Overview of Field Mice

Field mouse or field mice is a term that is used to encompass a number of different specific species of mice that are more commonplace throughout the United States, including in Southern California. The moniker of field mice is applied because of a frequent habitat of different and yet similar types of mice, which is fields. With that noted, field mice, broadly classified, can also be found living in forests as well as in residences, businesses, and other structures.

Physical Description of Field Mice

A typical adult field mouse is between 7 and 10 centimeters in length. The tail of a field mouse is about equal in length to that of the rodent’s body. An average adult field mouse weighs about 1.4 to 1.6 ounces.

Field mice fur commonly comes in a number of different colors:

  • Black
  • Brown
  • White

The Lifecycle of Field Mice

The gestation period of field mice is about 20 days. The average litter of field mice pups is between six to eight babies. The number of pups in a litter can run from three to 14 young. Female field mice will have five to 10 litters per year, depending upon their living situation. If field mice have access to suitable shelter and adequate food, they will have more litters per year. If field mice are living in the wild, they will forgo breeding and giving birth during the colder months of the year, even though these rodents do not hibernate.

Field mice are born hairless and blind. Infant field mice begin to grow fur at about six days from birth. Their eyes begin to open at about 12 days old. Field mice young are weaned at about the 20th day from their birth.

Female field mice in closer quarters will engage in what might fairly be called cooperative mothering. These females with children will cooperate in raising not only their own young but the pups born to other females. They provide for feeding, grooming, and protecting their own pups as well as those born to other females in their colony or living cluster.

Female field mice reach sexual maturity at about six weeks of age. Males reach sexual maturity at about the eight-week mark.

Socialization and Field Mice

Field mice live in two primary types of social structures, depending on their living environments. Field mice that have relatively decent access to food, water, and shelter will develop larger communities of colonies. This is the type of situation that occurs when field mice take up residence in a home. In such a situation, field mice develop a hierarchical structure.

Field mice in a larger outdoor setting will not develop a hierarchical social structure. Rather, groupings of smaller numbers of field mice will coexist to a degree, but in a less organized manner.

Field Mice and Residential Property

Field mice are adept at running, climbing, even swimming. As a result, they are quite capable of gaining entrance to a wide array of structures. Residential properties are particularly attractive or appealing to field mice because of the available shelter and food.

Field mice will nest in a number of different types of spaces in a residence. These include:

  • Attics
  • Cellars
  • Basements
  • Crawlspaces
  • Closets
  • Utility rooms
  • Under major appliances
  • Under hot water heaters or boilers

Signs of Field Mice in Your Home

There are telltale signs that field mice have entered and taken up residence in your home. Some of the more common signs of field mice infestation in a manmade structure include:

  • Droppings
  • Gnaw marks
  • Greasy trails (on floor and walls)
  • Scratching sounds
  • Scurrying noises
  • Squealing
  • Siting of the actual mouse

Bear in mind that field mice are considered generally nocturnal animals. Thus, odds are that you are more likely to hear noises associated with field mice in your home during the night. The same holds true for actually seeing a field mouse in your residence.

Hazards of Field Mice in Your Home

Field mice can create real hazards in your home. Because field mice chew and gnaw on objects, including the physical structure itself of a house in which they occupy, these rodents can do considerable damage to property. Depending on what these animals chew on, real hazards can be created in a home. For example, if field mice chew on the coating of electrical wires that run through a residence, which is something these rodents routinely do, a real fire hazard is created. Bare wires can spark, which can result in a residential fire. Indeed, about 25 percent of all house fires trace their origins to damage to electrical systems in a home caused by rodents.

In addition, another hazard associated with field mice infestation in a residential property setting is a disease. Field mice can carry harmful bacteria or viruses. Not only can field mice spread dangerous pathogens to people through direct contact, but they can also spread bacteria and viruses through their droppings, urine, and saliva. Thus, not only must contact with field mice be avoided, you must not make unprotected contact with droppings, dried urine, or dried saliva. Field mice droppings can contain live bacteria or viruses even when they dry out, in some cases.