汉江流域鸭科鸟类的调查

Surveys of Anatidae Birds along Hanjiang River

1983～2005年的22年里，在汉江流域记录到鸭科鸟类20种，其中10种是住2005年冬季调查中发现。亦麻鸭和绿头鸭为优势种，分别占统计鸟总数的31．24％和19．71％。其密度分别是85．90／km和53．11／km。鸭科鸟住汉江栖息河段共同具有5个特点：河面宽阔；水流缓慢；有沙石滩；没有山脉；没有人为干扰。为预防禽流感，应禁止在有野鸭栖息的河段，放养家鸭。

During 22 years from 1983 to 2005, 20 species of Anatidae birds had been recorded along Hanjiang River. 10 species among them were detected in the survey in the winter of 2005. The Ruddy Shelduck Tadorna ferruginea and Mallard Anas platyrhgnchos were the dominant species, which accounted separately for 31.24% and 19.71% of the total statistics. Their distinctive density was 85.90/km and 53. 10/km. The habitats of these birds had five common characteristics： broad river bed, slow current, sandy beach, no mountain, no human activities. In order to prevent avian influenza, we should prohibit people from breeding domestic ducks in these areas.