Personality and habitat segregation in giant sea anemones (Condylactis gigantea)

Animal personality is described as consistent differences in individual behavior across time or context, and may vary spatially. Bolder animals are more likely to migrate, grow slowly, or explore than shyer animals. Personality types within a population can also differ between discrete habitats or continuously across an environmental gradient. We examined the distribution of giant sea anemone (Condylactis gigantea) responses to disturbance across a continuous habitat gradient to determine whether anemones' habitat selection is explained by individual variation. On four different occasions we induced individual anemones to retract their tentacles by touching them with a model blue crab (Callinectes sapidus) and recorded the time for their tentacles to relax into their original state. We also recorded several environmental variables associated with each anemone. We found that individual anemones behaved in consistently different ways and that a combination of seagrass measurements and the number of close conspecifics, as well as their tentacle color, significantly explained this variation. This indicates that personality may either influence habitat choice, or that habitats favor certain personalities. Ultimately, personality types are segregated by habitat type, which suggests that such variation could lead to reproductive isolation.

► We tested for in situ intra-individual behavioral differences in giant sea anemones.
► We recorded a variety of microhabitat variables within 1 m of anemones.
► Anemones had consistently different withdrawal responses (i.e. they have personality).
► Personality differences were explained by anemone color and environmental factors.
► Differences may result from habitat variation or selective segregation.