Effects of food and shell cues on mating in the hermit crab Clibanarius vittatus

Abstract

In hermit crabs, Clibanarius vittatus, activities associated with foraging for food and searching for a different gastropod shell are incompatible with mating activities. We hypothesized that due to the short mating season that mating would have priority over feeding or shell seeking. We compared the mating activities of groups of crabs in the absence of food and shell cues to mating activities of groups of crabs presented with food cues, shell cues, or a combination of food and shell cues. We measured the number of minutes of precopulatory behaviors executed and the number of pairs formed in these groups during 60 minutes periods.Comparison of mating activity in the presence and absence of shell availability cues supported our hypothesis. Shell availability cues had no effect on the number of pairs formed or the number of minutes of precopulatory behaviors. However, responses to food cues did not support the hypothesis. Food cues from high quality food very significantly decreased both the number of pairs formed and the number of minutes of precopulatory behavior executed. This was true for both food cues alone or in combination with shell-availability cues. The dominance of food-related activities over reproductive activities was surprising given the short mating season of C. vittatus at the latitude tested.