Meeting Abstract

82.2  Thursday, Jan. 7  Does this color make my claws look phat? Evaluating claw color preferences in male blue crabs, Callinectes sapidus> BALDWIN, J.L. *; JOHNSEN, S. ; Duke University; Duke University jlb54@duke.edu

The blue crab, Callinectes sapidus, relies partially on color cues to determine an appropriate mate. In our previous work, we found that male blue crabs prefer females with red claws to those with claws modified to be white or black. Additionally, our results demonstrating the blue crab’s ability to discriminate red from an isoluminant black suggest that blue crabs are capable of color vision. Here, we have extended the study of blue crab color vision in relation to female claw color variations. Female blue crab claws vary in color from pale orange to deep red; and while no correlations between claw color and quality exist, it is possible that claw coloration serves as a sexual cue. In this study we presented male blue crabs with a choice between a photograph of a female with red claws and a photograph of a female with orange claws. The brightness of one orange hue was adjusted to create several variations of light to dark orange. Each orange variation was presented along with the red clawed photograph in binary choice tests. Male preferences were scored according the number of sexual displays made towards each picture. The results will be discussed in relation to blue crab color vision and the likelihood of female quality evaluation based on claw color.