Tetrao Urogallus (Western Capercaillie)

Pine forests, preferably old ones, are Capercaillies’ domain. In spring they gather at leks to display and mate. Often the leks vary from year to year, and also the centre of the lek can shift from one day to the other, making it hard to predict the exact spot.

In western Finland, their display season approaches its peak towards the end of April, early May. That’s when the females are finally arriving at the lek to observe, and to select their mating partner. With the hens gathering to the nearby trees, the males perform showy flutter-jumps, making a lot of noise with their wings, and occasionally burst into wild, short display flights.

Western capercaillies are large grouse that exhibit extreme sexual dimorphism. Males are the largest of the grouse family, ranging from 4 to 5 kg while females weigh no more than 2 kg. Males are distinguished by their dark black body color, iridescent blue and green, and vibrant red combs over the eye. Their fanlike tail is used for displaying to females. Female western capercaillies are similar to female black grouse (Lyrurus tetrix), but are larger and have warmer brown coloration on her body. Females are distinguished by the rosy-rufous color on their throat, breast, and tail. (EU Wildlife and Sustainable Farming Project, 2009)

Tetrao urogallus (western capercaillies) have a Palearctic distribution. They are a non-migratory species, although hens with broods seem to use the same route to travel in search of high-quality insects for multiple years in succession. The northern boundary of their range reaches as far north as Scandinavia and continuously extends eastward into eastern Siberia. Further south in temperate Europe, western capercaillie populations occur in fragments. Prior to the second half of the 20th century, forestry practices and efforts to improve habitat lead to range expansion and high connectivity. During this time the connected habitats probably functioned as meta-populations. Western capercaillie populations are now declining in most of their central European range due to habitat deterioration and human disturbance. (Segelbacher, et al., 2003; Storch, 2000; Wegge, et al., 2007)

 Other Physical Features

  • endothermic
  • homoiothermic
  • bilateral symmetry
Sexual Dimorphism

  • male larger
  • sexes colored or patterned differently
  • male more colorful
  • ornamentation
Bird's sound (type: call) ➽ Click to hear

Phot location: Jalasjärvi, Finland

Photo info - 28.04.2014: Canon EOS-1D X, 165 mm, ISO 3200, f 3, 1/1250 sec, Flash: not used

Tags: capercaillie, display, display jump, flutter jump, lek, markus varesvuo, mature pine forest, spring