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Catalina Deermouse

Peromyscus slevini
CR · Critically endangered Rodentia Cricetidae
Size
8-10 cm + tail 8-10 cm
Weight
20-30 g
Activity
Nocturnal
Sociability
Solitary

Description

Found solely on a tiny island in the Gulf of California, Santa Catalina, an enclave so isolated that it has evolved its own community of unique species, including a rattlesnake world-renowned for lacking a functional rattle. It shares with that snake and other endemic island species the same fate: survival dependent entirely on a territory that can be crossed in a single day. Its name honours an American herpetologist and naturalist who documented much of the wildlife of the Gulf of California islands in the early 20th century. It is one of many examples of how these islands, despite their small size, harbour an endemic biodiversity disproportionate to their area.

How to identify it

A small rodent with greyish-brown fur on the upperparts and white on the underparts, large eyes and well-developed ears. It differs from other species of Peromyscus in the Gulf of California by its exclusive restriction to Santa Catalina Island, with no overlap with any other island or mainland population.

Signs and tracks

Small track, 1.3-1.8 cm, showing 4 front toes and 5 hind toes. Small, elongated droppings 3-5 mm long, left scattered along surface runways through the island's arid scrub vegetation. It digs shallow burrows beneath rocks or roots, the entrance semi-hidden among dense vegetation.

Habitat and range

Arid scrub on a desert island, in lowlands. Endemic to Santa Catalina Island in the Gulf of California, Mexico, with no natural presence outside this island.

Diet

Omnivorous, feeding on seeds, leaves and invertebrates from the arid scrubland of its island home.

Behaviour

Solitary and nocturnal, with a home range centred on shelters among rocks and dense vegetation on its island home.

Conservation

Its restriction to a single, tiny island, combined with the constant threat of introduced predators such as cats, leaves its populations extremely vulnerable.

Threats

Risk of introduction of cats, rats or other predators to Santa Catalina Island, and the species' extreme geographical restriction to a tiny island territory.

Other accounts in Cricetidae

See all species accounts for rodents · Full species index

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