浙江五峙山列岛黄嘴白鹭的巢位选择研究

黄嘴白鹭(Egretta eulophotes)是全球性受威胁鸟类。2005年7月,我们在浙江五峙山列岛对黄嘴白鹭的巢位选择进行了研究,共测量了74个巢。研究发现,在0.99hm2的馒头山小岛上,黄嘴白鹭的巢呈聚集性分布,平均巢间距为119.6cm,最小巢间距为15cm。黄嘴白鹭对巢位具有明显的选择性,优先选择在灌丛,尤其是那些相对较高的灌丛(高于50cm)下营巢,其次是较低的灌木(低于64cm)内部和草丛上。多数巢存在遮蔽物。避风和遮荫是黄嘴白鹭巢位选择的主要要求。台风是决定五峙山列岛黄嘴白鹭巢位选择的最主要因素,而高灌木的数量直接影响五峙山列岛黄嘴白鹭的繁殖成功和今后的资源状况。

Nest selection of Chinese egret (Egretta eulophotes) in Wuzhishan Archipelago, Zhejiang

The Chinese egret(Egretta eulophotes)is a globally endangered species.During July in 2005,we studied nest selection of Chinese egret in Wuzhishan Archipelago of Zhejiang Province.A total of 74 nests were recorded.The results showed that the nests of Chinese egrets were aggregated in space on Mantoushan Islet(0.99 hm2)with an average distance of 119.6 cm between nests,and a minimum of 15 cm.Chinese egrets showed significant preference for the ground under shrubs as their nest site,especially below shrubs higher than 50 cm,followed by sites inside shrubs lower than 64 cm and on top of tussocks.Most nests were sheltered.When selecting nest sites,Chinese egrets chose sites that maximized shelter from typhoon and di-rect sun.Typhoon exposure was the most important factor influencing nest site selection of Chinese egrets,while the amount of high shrubs determined the reproductive success and the future status of Chinese egrets in Wuzhishan Archipelago Nature Reserve.