Manatee Capture and Release: First Documentation in Rogolié River Wetland, Gabon | InformativeBD

Christy Achtone Nkollo-Kema Kema, Judicael Régis Kema Kema, Igor Akendengue Aken, Mariella Nzambe,  Anaclet Mombo, and Christophe Roland Zinga Koumba, from the different institute of the Gabon. wrote a research article about, Manatee Capture and Release: First Documentation in Rogolié River Wetland, Gabon. entitled, First documentation of the capture and release of a manatee in the Rogolié River wetland (Ntoum, Gabon). This research paper published by the Journal of Biodiversity and Environmental Sciences (JBES). an open access scholarly research journal on Biodiversity under the affiliation of the International Network For Natural Sciences | INNSpub. an open access multidisciplinary research journal publisher.

Abstract

A large number of marine mammals are seriously threatened by fisheries. Although the issue of by-catches in fisheries is a major threat to marine mammals, it has not yet been tackled in a concrete way in Gabon. Artisanal fishing accounts for 95% of fishing activity. Their impact on vulnerable megafauna can therefore be significant, either as bycatch or as target species. However, detailed information on the composition of fisheries catches is limited because of a lack of monitoring and reporting due to limited financial and logistical capacity. The aim of this paper is to document a rare phenomenon of the release of an African manatee (Trichechus senegalensis) caught in fishing nets at the mouth of the Rogolié River in the Gabon estuary.

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Introduction

Of all sirenians species the West African manatee (Trichechus senegalensis) is the least well known biologically (Reynolds and Odell 1991). The species is considered vulnerable by the IUCN (Keith Diagne, 2015) due to the persistence of a wide range of threats, primarily of human-induced. This species occurs in most of the coastal marine waters, brackish estuaries, and adjacent rivers along the West African coast from southern Mauritania (16°N) to the Cuanza and Longa Rivers in Angola (9°S) (Dodman et al. 2008; Perrin 2001; Powell 1996; Grigione 1996; Nishiwaki 1984; Husar 1978; Robinson 1971; Blancou 1960; Beal 1939). Gabon may have one of the highest densities of Manatees remaining in Africa (Nkollo 2022; Powell 1996). The decline of the Trichechus senegalensis population has been largely attributed to hunting and incidental capture in fishing nets (Dodman et al. 2008; Blancou 1960; Cadenat, 1957).

Bycatch in fishing gear is also a major threat in all African countries, and even when caught alive, most manatees caught incidentally are not released, but killed (Nkollo 2017; Mbina 2001).

The aim of this note is to document the phenomenon of accidental captures and rescue efforts for the African manatee, a vulnerable species. We believe that the lessons learned from this event can be beneficial to manatee conservation stakeholders and can contribute to the development of better manatee release practices.

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