Alternate name: Beach Mouse

Family: Muridae, Mice and Rats view all from this family

Description Whitish to fawn above; white below. Tail short, bicolored. L 4 3/4 -6" (122-153 mm); T 1 5/8 -2 3/8" (40-60 mm); HF 5/8 - 3/4" (15-19 mm); Wt 1/4 - 1/2 oz (8-15 g).

Endangered Status Six subspecies of the Oldfield Mouse are on the U.S. Endangered Species List. The Choctawhatchee Beach Mouse, the St. Andrew Beach Mouse, and the Anastasia Island Beach Mouse are classified as endangered in Florida; the Alabama Beach Mouse is classified as endangered in Alabama; and the Perdido Key Beach Mouse is classified as endangered in Florida and Alabama. The Southeastern Beach Mouse is classified as threatened in Florida. The major factors contributing to the decline of these mice are residential development of their coastal habitat, tropical storms, competition with introduced House Mice, and predation by cats and other carnivores.

Similar Species White-footed, Cotton, and Florida mice are larger and darker, with longer tails.

Breeding Reproduces year-round in South Carolina, producing several litters of 3 or 4 young each; gestation 23-24 days.

Habitat Old fields; beaches.

Range Southeastern U.S. from Alabama, Georgia, and sw South Carolina south through n and e coastal Florida.

Discussion A burrowing species, the Oldfield Mouse constructs, at the far end of its burrow and above the nest, a branch tunnel extending upward and ending just below the ground's surface. If a predator starts digging into the burrow, the mouse will often "explode" through this escape hatch, thereby eluding the startled predator. Burrows are open at times, closed at others, especially if heavy rains are imminent. Seeds and insects form the bulk of this animal's diet, although it also eats blackberries and wild peas. Several subspecies of the Oldfield Mouse have been described that are geographically separated from one another and are evolving in different directions.