Meeting Abstract

127.5  Tuesday, Jan. 7 14:30  Female Personality Depends on Body Size, Reproductive State, and Social Context in the Invasive Western Mosquitofish HEMINGWAY, CT*; SARGENT, RC; St. Edward’s University; University of Kentucky cheming@stedwards.edu

The western mosquitofish (Gambusia affinis) is one of the top 100 invasive species worldwide. Native to North America, this fish has been expanding its range naturally up the Mississippi River drainage. They are native to western Kentucky, and over the last 50 years have expanded their range eastward throughout the entire Commonwealth. We study the ecological and social determinants of microhabitat choice, dispersal and range expansion in this species. Predation, body size, sexual conflict, and personality of the focal fish and its shoal mates are all known to affect microhabitat choice and dispersal in this species. We focused on the interaction between personality and body size. Personality in animal behavior is a multivariate behavioral phenotype that consists of repeatable individual behaviors (e.g. shoaling, predator inspection), and is thought to be fixed over an individual’s lifetime. We found, however, that female personality is plastic rather than fixed. Larger females are less likely to shoal and more likely to inspect predators than smaller females. Females about to give birth are also less likely to shoal and more likely to inspect predators than are females earlier in their reproductive cycle. These results suggest that female personality changes as she grows, and with stage of her reproductive cycle. We also examined these fish in social groups. Both predation and sexual conflict disrupt female social networks and result in smaller shoals. Predator inspection in solitary trials positively correlates with predator inspection and negatively correlates with shoal size in social groups.