237.

Plains Harvest Mouse

Reithrodontomys montanus

French: Souris-moissonneuse des plateaux / German: Steppen-Erntemaus / Spanish: Raton espiguero de llanura

Taxonomy. Reithrodon montanus Baird, 1855, “vicinity of the Rocky Mountains,lat. 38°.” Restricted byJ. A. Allen in 1895 to “near the upper end of the San Luis Valley in Colorado,” USA.

Reithrodontomys montanus is in subgenus Reithrodontomys . Three subspecies recognized.

Subspecies and Distribution.

R.m.montanusBaird,1855—SCColorado,SEArizona,WC&SNewMexico,andSWTexas(USA),andNESonora,Chihuahua,andextremeNCDurangostates(NMexico).

R.m.albescensCary,1903—SEMontana,SWNorthDakota,EWyoming,W&SSouthDakota,mostofNebraska,EColorado,WKansas,extremeNENewMexico,andextremeNW&NCOklahoma(USA).

R. m. griseus Bailey, 1905 — SE Nebraska, E Kansas, Oklahoma, extreme SW Missouri, extreme NW Arkansas, and Texas (USA).

Descriptive notes. Head-body 55-65 mm, tail 54-65 mm, ear 13-17 mm, hindfoot 15-17 mm; weight 7-9 g. The Plains Harvest Mouse is one of the smallest species of Reithrodontomys . Dorsum is pale grayish brown, sprinkled with fulvous and black hairs. It has prominent dark mid-dorsal stripe. Venter is white. Tail is either equalto or shorter than head-body length, which is diagnostic; tail has pronounced black stripe bordered by white hairs.

Habitat. Grasslands, especially in areas dominated by meadows with abundant blue gramma ( Bouteloua gracilis, Poaceae) and other species of perennial grasses, riparian areas, and abandoned crop fields at elevations of 1200-1920 m (most records are near lower elevation).

Food and Feeding. Plains Harvest Mice are insectivorous and herbivorous. They reportedly eat grasshoppers, grass, seeds, and fruits of cacti.

Breeding. The Plains Harvest Mouse has an average of four offspring per litter (range 1-9). Gestation is 21 days. Young are altricial at birth. Oval-shaped nests (110 x 80 mm) lined with grasses and soft leaves are constructed between shrubs, under fallen logs, or between rocks.

Activity patterns. The Plains Harvest Mouse is nocturnal and terrestrial.

Movements, Home range and Social organization. Home ranges in Texas range between 0-23 ind/ha and 0-84 ind/ha. Densities are 1-5 ind/ha.

Status and Conservation. Classified as Least Concern on The IUCN Red Lust.

Bibliography. Allen (1895a), Anderson (1972), Bailey (1905), Baird (1855b), Brown (1946), Cary (1903), Davis (1974), Hall (1981), Hooper (1952a), Maxwell & Brown (1968), Moulton et al. (1981), Téllez & Sanchez (2014b), Waggoner (1975), Wilkins (1986).