Use of GIS for the Study of Shrimp in Lake Nokoué

The purpose of this study is to contribute to a better understanding of the geographic distribution of Penaeidae shrimp in Lake Nokoué in Sô-Ava using Geographic Information Systems (GIS) to support the sustainable management of their ecosystems. In Lake Nokoué, Penaeidae shrimp are subject to unprecedented overfishing. To understand and subsequently reduce these pressures, a holistic view is necessary. GIS was used for this purpose. A geostatistical analysis was conducted on data regarding the quantities of shrimp caught from January to April 2012. An exponential variogram model without a nugget effect was obtained. The distribution maps show a decline in catch volumes preceded by an increase. The peak occurred in February, when up to 2.4 metric tons of shrimp were observed at Houédo-Aguékon. In every month, the areas of highest concentration remained Houédo-Aguékon, Ganvié2, and Vêkky. These areas are close to the shoreline (less than 100 m). The individuals of the captured species vary in size. The smallest is 2 cm long and weighs 1.6 g, while the largest is 13 cm long and weighs 16 g.