Meeting Abstract

P2.108  Saturday, Jan. 5  Possible consequences of delayed nest emergence for hatchling snapping turtles (Chelydra serpentina): the timing of entry into aquatic environments influences body size, metabolic rate, and hematology. FINKLER, M.S.; Indiana Univ. Kokomo mfinkler@iuk.edu

Snapping turtle (Chelydra serpentina) hatchlings typically emerge from their nests soon after hatching and overwinter in aquatic habitats. Overwintering in nests is extremely rare, even in areas where freezing risks are low. I examined how the timing of entry into the aquatic environment influences body size, metabolic rate, and hematology. Body size and aerial O₂ consumption were measured weekly over a 28 day period in animals transferred from moistened sand into water (at equivalent temperatures) at 7, 14, or 21 days posthatching, and in animals held in moistened sand for the entire 28 day period. Animals maintained in sand experienced little change in live mass or carapace over the course of the experiment, whereas animals transferred to water gained mass (~5-7% within 24 h of transfer to water and ~9-12% at Day 28 compared to Day 7) and increased carapace length (~2-4% at Day 28 compared to Day 7). Aerial O₂ consumption rates decreased markedly within 24 hours of placement into water and remained low in aquatic animals compared to animals held in sand and measured at the same weekly intervals. Hematocrit and plasma osmolalities of animals held within water for at least one week were lower than those of Day 7 animals, whereas both measurements were higher in animals held in sand at Day 28 than at Day 7. The results suggest that hatchling snapping turtles that remain in terrestrial environments for prolonged periods experience changes in physiological condition (e.g., dehydration, stored energy substrate depletion, etc.) that could reduce survivorship during the first year of life.