8.

Pacific Degu

Octodon pacificus

French: Octodon de Mocha / German: Pazifikdegu / Spanish: Degu de Isla Mocha

Other common names: Mocha Degu, Mocha Island Degu

Taxonomy. Octodon pacificus Hutterer, 1994,

“Isla Mocha (38°22’ S, 73°55’ W), Arauca Province,” Bio Bio, Chile .

This species is monotypic.

Distribution. Mocha I (38°22’ S, 73°55’ W, Bio Bio Region, SC Chile).

Descriptive notes. Head-body 125-195 mm, tail 165-170 mm; weight 290 g (based on two available specimens). Tail is long (74-77% of head-body length) and ends in an inconspicuous tuft with black hairs. The Pacific Degu is larger and heavier than other species of Octodon . Ears are relatively short and dark. Pelage is soft and long. Dorsal color is orange-coffee; venter is lighter. Karyotype is unknown.

Habitat. Dense subtropical or tropical, moist, lowland forest, biogeographically related to mainland Valdivian forest at elevations of 390 m.

Food and Feeding. The Pacific Degu is herbivorous and eats leaves, seeds, and grasses.

Breeding. Reproductive activity of the Pacific Degu apparently begins in September, and offspring are born in December.

Activity patterns. The Pacific Degu is diurnal.

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. Classified as Critically Endangered on The IUCN Red List. Extent of occurrence of the Pacific Degu is less than 100 km?, and its area of occupancy is less than 10 km? Its distribution is severely fragmented, and there is continuing decline in the extent and quality ofits habitat. Major threat is habitat loss by deforestation. Islanders rely heavily on vegetation for their subsistence, which has led to significant degradation of natural habitats. Scientists had not seen the Pacific Degu since its description in 1994, but an expedition in December 2015 found a pregnant specimen that had been dead for c.2 days. Dueto its very restricted habitat, studies are urgently needed on its ecology and degree of conservation threat.

Bibliography. Cofré & Marquet (1999), Espinoza (2016), Hutterer (1994), Iriarte (2008), Munoz-Pedreros (2000), Ojeda & Bidau (2008d).