GUIASU, R. C. * ; DUNHAM, D. W. ; Univ. of Toronto, Toronto, Canada ; Univ. of Toronto, Toronto, Canada : The ecology, behaviour, and conservation of the vulnerable burrowing crayfish Fallicambarus fodiens (Decapoda, Cambaridae)

Fallicambarus fodiens is a semi-terrestrial, burrowing crayfish species, whose entire Canadian distribution is restricted to only a few wetlands in southern Ontario. This species is now vulnerable in Canada, due to its small initial range and the on-going destruction of its habitat. The probability of the disappearance of additional northern populations of this species remains high, despite some recent habitat restoration efforts. Unlike the surface water crayfishes, F. fodiens can survive away from permanent waters. This species digs tunnels in the mud and builds mud chimneys above the tunnel openings. Laboratory studies have shown that F. fodiens can distinguish between very similar-looking conspecific-built and human-made mud chimneys, based mainly on chemical, and possibly also tactile, cues. Visual cues may also be important in attracting these crayfish to clusters of chimneys from a distance. F. fodiens individuals prefer to move into, or burrow beside, previously constructed conspecific chimneys. These chimneys may function as signposts, attracting new burrowing crayfishes to an existing colony. The burrowing crayfish can share their burrows with conspecifics, as well as other species such as some salamanders. These semi-terrestrial crayfish appear to be considerably less aggressive than the solitary surface water crayfishes. Studies on the ecology and behaviour of this little-known species can assist the conservation and habitat restoration efforts.