Distribution of the Rusty Crayfish (Orconectes rusticus) and the Northern Clearwater Crayfish (Orconectes propinquus) in the Western Lake Erie Basin
Orconectes rusticus (Rusty Crayfish) is a species of crayfish invasive in many regions, including the Great Lakes. Where established, O. rusticus has displaced many native species of crayfish and induced changes in macrophyte, macroinvertebrate, and vertebrate communities. Collections by Dr. Ken Baker from 1997 to 2003 (Heidelberg University) recorded a continuing presence of the native Orconectes propinquus (Northern Clearwater Crayfish) in the western Lake Erie Basin (particularly South Bass Island and Kelleys Island). This study aimed to investigate 1) the native O. propinquus is still present in the area, 2) map a distribution of the two species’ ranges, and 3) identify any factors that may be contributing to O. propinquus’ continued presence in the system. We sampled crayfish via snorkeling around sites visited by Dr. Baker, recorded water chemistry data at each site as well as in mainland tributaries of Lake Erie, and examined specimens for possible hybridization in character states. O. rusticus and O. c.f. propinquus distributions were roughly in line with the distributions from Dr. Ken Baker’s collection. Around South Bass Island, O. rusticus was focused in the bay area while the hybrid of O. rusticus and O. propinquus was found on the outer edges of the island. Around Kelleys Island, O. rusticus was found on the shorelines and O. c.f. propinquus was found in deeper water. The species did not show significant preference toward the measured water chemistry metrics. We were able to confirm continued apparent hybridization. Further studies are needed to determine the reason O. c.f. propinquus is holding ground in the region.