Nest predation can be the largest source of mortality for many bird populations, and nest predation is great enough in many landscapes to limit population or cause population declines. In an earlier study we showed nest predation and productivity was affected by an interaction between landscape level fragmentation and temperature; higher temperatures had the greatest negative effect on productivity in the least fragmented landscapes. In this study we investigated the potential mechanisms for temperature effects on avian productivity and found support for our hypotheses that nest predation by snakes increases with temperature. We also found a positive relationship between temperature and nest predation by birds. These results demonstrate warming climate may affect species through complex community level interactions, and productivity of some birds could be most affected by climate warming in the landscapes where they currently have the greatest productivity.
Wednesday, December 4, 2013