Have you ever noticed the big difference of how winter wind feels on your skin vs. the summer wind? A difference so noticeable that when we seek shelter from this wind we immediately feel warmer. Now imagine that you lived in a nest built in the fork of a tree made of only leaves and twigs. This nest would be leaky when it rained and would not be the most efficient at keeping the wind out. Add in tree swaying from the vicious wind and the insecure shelter from predators who prey on your vulnerability. I just described what small rodents deals with during the winter. This is why many of them seek refuge in the attics, crawlspaces and walls of our homes. Basically, for the same reasons we don’t sleep in their nests outside! Even though an attic is much cooler than the inside the living space of a home, it is still 10-20 degrees warmer than the outside because of the insulation. Not to mention, an attic, crawlspace, or house is a safe place from most predators such as cats, hawks or owls. Why would they want to leave? Soon after entering most will have stored food or even dropped a litter of young inside. Animals don’t think the way we do. They do things strictly for survival not for entertainment. That’s why I’ve highlighted the top 4 rodents species that inhabit homes most frequently during the winter.

Grey squirrels and flying squirrels are notorious for entering homes and living in attics. They can have 2-3 litters a year and are known for gnawing on wires and matting down insulation. Grey squirrels do not store food inside of homes for the most part. They store food outside by burying it in different places, thus we call them scatter hoarders. They are very territorial and will run off other squirrels from their nesting area. Flying squirrels are not territorial and are rather social. They store food in large quantities in specific places, therefore we call them cache hoarders. Most homeowners can expect to hear noises from grey squirrels anytime from sun up to sun down. They are considered to be diurnal or day time animals. Flying squirrels are most active at night because they are truly nocturnal. Most people complain about hearing the noises before and after midnight. These two rodents are number 1 and 2 on my list and account for the majority of the nuisance animal calls we receive during the winter.

Although historically, rats and mice are the top 2 nuisance animals in the world, they are number 3 and 4 on our list this winter. One interesting fact of rats and mice inhabiting human structures is that chances are these rodents were living in the attic well before the winter hit. These two species of rodent are considered the most commensal in our country. Rats and mice are much more content to live around humans than in the wild.

They are also notorious for gnawing on wires and are extremely well known for leaving a tremendous amount of droppings in and around our homes. Rats have a poorly developed bladder and they generally leave a drop of urine with every couple of steps they take. This is how they find each other as well as find their way around in the dark. They have poor sight, but have an acute sense of hearing, smell and touch via whiskers. Rats and mice often store food inside and while venturing into homes, they may sometimes take food items they run across. This happens especially when pets are present in the home. Both species of rodents are very clever in finding unnoticeable ways into our homes. Mice are very curious by nature and will often explore their surroundings much more than rats, which are shy by nature and have neo-phobia (a fear of new objects). Both are carriers of endo- and ecto-parasites and they can have offspring every 19-28 days.

So, remember that most urban wildlife are very opportunistic and that many are waiting to occupy vacant voids of any attic, crawlspace, or living space near you. The best way to solve an recurring animal problem is to not only remove the nuisance animals but to also keep them out of the structure with hardy barriers. Here at A.C.E. we handle all aspects of trapping and the application of these exclusion barriers to keep your home nuisance wildlife free .

Nick Jackson
ACE Operations Mgr