RESILIENCY OF THE SOUTHWESTERN POND TURTLE (ACTINEMYS PALLIDA) AFTER DROUGHT IN SOUTHERN CALIFORNIA

Barry Nerhus; bnerhus@endemicenvironmental.net; Lyell Buttermore, Hannah Lee, Lyell S Buttermore

Southwestern pond turtle (Actinemys pallida) populations have been consistently declining throughout their range. This growing concern for population decline is exacerbated by increasing drought, urbanization, and fragmentation. Despite this, focused studies at the San Joaquin Marsh in Orange County, California have demonstrated continuous population growth and stability in the past ten years. We hypothesized that southwestern pond turtle populations at the San Joaquin Marsh demonstrate population stability and resilience despite two years of drought-like conditions. We analyzed the population demographics to determine impacts on population stability in the context of drought. We conducted a mark-recapture survey study over two years (2019-2020) at the San Joaquin Marsh that was then compared to previous pre-drought data (2008-2012). We found that the population estimate at this location had significantly increased in comparison to the previous status reports, even in the face of drought-like conditions. However, we also observed lower juvenile recruitment and a lower proportion of females in reference to males when compared to the previous study conducted prior to drought conditions. Our results indicate a need for conservation and water system management for southwestern pond turtles and further investigation into the status of pond turtle populations, especially after stochastic disturbance events.

Reptiles and Amphibians III  InPerson Presentation