Habitat Distribution and Diet Analysis of Two Sympatric Species of Balistes in the Western Gulf of Guinea.

The study was conducted during R/V Dr. Fridtjof Nansen survey 2005 in the Western Gulf of Guinea. A total of 165 station trawis were taken along the Western Gulf of Guinea from Nigeria-Benin border to Côte d'Ivoire-Liberia border. Of the 165 trawls 23 hauls yielded triggerfish. The study sought to find the distribution, depth range and diet preferences of Balistes capriscus and Balistes punctatus L. after two decades of their apparent disappearance in the area. The species show habitat overlap in the Western Gulf of Guinea. B. capriscus occur at 23 - 60 m depth, whereas B. punctatus occur at 22 - 32 m depth range from Benin to Côte d'lvoire. The gut analysis of B. capriscus and B. punctatus indicates that both triggerfish species are more planktivorous at juvenile stage (12.0-21.9 cm size class) and more benthivorous at later stage in life. It suggests there could be competition for food resources between the two fish species. However, it appears B. capriscus is better adapted in terms of benthic life as the species occurs at deeper depth of coastal waters and therefore, better selected for benthic feeding. [ABSTRACT FROM AUTHOR]