Spotted Turtle and Blanding’s Turtle Research at PFW
The Spotted Turtle (Clemmys guttata) and Blanding’s Turtle (Emydoidea blandingii) are two species of turtles in Indiana whose populations are in decline. Both species inhabit various wetlands in the state and are historically distributed across the northern portion of Indiana (Ernst and Lovich, 2009; MacGowan, et al., 2005; Barlow, 1999; Harding, 1997). Both species are considered state-endangered in Indiana (Indiana State Wildlife Action Plan, 2015) and are on the International Union for the Conservation of Nature’s (IUCN) Red List of Threatened Species as endangered. Along with being state-endangered in Indiana, both species have also received Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) protection and were petitioned for being listed as federally threatened to the U.S. Fish and Wildlife Service (Racey, 2015; Adkins Giese, 2012).
Dr. Bruce Kingsbury and his students at Purdue University Fort Wayne (PFW) have studied the ecology and conservation of both species in Indiana. The research has helped gain an understanding of the ecological requirements of both species through habitat use and movement patterns in the populations of Pigeon River Fish and Wildlife Area (Barlow, 1999).
Current Research – Population Assessments
Currently and in partnership with the Department of Natural Resources and US Fish and Wildlife Services, Jessica Hinson, an IPFW graduate student, is conducting population assessments of Spotted Turtles and Blanding’s Turtles across their historical distribution in Indiana. She is also identifying functional population units throughout Indiana to provide more information in the development of conservation and management strategies.
Population assessments can involve multiple methods that depend strongly on the target species ecology and time constraint, but serve the ultimate purpose of providing pertinent information for conservation efforts. Jessica uses population surveys to conduct population assessments across the state of Indiana, based on the historical distribution of both species, habitat modeling, and records of sightings. Surveys will determine presence or absence of the species, as well as provide more details on habitat quality and sustainability in Indiana throughout their distribution. Any Spotted Turtles or Blanding’s Turtles that can be captured are also sampled for genetic analyses (in collaboration with Dr. Mark Jordan). Trapping is done at selected sites by Jessica to not only obtain more samples, but also validate her survey efforts.
Habitat modeling is done to identify and delineate functional population units (also known as management units or MUs), which are defined as separate populations in which individuals are clustered by their likelihood of ability to interbreed (Palsbøll, et al., 2007). Identification of MUs will be a combination of factors such as suitable habitat, species observations in the field, presence of barriers, presence of corridors, and genetic similarity.
References
Adkins Giese, C.L., Greenwald, D.N., Curry, T. “Petition to List 53 Amphibians and Reptiles in the United States as Threatened or Endangered Species under the Endangered Species Act.” Center for Biological Diversity. Center for Biological Diversity, 11 July 2012. Web.
Barlow, C. (1999) Habitat use and spatial ecology of Blanding’s turtles (Emydoidea blandingii) and Spotted Turtles (Clemmys guttata) in Northeast Indiana. M.S. Thesis, Purdue University, Fort Wayne, IN.
Ernst, C. H., and Lovich, J.E. Turtles of the United States and Canada. JHU Press, 2009.
Harding, J.H. Amphibians and Reptiles of the Great Lakes Region. University of Michigan, 1997. Print.
Indiana State Wildlife Action Plan. (2015) Indiana Department of Natural Resources, 1-315.
MacGowan, B., Kingsbury, B., Williams, R. Turtles of Indiana. West Lafayette, IN: Purdue University, 2005. Print.
Palsbøll, P.J., Berube, M., Allendorf, F.W. (2007) Identification of management units using population genetic data. Trends in Ecology and Evolution 22: 11-16.
Racey, M. “Federal Wildlife Officials Respond to Petitions to List Dozens of Species under the Endangered Species Act.” U.S. Fish and Wildlife Service. U.S. Fish and Wildlife Service, 30 June 2015. Web.