大鸨求偶场的选择

20 0 0年和 2 0 0 1年的 4～ 7月 ,在吉林省西北部和内蒙古东北部草原地带 ,采用观察法及样方法对大鸨 (Otis tardadybowskii)的求偶炫耀行为及求偶场选择进行了研究。结果表明 :大鸨具有集群炫耀的特点 ,雄鸨一天之中有两个求偶炫耀高峰期 ,上午为 7:0 0～ 9:0 0 ,下午为 16 :0 0～ 17:30 ,下午的炫耀强度较早晨略弱。求偶场选择在坡度平缓、视野开阔的草原岗坡的下坡腰和坡底 ,而且是在土质松软、土壤颗粒较细的地方。草原火烧对其求偶场选择具有一定影响。在火烧地 ,高度为 2 0～ 30 cm植物所占比例、植物种类数、植被盖度、植物均高和线叶菊密度是主要因子 ;在非火烧地 ,枯草比例和枯草厚度是重要因子 ;综合来看 ,在植被结构上 ,其求偶场主要选择在植物种类丰富、植株相对较高及裸地比例和地面枯草厚度较小处

Lek field selection of great bustard

We studied the display behaviors and lek field selection of Great Bustard on the grassland of northwest in Jilin province and northeast Inner Mongolia during April to July in 2000 to 2001.We found that Great Bustard proffered to lek. Great Bustard choose their lek fields below the middle hills or at the feet of hills with smooth slope, soft soil and large landscape. We studied the fields of grassland, unburned grassland, plant numbers and average height, species richness and the density of Filifolium sibiricum, percentages and thickness of the hay. Results show that Great Bustard proffers to lek in the fields with rich plant species, higher plant, lower percentages of bare ground and lower thickness of hay.