Animal dormancy: squirrels

I do like it when the leaves fall, and our skies open up. We've had rain, snow, sleet and hail, sometimes within the same hour. Once the leaves fell, I noticed this squirrel nest in the tree. Turns out it is a black squirrel. We have several. It sat in the sunshine for about 10 minutes, then ducked back into the nest.


We have lots of rodents! I was reminded that they come and go in winter. Many of our critters become dormant, if they don't migrate.

Animal dormancy: New World Encyclopedia

• 1.1 Hibernation – heart rates can slow by as much as 95% (e.g., bears, raccoons).
• 1.2 Estivation – like torpor, slumber, slow down of metabolism in summer (e.g., salamanders, squirrels).
• 1.3 Diapause – deer (pregnancy), insects in winter remain as embryos.
• 1.4 Brumation –cold-blooded animals (e.g., snakes).
• 1.5 Torpor – diurnal metabolism slows by half.

The question is which ones hibernate?

Properly speaking, however, use of the term [hibernate] should be confined solely to warm-blooded homoiotherms—i.e., birds and mammals whose feathers or fur serve as insulation to reduce heat radiating from the body and aid in the maintenance of constant body temperatures, which normally are independent of those of the environment. 

I found an interesting reading comprehension passage, with questions, that explains hibernate and estivate, as the critters manage in our harsh climate in Canada. Our critters have choices: hibernate (sleep in winter), estivate (sleep in the heat), migrate. I think we need another word, as the tree rats are waking from hibernation on an irregular basis.

hibernate, estivate,

I'm finding that the critters are doing less hibernation, as our temperatures went from warmish to cold, to snow, and back to rain this November: precipitation. It's mostly melted. The critters have come and gone. It cannot be good for them. The deer need the cold temperatures to go into heat, and for the males to get any action. The females are only in heat for 24 hours.

Yet, the red squirrels, the black and gray squirrels, have been quite active. I haven't seen the chipmunks for a month, or so.

The red squirrels have been estivating

They are so pretty. Wicked tempers, and bullies, even with larger squirrels! But that lovely red fur!
They are busy little beavers. Red squirrels estivate, they do not hibernate. They go into a torpor over the winter, a dormant state, arising to eat, from time-to-time. You can tell how hungry they are by whether they eat found food on the spot, or take it home to store it.
The video (below) shows how frantic they are: up, down, across, over. The cats love chasing them, but they're too quick for my feline buddies.