藏北繁殖黑颈鹤的巢址特征及觅食地选择

Nest Site Characteristics and Foraging Habitat Selection of Breeding Black-necked Cranes in Bange,Tibet Autonomous Region,China

2006年4—6月,利用样点法和扫描取样法在藏北观测了繁殖黑颈鹤(Grus nigricollis)的巢址特征和觅食地选择。主成分分析结果表明:岛屿规模及状况、安全和筑巢需求以及巢的位置是黑颈鹤巢址的主要特征,表现了89%的方差信息。Bonferroni Z检验表明,黑颈鹤对不同觅食地的选择性存在差异:浅水泥炭地的选择性最高(1.375),其次是青藏苔草草甸(-0.125)、杂草盐生草甸(-0.750),对牧地的选择性最低(-1.000)。Friedman非参数多重比较结果表明:浅水泥炭地的选择性与牧地、杂草盐生草甸和青藏苔草草甸3种类型的觅食地均有统计学差异(P<0.05);青藏苔草草甸与牧地生境有统计学差异(P<0.05),但与杂草盐生草甸没有统计学差异(P>0.05);杂草盐生草甸与牧地没有统计学差异(P>0.05)。适宜的巢址是影响繁殖期间黑颈鹤分布的主要因素。

A study was conducted to study the characteristics of nest sites built on an island and foraging habitat selection of breeding Black-necked Cranes（Grus nigricollis） in Northern Tibet by point sampling and scan sampling during April and July in 2006.Result of principle component analysis indicates that the area and status of the island,safety,demand for building nests,and nest location in the island are the main nest characteristics,which include 89% of information about variance of all the ecological factors.There are differences in foraging habitats by the Bonferroni interval.Peatland with shallow water is their favorite foraging habitat,with a high selectivity（1.375）,followed by Carex moorcroftii meadow（-0.125）,salt meadow（-0.750） and pasture（-1.000）.Result of Friedman＇s two-way nonparametric analysis of variance shows that there are significant differences in selectivity between peatland with shallow water and other three habitats and between C.moorcroftii meadow and pasture（P 0.05）,but there are no significant differences between C.moorcroftii meadow and salt meadow and between pasture and salt meadow（P 0.05）.The suitable nest is the main factor influencing the population distribution of Black-necked Crane during breeding.