Just as their name suggests, beach mice live on the beach. They look like house mice yet are often whiter and slightly smaller. They make their homes in sand dunes from Alabama to Florida, which has landed this unique species on the endangered animals list due to human development destroying their habitat at a rapid rate. People have made houses on the sand dunes, proving detrimental to beach mice.
Figure 1: Beach mouse
Credit: J.B. Miller, courtesy of Mother Nature Network Web site at http://www.mnn.com/earth-matters/animals/stories/how-mice-got-their-sandy-coats-beach-life
If a beach mouse were taken out of its environment, it would be difficult to distinguish from a house mouse. They weigh about 12.5 grams and pregnant females can weigh 20 grams. They have dark eyes, large ears, and pale skin. All have predominately white fur but will also have varying levels of brown depending on location. The beach mice in Alabama have the highest levels of brown hue, while the mice in Santa Rosa are the whitest. Their pale skin and white fur is most likely an adaptation to camouflage with sand.
Beach mice only live in sand dunes. They dig multiple burrows in the dunes, creating a home range up to 5000 m2. Home ranges often overlap with other families but each family can have twenty burrows. In each burrow is a long tunnel to act as an entrance on one side and on the other side, is a short tunnel that ends directly below the surface of the sand. By not leaving the back tunnel exposed, the mice can explode through it as an emergency exit in case of predators. Burrows contain a male and female or a female and offspring.
Historically, there are eight subspecies of beach mice with five living on the Gulf Coast and three on Atlantic beaches. The Gulf subspecies are found on keys, barrier islands, or coastal peninsulas ranging from Cape San Blas, Florida and Mobile Bay, Alabama. There are only two Atlantic...