关键词: Tragopan temminckii, Ithaginis cruentus, 同域分布, 海拔, 觅食生境选择

Abstract

Temminck’s tragopan (Tragopan temminckii) and blood pheasant (Ithaginis cruentus) are two threatened species mainly distributed in China. However, we know little about the ecology of these two pheasants. Between May and August in 2006, we investigated foraging habitat selection by the two sympatric species in Liziping Nature Reserve in Sichuan Province, China, using line transect and systematic sampling methods. Temminck’s tragopans occurred at relatively low altitudes (1,950-3,450 m), while blood pheasants occurred at higher altitudes (2,760-3,800 m). No differences were found between the two species in terms of use of forest types. Both species preferred coniferous and mixed coniferous-broadleaved forest and they seldom occurred in forest areas with dense arrow bamboo (Fargesia spathacea). At the microhabitat scale, both species were consistently associated with dense tree coverage, and dense coverage of tall herbaceous plants. Home ranges of the two species contained more coniferous trees than random, and foraging sites were close to forest roads. We did detect some habitat use differences between the two species. Blood pheasant foraging habitats were associated with southwest-facing slopes, while Temminck’s tragopans did not select sites based on aspect. The habitats of Temminck’s tragopans were associated with lower arrow bamboo and sparse bamboo coverage compared to the control sites. There were more mixed coniferous-broadleaved forests and less forest-bamboo mixed forests in Temminck’s tragopans’ home ranges than in blood pheasants’ home ranges. We suggest that basic differences in habitat use can explain how the two species are able to maintain sympatric distributions.

Key words: Tragopan temminckii, Ithaginis cruentus, sympatric, altitude, foraging habitat selection