Demography of an Urban Population of Alligator Snapping Turtles ( Macrochelys temminckii) in Texas

Understanding population demographics of Macrochelys temminckii (Alligator Snapping Turtle) requires long-term studies. Most previous studies do not provide demographic population data. We conducted a mark-recapture study of M. temminckii inhabiting Buffalo Bayou in Harris County, TX, from October 2016 through August 2021. We captured 110 unique individuals during 465 trap nights and recorded 45 recaptures. We generated 8 biological metrics. Capture per unit effort varied from 0.267 to 0.547 turtles per trap-night, the population estimate was 173 turtles (95% CI: 138-250), the sex ratio was 1.00 M:1.28 F, and density and biomass estimates were 4.43 turtles/river km and 89.9 kg/ km, respectively. Given that anthropogenic risks to this urban population may increase, continued monitoring and research is warranted.