Webinar: How will increased temperatures affect bird communities?
Channel: Conservation and Adaptation Resources Toolbox
Date: 27/11/2013

Webinar: How will increased temperatures affect bird communities? - a view from physolocial ecology
Speaker: Dr. Blair Wolf, The University of New Mexico
Date: November 20, 2013

About the Speaker
Presenter Blair Wolf is a professor of biology at the University of New Mexico in Albuquerque NM and studies the behavior, ecology and physiology of desert animals.

Summary
The capacity for evaporative heat dissipation has been largely overlooked in consideration of future species' distributions, but varies greatly across terrestrial vertebrate taxa and will have a critical influence on species persistence in many environments. 

Anthropogenic effects on climate are increasingly likely to produce 4-6°C of warming by 2100, with an increase in the frequency and intensity of heat waves.  Many terrestrial animals occupying habitats ranging from arid to humid will routinely be exposed to levels of heat stress exceeding those currently experienced.  Which taxa are prepared to cope with these new challenges?  How will hotter environments affect performance and life histories? 

We examine fundamental differences in thermoregulatory and energetic strategies among terrestrial vertebrates and explore how this variation may differentially constrain species' performance in hotter environments. We show how metabolic performance and evaporative capacity interact to predict heat tolerance and we hypothesize how the efficiency of evaporative mechanisms may facilitate survival in the heat. While many birds and several mammal groups (canids, felids, many ungulates) have the capacity to dissipate both metabolic and environmental heat loads evaporatively, most mammals (rodents, insectivores, megabats), in contrast, have limited evaporative capacities that are insufficient to cope with significant heat and so resort to behavioral means in an attempt to mitigate heat stress. 

Evaporative capacities may not only determine short-term survival, but also the capacity for work. Heat waves, for example, will produce conditions where compensable limits of tolerance in heat or water balance are exceeded and rapid death occurs. More chronic effects of greater heat stress include a decline in body condition due to constraints on foraging, which may limit water and energy intake, and carryover to produce reproductive failure during periods of hotter weather.