What to do when mice head indoors
Published: Saturday, September 28, 2013 at 6:01 a.m.
Last Modified: Thursday, September 26, 2013 at 9:54 a.m.
You probably have noticed the days are getting shorter, and by 8 p.m. it is already dark.
With the shorter days come cooler evenings, and this is not lost on animals, among them, the local field mouse population. As the cooler temperatures arrive, mice begin seeking housing options that provide warmer shelter. Often, with the advent of cooler weather, mice invade homes, sheds and other structures that will provide shelter from the cold.
Their gnawing damages goods and property, their feeding activities ruin shelved food, and their urine stains stored goods.
Mice prefer to feed on grains, but usually nibble at a wide variety of foods including bird seed and pet food. Field mice require only 1/10-ounce of food and 1/20-ounce of water daily, surviving on food, alone, if it has high moisture. Field mice are brown to gray, with the tail as long as the body. Adults weigh about ½-ounce; their droppings are 1/8-inch long and rod-shaped. Their life span is typically one year, and they reach sexual maturity in only six weeks, after which they have up to eight litters per year, with five to six young per litter. One doesn't need to be an Isaac Newton or a Carl Gauss to realize two mice soon become many. Mice are largely nocturnal, but will be active during daytime hours when food is scarce, when there is overpopulation or when a poison has been used and the population is sick. Mice are good climbers and are inquisitive, actively exploring anything new. They range only small distances from their nest, generally within 10 to 30 feet.
Since mice are active at night, it is necessary to recognize signs of their activity. Often, the first sign noticed are droppings or urine stains in and around buildings. Rodents usually have favorite toilet areas, but will void almost anywhere. Old droppings are gray, dusty and will crumble. Fresh droppings are black, shiny and puttylike. Rodents gnaw almost every day in order to keep their teeth short and sharp. Teeth marks on food, building materials, wire and edges of beams are indications of rodent presence. Often mice can be heard in the quiet hours of the night as they scurry from hiding to search for food.
Given the rate at which they reproduce, mouse prevention is a prudent use of time for homeowners. Good housekeeping or sanitation is fundamental in rodent control. Eliminating food, water and harborage for rats and mice can rapidly reduce rodent populations. Clean up garbage and rubbish, properly store garbage (use metal garbage cans with tight-fitting lids), store food in covered, mouse-proof containers, and dry up any sources of water. If you have any fruit trees or a garden, pick up fruits and vegetables when ripe so rodents will not feed on them. Sanitation must be used constantly to be effective. Yearly clean-up programs are not frequent enough to insure the measures needed to prevent infestations.
If you discover mice in your garage, shed or barn, quickly take action. Although underrated, trapping is still an effective means to eliminate rodent problems. Traps are inexpensive, and are a good choice for mice control. Baited traps rely on the rodent being attracted for feeding. The bait must compete with other available foods, so it is important that food used for baiting be kept fresh. Peanut butter, bacon squares and gumdrops are good bait for mice, as well as small wads of cotton (they look for nest materials). Set baited traps at right angles to walls, behind furniture and near harborage where mice run. Remember to set traps where children and pets will not be hurt.
Poison is another option, but it has several drawbacks that make it undesirable for home use. If mice consume the poison, then later die under cover, they often are not detected until odor becomes a problem. Poison baits also may be attractive to non-targeted groups, and can be a hazard for pets. Poison baits require precautions and management that is an unnecessary risk for control, given the option of trapping.
With the arrival of fall, and the associated cooler temperatures, it is a good time to be aware that mice are seeking shelter. If you have a rodent sighting or note signs of their presence, act quickly to prevent problems from multiplying.
David Holmes is Marion County extension director. Contact him at firstname.lastname@example.org.
Reader comments posted to this article may be published in our print edition. All rights reserved. This copyrighted material may not be re-published without permission. Links are encouraged.