In this project PI Henry Wilbur continues his studies of population dynamics and life history evolution in variable environments by monitoring 18 species of amphibians breeding in 32 natural ponds. All individuals of two species are followed in three ponds to explicitly measure vital rates, such as the probabilities of survival, reproduction, and movement between ponds. This study employs software developed for the project to recognize individuals from digital photographs taken as they move in and out of the pond, and new statistical techniques to estimate vital rates from these data. A second approach monitors breeding attempts and successful metamorphosis of all species in all ponds. The primary source of environmental variation is the local weather that is being linked explicitly to the hydrology of each pond.
Natural populations are influenced by many sources of variation from regional weather systems to random effects on individuals in small populations, such as opportunities to reproduce or exposure to mortality risks. It is important to understand the impact of this variation on population dynamics to make wise decisions about the management and conservation of natural populations, to decide how to protect species of conservation concern, to exploit populations for economic gain, or to control pests. This project also serves to train students in field biology and population modeling.
