The purpose of this research is to understand the mechanisms responsible for dramatic fluctuations in the number of salamanders in subalpine wetlands in central Colorado. Boom and bust cycles are often observed in animal populations, but such cycles are poorly understood in amphibians. A combination of approaches including long-term monitoring of salamander reproduction and survival in natural populations, field experiments that manipulate food (aquatic invertebrates) and other resources, and laboratory studies will be used to study mechanisms that could lead to population cycles. These data will be used to construct mathematical models to determine which mechanisms are capable of producing long-term the fluctuations in population size observed in this amphibian.
The decline of amphibians around the world is of great concern to ecologists, and it is important to be able to distinguish natural causes of change in amphibian populations from those related to human activities. Salamanders are the native top predators in subalpine wetlands and it is well documented that they play a key role in determining how many and which invertebrates coexist in the food web. This research is a first step towards understanding how cycles in the number of salamanders will affect the foodwebs and ultimately the functioning of these remote, pristine, ecosystems.
