Glaucomys sabrinus
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
Glaucomys
Glaucomys sabrinus

description: 111. Northern Flying Squirrel <i>Glaucomys sabrinus</i> <b>French:</b> Grand Polatouche / <b>German:</b> Nordliches Gleithornchen / <b>Spanish:</b> Ardilla voladora septentrional Other common names: Carolina Flying Squirrel; Alaska Coast Flying Squirrel (zaphaeus), Atnarko Flying Squirrel (reductus), Bachman Flying Squirrel (oregonensis), Bangs Flying Squirrel (bangsi), Broad-footed Flying Squirrel (/atipes), California Coast Flying Squirrel (stephens), Cascade Flying Squirrel (fuliginosus), Hudson Bay Flying Squirrel (sabrinus), Klamath Flying Squirrel (klamathensis), Labrador Flying Squirrel (makkovikensis), Mearns's Flying Squirrel (macrotis), Okanagan Flying Squirrel (columbiensis), Richardson Flying Squirrel (alpinus), San Bernardino Flying Squirrel (californicus), Sierra Flying Squirrel (lascivus), Yellow-bellied Flying Squirrel (flaviventris), Yukon Flying Squirrel (yukonensis) <b>Taxonomy.</b> Sciurus sabrinus Shaw, 1801, no type locality given. Restricted by A. H. Howell in 1918 to the mouth of the Severn River, Ontario, Canada. Twenty-five subspecies are recognized. <b>Subspecies and Distribution.</b> G.s.sabrinusShaw,1801—EQuebecandWLabradortoNOntariototheNWportionoftheNorthwestTerritories(Canada)toNMinnesotatoNWWisconsin(USA)andSOntarioandSQuebec(Canada). G.s.alpinusRichardson,1828—N&amp;EBritishColumbia,extendingslightlyovertheNborderintotheYukonandovertheEborderintoSWAlberta(Canada). G.s.bangsiRhoads,1897—CIdaho,EOregon,SWMontana,SouthDakota,andWyo-mingMts(USA). G.s.californicusRhoads,1897—SanBernardinoandSanJacintoMtsinSWCalifornia(USA). G.s.canescensA.H.Howell,1915—NENorthDakota,extendingintoMinnesota(USA)andManitoba(Canada). G.s.coloratusHandley,1953—theborderareaofNorthCarolinaandTennessee(USA). G.s.columbiensisA.H.Howell,1915—S&amp;CBritishColumbia(Canada)andNWash-ington(USA). G.s.flaviventrisA.H.Howell,1915—NCalifornia(USA)fromtheTrinityMtsinSiski-youandTrinitycountiesEtotheWarnerMtsinModocCounty. G.s.fuliginosusRhoads,1897—theCascadeRange,fromSBritishColumbia(Canada)throughWashingtonandOregontotheSiskiyouMts,California(USA). G.s.fuscusMiller,1936—E&amp;CWestVirginia(USA). G.s.goodwiniR.M.Anderson,1943—theQuebecPeninsulatoNNewBrunswick(Canada). G.s.gouldiR.M.Anderson,1943—PrinceEdwardIandNovaScotia(Canada). G.s.griseifronsA.H.Howell,1934—LakeBay,onPrinceofWalesI,Alaska(USA). G.s.klamathensisMerriam,1897—COregon,EoftheCascadeRange(USA). G.s.lascivusBangs,1899—SierraNevadaRangeandNtoEShastaCounty,California(USA). G.s.latipesA.H.Howell,1915—SEBritishColumbiaandAlberta(Canada),andhigh-erMtsofNIdahoandNWMontana,andWashington(USA). G.s.lucifugusHall,1934—Utah(USA). G.s.macrotisMearns,1898—SOntariotoNewBrunswick(Canada)toMaine,StoNPennsylvania,andWtoNMichigan,NEWisconsintoElkRiver,Minnesota(USA). G.s.makkovikensisSornborger,1900—NENewfoundlandandLabradorandadjacentQuebec(Canada). G.s.murinauralisMusser,1961—MtsofSWUtah(USA). G.s.oregonensisBachman,1839—coastalregionsofSBritishColumbia(Canada),WashingtonandOregon(USA). G.s.reductusCowan,1937—mid-coastalareaofBritishColumbia,neartheKoeyeRiver,andinlandtowardWisteriaandChezacut,theChilotanPlateau(Canada). G.s.stephensiMerriam,1900—NWcoastalCalifornia(USA). G.s.yukonensisOsgood,1900—S&amp;CYukon(Canada),andS&amp;CAlaska(USA). G. s. zaphaeus Osgood, 1905 — coastal region of SE Alaska (USA) and N British Columbia (Canada). <b>Descriptive notes.</b> Head—body 115-190 mm, tail 122-160 mm; weight 110-185 g. Nominate sabrinus is vinaceous cinnamon on upper parts; sides of head are smoke gray; eye ring and dorsal surface oftail are fuscous; ventral surface oftail is shaded with brown; and underparts are soiled white, washed with pale yellowish and drab shaded. Subspecies alpinus is grayer and less vinaceous above; tail is darker, wood-brown mixed with fuscous on dorsal and ventral surfaces. Subspecies bangs: has more drab upper parts, grayerfeet, and pinkish cinnamon underparts. Subspecies californicus is paler and grayer than lascivus and has grayish wash on front offace, upper parts are light drab to yellowish wood-brown, and underparts are soiled buffy white-washed. Subspecies canescens is palest of subspecies; it resembles subspecies macrotis but has grayer head; upper parts and feet are pale; and underparts are whiter than on sabrinus. Subspecies coloratus has dorsum between cinnamon-brown and mikado brown; underparts are pale yellow-orange to ocherous buff; underside oftail is suffused with orange, with tail sooty along edges of distal one-half and at tip; and sides of face are gray washed with buff. Upper parts of columbiensis are vinaceous cinnamon to vinaceous fawn;it is paler above and below than oregonensis. Subspecies flaviventris is smaller than klamathensis, with more yellow on feet and underparts, which are white-washed with pale greenish yellow merging into woodbrown along sides. Subspecies fuliginosus resembles columbiensis but is browner above, darker below, and less brown on tail; it is also less rufous than oregonensis. Subspecies JSuscus is smaller and darker, with clear gray cheeks. Subspecies goodwini has a sayal brown to hazel back; underparts are light pinkish cinnamon, and feet are dark fuscous; and itis grayer on face and cheeks than gould:, with darker and duller winter coat and paler than makkovikensis. Tail of goodwiniis smoke gray and slightly darker brown toward tip, with underside oftail smoke gray to dull cinnamon-buff. Dorsum of gould: is buffy brown to dull orange-cinnamon; underparts are white, with hairs slightly buffy at tips; dorsal surface of tail is dull cinnamon, and ventralside is pinkish buff; feet are pale fuscous; and coat is brighter andtail is paler (above and below) than on macrotis and goodwini. Subspecies griseifrons is similar to zaphaeus, but upper parts of griseifrons are slightly darker, including tail, hindfeet, and gliding membrane; underparts are more whitish and less bufty; and sides of head and neck are more extensively grayish. Subspecies klamathensis resembles Juliginosus but is grayer on upper parts. Subspecies lascivus is similar to flaviventris but smaller and without yellow suffusion on underparts, which are instead grayish white with faint wash of light pink-cinnamon. Subspecies latipes is relatively large; it is similar to Suliginosus, although latipes is darker and grayer, and upper parts are drab, mixed with brown. Subspecies lucifugus is most similar to bangs, but lucifugus is paler, with less red and grayer, especially on face; feet are drabber; and underparts are whitish, lacking pinkish cinnamon tone. Subspecies macrotis tends to be on the smaller side; ears are slightly longer than typical; upper parts and hindfeet are pale cinnamon; and underparts are white with irregular washes of light pinkish cinnamon. Subspecies makkovikensisis slightly larger than typical; it has darker upper parts and feet and darker face and tail. Subspecies murinauralis resembles lucifugus but has upper parts that are more yellowish orange; head, face, and hindfeet of murinauralis are grayer; dorsal surface oftail is uniformly gray, without rufous tone, and darker on apical one-third oftail. Subspecies oregonensis is redder than zaphaeus, with upper parts dark reddish brown and underparts cinnamon or buff. Subspecies reductus is paler, less red on dorsal surface, and whiter on ventral surface; it has clear gray cheeks. Subspecies stephensi has reddish upper parts that are intermediate between lascivus and oregonensis, more precisely, upper parts are wood-brown, and underparts are whitish, with irregular washes oflight pinkish cinnamon. Subspecies yukonensis is larger than nominate sabrinus, with longertail and broader hindfoot; upper parts are cinnamon, pinkish to vinaceous. Subspecies zaphaeus resembles alpinus but has browner upper parts and darker underparts; eye ring is blackish. Chromosomal complement is 2n = 48 and FN = 74. Karyotype consists of 14 pairs of biarmed autosomes and nine pairs of acrocentric autosomes. Sex chromosomes consist of medium submetacentric X-chromosome and small submetacentric Y-chromosome. Individual chromosome length differs from that of the Southern Flying Squirrel (Glaucomys volans). <b>Habitat.</b> Variety of forest types but most often boreal conifer forests or mixed stands, with significant conifer component. Although previously considered a specialist of primary forests, there is increasing evidence that the Northern Flying Squirrelis a habitat generalist. In the Appalachian Mountains (from New York to north-western Georgia, USA), it is often associated with spruce (Picea), fir (Abies), and hemlock (Tsuga), all Pinaceae; it also occurs in mature deciduousforests of yellow birch (Betula alleghaniensis, Betulaceae), sugar maple (Acer saccharum, Sapindaceae), beech (Fagus), and oak (Quercus), both Fagaceae. <b>Food and Feeding.</b> Although the Northern Flying Squirrel eats seeds and nuts of conifers and hardwoods,it is considered less granivorous than the Southern Flying Squirrel and may be an obligate mycophagist in many parts ofits distribution, often consuming large quantities of hypogeous fungi at certain times ofthe year. It may serve a keystone role by dispersing fungal spores and inoculating tree roots. The Northern Flying Squirrel also eats tree buds, catkins, staminate cones, tree sap, wild fruits, and animal material (e.g. songbirds, bird eggs, and insects). <b>Breeding.</b> Gestation of the Northern Flying Squirrel lasts 37-42 days; litters are 1-6 young but usually 2-4 young. Although three litters per year have been reported,it is unlikely that the same female produces more than one litter annually. Young are 5-6 g at birth. <b>Activity patterns.</b> The Northern Flying Squirrel is generally nocturnal, but it is also active either shortly before or after dawn and immediately after sunset. It is active throughout winter and often nests with conspecifics to conserve energy; it does not appear to have the same physiological adaptations for dealing with extreme cold as the Southern Flying Squirrel. <b>Movements, Home range and Social organization.</b> The Northern Flying Squirrel moves terrestrially and by gliding short distances, usually less than 20 m. Vocalizations are common when conspecifics interact or when disturbed, but details on context and function of vocalizations are not available. The Northern Flying Squirrel builds nests in cavities but also constructs dreys with twigs, bark, moss, lichens, and roots. Cavities are preferred in colder climates. Nests are lined with finely shredded material to provide insulation, typically allowing occupied nests to be maintained above 27°C, even when outside temperatures are as low as 4°C. Densities average 0-25-2-5 ind/ha but can as high as 12 ind/ ha. In the Oregon Cascades, USA, density is ¢.2 ind/ha in secondary and primary Douglas fir (Pseudotsuga menziesii, Pinaceae) stands. Home ranges are 1-7 ha but can reach 35 ha in the eastern part of the distribution. Supplementation experiments show thatin the Pacific Northwest, food (but not nest cavities) limits densities. The Northern Flying Squirrel may be excluded from nest cavities where it is sympatric with the Southern Flying Squirrel. In Pennsylvania, USA, the two species converge on stands of hemlock for nesting, and they have even been observed nesting together. Here, the Southern Flying Squirrel spends most ofits time foraging in adjacent hardwoods, but the Northern Flying Squirrelrestricts nearly all of its activity to hemlocks. Non-overlapping distributions of the Northern Flying Squirrel and the Southern Flying Squirrel may result from parasite-mediated competitive exclusion where the nematode Strongyloides robustus, a common parasite of the Southern Flying Squirrel,is potentially lethal to the Northern Flying Squirrel. Fossils of the Northern Flying Squirrel have been reported from the late Pleistocene. Cytochrome-b sequence data are significantly more variable in the Northern Flying Squirrel than in the Southern Flying Squirrel, and it shows two separate lineagesin Northern Flying Squirrel, suggesting the possibility of a third species of Glaucomys. Loss of genetic variation and genetic differentiation are evident in populations on coastal islands in the Pacific Northwest. Despite previous evidence of differences in chromosome number and bacular structure, the two species of Glaucomys have been reported to hybridize, producing viable offspring that are intermediate in pelage characteristics and size. Such hybridization in the north-eastern part of the distribution may be due to climate change, habitat loss, or a combination of the two, which has increased sympatry between the two species. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. Current population trend of the Northern Flying Squirrelis stable. Subspecies fuscus and coloratus in the Appalachian Mountains are listed as endangered in the USA. Declines in the Appalachians may be due to a roundworm parasite (Strongiloides robustus) of Southern Flying Squirrels that is fatal or debilitating to Northern Flying Squirrels. Habitat changes that limit connectivity are detrimental because the Northern Flying Squirrel is unwilling to travel on the ground and its glide distanceis limited. <b>Bibliography.</b> Anthony (1928), Arbogast (1999), Arbogast et al. (2005), Bakker &amp; Hastings (2002), Bidlack &amp; Cook (2001), Bradley &amp; Marzluff (2003), Carey (2000, 2001, 2002), Carey, Horton &amp; Biswell (1992), Carey, Kershner et al. (1999), Demboski et al. (1998), Garroway et al. (2010), Hackett &amp; Pagels (2003), Hall (1991), Holloway &amp; Malcolm (2007), Howell (1915a, 1918), Jackson (2012), Jackson &amp; Thorington (2012), Krichbaum et al. (2010), Linzey &amp; NatureServe (Hammerson) (2008w), Loeb et al. (2000), Meyeret al. (2005), Mitchell (2001), Odom et al. (2001), Payne et al. (1989), Perez-Orella &amp; Schulte-Hostedde (2005), Pyare &amp; Longland (2001), Ransome &amp; Sullivan (1997, 2002, 2003, 2004), Raphael (1984), Rosenberg &amp; Anthony (1992), Scheibe et al. (2007), Smith W. P (2007), Smith, W. P. et al. (2004), Thorington et al. (2012), Vernes (2001), Vernes et al. (2004), Weig| (2007), Wells-Gosling &amp; Heaney (1984), Witt (1991, 1992), Zittlau et al. (2000).
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 pages 759-760, DOI: 10.5281/zenodo.6840226