SREL Reprint #2611

Effects of hatching time for larval Ambystomatid salamanders

Michelle D. Boone1, David E. Scott2, and Peter H. Niewiarowski3

1USGS Columbia Environmental Research Center, 4200 New Haven Road, Columbia, Missouri 65201
2Savannah River Ecology Laboratory, Drawer E, Aiken, South Carolina 29802
3Department of Biology, University of Akron, Akron, Ohio 44325-3908

Abstract: In aquatic communities, the phenology of breeding may influence species interactions. In the early-breeding marbled salamander, Ambystoma opacum, timing of pond filling may determine whether interactions among larvae are competitive or predatory. The objectives of our studies were to determine how time of egg hatching affected size, larval period, and survival to metamorphosis in A. opacum, and if early-hatching in A. opacum influenced the competitive and predator-prey relationships with smaller larvae of the mole salamander, Ambystoma talpoideum. Salamander larvae were reared from hatching through metamorphosis in large, outdoor enclosures located in a natural temporary pond in Aiken County, South Carolina, in two experitnents. In study 1, we reared early- and late-hatching A. opacum larvae separately from hatching through metamorphosis. In study 2, we examined how early- versus late-hatching A. opacum affected a syntopic species, A. talpoideum. In general, early-hatching A. opacum were larger and older at metamorphosis, had greater survival, and left the pond earlier than late-hatching larvae. Ambystoma talpoideum reared in the presence of early-hatching A. opacum had lower survival than in controls, suggesting that A. opacum may predate upon A. talpoideum when they gain a growth advantage over later-hatching larvae. Our studies demonstrate that time of pond filling and phenology of breeding may influence population dynamics and alter the nature of relationships that develop among species.

SREL Reprint #2611

Boone, M. D., D. E. Scott, and P. H. Niewiarowski. 2002. Effects of hatching time for larval Ambystomatid salamanders. Copeia 2:511-517.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).