Small-scale artisanal coastal fisheries provide over 80% of household income hence plays a vital role in food security of developing countries. However, they are frequently undervalued and characterised as multi-gear and multi-species, such as in Kenya’s artisanal fisheries. Further, problems due to over-fishing and destructive fishing methods are currently widespread and broadly linked to impoverished coastal communities.
Our research in 2016 published in the Journal Fisheries Research sought to determine the sustainability of artisanal fishing gears, deployment, effort and definitions of the gears.
Two hypotheses were tested:
• Artisanal fishery catch rates are in decline and stocks are overfished;
• Populations of reef fish are declining.
A series of meta-analyses were used to combine a range of fish and fishery population descriptors and parameters; catch rate trends; species composition, yield, juvenile retention rates of different gears and fish population abundance were examined to understand gear impacts and sustainability at current fishing levels.
The results showed that Kenya’s coral reef fishery catch rates have declined 4-fold since the mid 1980s and species diversity in catches has declined to 2-3 species in the top 65% bracket. Management changes are proposed to ensure these fisheries continue to provide livelihoods and food security on the Kenyan coast. We also report that fully protected sites (Marine Parks) have higher reef fish population densities than elsewhere but over decades even these have declined.
We combined a range of fishery and fish population descriptors to analyze Kenya’s coral reef fish and fisheries over a 20-year period from the 1980s, to determine the sustainability of current fishing levels and provide recommendations for management. Fishers report over 13 different artisanal fishing gears but there are only data for the five widely used gears.
Gillnets are particularly poorly reported – as one gear yet their sub-types span >40cm in mesh size. Average catch rates declined 4-fold from the mid1980s to the 1990s and then stabilized, likely maintained by shifting proportions of species in the catches.
Patterns in fish population densities over time show Marine National Parks have helped increase densities of emperors and sweetlips and reduced the decline in densities of parrotfish and surgeonfish, but National Reserves have had no positive effect.
We suggest that the National Parks, which are No Take Zones (NTZs), and the fisheries regulations inside and outside of Reserves are inadequate for maintaining or restoring reef fishery target families under current levels of fishing pressure.
To safeguard the future of Kenya’s coral reef fish populations and people’s livelihoods and food security,the study recommends a combination of species–specific management options,changes in and enforcement of gear regulations, and many more NTZs through efficient Reserves and community LMMAs.
Such mechanisms should improve fish populations and coral reef resilience to the combined and interacting effects of fishing and climate.