Cantabrian capercaillie (Tetrao urogallus cantabricus)
Species Description
The Cantabrian capercaillie (Tetrao urogallus cantabricus) is a subspecies of the western capercaillie (T. urogallus) in the family Tetraonidae. The species in general is a large grouse, of 80 to 115 centimeters (cm) in length (31 to 45 inches (in)), and the female is much smaller than the male. The species is characterized by having dark gray plumage with fine blackish vermiculation (wavelike pattern) around the head and neck. The breast is glossy greenish-black. This bird has a long, rounded tail, an ivory white bill, and a scarlet crest (World Association of Zoos and Aquaria 2009, unpaginated).
The Cantabrian capercaillie once existed along the whole of the Cantabrian mountain range from northern Portugal through Galicia, Astruias, and Leon, to Santander in northern Spain (IUCN Redbook 1979, p.1). Currently its range is restricted to the Cantabrian mountains in northwest Spain. The subspecies inhabits an area of 1,700 square kilometers (km2) (656 square miles (mi2)), and its range is separated from its nearest neighboring subspecies of capercaillie (T. u. aquitanus) in the Pyrenees mountains by a distance of more than 300 km (186 mi) (Quevedo et al. 2006b, p. 268).
The Cantabrian capercaillie occurs in mature beech (Fagus sylvatica) forest and mixed forests of beech and oaks (Quercus robur, Q. petraea, and Q. pyrenaica) at elevations ranging from 800 to 1,800 m (2,600 to 5,900 ft). The Cantabrian capercaillie also uses other microhabitat types (broom (Genista spp.), meadow, and heath (Erica spp.)) selectively throughout the year (Quevedo et al. 2006b, p. 271). The species feeds on beech buds, catkins of birch (Betula alba), and holly leaves (Ilex aquifolium). It also feeds on bilberry (Vaccinium myrtillus), a commonly eaten component of its diet (Rodriguez and Obeso 2000 as reported in Pollo et al. 2005, p. 398).
Storch et al. estimates the population to be 627 birds, of which approximately 500 are adults, according to the most recent population data collected from 2000 through 2003 (2006, p. 654). Population estimates for species of grouse are commonly assessed by counting males that gather during the leks (traditional places where males assemble during the mating season and engage in competitive displays that attract females). Pollo et al. (2005, p. 397) estimated a 60-to-70 percent decline in the number of male leks since 1981. This is equivalent to an average decline of 3 percent per year, or 22 percent over 8 years. There is also evidence of a 30-percent decline in lek occupancy in the northern watershed of the species’ range between 2000 and 2005 (Banuelos and Quevedo, unpublished data, as reported in Storch et al. 2006, p. 654). Based on data collected between 2000 and 2003 by Pollo et al. (2005, p. 401), the distribution of Cantabrian capercaillie on the southern slope of the Cantabrian Mountains is fragmented into 13 small subpopulations: four in the western area and 9 in the eastern. Six subpopulations (5 in the eastern and 1 in the western) contained only one singing male, which indicates a very small subpopulation, since presence of singing males is a direct correlate to population numbers. The area occupied by Cantabrian capercaillie in 1981–1982 covered up to approximately 2,070 km2 (799 mi2) of the southern slope 972 km2 (375 mi2) in the west and 1,098 km2 (424 mi2) in the east). Between 2000 and 2003, the area of occupancy had declined to 693 km2 (268 mi2), specifically 413 km2 (159 mi2) in the west and 280 km2 (108 mi2) in the east. Thus, over a 22–year period, there was a 66-percent reduction in the areas occupied by this subspecies on the southern slope of the Cantabrian Mountains (Pollo et al. 2005, p. 401). Based on this data, the subpopulation in the eastern portion of the range appears to be declining at a faster rate than the subpopulation in the western portion of the range.
Conservation Status
Although Storch, et al. 2006 (p. 653) noted that the Cantabrian capercaillie meets the criteria to be listed as ‘‘Endangered’’ on the IUCN Redlist due to ‘‘rapid population declines, small population size, and severely fragmented range,’’ it is currently not classified as such by the IUCN. The species is classified as ‘‘vulnerable’’ in Spain under the National Catalog of Endangered Species. The species has not been formally considered for listing in the CITES Appendices (http:// www.cites.org).