Southwest Atlantic: known only from two records from Brazil in the southwest Atlantic, both from Paraná State (Barletta et al. 1989, Charvet 1995, Gomes and Gadig 2003, P. Charvet-Almeida pers. comm.). The first specimen was caught in coastal waters of Baía de Paranaguá (Barletta et al. 1989) and the second from off Superagui, close to the border with São Paulo (Charvet 1995, P. Charvet-Almeida pers. comm.).
Habitat and Ecology
Life History and Behavior
- Breder, C.M. and D.E. Rosen 1966 Modes of reproduction in fishes. T.F.H. Publications, Neptune City, New Jersey. 941 p. (Ref. 205)
IUCN Red List Assessment
Red List Category
Red List Criteria
The northwestern African shelf is considered fully exploited (Zeeberg et al. 2006) and ranks amongst the most intensively fished areas in the world. Foreign industrial freezer trawlers targeting small pelagic fish (Sardinella, sardine, and horsemackerel) operate nearly year-round on the shelf off western Africa, with some of these vessels amongst the largest fishing boats in the world (Zeeberg et al. 2006).
Zeeberg et al. (2006) examined the bycatch of megafauna in European trawlers operating off Mauritania between 2001 and 2005. They demonstrated considerable bycatch of "manta rays" which most probably includes Mobula rochebrunei (note that while the authors refer constantly to "manta rays", figure 3 in their manuscript clearly shows an entangled Mobula, and subsequent communications with the primary author indicated that they observed both Manta birostris and Mobula species). Zeeberg et al. (2006) extrapolated from their results that some 120-620 "manta rays" are captured annually by the Irish and Dutch trawl freezer-trawl fleet. Actual bycatch levels off Mauritania will be considerably higher are there are also Russian, Icelandic and Lithuanian trawlers operating in the same areas.
The subregional workshop for sustainable management of sharks and rays in West Africa, 26-28 April 2000 in St Louis, Senegal (Anon. 2000) noted the high threat to sharks in the west African region and a noticeable decline in the CPUE of total sharks and rays. Increased targeting of sharks and rays began in the 1970s, when a Ghanaian fishing community settled in the Gambia and established a commercial network throughout the region, encouraging local fishermen to target sharks for exportation to Ghana. By the 1980s many fishermen were specialising in catching sharks, resulting in a decline in overall shark populations (Walker et al. 2005).
Mobulid species appear to be particularly susceptible to overfishing as their fecundity is among the lowest of all elasmobranchs (with litter sizes of typically only one pup and an assumed gestation period of 1-3 years (White et al. 2006).
- IUCN 2006 2006 IUCN red list of threatened species. www.iucnredlist.org. Downloaded July 2006.
Elasmobranch fisheries are generally unmanaged throughout the range of this species, and attempts to regulate fisheries in these regions would greatly improve conservation of M. rochebrunei and other chondrichthyans.
The development and implementation of management plans (national and/or regional e.g., under the FAO International Plan of Action for the Conservation and Management of Sharks: IPOA?Sharks) are required to facilitate the conservation and sustainable management of all chondrichthyan species across the regions where this ray occurs.
The vulnerability of mobulids and increasing catches requires urgent international conservation measures. These will need to focus on harvest and trade management.
Relevance to Humans and Ecosystems
- Schneider, W. 1990 FAO species identification sheets for fishery purposes. Field guide to the commercial marine resources of the Gulf of Guinea. Prepared and published with the support of the FAO Regional Office for Africa. Rome: FAO. 268 p.
To request an improvement, please leave a comment on the page. Thank you!