View source for Biology:Red squirrel

{{short description|Species of tree squirrel common throughout Europe and Asia}}
{{Speciesbox
| name = Red squirrel
| image = Squirrel posing.jpg
| image_caption = Near Alverstone, Isle of Wight
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name=iucn>{{cite iucn |title=''Sciurus vulgaris'' |name-list-style=amp |author=Shar, S. |author2=Lkhagvasuren, D. |author3=Bertolino, S. |author4=Henttonen, H. |author5=Kryštufek, B. |author6=Meinig, H. |page=e.T20025A115155900 |year=2016 |errata=2017 |doi=10.2305/IUCN.UK.2016-3.RLTS.T20025A22245887.en |access-date=9 March 2022}}</ref>
| genus = Sciurus
| species = vulgaris
| authority = [[Biography:Carl Linnaeus|Linnaeus]], [[Biology:10th edition of Systema Naturae|1758]]
| subdivision_ranks = Subspecies
| subdivision_ref = <ref name="Thorington">{{MSW3 Sciuridae | id = 12400219 | page=764 | heading = ''Sciurus (Sciurus) vulgaris''}}</ref>
| subdivision = 23 recognized, see [[Biology:Red squirrel#Taxonomy|text]]
| range_map = Sciurus vulgaris habitat.png
| range_map_caption = Red squirrel range
}}

The '''red squirrel''' or '''Eurasian red squirrel''' ('''''Sciurus vulgaris''''') is a [[Biology:Species|species]] of tree squirrel in the [[Biology:Genus|genus]] ''[[Biology:Sciurus|Sciurus]]'' common throughout [[Earth:Eurasia|Europe and Asia]]. The red squirrel is an arboreal, primarily herbivorous [[Biology:Rodent|rodent]].

In Great Britain, Ireland, and in Italy numbers have decreased drastically in recent years.<ref>{{Cite web|title=Why is the Red squirrel declining in the UK & what can be done? {{!}} Wildlife Online|url=https://www.wildlifeonline.me.uk/questions/answer/why-is-the-red-squirrel-declining-in-the-uk-and-what-can-be-done|access-date=2021-04-17|website=www.wildlifeonline.me.uk|language=en}}</ref> This decline is associated with the introduction by humans of the eastern grey squirrel (''Sciurus carolinensis'') from [[Earth:North America|North America]]. However, the population in Scotland is stabilising<ref>{{cite news |url=https://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-42987025|access-date=7 March 2018|title=Scotland's red squirrel numbers stabilise|date=8 February 2018|work=BBC News}}</ref> due to conservation efforts, awareness and the increasing population of the pine marten, a European predator that selectively controls grey squirrels.<ref>{{cite news|title=Red squirrel numbers boosted by predator|url=https://www.bbc.co.uk/news/science-environment-43308588|first=Victoria|last=Gill|date=7 March 2018|work=BBC News}}</ref><ref>{{Cite web | url=https://www.vwt.org.uk/species/pine-marten/ | title=Pine marten |publisher= the Vincent Wildlife Trust}}</ref>

==Description==
[[File:Squirrel (17026400639).jpg|thumb|Underparts are generally white-cream-coloured]]
[[File:MattiParkkonen Orava.jpg|thumb|Profile of the Eurasian red squirrel in grey winter coat]]
[[File:Sciurus vulgaris 02 MWNH 579.jpg|thumb|Skull of a red squirrel]]
The red squirrel has a typical head-and-body length of {{convert|19|to|23|cm|in|frac=2|abbr=on}}, a tail length of {{convert|15|to|20|cm|in|frac=2|abbr=on}}, and a mass of {{convert|250|to|340|g|oz|frac=2|abbr=on}}. Males and females are the same size. The Eurasian red squirrel is somewhat smaller than the American eastern grey squirrel, which has a head-and-body length of {{convert|25|to|30|cm|in|frac=2|abbr=on}} and weighs between {{convert|400|and|800|g|lboz|abbr=on}}.

The long tail helps the squirrel to balance and steer when jumping from tree to tree and running along branches and may keep the animal warm during sleep.<ref>{{cite web|url=http://www.britishredsquirrel.org/red-squirrels/characteristics/|title=Characteristics – British Red Squirrel|website=britishredsquirrel.org|access-date=27 March 2018}}</ref>

The red squirrel, like most tree squirrels, has sharp curved [[Biology:Claw|claw]]s to help it to climb and descend broad tree trunks, thin branches, and even house walls. Its strong hind legs let it leap gaps between trees. The red squirrel also can swim.<ref>[http://rsst.org.uk/about-us/red-squirrel-facts/ Red squirrel facts]. RSST. Retrieved on 30 September 2013.</ref>

The coat of the red squirrel varies in colour with time of year and location. There are several coat colour morphs ranging from black to red. Red coats are most common in Great Britain; in other parts of Europe and Asia [[Biology:Polymorphism|different coat colours]] coexist within populations, much like hair colour in some human populations. The underside of the squirrel is always white-cream in colour. The red squirrel sheds its coat twice a year, switching from a thinner summer coat to a thicker, darker winter coat with noticeably larger ear-tufts (a prominent distinguishing feature of this species) between August and November. A lighter, redder overall coat colour, along with the ear-tufts (in adults) and smaller size, distinguish the red squirrel from the eastern grey squirrel.<ref>[http://www.scottishsquirrels.org.uk/docs/008__030__general__SSRS_TwoSquirrels_Factsheet_FINAL__1257509087.pdf Two different squirrels: the facts] {{Webarchive|url=https://web.archive.org/web/20131001005141/http://www.scottishsquirrels.org.uk/docs/008__030__general__SSRS_TwoSquirrels_Factsheet_FINAL__1257509087.pdf |date=1 October 2013 }}. scottishsquirrels.org.uk. Retrieved on 25 July 2013.</ref><ref>[http://www.rspb.org.uk/community/wildlife/f/13609/t/9105.aspx RSPB facts]. Rspb.org.uk (24 January 2010). Retrieved on 25 July 2013.</ref> The red colour offers camouflage when seen against the bark of pine trees.{{citation needed|date=March 2021}}

==Distribution and habitat==
[[File:Red Squirrel Urals.jpg|thumb|Red squirrel in the Urals region, grey winter coat]]
Red squirrels occupy boreal, coniferous woods in northern Europe and Siberia, preferring [[Biology:Scots pine|Scots pine]], Norway spruce and Siberian pine. In western and southern Europe they are found in broad-leaved woods where the mixture of tree and shrub species provides a better year-round source of food. In most of the British Isles and in Italy, broad-leaved woodlands are now less suitable due to the better competitive feeding strategy of introduced grey squirrels.<ref>{{cite web|url=http://www.forestry.gov.uk/fr/INFD-8C8BHC|title=UK Red Squirrel Group – Red squirrel facts|website=Forestry.gov.uk|archive-url=https://web.archive.org/web/20170708092745/https://www.forestry.gov.uk/fr/INFD-8C8BHC|archive-date=8 July 2017|url-status=dead}}</ref>

==Ecology and behaviour==
[[File:The Great Walnut Disaster.webm|thumb|left|A red squirrel takes and loses a walnut]]
The red squirrel is found in both coniferous forest and temperate broadleaf woodlands. The squirrel makes a drey (nest) out of twigs in a branch-fork, forming a domed structure about 25 to 30&nbsp;cm in diameter. This is lined with [[Biology:Moss|moss]], leaves, grass and [[Biology:Bark (botany)|bark]]. Tree hollows and [[Biology:Woodpecker|woodpecker]] holes are also used. The red squirrel is a solitary animal and is shy and reluctant to share food with others. However, outside the breeding season and particularly in winter, several red squirrels may share a drey to keep warm. Social organization is based on dominance hierarchies within and between sexes; although males are not necessarily dominant to females, the dominant animals tend to be larger and older than subordinate animals, and dominant males tend to have larger home ranges than subordinate males or females.<ref name="wauters1992a">{{cite journal|author=Wauters, L.|author2=Swinnen, C.|author3=Dhondt, A. A.|name-list-style=amp |title=Activity budget and foraging behaviour or red squirrels (''Sciurus vulgaris'') in coniferous and deciduous habitats|doi=10.1111/j.1469-7998.1992.tb04345.x|year=1992|journal=Journal of Zoology|volume=227|pages=71–86}}</ref>

[[File:'Derek' (1).webm|thumb|right|A red squirrel eating]]
The red squirrel eats mostly the [[Biology:Seed|seed]]s of trees, neatly stripping conifer cones to get at the seeds within,<ref>Krauze-Gryz DAGNY, Gryz, JAKUB. 2015. A review of the diet of the red squirrel (''Sciurus vulgaris'') in different types of habitats. Red squirrels: ecology, conservation & management in Europe. European Squirrel Initiative, Stoneleigh Park, Warwickshire CV8 2LG, England, pp.39-50.</ref> [[Biology:Fungi|fungi]], nuts (especially [[Biology:Hazelnut|hazelnut]]s but also beech, chestnuts and acorns), [[Biology:Berry|berries]], vegetables, garden [[Biology:Flower|flower]]s, tree sap and young [[Biology:Shoot (botany)|shoot]]s.<ref name=r1>[http://www.forestry.gov.uk/forestry/Redsquirrel Forestry Commission – Red Squirrels] {{Webarchive|url=https://web.archive.org/web/20080228065329/http://www.forestry.gov.uk/forestry/Redsquirrel |date=28 February 2008 }}. Forestry.gov.uk. Retrieved on 25 July 2013.</ref>
More rarely, red squirrels may also eat bird eggs or nestlings. A Swedish study shows that out of 600 stomach contents of red squirrels examined, only 4 contained remnants of birds or eggs.<ref>{{cite web|title=Äter ekorrar fågelungar?|language=sv|website=Fråga en biolog|publisher=University of Lund|url=http://www1.biol.lu.se/fraga/?p=1103|archive-url=https://web.archive.org/web/20160304121434/http://www1.biol.lu.se/fraga/?p=1103|archive-date=4 March 2016|access-date=15 October 2015}}</ref>

[[File:'Belinda' (15262390078).webm|thumb|right|A red squirrel burying hazelnuts]]
[[File:European Red squirrel.jpg|thumb|Squirrel on a tree]]
Excess food is put into caches called "middens", either buried or in nooks or holes in trees, and eaten when food is scarce.<ref>{{Cite web|date=2020-08-21|title=Red Squirrel (Tamiasciurus hudsonicus)|url=https://www.nps.gov/jeca/red-squirrel-tamiasciurus-hudsonicus.htm}}</ref> Although the red squirrel remembers where it created caches at a better-than-chance level, its [[Physics:Spatial memory|spatial memory]] is substantially less accurate and durable than that of grey squirrels.<ref name="macdonald1997">{{cite journal |author=Macdonald, I. M. V. |s2cid=38573283|title=Field experiments on duration and precision of grey and red squirrel spatial memory |doi=10.1006/anbe.1996.0528 |year=1997 |journal=Animal Behaviour |volume=54|issue=4|pages=879–91|pmid=9344441}}</ref>
Between 60% and 80% of its active period may be spent foraging and feeding.<ref name="wauters1992b">{{cite journal|author1=Wauters, L.A.  |author2=Dhondt, A.A.  |s2cid=54357713 |name-list-style=amp |title=Spacing behaviour of red squirrels, ''Sciurus vulgaris'': variation between habitats and the sexes|doi=10.1016/S0003-3472(05)80225-8|year=1992|journal=Animal Behaviour|volume=43|issue=2|pages=297–311}}</ref> The active period for the red squirrel is in the morning and in the late afternoon and evening. It often rests in its nest in the middle of the day, avoiding the heat and the high visibility to [[Biology:Bird of prey|birds of prey]] that are dangers during these hours. During the winter, this mid-day rest is often much briefer, or absent entirely, although harsh weather may cause the animal to stay in its nest for days at a time.{{citation needed|date=October 2022}}

No territories are claimed between the red squirrels, and the feeding areas of individuals overlap considerably.{{citation needed|date=October 2022}}

===Reproduction===
[[File:Die vergleichende Osteologie (1821) Sciurus vulgaris.jpg|thumb|Skeleton of a squirrel]]
[[File:JJM SquirrelBaby 01.jpg|thumb|right|Two-week-old red squirrel]]
Mating can occur in late winter during February and March and in summer between June and July. Up to two litters a year per female are possible. Each litter averages three young, called kits.<ref>{{cite web|title=Red Squirrel Survival Trust: How do they breed?|url=https://www.rsst.org.uk/reds|access-date=6 November 2018}}</ref> Gestation is about 38 to 39 days. The young are looked after by the mother alone and are born helpless, blind, and deaf. They weigh between 10 and 15&nbsp; g. Their body is covered by hair at 21 days, their eyes and ears open after three to four weeks, and they develop all their teeth by 42 days. Juvenile red squirrels can eat solids around 40 days following birth and from that point can leave the nest on their own to find food; however, they still suckle from their mother until weaning occurs at 8 to 10 weeks.

During mating, males detect females that are in oestrus by an odour that they produce, and although there is no courtship, the male will chase the female for up to an hour prior to mating. Usually, several males will chase a single female until the dominant male, usually the largest in the group, mates with the female. Males and females will mate several times with many partners. Females must reach a minimum body mass before they enter oestrus, and heavy females on average produce more young. If food is scarce breeding may be delayed. Typically a female will produce her first litter in her second year.

===Life expectancy===  
[[File:Young-red-squirrel.jpg|thumb|right|Close up of a young red squirrel]]
Red squirrels that survive their first winter have a life expectancy of 3 years. Individuals may reach 7 years of age, and 10 in captivity. Survival is positively related to the availability of autumn-winter tree seeds; on average, 75–85% of juveniles die during their first winter, and mortality is approximately 50% for winters following the first.<ref name="gurnell1983">{{cite journal|author=Gurnell, J. |title=Squirrel numbers and the abundance of tree seeds |doi=10.1111/j.1365-2907.1983.tb00274.x |year=1983 |journal=Mammal Review|volume=13|issue=2–4|pages=133–148}}</ref>

==Enemies and threats==
Arboreal predators include small mammals such as the pine marten, [[Biology:Wildcat|wildcat]]s and the [[Biology:Stoat|stoat]], which preys on nestlings; birds, including [[Biology:Owl|owl]]s and raptors such as the [[Biology:Northern goshawk|goshawk]] and [[Biology:Buzzard|buzzard]]s, may also take the red squirrel. The [[Biology:Red fox|red fox]], cats and dogs can prey upon the red squirrel when it is on the ground. Humans influence the population size and mortality of the red squirrel by destroying or altering habitats, by causing road casualties, and by introducing non-native populations of the North American eastern grey squirrels.

The eastern grey squirrel and the red squirrel are not directly antagonistic, and violent conflict between these species is not a factor in the decline in red squirrel populations.<ref>{{cite web|url=http://rsst.org.uk/about-us/red-and-grey-squirrels/|title=Red and grey squirrels|work=Rsst}}</ref> However, the eastern grey squirrel appears to be able to decrease the red squirrel population due to several reasons:
*The eastern grey squirrel carries a disease, the squirrel parapoxvirus, that does not appear to affect their own health but will often kill the red squirrel. It was revealed in 2008 that the numbers of red squirrels at Formby (England) had declined by 80% as a result of this disease,<ref>{{Cite web|date=2008-09-28|title=Countryfile|url=https://www.bbc.co.uk/programmes/b00drmqm|website=BBC|quote=Charlotte Smith reports on why Britain's islands could be the last stronghold of the red squirrel.}}</ref> though the population is now recovering.<ref>[https://web.archive.org/web/20131205022902/http://www.nationaltrust.org.uk/article-1355813511001/ Formby's red squirrel population recovering], National trust, 25 November 2013</ref>
*The eastern grey squirrel can better digest [[Acorn|acorn]]s, while the red squirrel cannot access the proteins and fats in acorns as easily.<ref>{{cite web|url=http://rsst.org.uk/about-us/red-and-grey-squirrels/|title=Red and grey squirrels – RSST|website=rsst.org.uk|access-date=27 March 2018}}</ref>
*When the red squirrel is put under pressure, it will not breed as often.

In the UK, due to the above circumstances, the population has today fallen to 160,000 red squirrels or fewer (120,000 of these are in Scotland).<ref>{{cite web|title=Saving Scotland's Red Squirrels|url=http://scottishsquirrels.org.uk/|access-date=6 November 2018}}</ref> Outside the UK and Ireland, the impact of competition from the eastern grey squirrel has been observed in Piedmont, Italy, where two pairs escaped from captivity in 1948. A significant drop in red squirrel populations in the area has been observed since 1970, and it is feared that the eastern grey squirrel may expand into the rest of Europe.

==Conservation==
The red squirrel is protected in most of Europe, as it is listed in Appendix III of the Bern Convention; it is listed as being of least concern on the [[Organization:IUCN Red List|IUCN Red List]]. However, in some areas it is abundant and is hunted for its fur.

Although not thought to be under any threat worldwide, the red squirrel has nevertheless drastically reduced in number in the United Kingdom; especially after the grey squirrels were introduced from North America in the 1870s. Fewer than 140,000 individuals are thought to be left in 2013;<ref name=r1/> approximately 85% of which are in Scotland, with the Isle of Wight being the largest haven in England. A local charity, the Wight Squirrel Project,<ref>[http://www.wightsquirrels.co.uk/ The Wight Squirrel Project – Home]. Wightsquirrels.co.uk. Retrieved on 25 July 2013.</ref>  supports red squirrel conservation on the island, and islanders are actively recommended to report any invasive greys. The population decrease in Britain is often ascribed to the introduction of the eastern grey squirrel from North America,<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/england/7839653.stm|title=Black squirrels set to dominate|work=BBC News|date=20 January 2009|access-date=26 April 2009}}</ref> but the loss and fragmentation of its native woodland habitat has also played a significant role.

In contrast, the red squirrel may present a threat if introduced to regions outside its native range. It is classed as a "prohibited new organism" under New Zealand's Hazardous Substances and New Organisms Act 1996 preventing it from being imported into the country.<ref>{{cite web|url=http://legislation.govt.nz/act/public/1996/0030/latest/DLM386556.html#DLM386556|title=Hazardous Substances and New Organisms Act 2003 – Schedule 2 Prohibited new organisms|publisher=New Zealand Government|access-date=26 January 2012}}</ref>

===Projects===
[[File:Protecting the iconic red squirrel in Clocaenog forest.webm|thumb|Protecting the red squirrel in Clocaenog Forest, Wales]]
In January 1998, eradication of the non-native North American grey squirrel began on the North Wales island of Anglesey. This facilitated the natural recovery of the small remnant red squirrel population. It was followed by the successful reintroduction of the red squirrel into the pine stands of Newborough Forest.<ref>[http://www.redsquirrels.info/ Red squirrel conservation, squirrel ecology, and grey squirrel management]. Redsquirrels.info. Retrieved on 25 July 2013.</ref> Subsequent reintroductions into broadleaved woodland followed and today the island has the single largest red squirrel population in Wales. Brownsea Island in Poole Harbour is also populated exclusively by red rather than grey squirrels (approximately 200 individuals).

[[File:Sciurus vulgaris bearn 2001.jpg|thumb|With a brown coat]]
Mainland initiatives in southern Scotland and the north of England also rely upon grey squirrel control as the cornerstone of red squirrel conservation strategy. A local programme known as the "North East Scotland Biodiversity Partnership", an element of the national Biodiversity Action Plan was established in 1996.<ref>{{cite web|url=http://www.hutton.ac.uk/news/new-dawn-biodiversity-partnership-working|title=A new dawn for biodiversity partnership working|work=hutton.ac.uk}}</ref> This programme is administered by the Grampian Squirrel Society, with an aim of protecting the red squirrel; the programme centres on the Banchory and Cults areas. In 2008, the Scottish Wildlife Trust announced a four-year project which commenced in the spring of 2009 called "Saving Scotland's Red Squirrels".<ref>"A new era for Scotland's red squirrels?" in ''Scottish Wildlife'' (November 2008) No. 66. Edinburgh.</ref>

Other notable projects include red squirrel projects in the Greenfield Forest, including the buffer zones of Mallerstang, Garsdale and Widdale;<ref>[http://www.daelnet.co.uk/countrynews/country_news_29122008_2.cfm "Greenfield Forest declared England’s newest Red Squirrel Reserve"] {{Webarchive|url=https://web.archive.org/web/20110716031053/http://www.daelnet.co.uk/countrynews/country_news_29122008_2.cfm |date=16 July 2011 }} daelnet.co.uk. Retrieved 24 January 2011</ref> the Northumberland Kielder Forest Project; and within the National Trust reserve in Formby. These projects were originally part of the Save Our Squirrels campaign that aimed to protect red squirrels in the north of England, but now form part of a five-year Government-led partnership conservation project called "Red Squirrels Northern England"<ref>[http://www.rsne.org.uk/ Red Squirrels Northern England]. Rsne.org.uk. Retrieved on 25 July 2013.</ref> to undertake grey squirrel control in areas important for red squirrels.

On the Isle of Wight, local volunteers are encouraged to record data on the existing red squirrel population, and to monitor it for the presence of invasive greys; as the red squirrel is still dominant on the island, these volunteers are also requested to cull any greys they find.<ref>{{Cite web|date=2017-02-27|title=Volunteers being sought to kill invasive grey squirrels|url=https://onthewight.com/volunteers-being-sought-to-kill-invasive-grey-squirrels/|access-date=2021-07-21|website=Isle of Wight News from OnTheWight|language=en-GB}}</ref> In order to protect existing populations, increasing amounts of legislation have been issued to prevent the further release and expansion of grey squirrel populations. Under the Wildlife and Countryside Act 1981, it is an offense to release captured grey squirrels, indicating that any captured individuals must be culled.<ref>{{Cite web|title=Grey squirrel control|url=https://basc.org.uk/advice/basc-grey-squirrel-control/|access-date=2021-07-21|website=The British Association for Shooting and Conservation|language=en-GB}}</ref><ref>{{Cite web|title=Pest control on your property|url=https://www.gov.uk/pest-control-on-your-property|access-date=2021-07-21|website=GOV.UK|language=en}}</ref> Additional rules covered under the WCA's Schedules 5 and 6 include limitations on the keeping of red squirrels in captivity, and also prohibits the culling of red squirrels.<ref>{{Cite web|title=Squirrels and the law|url=https://midwalesredsquirrels.org/advice/squirrels-and-the-law/|access-date=2021-07-21|website=Red Squirrel Partnership {{!}} Partneriaeth Gwiwerod Coch|language=en-US}}</ref>

Research undertaken in 2007 in the UK credits the pine marten with reducing the population of the invasive eastern grey squirrel. Where the range of the expanding pine marten population meets that of the eastern grey squirrel, the population of these squirrels retreats. It is theorised that, because the grey squirrel spends more time on the ground than the red, they are far more likely to come in contact with this predator.<ref>Watson, Jeremy (30 December 2007) [http://www.scotsman.com/news/environment/tufty-s-saviour-to-the-rescue-1-1430388 "Tufty's saviour to the rescue"]. ''Scotland on Sunday''. Edinburgh.</ref>

During October 2012, four male and one female red squirrel, on permanent loan from the British Wildlife Centre, were transported to Tresco in the Isles of Scilly by helicopter, and released into Abbey Wood, near the Abbey Gardens. Only two survived and a further 20 were transported and released in October 2013.<ref>[http://www.scillytoday.com/2013/06/18/trescos-red-squirrel-colony-to-be-restocked/ Tresco’s Red Squirrel Colony To Be Restocked]. Scilly Today (18 June 2013). Retrieved on 25 July 2013.</ref> Although the red squirrel is not indigenous to the Isles of Scilly, those who supported this work intend to use Tresco as a "safe haven" for the endangered mammal, as the islands are free of predators such as [[Biology:Red fox|foxes]], and of the squirrel pox-carrying grey squirrel.<ref>{{cite news|last=Mumford|first=Clive|title=Squirrels to be released in 2013|url=http://www.thisiscornwall.co.uk/Squirrels-set-released-2013/story-17210756-detail/story.html|archive-url=https://archive.today/2013.05.05-130103/http://www.thisiscornwall.co.uk/Squirrels-set-released-2013/story-17210756-detail/story.html|url-status=dead|archive-date=5 May 2013|access-date=14 November 2012|newspaper=The Cornishman|date=1 November 2012|page=16}}</ref><ref>{{cite news|title=RNAS Culdrose helicopter flies red squirrels to Tresco|url=https://www.bbc.co.uk/news/uk-england-cornwall-24164247|publisher=BBC|access-date=5 November 2013|work=BBC News|date=20 September 2013}}</ref>

==Historical, cultural and financial significance==
[[File:Kauniainen.vaakuna.svg|thumb|upright|A red squirrel in the coat of arms of Kauniainen, a town in Finland]]
[[File:Squirrel Eating.jpg|thumb|upright|"Squirrel" illustration from "British Mammals" by A. Thorburn, 1920]]

Squirrel Nutkin is a character, always illustrated as a red squirrel, in English author Beatrix Potter's books for children.

"Ekorr'n satt i granen" (The Squirrel sat in the fir tree) is a well-known and appreciated children's song in Sweden. Text and lyrics by Alice Tegnér in 1892.

Charles Dennim, protagonist of Geoffrey Household's novel ''Watcher in the Shadows,'' is a zoologist who studies and writes about red squirrels.

In Norse mythology, Ratatoskr is a red squirrel who runs up and down with messages in the world tree, Yggdrasil, and spreads gossip. In particular, he carried messages between the unnamed eagle at the top of Yggdrasill and the wyrm Níðhöggr beneath its roots.

The red squirrel used to be widely hunted for its pelt. In Finland, squirrel pelts were used as currency in ancient times, before the introduction of coinage.<ref>[http://www.holappa.info/html/verot/oravannahat.html Verot 1500–1600 luvulla:Oravannahat] {{webarchive|url=https://web.archive.org/web/20130624170139/http://www.holappa.info/html/verot/oravannahat.html |date=24 June 2013 }}. Holappa.info. Retrieved on 25 July 2013.</ref> The expression "squirrel pelt" is still widely understood there to be a reference to money.  It has been suggested that the trade in red squirrel fur, highly prized in the medieval period and intensively traded, may have been responsible for the [[Medicine:Leprosy|leprosy]] epidemic in medieval Europe. Within Great Britain, widespread leprosy is found early in East Anglia, to which many of the squirrel furs were traded, and the strain is the same as that found in modern red squirrels on Brownsea Island.<ref>{{cite journal |last1=Inskip |first1=S |last2=Taylor |first2=GM |last3=Anderson |first3=S |last4=Stewart |first4=G |s2cid=33997231 |title=Leprosy in pre-Norman Suffolk, UK: biomolecular and geochemical analysis of the woman from Hoxne. |journal=Journal of Medical Microbiology |date=November 2017 |volume=66 |issue=11 |pages=1640–1649 |doi=10.1099/jmm.0.000606 |pmid=28984227|url=http://epubs.surrey.ac.uk/846050/1/Inskip%20et%20al%20submission%20proof%20%28002%29.pdf }}</ref><ref>{{cite web |title=Could squirrel fur trade have contributed to England's medieval leprosy outbreak? |url=https://www.sciencedaily.com/releases/2017/10/171025103109.htm |website=ScienceDaily |access-date=21 November 2018 |date=25 October 2017}}</ref>

The red squirrel is the national mammal of Denmark.<ref name=naturDK>{{cite web |url=https://naturstyrelsen.dk/om-os/kontakt/faq/nationalplanter-og-dyr/ |title=Nationalplanter og -dyr | publisher=Naturstyrelsen, Danish Ministry of the Environment |access-date=28 December 2019 | language=da | trans-title=Nationalplants and -animals }}</ref>

Red squirrels are a common feature in English heraldry, where they are always depicted sitting up and often in the act of cracking a nut.<ref name="Davies">{{cite book|url=https://archive.org/details/completeguidetoh00foxduoft|author=Fox-Davies, Arthur |title=A Complete Guide to Heraldry|publisher= T.C. and E.C. Jack|place= London|year= 1909|page= 214}}</ref>

==Taxonomy==
[[File:Red squirrel subspecies.png|thumb|upright|Various red squirrel subspecies; A) ''S. v. vulgaris'' from Sweden, B) ''S. v. fuscoater'' from Germany, C) ''S. v. infuscatus'' from central Spain]]
[[File:A squirrel in South Korea.jpg|thumb|upright|''S. v. mantchuricus'' from South Korea]]

There have been over 40 described [[Biology:Subspecies|subspecies]] of the red squirrel, but the taxonomic status of some of these is uncertain. A study published in 1971 recognises 16 subspecies and has served as a basis for subsequent taxonomic work.<ref name="sidorowicz1971">{{cite journal|author=Sidorowicz, J.|year=1971|title= Problems of subspecific taxonomy of squirrel (''Sciurus vulgaris'' L.) in Palaearctic|journal=Zoologischer Anzeiger|volume=187|pages=123–142}}</ref><ref name="lurz2005">{{cite journal|author1=Lurz, P.W.W. |author2=Gurnell, John |author3=Magris, Louise  |name-list-style=amp |year=2005|title= ''Sciurus vulgaris''|journal=Mammalian Species|volume= 769|pages=1–10|url=http://www.science.smith.edu/msi/pdf/769_Sciurus_vulgaris.pdf|doi=10.1644/1545-1410(2005)769[0001:SV]2.0.CO;2|s2cid=33479534 }}</ref> Although the validity of some subspecies is labelled with uncertainty because of the large variation in red squirrels even within a single region,<ref name="lurz2005"/> others are relatively distinctive and one of these, ''S. v. meridionalis'' of South Italy, was elevated to species status as the [[Biology:Calabrian black squirrel|Calabrian black squirrel]] in 2017.<ref>{{cite journal | author1=Wauters, Lucas A. | author2=Giovanni Amori | author3=Gaetano Aloise | author4=Spartaco Gippoliti | author5=Paolo Agnelli | author6=Andrea Galimberti | author7=Maurizio Casiraghi | author8=Damiano Preatoni | author9=Adriano Martinoli | year=2017 | title=New endemic mammal species for Europe: ''Sciurus meridionalis'' (Rodentia, Sciuridae) | journal=Hystrix | volume=28 | number=1 | pages=1–28 | doi=10.4404/hystrix-28.1-12015}}</ref> At present, there are 23 recognized subspecies of the red squirrel.<ref name="Thorington"/> Genetic studies indicate that another, ''S. v. hoffmanni'' of Sierra Espuña in southeast Spain (below included in ''S. v. alpinus''), deserves recognition as distinct.<ref>{{cite journal | author1=Rocha, Rita Gomes | author2=Lucas A. Wauters | author3=Maria da Luz Mathias | author4=Carlos Fonseca | year=2014 | title=Will an ancient refuge become a modern one? A critical review on the conservation and research priorities for the red squirrel (''Sciurus vulgaris'') in the Iberian peninsula | journal=Hystrix | volume=25 | number=1 | pages=9–13 | doi=10.4404/hystrix-25.1-9496}}</ref>

*''S. v. alpinus''. Desmarest, 1822. (synonyms: ''S. v. baeticus'', ''hoffmanni'', ''infuscatus'', ''italicus'', ''numantius'' and ''segurae'')
*''S. v. altaicus''. Serebrennikov, 1928.
*''S. v. anadyrensis''. Ognev, 1929.
*''S. v. arcticus''. Trouessart, 1906. (synonym: ''S. v. jacutensis'')
*''S. v. balcanicus''. Heinrich, 1936. (synonyms: ''S. v. istrandjae'' and ''rhodopensis'')
*''S. v. chiliensis''. Sowerby, 1921.
*''S. v. cinerea''. Hermann, 1804.
*''S. v. dulkeiti''. Ognev, 1929.
*''S. v. exalbidus''. Pallas, 1778. (synonyms: ''S. v. argenteus'' and ''kalbinensis'')
*''S. v. fedjushini''. Ognev, 1935.
*''S. v. formosovi''. Ognev, 1935.
*''S. v. fuscoater''. Altum, 1876. (synonyms: ''S. v. brunnea'', ''gotthardi'', ''graeca'', ''nigrescens'', ''russus'' and ''rutilans'')
*''S. v. fusconigricans''. Dvigubsky, 1804
*''S. v. leucourus''. Kerr, 1792.
*''S. v. lilaeus''. Miller, 1907. (synonyms: ''S. v. ameliae'' and ''croaticus'')
*''S. v. mantchuricus''. Thomas, 1909. (synonyms: ''S. v. coreae'' and ''coreanus'')
*''S. v. martensi''. Matschie, 1901. (synonym: ''S. v. jenissejensis'')
*''S. v. ognevi''. Migulin, 1928. (synonyms: ''S. v. bashkiricus'', ''golzmajeri'' and ''uralensis'')
*''S. v. orientis''. Thomas, 1906. Ezo Red Squirrel (Hokkaidō).
*''S. v. rupestris''. Thomas, 1907
*''S. v. ukrainicus''. Migulin, 1928. (synonym: ''S. v. kessleri'')
*''S. v. varius''. [[Biography:Johann Friedrich Gmelin|Gmelin]], 1789.
*''S. v. vulgaris''. [[Biography:Carl Linnaeus|Linnaeus]], [[Biology:10th edition of Systema Naturae|1758]].<ref name="Linn1758">{{cite book|last=Linnaeus |first=Carolus |title=Systema naturae per regna tria naturae :secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. |publisher=Holmiae (Laurentii Salvii) |year=1758 |url=https://www.biodiversitylibrary.org/bibliography/542 |access-date=8 March 2010 |language=la |edition=10th}}</ref> (synonyms: ''S. v. albonotatus'', ''albus'', ''carpathicus'', ''europaeus'', ''niger'', ''rufus'' and ''typicus'')

==References==
{{Reflist|30em}}

==External links==
{{Commons and category|Sciurus vulgaris|Sciurus vulgaris}}
*[https://web.archive.org/web/20080509145518/http://www.arkive.org/species/ARK/mammals/Sciurus_vulgaris/ ARKive]: photographs and videos
*[http://scottishsquirrels.org.uk/ A partnership to save the red squirrel, between the Scottish Wildlife Trust, et al.]
*[http://www.wildlifeonline.me.uk/squirrels.html WildlifeOnline: Natural History of Tree Squirrels]
*[https://web.archive.org/web/20101226033234/http://news.scotsman.com/nature/Red-squirrels-make-a-comeback.6078169.jp Red squirrels make a comeback as culling of grey rivals brings results]
*[https://dx.doi.org/10.7589/0090-3558-48.2.454 Acute Fatal Toxoplasmosis in Three Eurasian Red Squirrels]
{{Taxonbar|from=Q4388}}

[[Category:Sciurus]]

{{Sourceattribution|Red squirrel}}