Zoology 9th Edition by Stephen Miller

Exercise 1

Abiotic factors influence whether or not a habitat is suitable for an animal. Abiotic factors that are out of an animal's tolerance range make the habitat unsuitable. Energy is used by animals for existence, productive, and excretory functions. When food resources grow short, animals may enter torpor, hibernate, enter winter sleep, or aestivate.
Under drought conditions, resources become scarce. What component(s) of the energy budget of a whitetail deer would be the first to be compromised?