Immigration and Dispersal of Slider Turtles Pseudemys scripta in Mississippi Farm Ponds

Emigration and immigration rates in a farm pond population of the slider turtle Pseudemys scripta were studied for 8 consecutive years. The pond nearest the primary study pond was sampled in 4 years and two more distant ponds 1 year each. Annual emigration increased from 18% to 61 % of the population during the study, seemingly as a result of algicide applications eliminating the population's potential food. Males emigrated more frequently and farther than females. Over 40% of older adult males spent only 1 year in the primary study pond. Younger males first encountered at 1-3 years old were more sedentary, with fewer single-year records (8 %) and higher proportions staying in the primary pond over several years. Between 18-41 adult males (24-47% of captures) and 3-15 adult females (10-41 % of captures) were immigrants each year. Females were more sedentary than older adult males as measured by single-year records, annual recapture rates, and higher proportion staying over several years. Immigrants of both sexes emigrated more frequently than residents. In general, the results support predictions of movement patterns by sexually dimorphic aquatic turtles (female larger than male), with higher vagility among males. A lack of increased vagility in young males reaching maturity, however, runs counter to previous findings.