Crayfishes of the Apalachicola Ravines, Northern Florida: A Search for the Fireback Crayfish,Cambarus pyronotus

Abstract

The series of steep, wooded ravines along the eastern side of the Apalachicola River in Gadsden and Liberty counties, FL, is recognized for its rich biodiversity. Little recent information is available on crayfishes of this unique ecosystem. During surveys conducted from 1939–1941, 5 taxa, including one undescribed species (now Cambarus pyronotus [Fireback Crayfish]), were recorded. No crayfish studies were conducted in the Apalachicola Ravines in the ensuing 60 years, and the conservation status of C. pyronotus remained unknown. From June 1999–February 2002, we surveyed the Apalachicola Ravines to determine distributional limits and stream-by-stream occurrence of C. pyronotus and evaluate its conservation status in relation to the regional system of protected lands. We recorded 8 species of crayfishes, including 4 primary burrowers and 4 aquatic species. Members of each of these 2 groups exhibited distinct microgeographic and microhabitat selection patterns, with several species showing non-overlapping microdistributions. We documented C. pyronotus from only 12 of 29 stream drainages surveyed, all within the middle region of the survey area, for a total range estimate of about 80 km2. Most of the inhabited streams within this small range occur on protected lands and include multiple habitable branches.