Taxonomy
Authors disagree about the
scientific name of the species. Here, we follow Sibley and Monroe
1990, 1993 and del Hoyo et al. 1994. Andreev (1991), Klaus et al.
1989, and S. Klaus (pers. comm.), however, favour the earlier name
T. urogalloides.
A distinct and
geographically isolated subspecies T. p. kamschatikus on
the Russian peninsula of Kamtchatka is generally recognised. The
distinction of subspecies within the mainland distribution range
has been more ambiguous; now both Potapov and Flint (1989) and del
Hoyo et al. 1994 recognise three subspecies; two on the mainland,
T. p. parvirostris and stegmanni, and
kamtschatikus on Kamtchatka.
Distribution
North-east Asia. The major
part of the range is in Russia, smaller parts in Mongolia and
China. From the Japanese sea, the Kamtchatka peninsula and the
island of Sachalin west up to approx. 90°E; north up to
70°N and locally beyond, and south to about 45°N in
northern Mongolia and China. The range largely corresponds with
that of the larch species Larix dahurica and L. gmelinii. In the
west of the range, some overlap and hybridisation with the
capercaillie T. urogallus occurs (see Klaus et al. 1989, Potapov
and Flint 1989).
Population size and trend
The distribution of the
species still is largely limited by natural factors (A. Andreev
pers. comm.). Reported population densities are highly variable
between 1-5 to >100 males per 100km_. Locally, and particularly
in the southern parts of the range, the species has declined
dramatically in relation to human population growth, road
construction, and increasing accessibility of the habitats.
Intensive hunting at the leks may be a major cause of population
declines (A. Andreev and S. Klaus, pers. comm). The total
population size was estimated as 670,000 in the early 1990s (Flint
1995); earlier estimates had been higher (Klaus et al. 1989).
Larger-scale population trends are insufficiently known.
Habitat and ecology
Compared to the western
capercaillie, the black-billed capercaillie appears to be
generally adapted to more open habitats. Its distribution is
closely related to larch taiga forest, both in lowland and
mountainous areas, extending from wooded tundra in the north to
woody steppes in the south. On Kamtchatka the species is also
found in stands dominated by birch Betula ermani. Black-billed
capercaillie are well known to significantly influence and modify
their habitats by creating so-called park forests or capercaillie
gardens (Klaus et al. 1989, Andreev 1991). By seasonally trimming
small larch trees, the birds suppress vertical growth,
transforming the trees to a dwarf form. As a result of annual
trimming, the dwarf larches are prevented from growing upwards
(Andreev 1991). Larch and birch twigs and shoots and rosehips are
major food items in winter. From spring to summer, a wide variety
of herbs, grasses, and invertebrates is eaten, but ericaceous
shrubs play a prominent role in the diet. In the course of the
year, black-billed capercaillie use different habitats in relation
to food availability. Undirectional movements between seasonal
habitats of a few up to >15km have been described. Locally, the
birds form temporal winter flocks (see Klaus et al. 1989, Potapov
and Flint 1989).
Hunting and cultural
importance
The species is an important
game bird in Russia. In accessible areas close to roads and
settlements, intensive hunting at the leks is common, and may be a
major cause of the recent population declines.
Principal
threats
Exploitation.
Increasing accessibility of the forests and growing human
populations in parts of the range, particularly in the south, have
led to increasing hunting pressure. Poaching is common, and may
lead to dramatic declines.
Habitat degradation.
The insecure socio-economic situation in Russia may pose
significant threats to forest habitats. The demand for resources
is great, both by the state and by local inhabitants. Uncontrolled
timber exploitation is going on in many parts of Russia. Habitat
loss and deterioration related to forest exploitation may become
major threats to the black billed capercaillie. In China, habitat
degradation already is the major threat in addition to small
population size; only a minor part of the range is outside Russia,
however.
Research needs
Better understanding is
needed of the species´ population dynamics and regulating
factors.
Current conservation
measures
At present, no specific
conservation measures for the black-billed capercaillie are known.
The species occurs in a number of protected areas (Zapovedniki) in
Russia; at present, they probably do not effectively reduce
illegal exploitation.
Priority conservation
measures
Legal protection. A
revision and enforcement of hunting regulations is needed. The
hunting season should be limited to October-January (Potapov and
Flint 1989).
Surveys. At least
locally, dramatic declines related to exploitation and habitat
degradation have been reported. Regular surveys are recommended to
better observe the population trend in areas settled and exploited
by people.
Correspondents
Alexander Andreev,
Siegfried Klaus
Key
publications
Andreev, A. V.
1991 Winter habitat segregation in the sexually dimorphic
Black-billed capercaillie. Ornis Scandinavica 22:287-291.
Klaus, S.,
Andreev, A.V., Bergmann, H.-H., Müller, F. , Porkert, J. and
Wiesner, J. 1989. Die Auerhühner. Die Neue
Brehm-Bücherei. Band 86. Westarp Wissenschaften, Magdeburg,
Germany, pp. 221-280.
Potapov, R. L.
and Flint, V. E. 1989. Handbuch der Vögel der Sowjetunion.
Band 4 Galliformes, Gruiformes. 427 pp. Ziemsen Verlag Wittenberg
Lutherstadt, Germany. (ISBN 3-7403-0027-2)
