White-throated Woodrat

White-throated Woodrat, Neotoma albigula

White-throated Woodrat, Neotoma albigula. Photograph taken within the greater Palm Springs area of southern California, March 2021. Photograph courtesy of Dr. Tom Bartol, Carlsbad, California.

The White-throated Woodrat, Neotoma albigula, is a member of the Cricetidae Family of true hamsters, voles, lemmings, muskrats, and New World rats and mice. The Cricetidae Family consists of seven hundred six species placed into one hundred forty-one genera and six subfamilies. There are twenty-three species in the Neotoma genus. In Mexico, they are known as Rata-cambalachera Garganta Blanca.

White-throated Woodrats have a medium-sized body with grayish brown fur on their dorsum. Their ventral side is light gray with white on their throat. Their tail is shorter than the length of their body, bi-colored, and covered in moderately long fur. They have large, rounded, and hairless ears. Body size varies depending upon the climate, with larger individuals found in colder regions and smaller individuals found in warmer regions. In general, they have an average snout to vent length of 33 cm (13 inches) and weigh 197 g (7 oz). Black color morphs of the White-throated Woodrat occur on lava beds in Texas and New Mexico, United States. This species displays no significant sexual dimorphism.

While White-throated Woodrats are primarily nocturnal, they demonstrate diurnal behavior within their den. In general, two types of dens are constructed. In rocky areas, plant litter is piled around a crevice. Spiny plants such as cholla, prickly pear, mesquite, and catclaw are favored, likely due to the added protection from predators they afford. Dens may also be constructed against or beneath shrubs and cacti, preferably those having much cover near the ground. These dens can become quite large, reaching 1 m (3 feet) high and 3 m (10 feet) in diameter. Within each den is a compact, cup-shaped nest composed of shredded dry leaves, blades of grass, and weed stems. Feces is not deposited within the nest or den, rather, it is deposited in a single area outside in the vicinity of the den. White-throated Woodrats remain active year round and while they may be found near one another, they are a primarily solitary species. Only a single individual, or a female and her young, occupy a den. Home ranges and feeding territories often overlap considerably, but dens are not shared. Social interactions only occur between adults during the mating season. While the exact timing of their mating season varies slightly throughout their range, it generally occurs from January to September. Breeding slows during the hottest months of the year. Females produce at least two (possibly three or more) litters per season, each consisting of two to three pups. Gestation lasts approximately 30 days and it is not uncommon to find a female with offspring of two different ages in her den. Pups grow rapidly and are weaned at 62 to 72 days of age. Males reach sexual maturity by 100 days of age, while females may reproduce as early as 80 to 87 days. They live up to three years in the wild and up to six years in captivity.

White-throated Woodrats are generalist herbivores and consume cacti, mesquite, forbs, and grasses. Occasionally, they may consume animal material such as ants, beetles, and grasshoppers. Cacti are an important part of their diet, as it supplies them with most of their water intake. During the driest months of the year, up to 90% of their diet consists of water rich cacti. They are preyed upon by coyotes, ringtails, bobcats, foxes, raccoons, skunks, hawks, owls, and snakes. Woodrat dens are frequented by a variety of arthropods, and some may be parasitized by bot fly larvae and fleas.

The White-throated Woodrat occurs throughout the southwestern United States and central Mexico. In the United States, they are found in extreme southwestern Utah, southwestern Colorado, southeastern California, Arizona, and western New Mexico. In Mexico they are found in northeastern Baja California, Sonora, Chihuahua, and northern Sinaloa. Additionally, they inhabit Tiburon and Turner Islands.

The White-throated Woodrat can be found at elevational ranges that extend from sea level to approximately 2,500 m (8,200 feet). They prefer arid areas including rocky mountainsides, scrubland, cactus flats, pinyon-juniper woodlands, and desert habitats.

The White-throated Woodrat may be confused with the Cactus Mouse, Peromycus eremicus, due to their similar appearances and overlapping ranges. The Cactus Mouse is smaller in size with a brownish to cinnamon coat. Their tail is sparsely furred with a slight tuft at the tip. While White-throated Woodrats are known for their distinctive dens, Cactus Mice nest in wood piles, rock piles, or the abandoned burrows of other animals.

From a conservation perspective, the White-throated Woodrat is current considered to be of Least Concern, with a wide distribution, large population size, and tolerance of a broad range of habitats. The population found on Tiburon Island is considered Threatened in Mexico. No major threats have been identified for this species.