Question book 4 : What do the mating habits of a Grey Squirrel look like?

For some reason I feel compelled to give all my of my question book entries titles like sequels of a long rehashed story. They really have no bearing on what is contained within the blog entry.. though maybe one day I’ll get creative and find a way to make the titles more descriptive.

While I was out tracking on December 25th, I saw signs of a Coyote in preestrous. This is the preliminary phase of the estrous cycle where she is depositing scent, and courting with a potential mate. I thought this was cool because I didn't know that this preestrous cycle can last for so long (a couple of months).

Also when I was out I came across some Grey Squirrel (Sciurus carolinensis) tracks with blood beside them. Now this wasn't in with a urine deposit, but instead little droplets fallen within the width of the trail but never within the tracks themselves. I first thought this might be the same sort of preestrous cycle for the Squirrel, but now, after thinking about it for a couple of days I think it may be something else.

But, all this to say, it got me wondering about the reproductive cycles of one of the most common conspicuous mammal species in my area. When do Grey Squirrels mate? How many partners do they have? Do they mate in the trees, on the ground? How many little Squirrelings do they have? Are they pups, kits, kittens?

So I figured I would look some of this up and try and write it out.

Grey Squirrels are capable of breeding within their first year in their more Southern range, and then as yearlings (within their second year) in the more Northern ranges. I figure where I am located, in Southern Ontario, I am in the Northern range.

Breeding is initiated by lengthening day light, usually in February. Males testes are usually up in the abdominal cavity throughout most of the year, but then they descend as the mating season gets closer. An individual female is in oestrous for only about 8 hours and in that time males must find the females and then try to mate with her, but I still can't find out how long the courting, or preestrous phase lasts before hand.

Males often chase each other while pursuing the female in heat, chattering at other males and alarming making the other males believe that predators may be near so they freeze and hide. Some males will hang out in the females territories, sitting out all the chasing, but instead wait for a chance when no other males are close and then approach the female. Eventually the female takes off, and the males follow. She then allows the males of her choice the chance to mate with her. This is sometimes the male who has been consistently able to fend of the rest of the males, or sometimes it is just a lucky male in the right place at the right time. Copulation can take from 1 minutes to 25 minutes. The ejaculate of the male can coagulate for form a sort of vaginal plug which reduces the success rate other other males sperm fertilizing the females eggs. Sometimes, while grooming themselves after copulation, the females can find and remove this plug.

I have ready different sources that say different things about whether the females will then go on to find other males to mate with, or if they will just be happy with the one partner. I would love to figure out which is a more common practice.

After mating, there is a gestating period of 38-45 days. Once the altricial litter of 1-4 baby Squirrels (“kits” or “kittens”) are born females take on all the roles in rearing the young with no assistance from the males.