Den selection by the spiny lobster Panulirus argus:: testing attraction to conspecific odors in the field

The spiny lobster Panulirus argus is a model organism in laboratory studies of olfaction, but Little is known about how these animals use odor cues in the field. Juvenile spiny lobsters aggregate in dens, a behavior that may be mediated via chemical attraction to conspecific odor cues. To test this hypothesis, we developed a submersible system capable of perfusing odors of live spiny lobsters into experimental den sites within a natural reef setting. Using this system, we tested the effect of conspecific odor on aggregative behavior by measuring the frequency of attraction of lobsters to den sites perfused with either conspecific odor or natural seawater. We found that juvenile spiny lobsters were attracted preferentially to dens perfused with conspecific odor: scented dens captured an average of 2.0 lobsters den(-1) k(-1) and control dens captured an average of 0.60 lobsters den(-1) wk(-1). However, the distribution of the numbers of lobsters attracted to dens each day did not depart significantly from that predicted by a Poisson distribution, indicating that each capture was independent of all others. Our data thus suggest that the odor of conspecifics can act as an aggregation cue by spiny lobsters under field conditions, even in the absence of other sensory cues.