{{short description|Species of mammal}} {{Use dmy dates|date=April 2017}} {{Use South African English|date = February 2020}} {{speciesbox | name = Cape ground squirrel | image = Cape ground squirrel, Xerus inauris, at Krugersdorp Game Reserve, Gauteng, South Africa (27410204561).jpg | image_caption = At Krugersdorp Game Reserve, South Africa | status = LC | status_system = IUCN3.1 | status_ref = <ref name=iucn>{{cite iucn |author=Cassola, F. |year=2016 |errata=2017 |title=''Xerus inauris'' |article-number=e.T23145A115167437 |doi=10.2305/IUCN.UK.2016-3.RLTS.T23145A22252885.en}}</ref> | genus = Geosciurus | species = inauris | authority = (Zimmerman, 1780) | range_map = Xerus inauris range map.png | range_map_caption = Cape ground squirrel range | synonyms = ''Xerus inauris'' }}
The '''Cape ground squirrel''' or '''South African ground squirrel'''<ref name=iucn /><ref name="Thorington">{{MSW3 Sciuridae|id= 12400716|page= 790}}</ref> ('''''Geosciurus inauris''''')<ref>{{Cite taxon |asm |title=''Geosciurus inauris'' (E. A. W. von Zimmermann, 1780) |id=1001835 |access-date=2025-03-15}}</ref> is found in most of the drier parts of southern Africa from South Africa, through to Botswana, and into Namibia, including Etosha National Park.
The name ''Cape'' ground squirrel is somewhat misleading as it actually has a much wider area of habitation. This common name may have been arrived at to distinguish it from a tree squirrel (the eastern grey squirrel) found around Cape Town, which was imported from Europe by Cecil John Rhodes.
The species has also been known as the '''fan-tailed squirrel'''.
==Description== alt=Cape ground squirrel looking out of its burrow|thumb|Cape ground squirrel looking out of its burrow [[File:The fan tailed squirrel (cropped).jpg|thumb|''The Fan-tailed Squirrel''.<br />From an original painting by the Hon. Alice Foljambe<ref>{{cite Wikisource |title=Notes and Comments |wslink=Animal Life and the World of Nature/1903/06/Notes and Comments |first1=Alice Etheldreda Georgiana Mary |last1=Foljambe |date=June 1903 |author-link1=Alice Etheldreda Georgiana Mary Foljambe}}</ref> ]]
The Cape ground squirrel has black skin with a coat made of short stiff hairs without underfur. The fur is cinnamon on the back while the face, underbelly, sides of neck and ventral sides of limbs are white.<ref name=Skurski2005>Skurski, D., J. Waterman. 2005. "Xerus inauris", ''Mammalian Species'' 781:1-4.</ref> The sides of its body each have a white stripe that stretches from the shoulders to the thighs. The eyes are fairly large and have white lines around them. The pinnae are small. The tail is flattened on the back and underside and is covered with white hair and two black bands at the base.<ref name=Skinner1990>Skinner J. D., R. H. N. Smithers. 1990. ''The mammals of southern African subregion'', University of Pretoria.</ref> The Cape ground's sexual dimorphism is subtle. Males usually weigh {{convert|423|-|649|g|lb}}, 8 to 12 percent more than females at {{convert|444|-|600|g|lb}}.<ref>Lynch C. D. 1983. "The mammals of the Orange Free State", ''Memoirs van die Nasionale Museum'' 18:58-60.</ref> Male Cape ground squirrels have a total length of {{convert|424|–|476|mm|in}}, while females are {{convert|435|-|446|mm|in}} long.<ref name=Skurski2005/> The dental formula of the ground squirrel is {{DentalFormula|upper=1.1.0.0|lower=1.1.3.3}}.<ref name=Zumpt1970>Zumpt I. F. 1970. "The ground squirrel", ''African Wild Life'' 24:115-121.</ref> The belly and groin area of the females each have two pairs of mammary glands. The glans penis of the males are large with a prominent baculum.<ref name=Skurski2005/> This species is notable for its impressively large testicles, which are roughly golf ball size, around 20% of the length of the head and body.<ref name=Zumpt1970/> Moulting occurs between August and September and between March and April, once per year.<ref name=Herzig1978/>
==Distribution== The Cape ground squirrel is widespread in southern Africa; through Botswana, South Africa, Lesotho, and Namibia.<ref name=iucn/><ref name=Herzig1979>Herzig-Straschil B. 1979. "''Xerus inauris'' (Rodentia, sciuridae)-an inhabitant of arid regions of southern Africa", ''Folia Zoologica'' 28:119-124.</ref> Its range covers most of Namibia but is absent from coastal regions and the northwest.<ref name=Skinner1990/> Ground squirrels inhabit central and southwestern Kalahari in Botswana.<ref name=Smithers1971>Smithers R. H. N. 1971. ''The mammals of Botswana'', Salisbury, Rhodesia, Museum Memoirs No. 4.</ref> In South Africa, it can be found in central and north-central areas.<ref name=Skinner1990/>
==Behaviour and ecology== Cape ground squirrels live mainly in arid or semiarid areas.<ref name=Herzig1978/> They prefer to live in veld and grasslands with hard ground. They can also be found in scrub along pans, on floodplains and in agricultural areas.<ref name=Smithers1971/> Ground squirrel are generally active during the day and do not hibernate. They are burrowing animals that dig and live in clusters of burrows averaging around {{convert|700|m2|sqft}}<ref name=Waterman1995>Waterman, J. M. 1995. "The social organization of the Cape ground squirrel (''Xerus inauris''; Rodentia: Sciuridae)". ''Ethology'' 101:130–147.</ref> with 2-100 entrances.<ref name=Herzig1978>{{cite journal |last1=Herzig-Straschil |first1=Barbara |title=On the biology of ''Xerus inauris'' (Zimmermann, 1780) (Rodentia, Sciuridae) |journal=Zeitschrift für Säugetierkunde |date=1977 |volume=43 |pages=262–278 |url=https://www.biodiversitylibrary.org/part/191466#/summary}}</ref> Burrows serve to protect the squirrel from extreme temperatures at the surface as well as predators. Nevertheless, most of the day is spent feeding at the surface.<ref name=Herzig1979/> Squirrels shade their head and back with their bushy tails, which was originally thought to be important for thermoregulation. However, research has revealed that tail raising does not actually decrease core body temperature and seems to mostly serve as a way for squirrels to cool the skin and increase their thermal comfort as they forage in the hot sun in between visits to their burrows.<ref name=":0">{{Cite journal |last1=Fick |first1=L.G. |last2=Kucio |first2=T. A. |last3=Mathee |first3=A. |last4=Mitchell |first4=D. |date=2009 |title=The relative roles of the parasol-like tail and burrow shuttling in thermoregulation of free-ranging Cape ground squirrels, Xerus inauris |journal=Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology |volume=152 |issue=3 |pages=334–340 |doi=10.1016/j.cbpa.2008.11.004|pmid=19041951 }}</ref> Burrowing has been shown to reduce the squirrel's core body temperature by a few degrees Celsius.<ref name=":0" /> Squirrels tend to leave the burrows earlier in the morning in the summer months to avoid the heat, and in the winter months their core body temperature increases rapidly upon exiting their burrows.<ref name=":1">{{Cite journal |last1=Scantlebury |first1=M |last2=Danek-Gontard |first2=M |last3=Bateman |first3=P. W. |last4=Bennett |first4=N. C. |last5=Manjerovic |first5=M. |last6=Joubert |first6=K. |last7=Waterman |first7=J. |date=2012 |title=Seasonal Patterns of Body Temperature Daily Rhythms in Group-Living Cape Ground Squirrels Xerus inauris |journal=PLOS ONE |volume=7 |issue=4 |article-number=e36053 |doi=10.1371/journal.pone.0036053|pmid=22558324 |pmc=3338621 |bibcode=2012PLoSO...736053S |doi-access=free }}</ref> Dust bathing is also done.
Ground squirrels eat bulbs, fruits, grasses, herbs, insects and shrubs.<ref name=Skurski2005/> They forage daily and do not hoard food.<ref name=Herzig1978/> The Cape ground squirrel usually does not need to drink as it gets sufficient moisture from its food.<ref name=Skurski2005/> A ground squirrel's daily activities are made of around 70% feeding, 15-20% being vigilant and around 10% socializing.<ref name=Herzig1978/><ref name=Waterman1995/> The squirrels use the position of the sun as an orientation marker to hide and recover their food.<ref>{{cite journal |last1= Samson|first1= Jamie|last2= Manser|first2= Martha B.|date= 2016-09-01|title= Use of the sun as a heading indicator when caching and recovering in a wild rodent|journal= Scientific Reports|volume= 6|article-number= 32570|doi= 10.1038/srep32570|pmid= 27580797|pmc= 5007651|bibcode= 2016NatSR...632570S}}</ref>
The burrows of Cape ground squirrels are also used by meerkats and yellow mongooses.<ref name=Waterman2007>Waterman, J., J. Roth. 2007. "Interspecific associations of Cape ground squirrels with two mongoose species: benefit or cost?". ''Behavioral Ecology and Sociobiology'', 61(11):1675-1683.</ref> While Cape ground squirrels and meerkats appear to have a mutual relationship, mongoose and squirrel relations appear to be more commensal.<ref name=Waterman2007/> Predators of ground squirrels include jackals, snakes and monitor lizards. Ground squirrels may be able to scent the differences in the dropping of predators and non-predators.<ref>Belton, L., N. Ball, J. Waterman, P. Bateman. 2007. "Do Cape ground squirrels (''Xerus inauris'') discriminate between olfactory cues in the faeces of predators versus non-predators?", ''African Zoology'', 42(1): 135-138.</ref> When threatened by predators ground squirrels engage in mobbing behaviour:<ref name=Waterman2007/><ref name=Waterman1997>Waterman, J. M. 1997. "Why do male Cape ground squirrels live in groups?" ''Animal Behaviour'' 53:809–817.</ref> several squirrels rush at the predator while using their bushy tails to block it. When the predator strikes back, all the squirrels back off. However, multiple mobbings are usually successful in driving away predators.<ref name=Waterman1997/>
===Social behaviour=== thumb|Cape ground squirrels live in groups of two to three adult females and a maximum of nine sub-adults of either sex
Cape ground squirrels live in groups of two to three adult females and a maximum of nine sub-adults of either sex<ref name=Waterman1995/> as well as the females' dependent offspring.<ref name=Herzig1978/> Groups that have more than three females split into smaller groups.<ref>{{cite journal |last1=Waterman |first1=Jane M. |title=Delayed maturity, group fission and the limits of group size in female Cape ground squirrels (Sciuridae: ''Xerus inauris'') |journal=Journal of Zoology |date=2006 |volume=256 |issue=1 |pages=113–120 |doi=10.1017/S0952836902000146}}</ref> Adult males live separately from females and only join when the females are in estrus.<ref name=Waterman1995/> Male groups number up to 19 unrelated individuals, which are not agonistic. Within a male group, four to five males may form temporary subgroups that change size and members each day.<ref name=Skurski2005/> Female groups live in separate burrow clusters. A female group's home range is c. {{convert|4|ha|acre}} with core areas of around {{convert|0.25|ha|acre}}.<ref name=Waterman1995/> Home ranges can overlap. Core areas are defended by agonistic behaviour.<ref name=Herzig1979/><ref name=Waterman1995/> Male groups live in home ranges envelop those of several female groups and average {{convert|12.1|ha|acre}}.<ref name=Waterman1995/> Within a female group there is no dominance hierarchy, and members use the same feeding and sleeping ranges. Male groups, by contrast, live in ages-based linear hierarchies. Competition between males usually takes the form of leaping displays that cause no injuries.<ref name=Waterman1998>{{cite journal |last1=Waterman |first1=Jane M. |title=Mating tactics of male Cape ground squirrels, ''Xerus inauris'': consequences of year-round breeding |journal=Animal Behaviour |date=1998 |volume=56 |issue=2 |pages=459–466 |doi=10.1006/anbe.1998.0780|pmid=9787037 |s2cid=38692812 }}</ref> Unlike female groups, male groups are not territorial, and membership is very open.<ref name=Skurski2005/> During oestrus, a female will be approached, solicited and chased by males trying to mate with her. The most dominant males get the first matings.<ref name=Waterman1998/> A female will mate with the same male several times. If a male has not yet mated with a female, he will disrupt the copulations she has with other males.<ref name=Waterman1998/> However, mate guarding is rare.
===Communication===
When perceiving something as a threat, ground squirrels will emit a whistle-like call as an alarm call.<ref name=Zumpt1970/><ref name=Herzig1979/> The alarm call comes in two forms; the short and shrill "bi-jo" which signals serious danger, and a medium-pitched "bi-joo" sound which is used for lesser dangers.<ref name=Zumpt1970/> During antagonistic encounters, squirrels emit deep growls as signs of aggression.<ref name=Herzig1979/> Juvenile squirrels make play calls, nest-chirpings, and protest squeaks.<ref name=Skurski2005/>
===Reproduction=== alt=Cape ground squirrel on a tree|thumb|Cape ground squirrel on a tree Cape ground squirrel mate and reproduce year-round<ref name=Herzig1978/><ref name=Smithers1971/><ref name=Waterman1996>{{cite journal |last1=Waterman |first1=Jane M. |title=Reproductive biology of a tropical, non-hibernating ground squirrel |journal=Journal of Mammalogy |date=1996 |volume=77 |issue=1 |pages=134–146 |doi=10.2307/1382715|jstor=1382715 |doi-access=free }}</ref> but mating occurs mostly in dry winter months.<ref name=Skurski2005/> Since females copulate with multiple males, the males' large testes are useful for sperm competition. After copulation, males will masturbate, which could serve to keep the genitals clean and reduce the risk of sexually transmitted infections.<ref>{{Cite journal | doi=10.1371/journal.pone.0013060| pmid=20927404| pmc=2946931| bibcode=2010PLoSO...513060W| title=The Adaptive Function of Masturbation in a Promiscuous African Ground Squirrel| year=2010| vauthors=Waterman JM| journal=PLOS ONE| volume=5| issue=9| article-number=e13060| doi-access=free}}</ref> In groups, only one female at a time enters oestrus which lasts around three hours. Gestation lasts around 48 days<ref name=Waterman1996/> or 42–49 days.<ref name=Zumpt1970/> Lactation begins not long before the pups are born. A lactating female isolates herself in a separate burrow to care for their young but she returns to her group after weaning or if her litter is lost for some reason.<ref name=Skurski2005/> There are 1-3 pups in a litter.<ref name=Herzig1978/><ref name=Waterman1996/> They are born altricial, hairless and blind.<ref name=Herzig1978/> The pups stay in the burrows for their first 45 days. By 35 days, the eyes are open.<ref name=Herzig1978/> Seven days after emerging from the burrows, the pups can eat solid food. Lactation ends at around 52 days.<ref name=Waterman1996/> Males reach sexual maturity at eight months while female mature at 10 months. The former leave their natal groups while the latter remain.<ref name=Waterman1995/>
==Status== The Cape ground squirrels populations does not seem to be threatened overall. In some areas, it is persecuted as an agricultural pest.<ref name=iucn/> In addition, humans have used poisonous grass to control ground squirrel due to crop damage and rabies.<ref name=Zumpt1970/> It inhabits protected areas, such as Kgalagadi Transfrontier Park in Botswana and South Africa and Etosha National Park in Namibia.<ref name=iucn/>
==Gallery== <gallery mode="packed" heights="175px" caption=""> File:Xerus inauris.JPG|Young Cape ground squirrels File:Erdhörnchen 011.jpg|Ground squirrel at burrow entrance File:Xerus inauris 1.jpg| Cape ground squirrels File:Cape ground squirrel (Xerus inauris) male.gif| Male eating, Tswalu Kalahari Reserve, South Africa </gallery>
==References== {{Reflist}}
{{S. Xerinae nav}} {{Taxonbar|from1=Q125863341|from2=Q609173}}
Category:Geosciurus Category:Mammals described in 1780 Category:Mammals of Botswana Category:Mammals of Lesotho Category:Mammals of Namibia Category:Mammals of South Africa Category:Rodents of Africa Category:Taxa named by Eberhard August Wilhelm von Zimmermann Category:Taxobox binomials not recognized by IUCN <!-- Geosciurus inauris -->