Predicting the Distribution of Penaeid Shrimp Reveals Linkages Between Estuarine and Offshore Marine Habitats

Abstract

Marine fish and shrimp species are often dependent on estuarine habitats for juvenile or other early life stages, yet the effect of estuarine habitat availability has rarely been linked to the offshore, marine distribution of species. Penaeid shrimp are an estuary-dependent taxa that have global economic importance and are frequently cited as prey of fish. Species distribution models were developed for three penaeid species in the northern Gulf of Mexico, USA, with the objectives of modeling the distribution of species and testing the influ ence of multiscale predictor variables depicting oceanography, geography, geomorphology, and area of nearby estuaries and coastal wetlands. Fishery-independent trawl survey data of brown shrimp (Penaeus aztecus), white shrimp (Penaeus setiferus), and pink shrimp (Penaeus duorarum) were analyzed with boosted regression tree statistics. Species distribution models of catch per unit effort explained 30–45% of model deviance for brown shrimp and white shrimp; the presence/absence model of pink shrimp had an area under the curve statistic of 0.85 and overall accuracy of 83% correct. Oceanographic predictors had the greatest influence in each of the models, and the spatial distribution of each species was distinct based on these conditions. The marine distribution of all three penaeids was associated with nearby wetland area, and white shrimp were additionally associated with nearby estuary area. Geomorphology predictors were retained less often and were of low relative influence. Our findings demonstrate the importance of considering multiple spatial scales when identifying species-habitat relationships, including the influence of adjacent or nearby environments.