1　鸟类调查的目的鸟类在维护生态平衡、消灭农林害虫、美化人类生活等方面都起着重要的作用。这是大自然赐予人类的宝贵财富,是我们的朋友。但是近年来,随着环境的严重污染,森林面积的缩小,鸟类的生存已受到严重的威胁,其种群数量正在日益减少,一些珍稀鸟类甚至已到了绝迹的边 The purpose of a bird survey Birds in the maintenance of ecological balance, the elimination of agricultural and forestry pests, landscaping and other human beings play an important role. This is the precious treasure that nature has given to mankind and it is our friend. However, in recent years, with the serious pollution of the environment and the shrinking of the forest area, the survival of birds has been seriously threatened. The population of these birds is decreasing day by day. Some rare birds have even reached the edge of extinction