Winter biology

[mindstalk]

I'm reading Winter World by Bernd Heinrich, an author I know from Ravens in Winter and Mind of the Raven. Some facts:

* Hibernation is pretty much about getting past food shortages, not cold per se. Animals with enough food stored up or otherwise available are happy to frolic all winter.

* Hibernating mammals rouse themselves multiple times to enter REM sleep. This can cost them half their winter energy expenditure. Apparently having a body temperature of 3 C doesn't exempt you from sleep deprivation and it's important to do something about that.

* Word of the week: sub-nivian, or beneath the snow. As in chipmunks live in a hidden sub-nivian world of snow tunnels and food caches. Wikipedia spells it "subnivean climate".

Comments

[heron61]

Hibernating mammals rouse themselves multiple times to enter REM sleep. This can cost them half their winter energy expenditure. Apparently having a body temperature of 3 C doesn't exempt you from sleep deprivation and it's important to do something about that.

This also applies to the small mammals that enter far deeper states of hibernation than bears, and that (at least from the little I've read) seem to come close to freezing? Wow, I had no idea. Roughly how often to they cease hibernating and sleep?

[mindstalk]

He says arctic ground squirrels warm up from sub-freezing to 37 C about a dozen times a winter.