Old Field Mouse: (Peromyscus polionotus)
The old field mouse (peromyscus polionotus) belongs to the cricetidae family. Old field mice average between 4 to 6 inches long, having a tail length of 1 to 2 inches and weigh between 0.28 ounces to 0.67 ounces.
Old field mice have short soft fur that is fawn colored. Its under – parts are gray or whitish in color. Their ears are long and large. Their tails are as long as their bodies and fur – less. They have 4 toes in on their front paws and 5 on their back paws and their claws are extremely sharp. Their eyes are big, round and black in color. They have 16 very sharp teeth. They are found throughout northern and central Florida. They prefer areas that have sandy soils and grass covered dunes near beaches, making these areas ideal for their burrows.
Old field mice are omnivores, consuming both plant and animals. Their primary diet consists of seasonal seeds, acorns, wild pea, blackberries, insects and other invertebrates and vertebrates.
Old field mice are mainly nocturnal. They also burrow and usually dig the burrow their self. These burrows are about 3 feet deep that have 1 or 2 tunnels, at the end of the burrow and above its nest they construct a branch tunnel may extend above the nest usually a few centimeters below the surface as an emergency exit. When a predator starts to enter or dig up the burrow the old field mouse “explodes” through this escape exit, fleeing from the predator. One old field mouse can have up to 20 burrows within its home range. Old field mice are very intelligent, researches have proven that old field mice will assess and think of a strategy before proceeding, if adequate time is given. They are extremely fast giving their size. Old field mice are hoarders, finding caches of seeds in their burrowed nests. Once the old field mouse establishes their territory, it usually becomes their permanent home range for life and may defend those small areas. Old field mice communicate by using their keen scenes of vision, hearing, scent and movements. In the wild old field mice average 18 months of life, due to their predators, some include snakes, owls, foxes and other animals. The old field mouse breeds throughout the year. One female can produce several litters a year. The average litter size is between 1 to 3, but they can have up to 4. Its gestation period is approximately 24 days. When the young are born their eyes closed, helpless and pink in color but are fur-less. Their eyes begin to open after 13 or 14 days. The young are weaned between the 20th to 25th day, at which they begin leaving the nest and venturing above ground.
The old field mouse is known to carry several diseases. They can also transmit some of these disease to humans and could be fatal. These diseases include leptospirosis, salmonellosis and tularemia.