The Red squirrel is an iconic part of Britain’s fauna and a popular species for wildlife watchers and photographers alike. This mammal has a long and somewhat juxtaposed history in the UK. Long considered a pest to forestry and actively exterminated from many plantations during the 18th and 19th centuries by “squirrel destruction clubs”, the Red squirrel took the lead role in one of Beatrix Potter’s acclaimed series of children’s books. The Tale of Squirrel Nutkin, published in August 1903, follows the exploits of “Nutkin” as he presses his luck with the Old Brown owl and was inspired by Potter’s summer holiday watching squirrels at the Lingholm estate in the Lake District in 1901.
Today, although Red squirrels enjoy a wide distribution across Europe and into Asia, their populations are suffering substantial declines in Britain such that, outside of Scotland and Ireland, only largely fragmented populations can be found in England and Wales. Many factors appear to have contributed to this decline, although the introduction of the Grey squirrel by Victorian collectors is seen as perhaps the most significant. The tireless work of conservationists is trying to tackle the decline with the aim of allowing Reds to expand their range.
The Red squirrel at a glance
Size: Max. length about 45cm (18 in.), of which up to 20cm (8 in.) may be tail. Commonly, ~ 21cm (8in.) inc. tail.
Colour: Highly variable; range from black to dull yellowy-brown (“buff”), covering most shades of red and brown. Albinos rare; melanistic (black) common in some regions (e.g. continental Europe), rare in UK.
Distribution: Throughout Europe and Asia, from ~70oN to 30oN; Britain and China represent limits of range. Within UK, still reasonably widespread through northern England, southern and eastern Scotland, and much (excl. far west) of Ireland. Also found in isolated pockets of England (e.g. Brownsea Island and Isle of Wight) and three distinct populations in Wales.
Longevity: Max. (captivity) is 10 years. In wild, average is 3 yrs; max. in wild probably 7 yrs.
Sexing: Impossible at distance; during breeding season close inspection reveals swollen, darkly stained testes. Distance between genital openings can be used to sex squirrels during handling.
Activity: Diurnal (daytime) species, emerging ~30 min. after sunrise. Bimodal activity periods during the summer (morning and evening) and unimodal in winter (morning).
Dens: Referred to as “dreys”; usually in trees (occasionally on ground). Composed of leaves and twigs; lined with moss. Roughly spherical and typically 30cm (1ft.) diameter. Nursing females may have several dreys in area to facilitate moving young when threatened.
Territory: Range over ave. 70 ha (range 20-100 ha; up to 247 ac.); have “core areas” of intense use and these areas will be defended against intruders. Territory establishment essential for successful reproduction. Territory quality directly impacts fecundity.
Diet: Primarily seeds and plant matter, incl. berries and fruit. Opportunists; diet includes fungi, nuts, seeds, bark, sap, soil (minerals?), roots, cereals, insects (incidental?), bird chicks and eggs.
Reproduction: Females polyoestrus with bimodal peaks: winter (Dec.-Mar.) mating produces young in spring (Mar.-May); spring mating yields young during summer (July-Sept.). Gestation 36 to 42 days (depending on weather and food). Ave. litter is 3 young (kittens). Young outside at 7 wks; fully weaned by 10 wks and independent at 12 to 16 wks. Sexually mature at 6 months old. Breeding heavily influenced by mast crop and may skip breeding seasons following poor autumn.
Behaviour & Sociality: Primarily solitary; drey sharing known, individuals seem familiar with each other. Hierarchy system known between and within sexes; males not necessarily dominant to females. Peak dispersal in autumn (some in summer and spring). Spend less time on ground than Greys. Emit various acoustically distinct calls; foot stomping, tail flicking and chasing my accompany agonistic calls. During breeding season, single female may be pursued by several males. Chasing, chattering and tail-flicking often witnessed during mating chases. Kittens engage in solitary object-play and social play, including chasing; occasionally solitary play persists in adults, although apparently less common than in Greys, and includes erratic rolling and jumping.
Threats: Large numbers killed on roads and by viruses (such as squirrelpox). Habitat loss, encroachment by Greys and changes to habitat management also implicated in species decline. Historically persecuted as pest to forestry. Globally, predators include foxes, wildcats, martens, goshawks, raptors (esp. buzzards), stoats, coyotes, snakes and bobcats.
Belinda, The Forest How Red Squirrel - by Peter Trimming
The Book Guild -- 2016 -- ISBN: 978-1910878552
Highland Deer Forest - by Lea MacNally
J.M. Dent & Sons Ltd. -- 1970 -- ISBN: 978-0330234665
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Irish Naturalists' Journal -- 2008
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New Holland Publishers -- 2003 -- ISBN: 978-1845171131
Red Squirrels - by Helen Butler
Wight Squirrel Project -- 1998 -- ISBN: 978-0955231438
Red Squirrels: Ecology, Conservation & Management in Europe - by Craig Shuttleworth, Peter Lurz & Matthew Hayward
European Squirrel Initiative -- 2015 -- ISBN: 978-0954757618
Silent Fields: The long decline of a nation’s wildlife - by Roger Lovegrove
Oxford Univesrity Press -- 2007 -- ISBN: 978-0199548156
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BBC Books -- 1994 -- ISBN: 978-0563364962
Squirrels - by Monica Shorten
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Squirrels - by Jessica Holm
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Isabelline Films -- 2015 -- ISBN: N/A
The Conservation of Red Squirrels - by John Gurnell & Peter Lurz (eds)
PTES -- 1997 -- ISBN: 978-1855800144
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Brown Reference Group -- 2006 -- ISBN: 978-0199206087
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Christopher Helm Publishers -- 1987 -- ISBN: 978-0747012108
The Red Squirrel - by Jessica Holm
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The Red Squirrel: Redressing the Wrong - by Charles Dutton
European Squirrel Initiative -- 2004 -- ISBN: N/A
The Wildlife Trust’s Handbook of Garden Wildlife - by Nicholas Hammond
Bloombury -- 2014 -- ISBN: 978-1472915863
UK Mammals: Species Status & Population Trends - by The Tracking Mammals Partnership
JNCC/TMP -- 2005 -- ISBN: 978-1861075680
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Urban Wildlife - by Peter Shirley
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Wild Animals of Britain & Europe - by Helga Hofmann
Collins -- 1995 -- ISBN: 978-0007627271