Guild structure of forest breeding bird community in Nonggang Nature Reserve of Guangxi

Surveys about the breeding bird guild structure in karst forest of Nonggang Nature Reserve, Guangxi Zhuang Autonomous Region, were conducted successively in May-July 2010, 2011 and 2012. The feeding modes, foraging strata and foraging heights of 44 breeding bird species were analyzed by clustering and principal component method. The results indicated that the avian community could be divided into 6 guilds, including ground feeding guild, lower feeding guild, upper feeding guild, multilayer feeding guild, trunk feeding guild and air strike guild. Depending on the vegetation structure of Nonggang karst forest and feeding habits, middle layer, lower layer and multilayer feeding guilds were dominant in the karst monsoon forest. Data suggests that the birds tried to alleviate competition pressures by increasing niche breadth, so multilayer feeding guild was formed.