Ecology of Chicken Turtles (Deirochelys reticularia) in a Seasonal Wetland Ecosystem: Exploiting Resource and Refuge Environments
KURT A. BUHLMANN1,2, JUSTIN D. CONGDON1, J.WHITFIELD GIBBONS1, and JUDITH L. GREENE1
1University
of Georgia, Savannah River Ecology Laboratory, Drawer E, Aiken, SC,
29802 USA
2University of Georgia, Odum School of Ecology, Athens, GA,
30602 USA
Abstract:
Chicken
turtles (Deirochelys reticularia) were studied at Dry Bay, a Carolina
bay wetland in South Carolina, USA, between 1994 and 2005. A total of
461 individual turtles was marked from 1993–1998. Minimum ages at
maturity for males and females were 2 and 5 yr, respectively. All females
reproduced each year, and 60% of reproductive females produced two clutches
per season. Clutch size averaged 9.8 eggs, and both clutch and egg size
increased with body size. Hatchlings averaged 29.2 mm PL, and body sizes
were similar among years. Yearling survivorship varied from 7.0–43.0%
(mean=20.4%) among years. The highest survivorship of a hatchling cohort
to age 5 was 0.21. Survivorships of juveniles and adults while in terrestrial
refugia were higher than survivorships while in aquatic habitats. No adult
females survived a 2-yr drought (2001–2003), and the bay was repopulated
by mature males and juvenile females (most from the 1998 hatchling cohort)
that had survived the extended drought in terrestrial refugia. Three of
those juvenile females matured and produced eggs in 2004. The traits of
early maturity, high susceptibility to predation, and shortened longevity
characteristic of chicken turtles are consistent with predictions for
species that live in seasonally fluctuating and highly unpredictable aquatic
habitats.
Keywords: Chelonia; Chicken turtle; Deirochelys reticularia;
Life history; Reproduction; Seasonal
wetlands; Survivorship
SREL Reprint #3106
Buhlmann,
K. A., J. D. Congdon, J. W. Gibbons, and J. L. Greene. 2009. Ecology of
Chicken Turtles (Deirochelys reticularia) in a Seasonal Wetland
Ecosystem: Exploiting Resource and Refuge Environments. Herpetologica
65(1): 39-53.
