Decadal trends in CPUE in Kenya


Kenya’s population has more than doubled in 30 years. From 18 million in the late 1970s it is set to reach 55 million by 2050. Finite marine fish populations cannot sustain this demographic pressure. Research and analysis of long term datasets on nearshore fishery catches and fish populations suggest Fishing netthat the shallow water demersal fish stocks are under significant and unsustainable pressure. The effects of artisanal fishing gears used by local fishermen in Kenya were evaluated to understand their impacts on coastal fishes and review management practices. There are 14 different gears used by Kenya’s artisanal fishermen (link to fishing gear book), five of which are widespread and commonly used (Figure 1).

We collated data from over 25 published studies to examine long-term trends in these five commonly used gears and to assess their ecological impacts.

Tremendous changes in the catch rates have occurred in the Kenya’s marine artisanal fishery. Catch per unit effort (CPUE) dropped dramatically since the 1980s from around 13.7 kg/fisher/trip to 3.2 kg/fisher/trip in the mid-90s (figure below), representing a four-fold decline in catch rates. However, from the mid 1990s to 2006 CPUE has remained relatively stable, across the different gears – an indication of sustainable levels of fishing.

Kenya fishing gears

Average catch per unit of effort (kg fish/fisherman/day) for each of the 5 common gears.

Illegal gears: catch rates per fisherman differed consistently by gear, with spear guns always the highest and beach seines the lowest. These gears are both illegal under the State of Fisheries Department regulations. Understanding the differences between these gears are essential in enforcing or revising regulations. For instance beach seine crews could be advised to use basket traps or hand-lines to gain more income. Young men tend to reject the traditional basket trap, but its catch rates were consistently higher than gillnets.

SpeargunJuvenile catch rates: an average juvenile retention rate of 50 % was reported across all gears with the highest being for beach seines (68%) and the lowest by spearguns (38%).

Spearguns: We found few reasons to support the illegal status of spearguns: the lowest juvenile retention rates, no by-catch and one of the most affordable for a young fisherman.