Discussion
...According to our analysis, the effects of climate change on overwintering bald eagle bioenergetics in the Puget Sound region will be outweighed by the effects on bald eagle food supply. Warmer winters in the 2050s caused a slight decrease in eagle metabolism, but sharply accelerated decomposition of salmon carcasses, their main food source. We further expect reduced food quality; Stalmaster and Gessaman (1984) observed a steady temporal decline in energy content (kJ·g–1) of chum salmon carcasses, and the microbial and invertebrate activity that reduces energy content should increase at higher temperatures (DeVault et al. 2004). Although precipitation at our sites was projected to decrease slightly, winter flows in most Puget Sound rivers are expected to increase due to higher temperatures, land use changes, and reduced water storage in mountain snowpack (Elsner et al. 2010; Cuo et al. 2011). Higher flows may reduce carcass availability (Glock et al. 1980; Hunt et al. 1992) and visibility (Patterson et al. 2007), and have been correlated with reduced bald eagle foraging success in other systems (Brown et al. 1998). Moreover, bald eagle densities in Washington are expected to continue increasing (Stinson et al. 2007), which may lower individual feeding efficiency (Stalmaster and Gessaman 1984).
Currently, Chum Salmon is listed as endangered, it is time to return the Bald Eagle to the Threatened List.
From an Oxford Journal so there is general consensus about this mess.
ICES (International Council for the Exploration of the Seas - click here) Journal of Marine Science
Fukuwaka, M., Kaga, T., and Azumaya, T. Regional differences in climate factors controlling chum and pink salmon abundance. – ICES Journal of Marine Science, doi:10.1093/icesjms/fsr033.
Conclusions (click here)
Responses of chum and pink salmon stocks to global climate change vary among regions. Interdecadal climate changes might not be related to recent large increases in catches of chum and pink salmon. Because the thermal environment plays an important role in salmon population dynamics, a warming trend in the North Pacific might affect long-term changes in salmon abundance. In addition, global warming could affect not only the thermal environment, but also other freshwater and coastal environmental conditions for Pacific salmon (Bryant, 2009). The mechanisms controlling regional salmon abundance should be better understood to forecast successfully future conditions for Pacific salmon stocks, because responses of salmon stocks to global climate change vary among regions.
