enter the stream) S2 (10 meters downstream of the point of effluent discharge), S3 (20meters downstream of the point of effluent discharge), S3 (30meters downstream of the point of effluent discharge), S4 (40meters downstream of the point of effluent discharge), S5 (50meters downstream of the point of effluent discharge) and S6 (60meters downstream of the point of effluent discharge) along Ta’jan stream. The time of taking the samples were in the morning during slaughter hours.The samples were collected, preserved, and analysed in the laboratory using standard methods. Wastewater parameters analysed were dissolved oxygen, Temperature (TEMPT), conductivity (COND), salinity, turbidity, nitrate, sulphate, phosphate, pH, total suspended solid (TSS), total dissolved solid (TDS), and heavy metals, such as iron, lead, copper, and zinc. The downstream levels of most of the parameters were significantly (p<0.05) better than the discharge point. This suggests river Ta’jan has good recovery capacity.The findings can be useful in identifying the water quality problems and how to improve the water body when been diverted into fishponds or used for all other industrial or agricultural purposes in the community.

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