Tiny Mice Create Big Problems in Norfolk

They may be smaller and, some say, cuter, but in terms of pest control, mice are a more prevalent, more damaging and tougher problem than their two rodent cousins, Rattus rattus (black rats) and Rattus norvegicus (brown rats).

And as our British winter grows colder and wetter, mice are more likely to set up housekeeping in our cozy homes and businesses.

The mice we see most often in our pest control business are the house mouse Mus musculus. Two other types of mouse, the wood mouse and the harvest mouse, also may invade human dwellings but are most often found in sheds and homes in remote or rural areas.

The house mouse can be easily distinguished from wood and harvest mice by its larger size and a nearly hairless tail. In comparison, the other two species are much smaller and have tails that are covered with dark fur on top, lighter fur on bottom. House mice weigh about half an ounce and are 5 to 7 inches in length, including their 3- to 4-inch tails.

One reason mice present such a tough pest control problem is their small size. They need only a quarter-inch gap to gain entry into a building and require only minute amounts of food and water to survive. As a result mouse infestations are much more common and difficult to control than rat infestations – and every bit as hazardous to health and property.

Mice eat and contaminate human and pet foods, preferring grains but apparently willing to nibble on almost anything. One of our pest control customers discovered a
nest of mice
in a trunk where she stored historic family documents, vintage clothing and other mementoes. Not only did she find the remains of precious keepsakes shredded in a pile, she found dry dog food nuggets the mice apparently had confiscated from her pet's dish and tucked away for safe-keeping.

Mice transmit diseases such as salmonellosis (food poisoning) and can cause significant property damage, chewing through electrical wires, shredding insulation and gnawing woodwork.

Often people discover a mouse problem when they find tiny black droppings or notice the corner of a cracker box or bag of chips has been gnawed away. Mice also have a distinctive musky smell that may be noticeable. They are most active at night, can run straight up vertical walls and jump a foot off the ground. They reproduce rapidly, bearing as many as 10 litters of 5 or 6 pups per year; their life span is approximately one year.

The most effective ways to prevent mice are to keep all foodstuffs tightly sealed in glass or metal containers, to avoid leaving pet food out, keep all rubbish containers tightly sealed and to seal all gaps and crevices where mice can come in from outside, such as along pipes and wiring conduit. Self-installed metal barriers, such as tin can lids and steel wool, are effective barriers to gnawing but usually don't provide long-term protection.

Apartment buildings are especially notorious for mouse infestations, in part because mice are able to move easily from apartment to apartment along pipes and conduits and because it is difficult to ensure adherence to pest control measures by all tenants.

Once there is an established infestation in a home or business, it is almost always necessary to use mouse traps or poison bait to eliminate the mice. Baits are dangerous and must be kept inaccessible to children and pets. Electronic devices that emit a high-frequency sound, though widely advertised, are generally ineffective in preventing mice. A good feline or canine 'mouser' may help control the mouse population or discourage mice from moving in, but will generally not be able to completely eliminate mice once a site is infested.