20.4 Wednesday, Jan. 4 Thermal ecology of yellow mud turtles (Kinosternon flavescens) during hibernation SANDERS, T; KAZMAIER, R; LIGON, D*; Missouri State University; West Texas A&M University; Missouri State University DayLigon@MissouriState.edu
Yellow mud turtles (Kinosternon flavescens) are putatively aquatic, yet presence of surface water is seasonal and often unreliable across much of its range. Summertime estivation is frequently necessary to survive periods of drought. Additionally, low winter temperatures necessitate hibernation in the northern parts of the species’ range. As a result, individuals frequently spend large portions of the year in terrestrial dormancy. We measured daily and seasonal fluctuations in soil temperatures and body temperatures of hibernating yellow mud turtles at Gene Howe Wildlife Management Area in the Texas panhandle from September 2009 to March 2010. We then used these data to determine: 1) when individual turtles left their pond, burrowed into the soil and began winter dormancy; 2) the depth at which turtles hibernated; 3) the timing and frequency with which they changed depth; and 4) the date on which each turtle emerged from hibernation and returned to the pond. Additionally, temperature-specific metabolic rate data obtained from captive turtles were used to estimate energy consumption during hibernation. Among seven turtles from which data were recovered, hibernation began 20 September–4 October, turtles buried themselves 11–80 cm below the surface, and several turtles burrowed progressively deeper as winter progressed. Spring emergence was asynchronous, occurring 5 March–21 April. Lipids were likely the dominant metabolic substrate fueling hibernation, and turtles used an estimated 38–51 kJ during hibernation.