Spatial structure of populations of Marmota himalayana Hodgson (1841) in Nepal. Prostranstvennaya strouktoura popoulyatsii gimala?skogo sourka Marmota himalayana Hodgson (1841) v Nepale. [Structure spatiales des populations de Marmota himalayana Hodgson (1841) au Népal].

Résumé

On the base of observations in Nepal (Central Himalayas, massive Manaslu) in 2003-2004 four hierarchic ranks of Himalayan marmot population structure were determined (from top to bottom): 1) geographic population; 2) local population; 3) settlement (colony); 4) family site.1. Geographic population. The whole population of Himalayan marmot in Nepal forms geographic population isolated from the neighboring Tibet. Geographic population occupies area about 1 million ha. Number of population within Nepal boundaries we estimate as 100,000-500,000 animals. In the Hymalayas area of the geographic population roughly coincides with the borders of subalpine and alpine mountain zones from the upper forest line to snow line. 2. Local populations of Himalayan marmot in Nepal are isolated from each other by mountain ridges almost insuperable for marmots: for example, local population "Manaslu" and neighboring population "Anapurna" are separated by iced mountain ridges. Local populations inhabit mainly terraces above flood-lands of river heads and border relief areas, first of all - superficial cones. 3. Settlements. Local populations consist of settlements. Their area runs up to 50 ha. Settlement may comprise 5-30 families. Within local populations settlements are separated by natural barriers (rivers beds, new moraines, rocky sites) and anthropogenic barriers (human settlements and communications network, vegetable gardens, cattle-pens). 4. Famüy sites. Family site borders can be remote from each other or can partly overlap. Distribution of family sites retlects landscape features of the settlement in general. Number of burrow entrances per a family site varies from 20 to 27. Mean area of a family site is 0.5-1.7 ha. General type of spatial structure of Himalayan marmot population does not differ basically from the spatial structure of populations of other mountain marmot species, like M. baibacina or M. caudata, and does not contlict the classification suggested earlier by D.I. Bibikov (1989).