KRAUS-EPLEY, K.E.*; MOORE, P.A.: The Effects of Antennal Lesions on Orientation Behavior of the Crayfish, Orconectes rusticus

Numerous animals use chemical cues within their environments to execute various behaviors. One of these behaviors is orientation to a food source. Crayfish, in particular, can orient to food sources under a number of different conditions. It has not been determined, however, if and how these animals with complete or partial impairment of their chemosensory appendages can successfully locate a food source. To determine the effects of impairment, the orientation patterns of crayfish with various degrees of antennal lesions were examined. Analysis of results confirmed that crayfish successfully locate distant food sources using chemotaxis and must have both antennae to do so. It appears that crayfish use the spatial information from bilateral sampling to successfully orient. Animals using both antennae exhibited increased walking speed and speed to source, decreased heading angle towards the source, and a more linear path than animals with the use of one or neither antenna(e). It was also found that other chemosensory appendages, including chelae and walking legs, play a lesser role in orientation than may have been previously thought.