龙凤保护区普通鸬鹚巢特征与巢址选择

巢址选择作为鸟类繁殖的重要环节，是动物生态学关注的热点问题。为探究中等体型湿地鸟类普通鸬鹚的巢址选择偏好及主要影响因子，2019年4—10月运用秩和检验、主成分分析等方法对黑龙江龙凤保护区内普通鸬鹚巢特征、巢址特征、巢址选择进行了分析。结果表明：(1)普通鸬鹚偏好选择巢树乔木相对较矮(P<0.05)、周围灌木相对较矮(P<0.01)、植被盖度较低(P<0.01)、人为干扰距离较远(P<0.01)、距水面距离较远(P<0.05)的区域筑巢；(2)影响普通鸬鹚巢址选择的因子为隐蔽因子(20.634%)、巢稳定因子和干扰因子(27.614%)、植被因子(13.901%)、水因子(5.782%)和巢忠诚度(5.069%)。进一步分析表明：(1)普通鸬鹚倾向选择粗细适中的巢材，巢材来源于优势植被，巢深随纬度增高而增大；(2)巢区植被特征符合普通鸬鹚对能量支配的权衡，巢区粪便对该特征有强化作用。基于上述结果，建议龙凤保护区在巢区内加种高大乔木。

Nests characteristics and nest-site selection of Common Cormorant in Longfeng Reserve, China

Nest site selection, as an important part of bird breeding, is a hot issue in animal ecology. In order to explore the nest site selection preference and the main influencing factors of Common Cormorant, a medium-sized wetland bird, we analyzed the nest characteristics, nest site characteristics and nest site selection of Common Cormorant in Longfeng Reserve of Heilongjiang Province from April to October in 2019 by Mann-Whitney U test and principal component analysis. The results showed that: (1) Common Cormorants preferred to nest in the areas where the trees were relatively short (P<0.05), surrounding shrubs were relatively short (P<0.01), vegetation coverage was low (P<0.01), the distance from human disturbance was far (P<0.01), and the distance from water surface was far (P<0.05). (2) The influencing factors of nest site selection were concealment factor (20.634%), nest stability factor and disturbance factor (27.614%), vegetation factor (13.901%), water factor (5.782%) and nest loyalty factor (5.069%). Further analysis showed that: (1) The Common Cormorants tended to choose nest materials of moderate thickness, which came from dominant vegetation, and nest depth increased with increasing latitude. (2) The characteristics of Common Cormorants nest vegetation were consistent with the trade-offs of energy domination, and the feces in nest enhanced the characteristics. Based on above results, it is suggested that the tall trees should be planted in the nest area of Longfeng Reserve.