Ephemeral wetlands as significant habitat for threatened crayfish in Alabama, USA

While ephemeral wetlands contribute significantly to regional freshwater biodiversity, their role in supporting threatened and imperiled species of crayfish is not widely recognized. As the center of global crayfish biodiversity, the southeastern United States (US), and the state of Alabama (AL) in particular, are important focal areas where information is needed to develop understanding of habitat constraints determining the distributions of crayfish species. To this end, we documented crayfish species associated with ephemeral wetlands and associated wetland habitats that have been traditionally under sampled. Fifteen species of crayfish were documented among 96 survey sites. This assemblage included three Alabama state-listed Priority 1 species [Cambarellus diminutus Hobbs, Fallicambarus burrisi Fitzpatrick, Procambarus viaeviridis (Faxon)] and five Priority 2 species [Hobbseus prominens (Hobbs), Orconectes lancifer (Hagan), Procambarus evermanni (Faxon), P. leconti (Hagan), P. marthae Hobbs]. An undescribed species of Cambarellus (“sp. A”) was also documented, and will presumably be eventually designated a Priority 1 species in Alabama due to its restricted distribution and apparent endemism. Ten species of crayfish were documented from ephemeral wetlands, including four Priority 1 and 2 species [Cambarellus sp. A (presumed Priority 1 species), H. prominens, P. marthae, P. viaeviridis]. Most populations of Priority 1 and 2 species we documented are within the 100-year floodplain of the Black Warrior River. Ephemeral wetlands and associated wetland habitats within the floodplains of large rivers thus appear to be vital habitat for threatened and imperiled crayfish in Alabama. Our results suggest that future crayfish surveys should include sampling of these important but often overlooked habitats.