Family: Sciuridae: (Fox Squirrel, Flying Squirrel, Chipmunk, Marmots, Prairie Dog, Tree Squirrel, Ground Squirrel)
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels, chipmunks, marmots (including woodchucks), flying squirrels, and prairie dogs amongst other rodents. Although native to Southern Ontario, squirrels in Toronto and other urban environments are frequently understood to be pests when they invade dilapidated structures, your attic, or the exterior walls of your home. Squirrels are also known to disrupt vegetable gardens and to take advantage of your neighbour’s birdseed feeder. On the reverse, as scatter-hoarders, 10-20% of seeds and nuts stored in squirrel caches remain uncovered, making squirrels responsible for quite a lot of tree propagation in the city. The two species of squirrel commonly encountered in Toronto are the Eastern Grey Squirrel and the Red Squirrel. Occasional flying squirrels can also be seen. Squirrels are adept surviving in the city, the omnivorous rodents even have biological controls that inhibit breeding in years of food scarcity, so although no one is tracking the number of squirrels in Toronto when populations in a particular area markedly increase, it typically indicates the presence of an artificial food source. To avoid nuisance numbers of squirrels in Toronto, the City’s Wildlife Department advises you not to feed them. Squirrels eat a broad range of foods including tree bark, tree buds, berries, wild mushrooms, nuts, corn, strawberries and tomatoes. When food is scarce, they’ve been noted to hunt insects, frogs, birds and their eggs, even other squirrels, occasionally gnawing on bones as a source of minerals that may be scarce in their diet. Although not known to be vectors of Rabies, squirrels in the City will chew through metal for food and can become a serious fire hazard, using electric cable as branches and gnawing on electrical insulation. If squirrels on your property become a nuisance, contact Addison Pest Control for an ethical, physical control system tailored to your property and particular pest population.
Eastern Grey Squirrel
Latin name: Sciurus carolinensis
Regarded as an invasive species in Europe, the Eastern Grey Squirrel, native to eastern North America, is our most ecologically essential forest regenerator. Frequently considered a pest in urban environments when they invade and nest (or drey) in attics, the exterior walls of the home or elsewhere on private properties, most of the squirrels that we see in Toronto parks and neighbourhoods are varying colours of this species. Often grey, with tan or rust areas and a white underside, some Eastern Greys are completely black due to adaptive melanism (black squirrels), and others completely white due to albinism (white squirrels). From head to tail, Eastern Grey Squirrels range from 16-24 inches and weigh 14-21 ounces. Like all squirrels, the Eastern Grey shows four toes on the front feet and five on the hind feet.
Eastern Grey Squirrels have been reported to live anywhere between two and twenty years in urban environments, but due to predation and challenges in their habitat, adults usually make it to around six. They are crepuscular rodents; this means that they are most active in the morning and early evening, and so avoid the daytime summer heat in Southern Ontario. Coupled with breeding times in the late Winter/early Spring and late Summer/early Fall, it is common sight to see Eastern Greys in mating and play, running circles around each other in City Parks. After an average gestation period of 40 days, an average of 2-5 squirrels are born to a very protective mother who is prone to rip out her fur to line her nest. Under optimal conditions, she may produce young during both of the year’s mating seasons. Squirrels are quite intelligent, and available food resources often dictate a female squirrel’s likelihood of producing kits in a given year. When food and security are available, squirrels will be more likely to reproduce. Young are weaned at ten weeks and may leave the drey at 12 weeks. Although only 1 in 4 is estimated to survive its first year, their chances of survival increase once the squirrel kits reach maturity and begin to reproduce, before decline rapidly in their sixth year.
Eastern Grey Squirrels do not hibernate, unlike a lot of city wildlife that enter into semi-hibernation, squirrels will simply remain in their dreys on colder days. Highly industrious, crepuscular, scatter-hoarders, each squirrel is estimated to establish several thousand caches each season. Astoundingly, only 10-20% of nuts hosted in squirrel caches are lost and eventually sprout. Squirrels have highly attuned spatial memories and will often return to caches several months after their making. Smell is also an invaluable sense used by squirrels to locate not only their caches but the hoardings of other squirrels as well. Competition also has lead Eastern Greys to develop deceptive tactics to feign or throw off potential thieves. If a squirrel suspects that it is being watched, it will often mime the gestures of digging or widening a hole and placing its food, while storing it back into its mouth to be cached later in a more secure location. Squirrels understand that they can be seen and that being seen can undermine the intentions of a particular task (storing food to hide later), so they will often hide in dense vegetation while establishing their caches. Eastern Greys also employ a repertoire of vocal and visual communication tactics, and varying combinations of the two depending on their environments, in dense canopies of forest they will communicate with each other predominantly through vocalizations, and in an urban context through physical gestures, tail flicks and facial expressions. Eastern Greys will warn each other of the presence of predators and will ‘coo’ to their young and potential mates. Similarly to raccoons, squirrels rotate their hind-feet 180 degrees to climb down trees and vertically vegetated surfaces headfirst, often at great speeds.
Predators include snakes, owls, raccoons, humans, hawks, weasels, foxes, domestic and feral cats, and dogs.
Mixed and Hardwood forests abundant with nuts are the natural habitats of squirrels, so logically, the common use of birdfeeders in urban centres provides an ample supply of food for Toronto’s as yet undocumented population of squirrels. Removing these artificial food supplies is perhaps the most effective strategy for controlling rampant squirrel populations when they spring up.
To control or prevent squirrels from inhabiting a structure on your property, physical control measures must be put into place in tandem with humane squirrel removal by Addison Pest Control. The property should be checked for holes in structures where they may be able to create a drey. If squirrels have already created a drey within a structure, they must be removed before permanent seals are installed, especially between the months of April and October when blind and vulnerable kits are being reared who may not be mobile. Overhanging tree limbs can be cut back from the property, ammonia and other deterrents can be spread around entryways to the den or talk radio can be loudly played, sources of food should be removed and open holes in the roof and chimney stuffed with easy to remove newsprint. Once all squirrels have confidently been evicted from the structure, entry points to the structure should be permanently sealed to prevent reoccupation. More tips and information, including municipal rules for wildlife trapping and removal, can be found on the City of Toronto’s website here. Addison Pest Control complies with all Municipal, Provincial and Federal regulations concerning the safe removal of wildlife pests.