Holarctic Marmots as a factor of Biodiversity.
Rumiantsev V.Yu;, Nikol'skii A.A. & Brandler O.V. eds.,
Abstracts, 3d Conference on Marmots (Cheboksary, Russia, 25-30 August 1997),
Moscow ABF 1997, 216p. : 204-205.


N.K. Zheleznov

Chukotsky Nature Use Department of the North East of Russia, Chukotka, Anadyr, Russia

Blackhat marmots (Marmota camtschatica) in the North East of Asia differ from other subspecies by their large distribution and a complex area structure (Zheleznov, 1988). Although within the area taxonomic status of the kamchatsky marmot has to be specified, nevertheless, in its structure the animal covers several nature zones, where two powerful blocks of marmots' habitats may be marked out. The first block is a great in its territory mountainous country including several mountain ranges and chains - Koriaksky upland in the south of Chukotka. The second one is made up of the northern, central and southern portions of Camchatka. Within the area the marmot habitats are extraordinarily mozaic, but in relation to longitudes they are situated within a small diapason of meridians (in south-east they are limited by 179o35'E, and in west by 156o40' W). As regards to latitudes, the kamchatsky marmot inhabits a large diapason from zero till up 700 m above sea level. If the marmot area is considered from the point of view of landscape division into districts, i.e. taking into account climatic signs, so the marmot area should be noted to embrace sharp continental regions of the North East of Asia, continental, moderate continental and maritime ones, where there are villages along the Bering and Okhotsk seas' coasts. Direct and indirect external factors stipulate the structure of the kamchatsky marmot area and of its population structure. I have analysed environmental factors throughout the marmot area, sight frequency and family density in its habitats, and the analysis snows the animal distribution depending on concrete food conditions, slope expositions, location type of all kinds of holes, presence of predators, their species abundance and on anthropogenic pressure. According to my data the factors affecting directly, such as destruction of holes and marmot skins' harvest in the North East of Asia, are the main ones (Zheleznov, 1988). For example, it happened with a group of geologists, when they destroyed completely a large marmot population on the terraces of the Listvenny creek, a right tributary of the Iomrautvaam in the Koriaksky upland. Another type of direct affection on the population is to trample down plants in habitation hearths by domestic reindeer. That factor is especially typical for populations inhabiting low mountains, where the marmot food stations coincide with those ones of domestic reindeer. It generally occurs in the outlying parts of low mountain systems, on wide plateaux and terraces of large and small rivers and lakes. There are indirect factors influencing on the marmot population status mediatedly - food and protection stations and conditions to hole. Welfare of kamchatsky marmots within their area strictly depends on total affect of all the factors stated above.

Vegetation cover of the area includes a large variety of local plants and of many plant species used by marmots as food. First, it is stipulated by microclimatic conditions, indirectly affecting forage state, food plant species abundance, nutrition ration composition and on the population status as a whole. Usually, a considerable variety of food plants in concrete habitats is a certain indicator of microclimatic and soil conditions in the kamchatsky marmot habitats. Either light or small detritus soils of old river and lake terraces of moraine origin may be attributed to the first group of soil conditions. Small, but powerful accumulated soils of highland terraces belong to the second group. Such soils are typical for gentle slopes of low mountain chains with fine-grained ground forming small banks where marmots arrange their holes, although the animals are quite vulnerable there to birds and other predators. In the areas of the first soil group communities of the marmot populations have traditional forms, structure and picture of hole locations accepted since olden days. They depend on climate, plants and conditions to hole, determined by underlying relief surface. Colomies of such marmot micropopulations are quite stable barring direct or indirect human impact (Zheleznov, 1988). The most steady-going populations of kamchatsky marmots are in the central parts of middle and high mountains, in particular, in the north of the Koriaksky upland - region of the mountains Rzhavaja and Naanknei, and in Kamchatka, along the forest or alpine belts' borders - region of the river Kosyrenka uppers in the Sredinny range, where factors influencing directly are absent, and indirect ones either act poorly or their affection speed is considerably lower, than possibility of such populations to recover their well-being. There is no doubt, marmot settlements included into protection zones, for example, into the Kronotsky reserve, may be considered as the most stable ones, since their status only depends on natural factors. Besides, safe populations of kamchatsky marmots in the North East of Asia occur in discontinuous kurumniks (middle and large stone placers), where due to chemical decay there are surplus of fine-grained ground, good combination of forage, favourable protection stations and conditions to hole. Communities of marmots inhabiting the river Zmeika uppers, surroundings of the Chetkinvaam lake (northern portion of the Koriaksky upland) may serve as an example of such populations. Other part of the area, in particular, the Maino-Pylginsky range, has a high temperature regime of the soil surface due to friable deposits above permafrost, and there is a broken type of long-year-frozen rocks' distribution because of tectonic processes, and thawed waters are situated close to the relief surface. Such areas are extraordinary suitable for holes to be arranged, many food plants grow there and marmot settlements are placed with high density. Combination of these factors with other positive ones makes marmot micropopulation quite successful there.

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