凉水自然保护区松鼠巢址选择的特征

2006 年6 月11 日至9 月27 日和2007 年8 月14 日至9 月21 日采用样线法,并结合定位观察的方法在凉水国家级自然保护区对松鼠的巢址选择进行了定量研究,共获取107 个巢样方和230 个对照样方。对每个样方分别测定了12 个巢树参数和7 个环境参数。统计分析结果表明,松鼠仅在针叶树上营巢,59.8 ± 4. 7% 的巢建于红松上,但对枝叶比红松更为浓密的云杉和臭冷杉有显著的选择性,而且显著倾向于在以云杉、臭冷杉为优势树种的生境中营巢。松鼠选择比较高大(树高21.5 ± 0.4 m)、活动通道比较多(3.6 ±0.1)的树营巢,巢树周围的树木密度(169 ± 4 株/ hm² )和多样性(辛普森指数0.51 ± 0.01)显著高于对照样方。巢址生境多位于南向的中、下坡位。巢址高12.4 ± 0.4 m,紧贴树干,多朝南。红松树上的巢多建于树冠的中下部,云杉和臭冷杉树上的巢多建于树冠的上部。松鼠巢对包括道路在内的林隙没有显著的回避。

Nest-site selection by the Eurasian red squirrels(Sciurus vulgaris)in Liangshui Nature Reserve

Nests are important structures for reproduction and survival for tree squirrels. Some investigations showed that the Eurasian red squirrel (Sciurus vulgaris)depended on Korean pine (Pinus koraiensis) for food. This paper performed a research on nest-site selection of the Eurasian red squirrel in Liangshui National Nature Reserve from June 11th to September 27, 2006 and August 14th to September 21th, 2007. The data of nest-sites (n = 107) were obtained in comparison with random sites (n = 230). Twelve nest tree characteristics and 7 habitat characteristics were respectively measured at each site. Nests in this research were found that in four different conifer species. The statistical analysis showed that despite 59.8 ±4.7% nests were built in Korean
pine,squirrels significantly selected needle fir (Picea) and spruce (Abies nephrolepis) for habitat as nest sites. Nests were built close to the main trunk at a height of 12.4 ± 0.4 m (ratio of nest to tree height = 0.60 ± 0.02) in upper canopy of needle fir and spruce,and in lower canopy of Korean pine. Nest trees were larger (tree height 21.5 ± 0.4 m) and had more access routes (3.6 ± 0.1) than random trees. Nests were built most frequently in middle,lower slope and towards the south. The density (169 ± 4 trees / hm² )and diversity (Simpson index 0.51± 0. 01) of trees surrounding nests apparently was important for Sciurus vulgaris to build nests. Distance to canopy opening (including road) didn’t influence the nest-sites selection by Sciurus vulgaris.