SUMMARY
Arnold Ortmann, one of the nations first crayfish biologists, conducted crayfish surveys in the late 1800’s and early 1900’s across western Pennsylvania. Unique for the time was Ortmann’s inclusion of primary burrowing crayfishes. Primary burrowing crayfish utilize subterranean burrows for all facets of their ecology, and are rarely encountered outside their burrows. Urbanization, extractive industries, and the genesis of industry have all occurred across western Pennsylvania since Ortmann’s initial surveys. We visited all of Ortmann’s historic sites to determine if burrowing crayfish still occur throughout the region following the past century of environmental change. Furthermore, crayfish have been recognized recently as one of North America’s most imperiled group of animals. Resultants of this, our efforts will lead to the determination of conservation baselines for each burrowing crayfish species occurring in the region.