Mechanisms for climate-induced mortality of fish populations in whole-lake experiments

Natl Acad Sciences
Publication Type:
Journal Article
Proceedings Of The National Academy Of Sciences Of The United States Of America, 2007, 104 (23), pp. 9715 - 9719
Issue Date:
Full metadata record
Files in This Item:
Filename Description Size
Thumbnail2006011473.pdf456.7 kB
Adobe PDF
The effects of climate change on plant and animal populations are widespread and documented for many species in many areas of the world. However, projections of climate impacts will require a better mechanistic understanding of ecological and behavioral responses to climate change and climate variation. For vertebrate animals, there is an absence of whole-system manipulative experiments that express natural variation in predator and prey behaviours. Here we investigate the effect of elevated water temperature on the physiology, behaviour, growth and survival of fish populations in a multiple whole-lake experiment by using 17 lake-years of data collected over 2 years with differing average temperatures. We found that elevated temperatures un excess of the optimum reduced the scope for growth through reduced maximum consumption and increased metabolosm in young rainbow trout, Oncorhynchus mykiss. Increased metabolism at high temperatures resulted in increased feeding activity (consumption) by individuals to compensate and maintain growth rates similar to thaty oberserved at cooler (optimum) temperatures. However, greater feeding activity rates resulted in greater vulnerability to predators that reduced survival to only half of the cooler year. Our work therefore, identifies temperature-dependent physiology and compensatory feeding behaviour as proximate mechanisms for substantial climate-induced mortality in fish pu=opulations at the scale of entire populations and wtaer bodies.
Please use this identifier to cite or link to this item: