Last updated on 22 October 2013
Giant tiger prawn was introduced around the 1990s in Nigeria from escapement of shrimp farms; is native of the Indian and Pacific oceans (Isebor, 2003).
The only available data for catches regard several species of shrimps and prawns in Nigeria, are not updated and are not species-specific (FAO, 2001). No stock assessment is conducted for Nigerian coastal shrimp species. A working group of the FAO-organized Fishery Committee for the Eastern Central Atlantic (CECAF) convenes to assess and discuss demersal species in the CECAF south region but data is insufficient to allow an assessment or the identification of trends (CII, 2002; Gillett, 2008; FAO, 2011).
Last updated on 22 October 2013
The Nigerian Institute for Oceanography and Marine Research conducts studies about shrimp fisheries (Anyanwu et al, 2011). Zabbey (undated) and Vincent-Akpu (2013) refer the lack of data for effective management in Nigerian fisheries.
As general precautionary advice for the three spp of coastal shrimp in Nigeria – Penaeus notialis, P. monodon and Parapenaeopsis atlantica -, FAO recommends not providing more fishing licenses until more knowledge about their status is available (FAO, 2011). This advice does not specifically consider P.monodon’ status as an introduced species however, and any potential control of this species will be complicated by the likely mixed-species nature of the fishery. The impact of this introduced species should be analysed (Zabbey, undated; Gillett, 2008).
Under FAO’s guidance for introduced species and following ICES’s Code of Practice (FAO, 1996), a contingency plan should be in place, establishing “corrective or mitigating procedures” and monitoring should be undertaken to identify potential negative effects, such as “disease, changes in predator-prey relationships, changes in competition, mixing of bad (maladapted) genes, and habitat modification” (FAO, 1996).
Last updated on 22 Oct 2013
There are Maximum Sustainable Yield (MSY) estimates and Catch per Unit Effort (CPUE) references points but for other coastal shrimp species as a group and prior to the arrival of Giant tiger prawn to the Nigerian coast (Ogbonna, 2001). No reference points are known to be defined for this stock.
Last updated on 8 October 2013
No assessment is known to be conducted of Nigerian coastal shrimp species (FAO, 2011). Possibly outdated reports mention an increase in abundance of Giant tiger prawn (Zabbey, undated; Gillett, 2008) but the status of the stock is not currently known.
As an introduced species, Giant tiger prawn’s abundance should be tracked and potential impacts on native species and on the habitat monitored. Management of this species to reduce any potential negative impacts may be impeded by the context of a likely multi-species fishery.
Last updated on 08 Oct 2013
The only available data regard catches of different species of shrimps and prawns in Nigeria. Nominal catches have been progressively increasing until the late 1990s to more than 50,000 tons, decreased to around 25,000 t in 2000 and since then have been increasing (FAO, 2001).