| Individual animals move among habitats for a variety of reasons. These movements can profoundly affect the fitness of the individual and the dynamics of populations. There is, therefore, a long history of ecological research on this subject. However, much of this work has been conducted in isolation within the boundaries of several sub-disciplines with little resulting synthesis. My research on the eastern painted turtle, Chrysemys picta picta, synthesizes three aspects of its movement ecology, from behavioral responses to population consequences. I first ask the question how does C. picta search for aquatic habitat on land? Second, I determine rates of movement between seemingly isolated ponds and ask whether these movements differ by age and sex? Finally, I ask if individual movements scale up to affect population dynamics at the pond level?; Chrysemys picta was found to have a linear search strategy over both small and large spatial scales. The search path became more sinuous under complete cloud cover. This linear search strategy presumably improves the ability of C. picta to find ponds in the landscape. In a mark-recapture study spanning four years, 245 of 527 recaptured turtles (46%) moved between ponds. The proportion of individuals in each age-sex class that moved between ponds did not differ. However, destination of emigrating turtles did vary by age. Immature turtles typically moved to the closest pond. In contrast, adult C. picta, particularly adult females, exhibited greater variation in their movement behavior. Adults avoided low quality habitat while immature turtles did not. The drying of ponds strongly influenced movement rates and such rates were not density dependent. Interpond movements significantly affected pond-level population dynamics. Immigration contributed greatly to population growth rates for adult and subadult female C. picta. The effect of immigration was most profound in a seasonal, less isolated pond. In the permanent ponds, local factors (i.e., survival and in situ recruitment) were more of an influence. My dissertation integrates behavioral aspects of movement with population responses. I believe that such a synthesis is needed to advance both the science of ecology and its application to conservation. |
