Shelter Use in Cambarus robustus, a Surrogate Species for the Federally Listed Cambarus callainus and Cambarus veteranus

Abstract The Big Water Crayfish, Cambarus robustus, is native to several eastern U.S. states and Ontario, Canada. Cambarus robustus possesses several traits that make it a potential surrogate for federally listed species, such as the Big Sandy Crayfish, Cambarus callainus, and the Guyandotte River Crayfish, Cambarus veteranus. Basic husbandry information, like optimal temperature, and shelter requirements, have yet to be investigated for most Cambarus species. Therefore, to create a protocol for shelter requirements and preferences for federally listed Cambarus species, we conducted a shelter preference study with C. robustus. Thirty-one crayfish were placed in two treatments where opportunities to burrow underneath natural shelters, clear acrylic shelters, or tinted acrylic shelters were presented. Clear and tinted acrylic shelters are beneficial for investigators as they allow for monitoring of behavior and health without disrupting the crayfish. Each of the two trials lasted 24 hours and were video recorded to monitor behavior and shelter use. Our results suggest that C. robustus will use all shelter types, although natural shelters were occupied more frequently than acrylic shelters. Sex and size had minimal or no influence on shelter use. Future studies should continue to investigate husbandry and rearing techniques for Cambarus spp. and other species where propagation and head-starting efforts will commence.