陕西红碱淖普通燕鸥和鸥嘴噪鸥的繁殖生态比较

Comparative Studies on Breeding Ecology of Sterna hirundo and Gelochelidon nilotica in Hongjiannao Lake,Shaanxi Province

2009年4～7月,采用定点观察法和逐巢清点法,对陕西省红碱淖地区普通燕鸥(Sterna hirundo)和鸥嘴噪鸥(Gelochelidon nilotica)的繁殖生态进行了比较研究。结果表明,两者都是4月末迁至红碱淖,并于5月中旬进入繁殖期。普通燕鸥和鸥嘴噪鸥都选择在湖心岛上营巢,普通燕鸥巢址沿岛边缘四周呈线状分布,而鸥嘴噪鸥位于岛中央向外扩散呈块状分布。对食物调查发现,两者在食物资源利用上存在部分生态位分离。巢址分布格局差异性和食物资源利用生态位部分分离是两者能在同一领域共存的主要原因。对雏鸟的体重等形态参数进行Gompertz曲线方程拟合,结果表明,两种雏鸟生长状况的差异性从另一面也可以反应二者种间竞争压力的缓和。另外,从一定的角度分析了两者与遗鸥(Larus relictus)的伴生关系。

The breeding ecology of Common Tern （Sterna hirundo） and Gull-billed Tern （Gelochelidon nilotica） were studied in Hongjiannao Lake of Shaanxi Province from April to July of 2009 by direct observation and by counting the nests. Both of them arrived at Hongjiannao Lake in late April and bred in the middle of May. Both species built their hest at the islands in Hongjiannao Lake,but the nest-sites of S. hirundo located in the margin area of the islands in linear patterns,and the nest-sites of G. nilotica were built in the center region in a patch patterns. Food items of the two species were partially separated. Therefore,the separations in nest-sites and food items were regarded as the major reasons for the two identical bird breeding in the same area. The growth curves of the nestling body mass of the two species matched with the description of Gompertz equation and the difference in growth rate of the two birds might reduce the interspecies competition.