Direction orientation of the sand fiddler crab Uca pugilator (Bosc) in water: onshore escape response

When dislocated offshore at their home beach, sand fiddler crab displayed an escape response, in which they moved directionally in the onshore direction. This response probably functions for predator avoidance of an area containing predators. Male crabs correctly oriented in the onshore direction of the home beach in the presence of only celestial cues but were disoriented under cloudy skies. When exposed to slope, crabs moved in the upslope direction with the threshold slope being 3°. In a wave tank, crabs moved in the direction of wave travel. Crabs avoided a simulated landmark which was interpreted as avoidance of an approaching predator. -from Authors

Duke Scholars

Author Richard B. Forward Marine Science and Conservation