The Rusty Crayfish is a non-native, crayfish species that is native to the Midwestern United States. The Rusty Crayfish has been found in at least 21 counties within Pennsylvania, including York County, and populations have been recorded in parts of the lower Susquehanna River watershed. It is believed that the Rusty Crayfish was introduced throughout Pennsylvania via “bait buckets” introductions. The Rusty Crayfish have been found in a variety of habitats but seem to prefer warmwater habitats, which is good news for the cold-water Yellow Breeches.
Numerous studies show the negative impacts of the Rusty Crayfish on the ecosystem. They are known to out compete the native crayfish species for both habitat and predation. Rusty Crayfish are also known to carry a fungal agent (Aphanomyces astaci) which has to potential to infect other crayfish species. In addition to their effects on other crayfish species, the Rusty Crayfish may decrease sport fish populations, like the Walleye and sunfish.
Unfortunately, little can be done following the establishment of this species in watershed. Therefore, the primary goal of the Aquatic Invasive Species Control Plan is to prevent the introduction of this species into other watersheds.