Linking shrimp recruitment and environmental variability in French Guiana
The shrimp fishery (Farfantepenaeus subtilis and F. brasiliensis) was the first fishery in value in French Guiana during the 1990s. However, two successive drops in recruitment in 1999 and 2006 led to decreases in stock and hence landings of shrimp. Recruitment levels are today at their lowest. Prior analyses suggest a minor influence of harvesting and fish predation on the failure in stock rebuilding. Environment instead appears to play a pivotal role here.
In a region where few oceanographic surveys have been carried out, remote sensing has proven a powerful tool to track variations in the environment. Series of water temperature, turbidity, suspended matters and chlorophyll a concentrations were analysed and compared to the series of shrimp recruitment in order to: 1) Detect the occurrence of temporal trends or potential regime shifts in waters off French Guiana, 2) Assess the relationships between these environmental factors and recruitment success of F. subtilis. While trends can be observed in some environmental factors, no clear link can be established between a single variable and the recent decline in shrimp recruitment.
Magraoui Amira, Baulier Loïc, Blanchard Fabian (2014). Linking shrimp recruitment and environmental variability in French Guiana. Johan Hjort Symposium on Recruitment Dynamics and Stock Variability 7-9 October 2014, Bergen, Norway. https://archimer.ifremer.fr/doc/00283/39398/