Population Genetics and Essential Habitat of Snook in South Texas

Snook Centropomus spp. were an important commercial fishery is South Texas until the population crashed in the late 1930's. As snook numbers increase again in South Texas, biologically pertinent information is needed for the proper management of this growing fishery. Two important questions are: 1) what is the genetic structure of snook, and 2) are snook breeding in Texas waters? Currently, such information does not exist. As part of a larger study, the goal of this project is to provide important baseline genetic data for snook in South Texas. Samples from adult snook and young-of-the-year (YOY) were collected and analyzed for 10 species specific microsatellite markers using standard population genetic techniques and statistics. A sibship analysis will be performed on YOY to determine if they could have been produced by local adults, indicating a local breeding population. This project will also utilize geographic information system (GIS) methods to determine areas of high genetic diversity using the "Landscape Genetics GIS Toolbox" and indicate if there are clusters of siblings, and if those clusters are genetically distinct. With the results of this ongoing study, the utility of GIS maps will allow managers to locate areas of high genetic diversity and possible essential habitats.