关键词: 生态位分化, 栖息地选择, 日活动节律, 黑麂, 小麂

Abstract:

Niche differentiation is an important ecological theory in explaining the coexistence of species. Schonenr believes that the spatial dimension has the highest influence on the formation of niche differences, followed by the nutritional dimension, and the time dimension is the last to be activated. To verify this hypothesis, we used the kilometer grid method to place 52 infrared cameras in the Longtangshan area of the Qingliangfeng National Nature Reserve in Zhejiang from December 2018 to November 2019. We monitored the populations of sympatric black muntjac and Reeves’ muntjac that have similar feeding habits. The average capture rate was calculated to analyze the differences in the species’ selection of vegetation type, altitude, slope position, and distance from water sources in different seasons. The nuclear density estimation method was used to analyze the daily activity rhythm and the degree of overlap in the activities of the two species. The results indicate that black muntjac and Reeves’ muntjac have different choices in spatial niche: black muntjac prefers mixed broadleaf-conifer forest, primarily inhabiting areas with high altitude between 1 301 - 1 500 m and avoiding areas with low altitudes and valleys. Activities of the black muntjac are frequent in areas closer to water sources. The Reeves’ muntjac prefers deciduous broadleaved forests, mainly inhabits areas with an elevation of 901 - 1 100 m, prefers mid-slope positions, avoids valleys, and has no obvious tendency towards choosing water sources. The black muntjac and the Reeves’ muntjac are both diurnal animals with morning and twilight activities, and the overlap of their daily activity rhythms throughout the year is relatively high (Δ4 = 0.86), and only lower in winter (Δ1 = 0.65). The above results support the hypothesis of Schonenr. First, spatial dimension has a greater impact on species niche differentiation than the temporal dimension. The black muntjac and Reeves’ muntjac in the Longtang Mountain area mainly choose different habitats to avoid overlapping territories and reduce the competition between both species. Secondly, there are seasonal differences in this model. In winter, due to the reduction of available resources, competition intensifies. Both species adjust their rhythm of daily activities to increase the degree of temporal niche differentiation in order to achieve coexistence in the same region.

Key words: Niche differentiation, Habitat selection, Daily activity rhythm, Black muntjac (Muntiacus crinifrons), Reeves’ muntjac (Muntiacus reevesi)