Fire ant predation of turtle nests and implications for the strategy of delayed emergence
Kurt A. Buhlmann and Gina Coffman
University of Georgia, Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802 USA
Abstract: Red imported fire ants (Solenopsis invicta) consume eggs and hatchlings of turtles and other reptiles. We compared slider turtle (Trachemys scripta) hatching success and hatchling survival in nests in fire ant-free field enclosures to those in proximity to active fire ant colonies. Fire ant-induced mortality of turtle eggs incubating in the ground one, three, and six meters from active ant colonies was 60%, 50%, and 27%, respectively. Fire ants killed developing turtle eggs that had imperfections in the egg surface, but did not penetrate fully turgid eggs. Through the use of clear plexiglass tubes in which infrared cameras were inserted, fire ants were viewed underground as they encountered developing turtle eggs. Hatchling turtles were often killed soon after pipping from eggs. Some hatchling turtles successfully delayed emergence from nests in the fire ant-free area. However, hatchlings that delayed emergence in proximity to fire ant colonies were attacked or killed by fire ants. Introduced fire ants may be having an unseen and severe impact on turtle populations in the southeastern United States because several turtle species employ an evolutionary strategy of hatching in autumn, but delay emergence from the nest until the following spring.
Keywords: fire ants; turtles; eggs; delayed nest emergence; survival
SREL Reprint #2542
Buhlmann, K. A., and G. Coffman. 2001. Fire ant predation of turtle nests and implications for the strategy of delayed emergence. The Journal of the Elisha Mitchell Scientific Society 117:94-100.