The Perdido Key beach mouse (''Peromyscus polionotus trissyllepsis'') is an endangered subspecies of the

oldfield mouse The oldfield mouse, oldfield deermouse or beach mouse (''Peromyscus polionotus'') is a nocturnal species of rodent in the family Cricetidae. It is a species of the genus ''Peromyscus'', a closely related group of New World rats and mice, New Wor ...

. It is found on

Perdido Key Perdido Key is a barrier island on the north coast of the Gulf of Mexico. The island extends from Pensacola Pass on the east to Perdido Pass on the west. Most of the island is in Florida, with the western end of the island in Alabama. Santa Ro ...

. The small white and gray mouse, weighing only , blends in well with the white quartz sand of northern Gulf coast beaches.

Diet

Dune plants are the primary source of food for the species. It feeds primarily on the seeds of sea oats and bluestem, but will occasionally eat insects. Unlike other rodents they shun people and will not eat or be near trash.

Reproduction

The Perdido Key beach mouse is a nocturnal animal, spending most daylight hours in their burrows. Unlike many species, beach mice are

monogamous Monogamy ( ) is a relationship of two individuals in which they form a mutual and exclusive intimate partnership. Having only one partner at any one time, whether for life or serial monogamy, contrasts with various forms of non-monogamy (e.g. ...

, with mated pairs tending to remain together as long as both live. A typical beach mouse pair averages 3–4 offspring per litter and has roughly 3 litters per year. Usfws-perdido-key-beach-mouse-large

Shelter

In contrast to its inland relatives, the Perdido Key beach mouse avoids humans, buildings and trash, instead preferring to meander among the dunes near its

burrow file:Chipmunk-burrow (exits).jpg, An eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of Animal lo ...

. Mouse burrows are usually located in the dunes at the base of a shrub, clump of grass or near some vegetated cover. The burrow itself consists of an entrance, a nest cavity, and an escape tube which is closed off but near the surface of the sand. If an intruder, such as a snake or crab, enters a beach mouse burrow, mice make a hasty retreat out the escape tube.

Conservation

The species was listed as an

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

in 1985. Loss of habitat to development is considered to be the main factor which led to the decline of the species. Hurricanes have also taken their toll on the endangered mouse. The beach mouse population at Perdido Key was nearly made extinct in the mid-1990s when hurricanes

Erin Erin is a personal name taken from the Hiberno-English word for Ireland, originating from the Irish word ''"Éirinn"''. "Éirinn" is the dative case of the Irish word for Ireland, "Éire", genitive "Éireann", the dative being used in preposi ...

and

Opal Opal is a hydrated amorphous form of silicon dioxide, silica (SiO2·''n''H2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous (chemical) physical structure, it is classified as a ...

ravaged the key's beaches. Numbering less than 40 after the storms, the mice have regenerated with current population estimates near 500. While populations appear to be growing, the mouse will probably never be delisted because of continued

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

and degradation.

References

{{Taxonbar, from=Q5475417 Peromyscus Pensacola metropolitan area Mammals described in 1968 Endemic rodents of the United States