Fishery and Wildlife Biology, Colorado State University, Ft. Species richness is localized in the southeastern states, the Gulf coastal plain, and the Ozark and Quachita Highlands where late-summer water temperatures can be stressful for crayfish.
Some species are tolerant of environmental extremes and disperse widely.
Others are limited in their geographical distributions and may be threatened by pollution or when invasive species are introduced. Many surface-dwelling and subterranean crayfishes may be subject to declining populations as a result of environmental changes associated with groundwater pumping, pollution, and reduced stream flows. Considering predictions from regional climate models, it is important to understand how different endemic species respond to intense drought, increased salinity, and warmer temperatures. Long-lived burrowing species are more likely to persist and to minimize exposure to predators in contracting habitats during extreme droughts. Pesticides and heavy metals may also have increased impacts in warmer, shallower habitats.