Rodents of the Midwest: identification and control
In the Evansville area we commonly deal with house mouse. The house mouse is a grey to red ,small rodent which as the name implies lives in very close proximity to humans. The house mouse is also very adaptable in an urban setting. Often homeowners will find the house mouse in the walls of the home infesting areas around insulation and electrical wire conduit. We find that it is a very common rodent species in our Paducah, Owensboro and Evansville markets. These mice can contaminate food stores, unsealed food and general areas where they urinate. Being very small they only need to width of a dime to enter homes. Areas that are not properly sealed around vents, windows and doors are common entry points and need to be sealed up properly before fall begins as these rodents will start to enter indoors as the weather cools. Other likely areas for entry would be pipe accesses from plumbing, gas or air conditioning pipes penetrating the foundations. Steel wool is your best defense from allowing entry at these areas as rodents can’t easily chew through this material.
Another common rodent found in the tri state area is the deer mouse. Deer mice are distinguished by the color features among other traits. House mice typically have uniformly grey color, while deer mice have white bellies and white feet with darker upper bodies. Deer mice also have larger ears and eyes. Deer mice typically live in rural or wooden areas but also migrate indoors as the weather cools in the fall. Deer mice have the same access characteristics as the house mouse. Sealing properly is critical to control their infestations. This species is known to commonly jump over glue boards in order to escape capture. Often the only mice caught in glue boards or multi catch traps are juveniles of the species. The deer mouse is a common carrier of hantavirus and contaminates food stores in the same manner as the house mouse.
The Norway rat is one of the most difficult rodents to control in the Evansville area. This rat is a very large rodent with large bodies with short noses and ears. A comparison in size would the grey squirrel. As a matter of fact, many people in the Midwest describe a grey squirrel as a rat in a cuter outfit. Rats can be very damaging. Being right at home in the inner city, farmland, sewers and businesses adapt to their surroundings and become very suspicious of new items in their territory sometimes avoiding bait boxes and glue boards with even the slightest of human scent. The Norway Rat is known for its borrowing activity. Highly infested areas will typically have rodent runs underground on the exterior of the structure as well as crawlspaces under a structure. They can do major damage to the interior of walls and create fire hazard by their constant gnawing on items such as electrical wiring. A very tough animal to control and even tougher to trap, a professional such as Pass Pest Control is typically necessary to keep them under control.
The Roof Rat is a very controversial pest in the Midwest as it is typically associated with infestations in the southern United States. However, Pass Pest has confirmed their existence in the Paducah and Evansville area. Roof rats typically have longer tails and longer ears than the Norway rat. They are commonly seen in areas jumping from building to building or running along electrical lines. Both infestations found in the tri state area were found in areas along railroad tracks near grain storage areas. As the climate warms we may encounter these even more but as of today I would classify them as an occasional invader while being transported via train or truck.
Voles are also very common in the Evansville area. Currently we experience three types of voles, the woodland, prairie and meadow. All voles leave unorganized path in the grass where they are foraging with paths 1 to 2 inches wide. They commonly burrow into the ground in search for food and shelter but their burrows are typically very shallow. Their entry holes into the ground are usually around the size of a quarter or slightly larger. While typically not that common indoors most of their damage is to plants and trees as they feed on roots and bases of both plants and trees.
The key to identifying and controlling most structure infesting rodents is to look for “rub” marks. Rodents fur is very oily. As they frequent the same areas and can be habitual dark stains on walls are a very good indicator of a rodent problem.
