Elasmobranch exploitation in Africa

Abstract

The impact of fisheries on elasmobranchs in Africa is not well documented. Available data suggest that there are no large shark fishing nations (> 10000 t year-1), reported landings for 1994 being around 39 000 t. This value is believed to be a underestimate, because of a lack of data on catches and landings from the various different fishing methods and the large number of nations fishing in African waters. Existing data are mostly linked to industrial fisheries, although the artisanal sector could be responsible for substantial catches. Landed by-catch and discard rates of elasmobranchs are unknown for most commercial fisheries targeting teleosts. Limited data sources allowed only crude estimates of catch. The artisanal fishery is calculated to land a minimum of 20 000 t of sharks, whereas the industrial trawl sector is likely to catch 23 000 t. A conservative estimate for the African continent and the surrounding islands is ~95 000 t. The quality of catch-and-effort data for both commercial and subsistence fisheries on the African continent needs to be improved, and the by-catch issue should be investigated through trained onboard observers.

Size of catch, reproduction and feeding of the small-eye smooth-hound, <em>Mustelus higmani</em> (Carcharhiniformes: Triakidae), in Margarita Island, Venezuela

“…Springer and Lowe (1963) reported similar findings, with a catch of a neonate (21.3 cm TL) smaller than the largest recorded embryo (24 cm TL). This observation of neonate catches is also reported in shark fisheries from Africa and the Mediterranean Sea (Kroese andSauer 1998, Saidi et al 2008).…”

The traditional shark fisheries of southwest Madagascar: A study in the Toliara region

“…This figure greatly exceeds the estimated mean annual catch of 500 kg of elasmobranches per km of coastline in Madagascar stated by Kroese and Sauer (1998) in their review of African elasmobranch fisheries, a worrying underestimate when you consider that there are at least 14 other similar villages that exploit sharks within 100 km of the study area (den Haring, pers. commun.).…”

Spatial ecology of juvenile lemon sharks (Negaprion brevirostris) in tidal creeks and coastal waters of Eleuthera, The Bahamas

“…Globally, sharks and other apex predatory fish species are in decline (Baum et al 2003;Christensen et al 2003;Baum and Myers 2004), largely as a result of life history characteristics that make them vulnerable to fisheries exploitation (i.e., slow growth, late maturity and low fecundity; Walker 1998; Kroese and Sauer 1998;Stevens et al 2000). However, some shark species are also facing threats from habitat alteration associated with coastal development (Manire and Gruber 1990;Camhi et al 1998).…”