基于卫星跟踪的灰雁秋季活动特征与生境利用研究

营养和能量有效的积累对候鸟能否顺利完成迁徙具有重要意义。2015年8月至10月在内蒙古图牧吉湿地,利用卫星跟踪技术对灰雁的活动特征、生境利用等方面进行了研究,以期阐明灰雁在秋季如何有效积累能量以满足迁徙前的生理需求。我们采用增强型植被指数(EVI)分析了灰雁的生境特征,运用核密度分析法(KDE)计算了日间和夜间活动区面积,以及对不同月份的平均活动距离进行了分析。结果表明,8至10月间,灰雁活动位点的EVI值逐月递减,并且逐渐向南移动,趋向于水域集中,增加了对湖泊的利用,同时减少了对草地的利用;灰雁的活动区面积逐月递增,日间活动区面积大于夜间;灰雁在日间、夜间及平均活动距离均呈递增的趋势,每天凌晨及黄昏都出现较长时间的活动。由于8至10月间气温逐渐降低,从草地中可以获取的潜在食物资源减少,灰雁通过逐渐向水域较为丰富的区域移动,活动区面积逐渐增大,增加活动距离提高食物的获取量等确保获取足够的食物和能量满足迁徙的需求。

Studies on the movement, home range, and habitat use of greylag geese (Anser anser) based on satellite tracking

The accumulation of nutrition and energy is an important factor for the migration of migratory birds. To understand how greylag geese obtain energy to meet the physiological demands of fall migration, we studied the movement, home range and habitat use of graylag geese by using satellite tracking from August to October 2015 in the Tumuji wetland of Inner Mongolia. The enhanced vegetation index (EVI) was used to analyze habitat use, the sizes of the day and night home ranges were determined using kernel density estimation (KDE), and the average activity distances in different months were analyzed. The EVI of the locations of the greylag geese decreased from August to October, the geese gradually dispersed southward and concentrated around the area with abundant water, and they preferred the lakes to the grassland. The home range size of the geese increased from August to October and the home range size was larger in daytime than at night. The movement distances of greylag geese were higher during the day, especially for the peak of movement before dawn and at dusk. Because the temperature decreased gradually from August to October, the potential food resources in grassland declined, and greylag geese tended to occupy the areas with more abundant water, which gradually increased both the home range size and the movement distances, thus enabling the geese to efficiently obtain sufficient nutrition and energy to meet the physiological demand of fall migration.