IMPACT OF CLIMATE CHANGE ON FISH ECOLOGY IN THE CROSS RIVER ESTUARY, SOUTHERN NIGERIA 0 0
DOI:
https://doi.org/10.83374/jesber.vol1no2.97Keywords:
Climate change, Fish ecology, Fish stock, Multiple correlation analysis, Artisanal fisheries, Cross River Estuary, Southern NigeriaAbstract
Fish ecology, the set of processes governing the distribution, abundance, and interactions of fish and their environment, is highly sensitive to climatic conditions, yet the specific pathways through which climate change affects artisanal fisheries in the Cross River Estuary, one of the largest estuaries along the Gulf of Guinea, remain poorly documented. This study examined the impact of climate change on fish ecology in the Cross River Estuary, focusing on fish yield, species distribution, fish stock, seasonality in production, and spawning grounds. Fifty years (1965-2014) of annual rainfall, temperature, relative humidity, and wind speed data were obtained from the Nigerian Meteorological Agency, Margaret Ekpo International Airport, Calabar, and analysed using mean, standard deviation, standardised anomaly, and coefficient of variation to characterise temporal climatic variation. A multistage sampling procedure was used to select 15 of 64 fishing communities and identify permanent fishing households whose heads were aged 40 years and above with at least 20 years of fishing experience; questionnaires were administered to 1,362 fishers, of which 1,291 were validly completed and analysed using descriptive statistics and Multiple Correlation Analysis. Results showed that climate change increased the proportion of juvenile fish in the estuary (44.0% of respondents), reduced the species composition of fin fishes (24.9%), altered the time of peak fish abundance (35.7%), reduced fish availability during the wet season (33.0%), and increased water currents at spawning grounds (24.2%). Multiple correlation analysis showed that rainfall, temperature, relative humidity, and wind speed jointly accounted for 29.6% of the variation in ecological problems facing artisanal fishers (R = .54, R² = .296), with temperature showing the strongest individual partial association (r = .273). The study concludes that climate change is measurably altering fish ecology in the Cross River Estuary and recommends fisher enlightenment on climate adaptation and restriction of mangrove logging to protect fish spawning habitats.Downloads
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