贺兰山马鹿冬季食性分析

Winter Food-habits of Red Deer (Cervus elaphus alxaicus) in Helan Mountains,China

2003年11月—2004年2月在宁夏贺兰山国家级自然保护区和内蒙古贺兰山国家级自然保护区,利用粪便显微组织学分析技术结合野外啃食调查对马鹿阿拉善亚种(Cervus elaphus alxaicus)冬季食性进行了研究。从7个沟系中一共收集了219堆马鹿粪便中捡拾粪粒,组成14个复合样本进行分析,其结果表明,灰榆(27.37%)、山杨(11.75%)、蒙古扁桃(9.83%)、金露梅(8.12%)、锦鸡儿(6.52%)等植物的当年枝和落叶以及禾本科草本植物(7.51%)是马鹿冬季主要食物,其中灰榆为大宗食物,针叶树种(杜松、油松、青海云杉)和其他草本植物所占比例均较小。马鹿对灰榆、山杨、蒙古扁桃、金露梅、锦鸡儿和杜松有正选择性;而对禾本科草本植物、油松和青海云杉有负选择性。马鹿对它们选择性的强弱顺序为:山杨>杜松>锦鸡儿>蒙古扁桃>金露梅>灰榆>禾本科草本植物>油松>青海云杉。马鹿取食乔木36.8%、灌木44.7%、禾本科草本植物8.0%和非禾本科草本植物10.5%,这4类植物的利用性与可利用性存在极显著差异,乔木和灌木的利用性高于可利用性;禾本科草本植物和非禾本科草本植物的利用性低于可利用性,说明马鹿的食物以木本植物为主,草本植物为辅。Spearman相关分析得出马鹿对食物的选择性与水分、灰分、粗蛋白、粗脂肪、粗纤维和无氮浸出物之间无明显的相关关系。被啃食植物中粗蛋白含量较高,蛋白质不是越冬马鹿的限制因子,而能量可能是影响冬季马鹿采食较为关键的因子。马鹿冬季采食策略主要是以最小的能量消耗获取最大的能量收益。

Winter diet composition, selectivity and foraging strategy of red deer （ Cervus elaphus alxaicus ） was studied with a microhistological analysis technique, using faeces and food in the stomach in combination with field investigations from November 2003 to February 2004 in Helan Mountains between Ningxia Muslem Municipality and Inner Mongolia Municipality. We collected 219 faeces pellets from red deer, which formed 14 composite samples. The results showed that Ulmus pumila , Populus davidiana , Prunus monglica , Dasiphora spp., Graminoids （Stipa spp., Poa spp. ） and Caragana spp. were staples of the red deer. The percentages of the above items in the diet were 27.37%, 11.75%, 9.83%, 8.12%, 7.51% and 6.52% respectively. The red deer had positive selectivity for Ulmus pumila, Populus davidiana, Prunus monglica, Dasiphora spp., Caragana spp. and Juniperus rigida, and negative selectivity for Graminoids （Stipa spp., Poa spp. ）, Pinus tabulaeformis and Pinus crassifolia. Their preference order was as follows： Populus davidiana 〉 Juniperus rigida 〉 Caragana spp. 〉 Prunus monglica 〉 Dasiphora spp. 〉 Ulmus pum//a 〉 Graminoids 〉 Pinus tabulaeformis 〉 Pinus crassifolia. The results of spearman correlative analysis has show that the food selectivities of red deer did not correlate with water, crude ashes, crude protein, crude fat, crude fibre and nitrogen-free extract. The crude protein percentage in the nutritional composition of browsed plants, was sufficient for the red deer, but energy expenditure may be a more critical factor for the wintering red deer. To obtain maximum energy input with minimum energy output is the foraging strategy of the red deer in winter.