基于卫星跟踪个体的越冬灰鹤栖息地选择

Habitat selection of overwintering common crane (Grus grus) based on individuals tracking by satellite technology

开展物种栖息地选择研究,对保护濒危动物和其生境具有重要意义。于2014年冬季,在贵州威宁草海保护区利用卫星跟踪技术和随机森林模型对7只越冬灰鹤(Grus grus)进行了日间栖息地选择研究。结果表明:灰鹤对栖息地(距夜栖地、林地、草地、沼泽、水域和耕地的距离)、人为干扰(距居民点、主干道、村道)、海拔等环境因子存在明显的选择性(P<0.05),而对坡度未表现出选择性(P>0.05);随机森林模型表明,距主干道距离、距夜栖地距离、距居民点距离和距草地距离对灰鹤的栖息地选择过程影响最大;综合来看,灰鹤在日间喜好在靠近水源(858.86±29.39 m)和夜栖地(1914.70±59.14 m)、并远离居民点(312.87±10.28 m)的区域活动;在距主干道距离和距村道距离两个因子上,灰鹤活动点均显著小于随机点,这可能表明灰鹤在利用耕地作为主要觅食地时,被迫适应道路交通带来的较大干扰;城镇的快速扩张以及道路修建是草海及周边区域威胁灰鹤生存的主要因素。

Understanding species habitat selection is of great significance for the protection of endangered animals and their habitats.In the winter of 2014,we investigated the daytime habitat selection of seven overwintering common cranes(Grus grus)by satellite tracking technology and a random forest model at Weining Caohai Nature Reserve in Guizhou Province.The results showed that the common crane had obvious selectivity to habitats(distances from nocturnal roosting site,woodland,grassland,marsh,open water and cropland),human disturbance(distances to residential areas,main roads,village roads),and elevation(P<0.05),but not to slope(P>0.05).The results of the random forest regression modeling showed that the distances from main road,nocturnal roosting site,residential areas and grassland had the greatest impacts on their habitat selection.Common cranes preferred areas near water source(858.86±29.39 m)and nocturnal roosting site(1914.70±59.14 m),and away from residential areas(312.87±10.28 m)during the daytime.In terms of the distance from the main road and the village road,the number of activity points of common cranes was significantly smaller than that of random points,indicating that common cranes may be forced to adapt to disturbances by road traffic when using cropland as their main feeding sites.The rapid urban/town expansion and road construction were the main factors threatening the survival of common cranes in Caohai and surrounding areas.