Mountain Broadleaved Forest Winter Bird Community Structure And The Years Before And After The Change

We studied the wintering birds community structure of mountainous secondary broadleaf forest in the natural protective area of Zuojia, Jilin Province during the periods from November, 1989 to February, 1990 and from November, 2001 to February, 2002. We compare the changes of birds community for 12 years fore-and-aft.We investigated for 144.5 hours in 28 days in field during two winters, and collected about 20 thousands data. The work was expanded on the same plots in 12 years ago and today, and the investigation data of 12 years ago can be used to compare with that of today.By studying the birds composition, quantity, species diversity and evenness, consumer biomass of community; feeding niche, gathering and encountering probability of birds, we illustrate the characteristics of mountainous secondary forests wintering birds community in temperate zone in northeast China, and the changing trends and the relation with environments of birds community for 12 years fore-and-aft.The main results are as follows:1 The birds communities consist of 19 and 20 species respectively 12 years fore-and-aft in our investigation during two winter, there 17 species are same in the two bird communities. The bird community can be named by Marsh Tit (Parus palustris), Long-tailed Tit (Aegithalos caudatus), and Dusky Thrush (Turdus naumanni). There exist little change both between species composition and quantity for 12 years fore-and aft.2 The index of species diversity and evenness of wintering birds community during the period from 2001 to 2002 are higher than which investigated during the period 1989 to 1990. The consumer biomassinvestigated former is higher than that investigated today. The t-test result shows that the species diversity index, evenness index and consume biomass are no significant differences between 12 years fore-and aft.3 We analysis the migrating types of birds, we found that the species numbers and individual quantity of resident exceed winter migrant a lot, about at 80% level, which embody the characteristics of wintering birds composition in northeast China.4, The diameters at tree breast height (DBH) of trees that birds feed on change significantly for 12 years fore-and-aft (P<0.01), which is consistent with the significant changes (P<0.01)of DBH in habitat. The species diversity of tree that birds feed on does not change significantly between 12 years fore-and-aft.5 We analysis the feeding niche breadth of 7 species, the variables include feeding methods, height of feeding parts, level and vertical position of coronal layer, base matter that birds feed on, the species of trees that birds feed on. The feeding niche breadth does not change significantly among 7 species (P>0.01).6 The phenomenon of wintering birds gathering is significant, the population of Long-tailed Tit (Aegithalos caudatus). Dusky Thrush (Turdus naumanni),Common Magpie (Pica pica), Bohemian Waxwing (Bombycilla garrulus), Grey-faced Woodpecker (Picus canus) mainly consists of single species, and the average population size is 6.26 individuals (1989-1990) and 7.44 individuals (2001-2002), the mixed species population mainly consists of Great Tit (Parus major), Marsh Tit (Parus palustris), Eurasian Nuthatdch (Sitta europaed), the average species number is about 3, average number is 7.4 individuals. The number of mixed species population is twice as many as single species population.7 The encountering probability of birds is 0.8195 during the period from 1989 to 1990 and 0.8487 during the period from 2001 to 2002.The aim of our investigation is to probe into the characteristics andchanging trends of wintering birds community structure of mountainous secondary broadleaf forest, and provide scientific foundation for studying the role wintering birds community in ecosystem and the relation with environment.