190.

White-throated Woodrat

Neotoma albigula

French: Néotoma a gorge blanche / German: \WeiRkehl-Buschratte / Spanish: Rata de bosque de garganta blanca

Taxonomy. Neotoma albigula Hartley, 1894, vicinity of Fort Lowell (near Tucson), Pima County, Arizona, USA .

Historically, 15 subspecies of N. albigula were recognized, but recent taxonomic revisions placed eastern and south-eastern populations (durangae, latifrons, leucodon, melas, robusta, subsolana, and warreni) in N. leucodon, and other authors placed south-western populations ( melanura) in N. melanura . Seven subspecies recognized.

Subspecies and Distribution.

N.a.albigulaHartley,1894—fromextremeSENevada,Arizona,andmostofNewMexico(SWUSA)SintoNESonoraandCChihuahuastates(NMexico).

N.a.brevicaudaDurrant,1934—restrictedtosmallisolatedareaalongtheUtah—Coloradoborder(WUSA).

N.a.laplataensisF.W.Miller,1933—SEUtah,SWColorado,NArizona,andNWNewMexico(SWUSA).

N.a.mearnsiGoldman,1915—smallregioninextremeSWArizona(SWUSA).

N.a.seriTownsend,1912—restrictedtoTiburonIintheSeaofCortez(NWMexico).

N.a.sheldoniGoldman,1915—smallregioninextremeNESonoraState(NWMexico).

N. a. venusta True, 1894 — SE Californa, extreme S Nevada, and W Arizona (SW USA) and extreme NE Baja California and NW Sonora states (NW Mexico).

Descriptive notes. Head—body 206-215 mm, tail 76-185 mm, ear 28-30 mm, hindfoot 30-39 mm; weight 145-350 g. The White-throated Woodratis large and similar to other species of woodrats. Dorsum is grayish brown, with light brown and orange shades. Pelage turns ocherous with increasing age. Venter pelage is plumbeous at base and white-tipped. Throat hairs are diagnostically white to bases. Tail is bicolored, brownish above and whitish below, and sparsely haired. Feet are covered with whitish hair, except for soles. Skull is broad, and anterointernal reentrant angle of M' is shallow.

Habitat. Variety of habitats including arid areas and thorn scrublands, and lesser densities in conifer forests and pastures with some shrubby vegetation, from sea level to elevations of ¢.2475 m.

Food and Feeding. Diet varies according to habitat and season but generally include a mix of succulents such as prickly pear ( Opuntia, Cactaceae) and other cacti. Whitethroated Woodrats also eat herbs, leaves of izote ( Yucca, Asparagaceae), fruits, and inflorescences. Most mammals suffer physiological problems when their diet consists only of cacti because these plants are rich in oxalic acids, but this species can consume large amounts of prickly pear due to its unique intestinal flora. White-throated Woodrats do not require free water because they obtain what they need from succulents.

Breeding. Reproduction occurs in January-July, and probably depends on resources and rainfall. White-throated Woodrats can have more than one litter of 1-3 young each year. Gestation is 38 days, and young are weaned within 27-40 days. Sexual maturity is reached at 80 and 100 days of age for females and males, respectively.

Activity patterns. The White-throated Woodrat is nocturnal but also active during the day . It is terrestrial but adept at climbing bushes and columnar cacti.

Movements, Home range and Social organization. White-throated Woodrats dig burrows at bases of trees, shrubs, rocks, and cacti and generally construct middens with thorny plants (e.g. chollas, Cylindropuntia, Cactaceae; prickly pear; and mesquite, Prosopis, Fabaceae), leaves, and stones to protect entrances.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Whitethroated Woodrats are very tolerant of environmental variation and are adaptable to anthropogenic activities. They have a wide distribution, which probably ensures survival of all subspecies. The Tiburon Island subspecies (seri) is classified as threatened in Mexico and should be monitored.

Bibliography. Bradley & Mauldin (2016), Brylski, P (1990b), Durrant (1934), Edwards et al. (2001), Goldman (1915b), Hall (1981), Hartley (1894), Hoffmeister (1986), Jameson & Peeters (1988), Macédo & Mares (1988), Mellink & Luéevano (2014), Miller (1933), Townsend (1912), True (1894b).