Hotspots of Freshwater Mussel Biodiversity in East Texas

Texas contains a high diversity of freshwater mussels (family Unionidae), primarily in the eastern portion of the state.  However, with increasing population size and water demands, east Texas rivers are threatened with habitat alteration as a result of reservoir development. In order to identify areas of high biodiversity, we incorporated regional abiotic data in Geographic Information Systems (GIS) and the ecological niche modeling software MAXENT. We modeled habitat suitability of 30 mussel species throughout the eastern part of the state. Because host fish are important biological determinants of mussel distributions, we used MAXENT to predict areas of suitable habitat for fishes and examined the relationship between areas of potential habitat suitability between fishes and mussels.  Results indicate that the upper Neches River within the Big Thicket National Preserve contains the highest quality habitat for the greatest number of species. The preserve is surrounded by bottomland hardwood forests mostly unaffected and unaltered by anthropogenic activities, making it suitable habitat for multiple unionid species. Other hotspots represent additional areas that have highly suitable habitat for unionid species, so protection efforts should be focused on these places. Our results will prove useful for the creation of conservation strategies for this imperiled fauna.