Population Estimates, Demography, and Habitat Assessment of the Pearl River map turtle (Graptemys pearlensis) in the Pearl River Drainage of Mississippi

The Pearl River map turtle (Graptemys pearlensis) is a highly riverine Emydid endemic to the Pearl River drainage of central and southern Mississippi and southern Louisiana. First described in 2010, G. pearlensis was listed as federally Threatened in 2024. . Due to its relative novelty as a species, no rigorous site-specific population estimates of G. pearlensis in Mississippi have been conducted. The primary goal of this study was to implement a replicable method of assessing the population of G. pearlensis throughout the Pearl River drainage system of Mississippi. A secondary goal was to describe habitat associated with G. pearlensis abundance. We captured a total of 186 G. pearlensis across 53.2 rkm. Our drainage wide population estimate for G. pearlensis was 22.4 turtles per rkm, although site abundance varied from 2.2 to 141.7 turtles per rkm. These numbers are significantly lower than G. oculifera, which was estimated at 96 turtles/rkm, with site abundance between 47 and 217.7 turtles/rkm. This leads us to recommend continued monitoring of G. pearlensis, and to support their protected status. We also performed habitat analysis across the main stem Pearl River and on 12 tributaries and creeks. As the only apparent significant habitat variable associated with G. pearlensis density was sandbar area, we recommend future studies focus on more thoroughly assessing habitat at locations with both low and high densities of G. pearlensis.