Artisanal fisheries catch highlights hotspot for threatened sharks and rays in the Republic of the Congo

Abstract

Global catch rates of sharks and rays from artisanal fisheries are underreported, leading to a lack of data on population status. This forms a major barrier to developing effective management plans, such is the case in Central and West Africa. Over 3 years, we undertook the first systematic quantitative assessment of sharks and rays landed by an artisanal fishery in the Republic of the Congo. During 507 sampling days (mean 14 surveys per month), we recorded 73,268 individuals. These comprised 42 species, of which 81% are considered at an elevated risk of extinction. Landings were dominated by immature individuals, especially for species of conservation concern. Presence of species thought to have largely disappeared from the region such as the African wedgefish (Rhynchobatus luebberti) and smoothback angelshark (Squatina oculata) suggest Congolese waters are a potential stronghold for these species—warranting increased protection. We identified seasonality of catch within years, but not across years. Both inter- and intra-annual trends varied by species, signifying annual fluctuations in catch of each species but consistent catch of all species year-on-year. Analysis showed increased catch between the short-wet and the long-wet, and the long-dry seasons (January–February and August–September). Lowest catch was shown to occur during the short-wet and the short-dry seasons (October–December), which may provide an opportunity for seasonal closures or gear restrictions.