Geosciurus inauris
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
Geosciurus
Geosciurus inauris

description: 167. South African Ground Squirrel <i>Geosciurus inauris</i> <b>French:</b> Ecureuil du Cap / <b>German:</b> Kap-Borstenhérnchen / <b>Spanish:</b> Ardilla terrestre de Sudéfrica <b>Taxonomy.</b> Sciurus inauris Zimmermann, 1780, “Kaffirland, South Africa.” This species is monotypic. <b>Distribution.</b> Namibia, Botswana, N &amp; C South Africa, and W Lesotho. <b>Descriptive notes.</b> Head-body mean 246-4 mm (males) and 247-4 mm (females), tail 194-211 mm (males) and 196-207 mm (females); weight 423-649 g (males) and 444-600 g¢ (females). The South African Ground Squirrel has sandy cinnamon-brown dorsum, with black skin and longitudinal white stripe running from shoulder to hips; faint eye ring and venter are white. Snout and face are washed with buff to white. Prominent tail is frosted white and dorsoventrally flattened, with two black bands near base. Hair on venteris sparse or absent. Chromosomal numberis 2n = 38 and FN = 70. Karyotype consists of seven pairs of metacentric autosomes, ten pairs of submetacentric autosomes, pair of acrocentric autosomes, medium-sized submetacentric X-chromosome, and small metacentric Y-chromosome. <b>Habitat.</b> Open terrain with sparse vegetation often dominated by annual grasses in arid Karroo areas, grasslands, overgrazed land, floodplains, or seasonally dry watercourses where solid ground is available to burrow. The South African Ground Squirrel also occurs in sand dunes. <b>Food and Feeding.</b> The South African Ground Squirrel is strongly herbivorous; diet shifts from grasses and fruits in wet summer to seeds, fruits, stems, roots, and occasionally insects in winters. <b>Breeding.</b> Reproduction occurs throughout the year but peaks in the dry winter. Small groups of bachelor males search among females for mating opportunities. Females mature at ¢.8 months of age when only one adult female is present in a social group and c.12 months when more than one reproductive female is present. Ovulation is spontaneous, and individuals remain in estrus less than four hours and mate with an average of four males. Females can have up to four litters per year. After a seven-week gestation, females produce 1-4 young in a nest burrow that they dig themselves, away from the group cluster. Lactation lasts an average of 52 days, and young are weaned within c.7 days of joining the larger group. All females in the group devote care to juveniles after they have joined the group. Females that successfully wean their young reenter estrus ¢.56 days after emergence of the litter, while females that lose their litters prematurely come into estrus 24 days after the loss. Natal dispersal is male-biased and occurs at ¢.8-10 months. <b>Activity patterns.</b> The South African Ground Squirrel is diurnal and can tolerate high temperatures using behavioral thermoregulation that permit foraging when temperatures exceed 40°C. Individuals orient away from the sun and use their reflected tail to reduce absorption of the direct rays of the sun. When foraging or vigilant, individuals stand on their toes to increase heat loss and lessen heat gain and will lay outstretched and sparsely haired belly in close contact with shaded and moist earth. If temperatures are too high, they return to their burrows to cool. <b>Movements, Home range and Social organization.</b> The South African Ground Squirrel moves among burrows systems that include up to 30 entrances spread over an area of 200-400 m?. Burrow clusters of individual female groups are often separated by more than 100 m, and thus males must maintain large home ranges up to 12-5 ha. Agonistic behaviors are relatively uncommon, with individuals from different groups typically ignored while feeding within close proximity. Social structure is unique among species of squirrels, with groups segregated by sex in matrilineal kin groups of adult females and mixed-sex groups of subadults that inhabit individual burrow clusters and unrelated assemblies of males that rotate among many burrows. These colonies of males and females are composed of 6-12 individuals but occasionally can exceed 30 individuals under some circumstances. No more than three reproductive females exist at one time in a single female group. As a result, some subadult females will shift to another colony with fewer reproductive females to gain mating opportunities. Males live in vacant burrows except during the breeding season when they move closer to females and attemptto sleep in burrows of female groups. Bachelor groups occupy wide home ranges that span home ranges of several female groups. High-pitched alarm vocalizations are uttered when individuals are threatened or surprised. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. The South African Ground Squirrel is widespread, presumably has large populations, and occurs in a number of protected areas. Population trends are stable, and it is unlikely to be declining fast enough to qualify forlisting in a more threatened category. <b>Bibliography.</b> Bennett et al. (1984), Bouchie et al. (2006), Hayssen (2008a), Herzig-Straschil (1978), Lynch (1983), Marsh et al. (1978), Nel (1975), Skinner &amp; Chimimba (2005), Skurski &amp; Waterman (2005), Smithers (1971), Snyman (1940), Thorington et al. (2012), Van Heerden &amp; Dauth (1987), Waterman (1995, 1996, 1997, 1998, 2002, 2013b), Zumpt (1968, 1970).
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 783, DOI: 10.5281/zenodo.6840226