Shifts in amphibian population dynamics in response to a change in the predator community

Predation can affect prey behavior, demography, abundance, and distribution, particularly in lentic freshwater ecosystems. Fish are predators known to reduce the abundance of their restrict distribution species. Using time series which spanned 43 22 yr, respectively, we analyzed effect a change fish predator community on dynamics two pond-breeding amphibian populations (Rana temporaria Rana dalmatina). Specifically, used state-space model allows for density dependence observation error, ask whether predation risk affects population growth rate return point around fluctuate. The results showed that type error assumed did not biological parameters. We found evidence both populations. was strong where invaded previously fish-free pond. weaker from cyprinid pike. have effects dynamics. observed dynamical pattern is phenomenologically similar alternative stable states.