Ictidomys parvidens
Creators: name: Wilson, Don E.
name: Thomas E. Lacher, Jr
name: Mittermeier, Russell A.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Rodentia
Sciuridae
Ictidomys
Ictidomys parvidens

description: 215. Rio Grande Ground Squirrel <i>Ictidomys parvidens</i> <b>French:</b> Spermophile du Rio Grande / <b>German:</b> Rio-Grande-Ziesel / <b>Spanish:</b> Ardilla terrestre de Rio Grande <b>Taxonomy.</b> Spermophilus mexicanus parvidens Mearns, 1896, “Fort Clark, Kinney County, Texas.” Ictidomys parvidens was recently elevated to a distinct species, different from its sister taxon, I. mexicanus. Monotypic. <b>Distribution.</b> SW New Mexico and W Texas (USA), E Coahuila, Nuevo Leon, Tamaulipas, Zacatecas, and an isolated population in Mapimi NE Durango (Mexico). <b>Descriptive notes.</b> Head—body 243-325 mm (males) and 216-303 mm (females), tail 80-130 mm (males) and 80-124 mm (females); weight 100-210 g (males) and 90-152 g (females). The Rio Grande Ground Squirrel is medium-sized and has intricately patterned, olivaceous gray to sepia dorsal pelage, with nine rows of white-to-buff spots extending from head to haunches. Eye rings are white to cream and prominent contrasts to yellowish to cinnamon face and chin. Sides and venter are buff, sometimes suffused with yellow. Tail is grizzled slate-gray, frosted with light color of venter. <b>Habitat.</b> Grassy habitats and grassy shrublandsin arid regions. The Rio Grande Ground Squirrel can live in human-maintained grassy habitats, such as cemeteries, maintained lawns, mowed parks, and golf courses that promote short grass. <b>Food and Feeding.</b> The Rio Grande Ground Squirrel is an opportunistic omnivore, feeding mostly on grass and forb leaves, stems, shoots, tubers, and seeds; cacti flesh and fruits are also consumed. It will eat significant numbers of insects and scavenge animal matter. <b>Breeding.</b> The Rio Grande Ground Squirrellives in burrows that are relatively simple; however, maternity burrows are often more convoluted. Males emerge from hibernation first in March, and females emerge 2—4 weeks later. Mating season can be lengthy extending for 20-71 days in March-April. After gestation of 28-30 days,litters of 2-10 young are born. Juveniles emerge 30-54 days later in late spring or summer and are weaned by August when they disperse from natal areas. <b>Activity patterns.</b> The Rio Grande Ground Squirrelis diurnal and hibernates for c.7 months in relatively simple burrow systems beginning as early late July. Adult males immerge by August, females by September, and young-of-the-year may stay aboveground until October. Where winters are mild, it may stay active year-round. <b>Movements, Home range and Social organization.</b> The Rio Grande Ground Squirrel can live at very low densities and appears to be solitary although tolerant of home range overlap and colonial in good habitat. Loosely structured colonies can occur in high-quality habitat. Aggressive chases are common. Home ranges are less than 90 m in diameter. Alarm calls are short high-pitched trills that elicit vigilance from nearby individuals. <b>Status and Conservation.</b> Not yet been assessed on The [UCN Red List. The Rio Grande Ground Squirrelis likely a species of least concern with a stable population. Major conservation challenge is degradation of rangelands and fragmentation of habitats. It is locally common and can be viewed as a pest that is hunted, trapped, and poisoned and burrows are ploughed. <b>Bibliography.</b> Baudoin et al. (2004), Mandier &amp; Gouat (1996), Schwanz (2006), Thorington et al. (2012), Yancey et al. (1993), Young &amp; Jones (1982).
description: Published as part of <i>Don E. Wilson, Thomas E. Lacher, Jr &amp; Russell A. Mittermeier, 2016, Sciuridae, pp. 648-837 in Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona :Lynx Edicions</i> on page 805, DOI: 10.5281/zenodo.6840226