东方白鹳幼鸟在繁殖区生境选择的跟踪研究

鸟类的生境选择与气候、栖息地及人为干扰有关,而在不同生活史阶段因其自身需求及环境资源的变化也将出现差异。为明晰该一过程和规律,基于东方白鹳(Ciconia boyciana)在三江平原的卫星跟踪数据,按照时间序列通过核密度分析法(95%水平)得到繁殖季节(7—10月)跟踪个体的活动范围变化,据此将该时期细分为在巢期与离巢游荡期两个阶段,在巢期活动范围窄且高度聚集于单一区域,而离巢游荡期活动范围分散于三江平原东部和北部的多个地点。后采用Maxent模型对两个阶段的适宜生境空间分布及其主要因子进行评估发现,在巢期和离巢期主要影响因子分别为(在巢期贡献率/离巢期贡献率):土地覆被类型(11.8%/30.6%)、水体(23.8%/31.2%)、相对湿度(8.1%/15.5%)、草本沼泽(28.6%/3.2%)及相对风速(13.2%/2.1%);离巢期的较适宜生境(0.4—1)比在巢期扩大近两倍,且对人为活动表现出更强的耐受性。本研究结果可用于东方白鹳及其他迁徙鸟类繁殖相关的动态保护与有效综合管理。

Quantifying habitat selection of Oriental White Stork fledgling in their breeding area based on satellite tracking data

Habitat selection of birds is related to climate, habitat and human disturbance, and there are differences in their life periods due to changes in needs and environmental resources. In order to clarify the process, in Sanjiang Plain, we analyzed the oriental white stork fledglings'' movements by fixed Kernel Home Range method (95% level) during July to October based on satellite tracking data. Then subdivided the breeding season into two periods: Wandering around nests and after leaving nests. During the early period, the activity range is narrow and highly concentrated in a single area, while during the later period, they scattered and wandering in multiple areas in the eastern part of the Sanjiang Plain. Then we used Maxent model to evaluate the variability in habitat suitability including factors'' influences. The results showed that the Percent contribution of factors such as Land cover type(11.8%/30.6%), Water (23.8%/31.2%), Humidity(8.1%/15.5%), Meadow(28.6%/3.2%) and Wind speed(13.2%/2.1%) are different in two periods, and the more suitable habitats area in the later period (0.5-1) is doubled in the early period and showed greater tolerance to human disturbance. Our study could be used for dynamic protection and effective integrated management of Oriental White Stork and other migratory species.