Western Capercaillie Tetrao urogallus Scientific name definitions

80–115 cm, female much smaller, 59–64 cm (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ); male 3300–4300 g (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) (up to 6500 g), female 1440–2500 g (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Large, very dark grouse, mostly slate-grey with fine vermiculations, blackish on head and neck; breast glossy greenish black; wings dark brown; white carpal patch, and variable amount of white on upper and undertail-coverts and underparts; tail long and rounded (18, sometimes 24 rectrices) (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ); bill ivory white; combs scarlet. Female barred and mottled black , grey and buff; larger than that of Lyrurus tetrix, with longer, more rounded rufous tail , and a large rusty patch on breast . First-winter male similar to adult but smaller, with narrower tail feathers and smaller and dusk­ier bill; in both sexes first-winter has outer two primaries speckled reddish brown. Juvenile plumage (short-lived) (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) shows pale buff shaft-streaks on mantle, shorter and duller rufous tail with buff tip, and female is more coarsely barred with black than same-age male, which has grey wash to uppertail-coverts (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Races separated mainly on darkness of plumage and size, but there is extensive individual and clinal variation, e.g. in extent and saturation of white on belly in males and degree of pale upperparts spotting in females (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Race lonnbergi is small and males are especially dark, whereas race karelicus is paler and has well-developed white on belly. Race cantabricus is smaller than most, except aquitanicus, which differs from other W populations in that females are much darker and more heavily barred, with buff (rather than whitish) underparts; race major has extensively dark underparts and upperparts, while males have warm brown wings, but male rudolfi is even darker, and shorter-tailed, while race pleskei is difficult to distinguish from any of the races whose ranges it directly abuts; race obsoletus is one of the largest and darkest taxa, with dull, dark brown upperparts in male, which also has very small white patches on belly; race kureikensis is generally duller than the last subspecies, with cold grey neck, rump and flanks (like next race), paler back, and smaller size; male of race volgensis has quite pale grey head, neck and rump, and extensive grey-and-white marbling on posterior underparts; race uralensis is palest race; and male of race taczanowskii also has many pale grey feathers on head, neck and rump, and extensive white on belly, while female is yellowish brown above and whitish below (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ).

Editor's Note: This article requires further editing work to merge existing content into the appropriate Subspecies sections. Please bear with us while this update takes place.

• Western Capercaillie x Black Grouse (hybrid) Tetrao urogallus x Lyrurus tetrix

Editor's Note: Additional distribution information for this taxon can be found in the 'Subspecies' article above. In the future we will develop a range-wide distribution article.

Forest and woodland, mainly coniferous (especially Pinus sylvestris, but also Picea, Abies, etc.) or mixed coniferous deciduous; also isolated broadleaved forests (e.g. beech Fagus sylvatica and oak Quercus petraea, Q. pyrenaica) (4 Quevedo, M., Bañuelos, M.J., Sáez, O. and Obeso, J.R. (2006). Habitat selection by Cantabrian capercaillie Tetrao urogallus cantabricus at the edge of the species’ distribution. Wildl. Biol.. 12: 267–276. Close , 5 González, M.A., Olea, P.P., Robles, L. and Ena, V. (2010). The Mediterranean Quercus pyrenaica oak forest: a new habitat for the Capercaillie? Journal of Ornithology. 151(4): 901–906. Close ) in some parts of range, e.g. Cantabrian Mts (N Spain) and S Urals. Studies in Scotland have shown that some areas of otherwise suitable Pinus sylvestris forest are rendered unsuitable by high monoterpene levels in the needles, the production of which is genetically controlled, apparently due to counter-feeding by herbivores such as T. urogallus (6 Iason, G.R., O’Reilly-Wapstra, J.M., Brewer, M.J., Summers, R.W. and Moore, B.D. (2011). Do multiple herbivores maintain chemical diversity of Scots Pine monoterpenes? Phil. Trans. Roy. Soc. B.. 366: 1337–1345. Close ). Prefers extensive areas of old, shady forest, often with damp soil and interspersed by bogs, areas of peat or glades, and a dense undergrowth of ericaceous plants (Vaccinium, Calluna), but with the canopy neither too open or closed (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Old-growth forest with strong component of bilberry (Vaccinium myrtillus) in understorey is strongly selected in Norway (7 Gregersen, H. and Gregersen, F. (2008). Old bilberry forest increases likelihood of Capercaillie Tetrao urogallus lek occupancy in southern Norway. Ornis Norvegica. 31: 105–115. Close ). In winter, may select more open forest, at least in N, while during summer denser forest with abundant fruit bushes are preferred, especially by broods and moulting birds. Reaches 2000 m in Pyrenees (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ), where females regularly frequent alpine scrubland with their nestlings (8 Duriez, O. and Ménoni, E. (2008). Le Grand Tétras Tetrao urogallus en France : biologie, écologie et systématique. Ornithos. 15(4): 233–243. Close ), as well as in Altai Mts, and 1500 m in Carpathians.

Mainly sedentary, but often with local movements in winter in response to feeding requirements, e.g. in N Siberia, regularly moves from deciduous to coniferous woodland for winter, sometimes in the past in flocks of up to 50 individuals, although also singly. Females tend to move farther than males, as well as moving earlier (older birds first, young females second, thereafter old males and young males last), and same pattern is replicated among young in Scotland, where females also disperse longer distances (up to 30 km), in either their first autumn or next spring (9 Moss, R., Picozzi, N. and Catt, D.C. (2006). Natal dispersal of capercaillie Tetrao urogallus in northeast Scotland. Wildl. Biol.. 12: 227–232. Close ). Also some irregular movements, occasionally in excess of 1000 km, which may be eruptive; wandering birds even enter villages, where recorded crashing into buildings. However, even in S Siberia, the species is much less mobile, with longest movement in this region just 40 km and most birds being resighted within 6 km of their original locality, with few individuals of either sex wandering far from the lek. In NW Russia, there is evidence that youngsters emigrate from native forest to logged areas, with a reverse movement of mature males attempting to join large leks in native forest areas (10 Borchtchevski, V. and Moss, R. (2014). Age structure of Capercaillie males (Tetrao urogallus) in NW Russia may reflect two-way movements –– a hypothesis. Ornis Fennica. 91(1): 14––28. Close ). Brood home ranges in Bavarian Alps averaged 148 ha, between hatching and late summer (11 Storch, I. (1994). Habitat and survival of capercaillie Tetrao urogallus nests and broods in the Bavarian Alps. Biological Conservation. 70: 237–243. Close ), that of males in the early breeding season c. 47·5 ha (12 Wegge, P., Kvålsgard, T., Hjeljord, O. and Sivkov, A.V. (2003). Spring spacing behaviour of capercaillie Tetrao urogallus males does not limit numbers at leks. Wildl. Biol.. 9: 283–289. Close ), while in Russia and SE Norway males moved on average 2·3 km from their leks once display had ceased, only exceptionally travelling further than 6–7 km (13 Hjeljord, O., Wegge, P., Rolstad, J., Ivanova, M. and Beshkarev, A.B. (2000). Spring-summer movements of male capercaillie Tetrao urogallus: a test of the ‘landscape mosaic’ hypothesis. Wildl. Biol.. 6(4): 251–256. Close ).

During winter mainly pine needles , constituting up to 100% in Finland and Scotland, mostly P. sylvestris, but also P. cembra, P. uncinata, P. sibiricus, etc., in N Europe favouring the needles of diseased trees around bogs because of their higher nutritional value (more protein and less calcium), and up to 90% in Black Forest (14 Lieser, M. (1996). Zur Nahrungswahl des Auerhuhns Tetrao urogallus im Schwarzwald. Orn. Beob.. 93(1): 47–58. Close ), but autumn-released birds in Harz Mts, Germany, fed on spruce (Picea abies, 34%), bilberry (Vaccinium myrtillus, 26%) and herbs (20%), whereas the diet of tose released in spring was dominated by spruce (56%) and grass (20%) (15 Siano, R., Herzog, S.A., Exo, K.-M. and Bairlein, F. (2011). Nahrungswahl ausgewilderter Auerhühner (Tetrao urogallus L.) im Harz [Diet of Capercaillies (Tetrao urogallus L.) released in the Harz Mountains]. Vogelwarte. 49(2): 137–148. Close ). Tree-feeding in winter can last for five months in N, until absence of snow permits feeding on ground. In S, winter diet more varied (although at a microscale may be still dependent on just one or two species), e.g. in Cantabrian Mts, holly (Ilex aquifolium) leaves and birch (Betula) buds during snowy periods, with rockrose (Halimium lasianthum) a major food resource in autumn and winter and eaves, buds and acorns of Pyrenean oak (Quercus pyrenaica) throughout year (16 González, M.A., Olea, P.P., Mateo-Tomás, P., García-Tejero, S., de Frutos, Á., Robles, L., Purroy, S.J. and Ena, V. (2012). Habitat selection and diet of Western Capercaillie Tetrao urogallus in an atypical biogeographical region. Ibis. 154(2): 260–272 Close ), as well as buds of blaeberry/bilberry (Vaccinium myrtillus) and heaths (Erica) (17 Rodríguez, A.E. and Obeso, J.R. (2000). Diet of the Cantabrian Capercaillie: geographic variation and energetic content. Ardeola. 47(1): 77–83. Close , 18 Blanco-Fontao, B. and Quevedo, M. (2009). Diet and habitat selection in Cantabrian capercaillie: ecological differentiation of a southern edge population. Newsl. Galliformes Specialist Group 2: 28–31. Close ). Daily food intake in winter is typically c. 440–550 g for males (fresh weight). Inter-seasonal and summer food includes needles, leaves, stems and berries of a variety of plants, including juniper (Juniperus communis), blaeberry, whortleberry (Vaccinium uliginosum), crowberry (Empetrum nigrum), cloudberry (Rubus chamaemorus), cow wheat (Melampyrum pratense), woodrush (Luzula), sedges (Carex), horsetails (Equisetum), mosses, etc., with high protein foods especially important to females for egg production; in Black Forest, beech (Fagus) was main food plant in May (68%), leaves and stems of bilberry were also important in spring (maximum 29% in Jun), in summer and early autumn, they mostly fed on herbs (63% in Jul), grasses (one-third in Sept and Oct) and berries (20% in Jul and Aug) (14 Lieser, M. (1996). Zur Nahrungswahl des Auerhuhns Tetrao urogallus im Schwarzwald. Orn. Beob.. 93(1): 47–58. Close ). Insects (mainly Formicidae, Coleoptera, Diptera and especially Lepidoptera larvae in Scotland) (19 Baines, D., Wilson, I.A. and Beeley, G. (1996). Timing of breeding in Black Grouse Tetrao tetrix and Capercaillie Tetrao urogallus and distribution of insect food for the chicks. Ibis. 138(2): 181–187. Close , 20 Picozzi, N., Moss, R. and Kortland, K. (1999). Diet and survival of capercaillie Tetrao urogallus chicks in Scotland. Wildl. Biol.. 5(1): 11–23. Close , 21 Summers, R.W., Proctor, R., Thorton, M. and Avey, G. (2004). Habitat selection and diet of the Capercaillie Tetrao urogallus in Abernethy Forest, Strathspey, Scotland. Bird Study. 51(1): 58–68 Close ), spiders and molluscs are important only for chicks, until an age of c. 4 weeks (22 Wegge, P. and Kastdalen, L. (2008). Habitat and diet of young grouse broods: resource partitioning between Capercaillie (Tetrao urogallus) and Black Grouse (Tetrao tetrix) in boreal forests. Journal of Ornithology. 149(2): 237–244. Close ), with animal matter always constituting less than 10% of adult diet, even during moulting period. Among more unusual foods are apples in an orchard (23 Fuchs, W. (1995). Auerhahn frisst Äpfel in Obstanlage. Orn. Beob.. 92: 173–174. Close ). Forages mainly on ground between spring and autumn, but in tree canopy during winter (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Females and young form groups of up to 50 in autumn and winter (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) (formerly 100, with male-only flocks of up to 70 in past), at which time birds may roost in holes in the snow like some other grouse (24 Brenot, J.-F. and Fosty, P. (1994). Découverte de loges creusées sous la neige par le grand tétras Tetrao urogallus dans les Pyrénées. Alauda. 62(3): 147-148. Close ), provided it is deep enough, even consuming snow, apparently for its water content, while at other times of year the species is said to drink twice daily. In places where the species occasionally enters the tundra, e.g. N Urals and Kola Peninsula, it sometimes feeds in company of Lagopus muta.

Song (given by male) rather complex and audible over up to 200 m, commences with low-intensity ‘tapping phase’ during which emits disyllabic clicks , “TE-lip”, “Kikop”, followed by ‘drum-roll’ during which clicking notes are given much more rapidly, terminating in the ‘whetting phase’, characterized by a strangled, pig-like squealing sound, rendered “tzjiTHEthethetzjiTHEthethe” (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ), the whole performance lasting c. 5·5 seconds and given frequently, up to 7–8 times per minute during twilight and first hour or so of daylight. Western birds (nominate race, major, aquitanicus and cantabricus) also make popping sounds  (audible over 300 m) during central drum-roll (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ), which develops with age, being loudest in old males and weak and indistinct in first-year males. The birds also perform a ‘flutter-jump’ display, starting on ground and reaching up to 2 m above it, during which very low sounds are produced (infrasound), but it is currently unknown whether these are used in communication between males and females (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Male also utters harsh “koorKRERKkoroor” during ‘face-off’ with other male or when otherwise agitated, e.g. by human presence, as well as hissing or grunting clicks  towards rivals or perceived predators (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Although displays and therefore vocal sounds are concentrated in spring (as early as Feb) (25 Thiel, D., Ehrenbold, S. and Roth, T. (2005). Grosse Wintergruppen und Winterbalz beim Auerhuhn Tetrao urogallus [Large winter groups and early displaying behaviour of Capercaillie Tetrao urogallus]. Orn. Beob.. 102(1): 44–46. Close ), males can display during summer, autumn and even winter, albeit in latter season only very rarely. Female only really vocal during spring, when gives weak braying sound on arriving at male display area, a steadily repeated, chuckling “kok-kok”  , likened to that of Ring-necked Pheasant (Phasianus colchicus), in response to male’s display, and various other calls  including when with young (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Chicks give rather plaintive mewing sounds  .

Lays mainly in May (mid Apr to mid Jun); varies with latitude (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ). Promiscuous (or polygynous, with some males briefly possessing harems) (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ); males form ill-defined leks (mean number of males per lek 4·8 in Estonian study) (26 Viht, E (1991). Size and forest structure of displaying grounds of Capercaillie Tetrao urogallus pleskei at Alutaguse, north-east Estonia in 1979-1989. Ornis Scandinavica. 22: 294. Close ) spaced at c. 1·9–2·4 km intervals (27 Leclerq, B. (1990). La territorialité chez le Grand tétras (Tetrao urogallus major), structure et évolution des places de parade. Alauda. 58(1): 55. Close ), at which activity peaks for just 3–4 weeks, although overall display period can last from midwinter to late summer (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) (see Voice). Areas used for lekking may be of long-standing tradition, even for 100s of years. Each arena measured 12–67 ha in Estonian study, depending on number of males present (26 Viht, E (1991). Size and forest structure of displaying grounds of Capercaillie Tetrao urogallus pleskei at Alutaguse, north-east Estonia in 1979-1989. Ornis Scandinavica. 22: 294. Close ), exceptionally up to 150 ha elsewhere, while in French Pyrenees males attend smaller leks in more fragmented forest landscapes (28 Ménoni, É., Levet, M. and Landry, P. (1996). Cartographie de l'habitat du Grand Tétras en France Tetrao urogallus un exemple d'application : effet de sa fragmentation sur une population Pyrénéenne. Alauda. 64(2): 239–248. Close ) and in SE Europe arenas are typically just 1–2 ha, with up to five males, whereas largest leks in present day may be attended by up to 70 males. Females principally visit leks between dawn and 09:00 hours, although males lek at any time of day (29 Ruddock, M., and D. P. Whitfield (2007). A review of disturbance distances in selected bird species. Report to Scottish Natural Heritage. Close ). The number of males present at an individual lek appears to be determined by habitat quality (27 Leclerq, B. (1990). La territorialité chez le Grand tétras (Tetrao urogallus major), structure et évolution des places de parade. Alauda. 58(1): 55. Close ); at Estonian leks trees mostly 81–126 years old, with a height of 10–18 m, and usually no undergrowth (26 Viht, E (1991). Size and forest structure of displaying grounds of Capercaillie Tetrao urogallus pleskei at Alutaguse, north-east Estonia in 1979-1989. Ornis Scandinavica. 22: 294. Close ). Male activity and behaviour at leks shows a hierarchial structure according to age (30 Catusse, M. (1992). Ontogénèse du système de reproduction des mâles de Grand Tétras observé sur une arène des Pyrénées centrales. Alauda. 60(1): 81–92. Close ). Nest (constructed by female) (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) is shallow depression, scantily lined with grass, pine needles, twigs or some feathers, in dense cover, often at base of tree (rarely in old nest of large bird, placed low in tree) (31 Harrison, C. J. O., and P. Castell (2002). Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition. HarperCollins, London, UK. Close ). In Bavarian Alps, females strongly favour edge habitats for nesting (32 Storch, I. (1991). Habitat fragmentation, nest site selection, and nest predation risk in Capercaillie. Ornis Scandinavica. 22: 213–217. Close ). Normally 6–9 pale yellow eggs with some buff to reddish-brown markings (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ) (4–12, mean 6·5 eggs in Pyrenees and 7·25 in Soctland (33 Summers, R.W., Willi, J. and Selvidge, J. (2009). Capercaillie Tetrao urogallus nest loss and attendance at Abernethy Forest, Scotland. Wildl. Biol.. 15: 319–327. Close ), while elsewhere reports of 12–18 eggs may indicate two females laying in same nest) (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close , 34 Storch, I. and Segelbacher, G. (2005). Two grouse clutches in the same nest: evidence for nest site adoption in capercaillie (Tetrao urogallus). Journal of Ornithology. 146(1): 85–88. Close ), laid on alternate days (exceptionally up to four days apart), mean size 57·3 mm × 41·5 mm (31 Harrison, C. J. O., and P. Castell (2002). Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition. HarperCollins, London, UK. Close ), mass c. 53 g, but size varies with age of female and regionally; incubation c. 24–29 days by female alone (31 Harrison, C. J. O., and P. Castell (2002). Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition. HarperCollins, London, UK. Close ), starting before last egg is laid; eggs hatch synchronously (1 Madge, S., and P. McGowan (2002). Pheasants, Partridges and Grouse, including Buttonquails, Sandgrouse and Allies. Christopher Helm, London, UK. Close ); downy chick (hatch weight 36–45 g) lacks brown on crown and has characteristic black V mark on forehead; flight feathers and upperwing-coverts start to develop at hatching, and chick able to fly reasonably well at 2–3 weeks (and short distances when just 4–5 days old); first primary shed at 14–17 days (31 Harrison, C. J. O., and P. Castell (2002). Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition. HarperCollins, London, UK. Close ). Sex ratio on hatching favours females in several regions, including Scotland (35 Moss, R., Picozzi, N., Summers, R.W. and Baines, D. (2000). Capercaillie Tetrao urogallus in Scotland – demography of a declining population. Ibis. 142(2): 259–267. Close ), N & E Finland (36 Helle, P., Kurki, S. and Lindén, H. (1999). Change in the sex ratio of the Finnish capercaillie Tetrao urogallus population. Wildl. Biol.. 5(1): 25–31. Close ) and Russian Karelia, but males frequently outnumber females among adults, even in some of same areas, and percentage of males increases with annual breeding success (37 Hörnfeldt, B., Hipkiss, T. and Eklund, U. (2001). Juvenile sex ratio in relation to breeding success in Capercaillie Tetrao urogallus and Black Grouse T. tetrix. Ibis. 143(3): 627–631. Close ). Nests occasionally parasitized by Phasianus colchicus and Lyrurus tetrix (38 Krakauer, A. H., and R. T. Kimball (2009). Interspecific brood parasitism in galliform birds. Ibis 151(2):373–381. Close ). Clutches that hatch, 84–94% for different years in Finland, where another study revealed 60% of eggs laid produced chicks that were still alive in late Aug; in Bavarian Alps, eggs in two-thirds of nests hatched, and one-fifth of chicks survived until autumn (11 Storch, I. (1994). Habitat and survival of capercaillie Tetrao urogallus nests and broods in the Bavarian Alps. Biological Conservation. 70: 237–243. Close ). In Spanish Pyrenees, multi-year study at various sites found that breeding success varied from 0·2–1·8 young per female per annum (39 Canut, J., Garcia, D., Marco, X., Catus Se, M., Menoni, E. and Novoa, C. (1996). Métodos de censo para la obtenciôn de los parametros reproductores del urogallo Tetrao urogallus en los Pirineos: comparación y recomendaciones para su aplicación. Alauda. 64(2): 195–204. Close ), while in Scotland 11 of 20 nests were predated at egg stage, most by pine martens (Martes martes) (33 Summers, R.W., Willi, J. and Selvidge, J. (2009). Capercaillie Tetrao urogallus nest loss and attendance at Abernethy Forest, Scotland. Wildl. Biol.. 15: 319–327. Close ). Females may be extremely sensitive to disturbance during incubation period (40 Kjaer, D. (1991). The Capercaillie in Scotland. Birding World. 4(2): 60–62. Close ) and rates of nest predation by mammals can be very high (66%) but are lowest in edge habitats (32 Storch, I. (1991). Habitat fragmentation, nest site selection, and nest predation risk in Capercaillie. Ornis Scandinavica. 22: 213–217. Close ). Re-nesting common, with up to 87% (mean 36% in one study) of females that lost first clutch electing to attempt second nest, and this can have a significant effect on overall breeding success (41 Storaas, T., Wegge, P. and Kastdalen, L. (2000). Weight-related renesting in capercaillie Tetrao urogallus. Wildl. Biol.. 6: 299–303. Close ). Heavy and prolonged rainfall during hatching period, when chicks still small, can be highly detrimental to their survival (42 Baines, D. (1991). Factors contributing to local and regional variation in Black Grouse breeding success in northern Britain. Ornis Scandinavica. 22: 264–269. Close ), while wild boars (Sus scrofa) locally can very negatively effect nesting success (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ). Sexual maturity in first year, but males do not mate before three and it is probable that only first-year females above a certain mass threshold actually nest. Annual survival rate c. 60% in adult males, but lower in adult females, and mortality of adults of both sexes highest in winter, with lower peak for males in spring (44 Ellison, L.N. (1991). Shooting and compensatory mortality in tetraonids. Ornis Scandinavica. 22: 229–240. Close ); one survived to 13·5 years old; in captivity may live up to 18 years or more. Captive-bred young released in autumn were heavily predated by foxes, martens and Northern Goshawks (Accipiter gentilis) (35 Moss, R., Picozzi, N., Summers, R.W. and Baines, D. (2000). Capercaillie Tetrao urogallus in Scotland – demography of a declining population. Ibis. 142(2): 259–267. Close ) and efforts to reestablish populations in Germany through translocations and introductions have failed to become self-sustaining (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ).

Not globally threatened (Least Concern). Cyclical population changes probably linked to food quality, specifically bilberry (Vaccinium myrtillus) production in some areas (45 Selås, V. (2000). Population dynamics of capercaillie Tetrao urogallus in relation to bilberry Vaccinium myrtillus production in southern Norway. Wildl. Biol.. 6(1): 1–11. Close ). Still occupies most of original range, although serious declines in W & C Europe have led to extinctions in Ireland (principally due to habitat loss) (44 Ellison, L.N. (1991). Shooting and compensatory mortality in tetraonids. Ornis Scandinavica. 22: 229–240. Close ), Great Britain (lost from England by 1665) (40 Kjaer, D. (1991). The Capercaillie in Scotland. Birding World. 4(2): 60–62. Close ), Belgium, most of France and Germany, Hungary, locally in Czech Republic (46 Porkert, J. (1991). Hoarfrost deposits as a factor contributing to the extinction of tetraonids in the eastern Sudetes. Ornis Scandinavica. 22(3): 292–293. Close ) and many other areas, with dramatic declines registered in Poland (47 Zawadzki, J. and Zawadzka, D. (2012). Population decline of Capercaillies Tetrao urogallus in the Augustów Forest (NE Poland). Acta Ornithologica. 47(2): 199–204. Close ), Estonia (4500–5000 individuals in mid 1990s) (48 Viht, E. (1997). Protection of the capercaillie Tetrao urogallus in Estonia. Wildl. Biol.. 3(3–4): 293. Close ), Lithuania and Slovakia; now mainly confined to mountains and N. Race cantabricus of Cantabrian Mts considered Endangered in Red Data Book of 1978/79 and remain so (49 Storch, I., Bañuelos, M.J., Fernández-Gil, A., Obeso, J.R., Quevedo, M. and Rodríguez-Muñoz, R. (2006). Subspecies Cantabrian capercaillie Tetrao urogallus cantabricus endangered according to IUCN criteria. Journal of Ornithology. 147(4): 653–655. Close ); c. 600 males in 1980, but between 1981 and 2003 the range of this population shrank by 66% (from 2,070 km² to 693 km²) and the population by c. 70% (based on counts of singing males) (50 Pollo, C.J., Robles, L., Seijas, J.M., García-Miranda, Á. and Otero, R. (2005). Trends in the abundance of Cantabrian Capercaillie Tetrao urogallus cantabricus at leks on the southern slope of the Cantabrian Mountains, north-west Spain. Bird Conservation International. 15(4): 397–409. Close ), while at least some subpopulations are apparently becoming genetically isolated (51 Alda, F., Sastre, P., De La Cruz-Cardiel, P. J. and Doadrio, I. (2011). Population genetics of the endangered Cantabrian capercaillie in northern Spain. Animal Conservation. 14(3): 249–260. Close ) and smaller forest patches have been abandoned during recent decades (4 Quevedo, M., Bañuelos, M.J., Sáez, O. and Obeso, J.R. (2006). Habitat selection by Cantabrian capercaillie Tetrao urogallus cantabricus at the edge of the species’ distribution. Wildl. Biol.. 12: 267–276. Close , 52 Quevedo, M., Bañuelos, M.J. and Obeso, J.R. (2006). The decline of Cantabrian capercaillie: How much does habitat configuration matter? Biological Conservation. 127: 190–200 Close ); however, improved and more complete censusing methods suggests overall population is currently c. 1000 birds (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ). Genetic isolation is also increasing elsewhere through the species’ W & C European range (53 Segelbacher, G., Höglund, J. and Storch, I. (2003). From connectivity to isolation: genetic consequences of population fragmentation in capercaillie across Europe. Molecular Ecology. 12(7): 1773–1780. Close ), thus maintaining habitat connectivity between subpopulations in regions such as the Alps is vital (54 Segelbacher, G. and Storch, I. (2002). Capercaillie in the Alps: genetic evidence of metapopulation structure and population decline. Molecular Ecology. 11(9): 1669–1677. Close ). Largest numbers in Russia, where as many as 6,000,000–7,000,000 were said to survive in 1960s, subsequently just 1,500,000 in 1970s, but the total has since been revised upwards again, to c. 2,200,000–3,000,000 individuals. In Pyrenees, c. 2500 birds estimated in Spain (and population at least locally stable, e.g. within Parc Natural de Cadí-Moixeró) (55 Garcia Petit, J. (1996). Evolució de la població de gall fer Tetrao urogallus al Parc Natural del Cadí-Moixeró en els darrers 15 anys (1981-1995). Alauda. 64(2): 261–263. Close ), and c. 4000 males in France (8 Duriez, O. and Ménoni, E. (2008). Le Grand Tétras Tetrao urogallus en France : biologie, écologie et systématique. Ornithos. 15(4): 233–243. Close ); in Alps, recently extinct in France (elsewhere in the country c. 340 adults in the Jura (56 Montadert, M. (2013). Statut actuel et variations d’abondance du Grand Tétras Tetrao urogallus dans le massif jurassien français [Distribution, numbers and population trend of the Western Capercaillie in the French Jura mountains]. Alauda. 81(1): 1–18. Close ), 200 males in the Vosges and a reintroduced population in the Cévennes of at most 50 individuals) (8 Duriez, O. and Ménoni, E. (2008). Le Grand Tétras Tetrao urogallus en France : biologie, écologie et systématique. Ornithos. 15(4): 233–243. Close ), at most c. 1100 males in Switzerland (where population has halved during last c. 30 years) (57 Mollet, P., Badilatti, B., Bollmann, K., Graf, R.F., Hess, R., Jenny, H., Mulhauser, B., Perrenoud, A., Rudmann, F., Sachot, S. and Studer, J. (2003). Verbreitung und Bestand des Auerhuhns Tetrao urogallus in der Schweiz 22692691 und ihre Veränderungen im 19. und 2269. Jahrundert [Numbers and distribution of Capercaillie Tetrao urogallus in Switzerland 22692691 and their changes in the 19th and 2269th century]. Orn. Beob.. 100: 67–86. Close ), 6500–9000 birds in Italy, and c. 10,000 males in Austria; just 750–1200 territories in Germany (58 Gedeon, K., C. Grüneberg, A. Mitschke, C. Sudfeldt, W. Eikhorst, S. Fischer, M. Flade, S. Frick, I. Geiersberger, B. Koop, M. Kramer, T. Krüger, N. Roth, T. Ryslavy, S. Stübing, S. R. Sudmann, S. Steffens, F. Vökler, and K. Witt (2014). Atlas Deutscher Brutvogelarten [Atlas of German Breeding Birds]. Stiftung Vogelmonitoring Deutschland und Dachverband Deutscher Avifaunisten, Münster, Germany. Close ). In Scotland, where extinct from 1785 (and now Red-listed) (59 Holling, M., and The Rare Breeding Birds Panel (2011). Rare breeding birds in the United Kingdom in 2009. British Birds 104(9):476–537. Close ), successfully reintroduced in 1836–1837 (60 Starling, A.E. (1991). Workshop summary: Captive breeding and release. Ornis Scandinavica. 22(3): 255–257. Close ) and by 1862 there were 2000 individuals on the same estate in Perthshire (60 Starling, A.E. (1991). Workshop summary: Captive breeding and release. Ornis Scandinavica. 22(3): 255–257. Close ); however, countrywide numbers estimated at c. 2200 birds in early 1990s (61 Catt, D.C., Baines, D., Picozzi, N., Moss, R. and Summers, R.W. (1998). Abundance and distribution of capercaillie Tetrao urogallus in Scotland 1992–1994. Biological Conservation. 85: 257–267. Close , 62 Ogilvie, M., and the Rare Breeding Birds Panel (1999). Non-native birds breeding in the United Kingdom in 1996. British Birds 92(4):176–182. Close ), c. 1075 in winter 1998/99 (63 Wilkinson, N.I., Langston, R.H.W., Gregory, R.D., Gibbons, D.W. and Marquiss, M. (2002). Capercaillie Tetrao urogallus abundance and habitat use in Scotland, in winter 1998–99. Bird Study. 49(2): 177–185 Close ), 1980 birds in winter 2003/04 (64 Eaton, M.A., Marshall, K.B. and Gregory, R.D. (2007). Status of Capercaillie Tetrao urogallus in Scotland during winter 283833/834. Bird Study. 54(2): 145–153 Close , 59 Holling, M., and The Rare Breeding Birds Panel (2011). Rare breeding birds in the United Kingdom in 2009. British Birds 104(9):476–537. Close ), c. 1285 in 2009/10 (65 Ewing, S.R., Eaton, M.A., Poole, T.F., Davies, M. and Haysom, S. (2012). The size of the Scottish population of Capercaillie Tetrao urogallus: results of the fourth national survey Bird Study. 59(2): 126–138. Close ) and is still declining, with just 202 lekking males in 2012 (66 Holling, M., and The Rare Breeding Birds Panel (2014). Rare breeding birds in the United Kingdom in 2012. British Birds 107(9):504–560. Close ) and 193 in 2013 (67 Holling, M., and the Rare Breeding Birds Panel (2015). Rare breeding birds in the United Kingdom in 2013. British Birds 108(7):373–422. Close ), and climate change postulated to be playing an important role in this process (68 Moss, R., Oswald, J. and Baines, D. (2001). Climate change and breeding success: decline of the capercaillie in Scotland. Journal of Animal Ecology. 70(1): 47–61. Close ), although changes in silviculture, increased predation, overshooting, overgrazing by red deer (Cervus elaphus) and collisions with fences are also implicated (69 Proctor, R. and Summers, R.W. (2002). Nesting habitat, clutch size and nest failure of Capercaillie Tetrao urogallus in Scotland. Bird Study. 49(2): 190–192 Close ). Also declining, though generally more secure, in Fennoscandia, where during 1960s there were an estimated 300,000–400,000 males in Norway (but had declined by c. 35% by 2000s, especially in S & N) (70 Gregersen, F. and Gregersen, H. (2009). Ongoing population decline and range contraction in Norwegian forest grouse. Ornis Norvegica. 32: 179–189. Close ) and 600,000 in Finland . There are an estimated 10,000 birds in Romania (71 Kalabér, L.V. (1998). The status of the Capercaillie Tetrao urogallus, Hazel Grouse Tetrastes bonasia and Black Grouse Lyrurus tetrix in Romania. Ostrich. P. 291 in:. Close ). In Ukraine, occurs in Poles’ye zone and Carpathians, where common and fairly numerous at end of 19th century; has declined rapidly since 1960s, due to deforestation, amelioration of climate, pesticides, disturbance and poaching; total population now reckoned to number 4400–5300 birds; protected in three nature reserves and suffers no hunting pressure. In addition to Scotland, the species has also been successfully reintroduced to N Kazakhstan, in 1965, following its extirpation there in the early 20th century. Many estimates of densities available, ranging from 0·1 males/km² in primeval forest of Bialowieza (NE Poland) to 24 birds/km² in natural pine forests in Scotland, but most typically c. 0·5–1·0 males/km². Still commonly hunted (even during breeding season) (72 Baines, D. and Lindén, H. (1991). Workshop summary: The impact of hunting on grouse population dynamics. Ornis Scandinavica. 22(3): 245–246. Close ), except in SW & C Europe (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ), with annual bags as follows: in Sweden c. 16,000 birds in 1978–1980; in Norway c. 13,000 in 1980, but c. 40,000 around 1960; and in Finland 14,500–33,000 in 1969–1976, but up to 104,000 during early 1960s (numbers taken are usually cyclical, with more being hunted during periods of greater abundance due to breeding success, etc.) (73 Lindén, H. (1991). Patterns of grouse shooting in Finland. Ornis Scandinavica. 22(3): 241–244. Close ). Main threat is destruction or alteration of woodland, with fires being especially deleterious, as pines burn more easily. Afforestation has locally fostered some recoveries, but modern forestry practices generally detrimental (74 Klaus, S. (1991). Effects of forestry on grouse populations: case studies from the Thuringian and Bohemian forests, Central Europe. Ornis Scandinavica. 22(3): 218–224. Close ). Other factors possibly involved in declines include excessive shooting, disturbance (e.g. development of ski facilities (75 Brenot, J.-F., Catusse, M. and Menoni, E. (1996). Effets de la station de ski de fond du plateau de Beille (Ariège) sur une importante population de Tetrao urogallus. Alauda. 64(2): 249–260. Close ) and other winter recreation activities (76 Thiel, D., Jenni-Eiermann, S., Palme, R. and Jenni, L. (2011). Winter tourism increases stress hormone levels in the Capercaillie Tetrao urogallus. Ibis. 153(1): 122–133. Close ) ), collisions (especially of juveniles) with high-tension powerlines (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ) and in some areas fences (35 Moss, R., Picozzi, N., Summers, R.W. and Baines, D. (2000). Capercaillie Tetrao urogallus in Scotland – demography of a declining population. Ibis. 142(2): 259–267. Close ), predation (e.g. by foxes) (43 Storch, I. (2007). Grouse: Status Survey and Conservation Action Plan 27747746–27741774. IUCN, Gland & World Pheasant Association, Fordingbridge. Close ), pollution (acid rain) and climatic changes, e.g. in Scotland (77 Harrison, P.A., Vanhinsbergh, D.P., Fuller, R.J. and Berry, P.M. (2003). Modelling climate change impacts on the distribution of breeding birds in Britain and Ireland. Journal for Nature Conservation. 11(1): 31–42. Close ) and former East Germany (78 Klaus, S., Berger, D. and Huhn, J. (1997). Capercaillie Tetrao urogallus decline and emissions from the iron industry. Wildl. Biol.. 3: 131–136. Close ). Suggested guidelines for buffer zones around leks and breeding areas have been made in the UK (29 Ruddock, M., and D. P. Whitfield (2007). A review of disturbance distances in selected bird species. Report to Scottish Natural Heritage. Close ) and it has been suggested that this capercaillie would make a candidate umbrella species for the conservation of taiga forests (79 Pakkala, T., Pellikka, J. and Lindén, H. (2003). Capercaillie Tetrao urogallus - a good candidate for an umbrella species in taiga forests. Wildl. Biol.. 9: 309–316. Close ).