Assessment of Marine Megafauna in artisanal gillnet and longline fisheries in Kenya

Globally, populations of marine megafauna continue to decline because of factor such as overfishing, use of their by-products, and capture as bycatch in various fishing sectors. Specifically, bycatch is one of the major... [ view full abstract ]

Globally, populations of marine megafauna continue to decline because of factor such as overfishing, use of their by-products, and capture as bycatch in various fishing sectors. Specifically, bycatch is one of the major threats to marine megafauna (elasmobranch, marine mammals, and sea turtles) in the Western Indian Ocean (WIO) placing them at a high risk of depletion. The challenge is further exacerbated by lack of information on the magnitude of bycatch in artisanal, commercial, and semi-industrial fisheries. Consequently, there are insufficient measures to reduce incidental capture of sea turtles, elasmobranch, and marine mammals at national and regional level.

This first-time regional project assessed target and bycatch of megafauna from artisanal gillnets and longlines in the WIO. In Kenya, the distribution of bycatch events was evaluated using catch data, seasonality, and the lunar cycle from 8 landing sites between 2016 and 2017. Our findings depicted a wide diversity in target and bycatch species composition. A total of 552 rays, 94 sea turtles, and 1303 sharks were caught in artisanal fishing gears. Notably, 66% of bycatch consisted of shark species which are considered as critically endangered and data deficient under the IUCN Status list. These findings emphasize the need for further research on the interactions of sharks and these fisheries. On a regional and global scale, the study addresses the existing gaps in information and data. This is significant in the formulation of guidelines for sustainable use and management of these species in Kenya, and the Western Indian Ocean.