Description
Summary:As the largest in the world the Taimyr population of wild reindeer displays pronounced seasonal migrations from forest zone to tundra for fawning in spring and return motion in fall. These motions are characterized with dynamics varying from year to year. Evidences of experience suggest that migration course cannot yet be interrupted or curtailed with artificial constructions or anthropogenic disturbance. By results of long-term observations carried out by one of the authors during 20 years, migration timing and speed were related to current ambient temperature and varied from year to year. As foreseen temperature rise happens more intensively inArcticthan upon an average through the Planet and is higher overland than it is over ocean it must apparently exert influence on the pattern of reindeer migrations. We hold that this phenomenon consists with changes in migration activity for recent decades and manifests increasing all-year-round separate reindeer groups presence in tundra. Some of these groups are registered and presented on the skeleton map. In the light of current climatic trend the ecological mechanism of migrations decrease should be grounded on reindeer bioenergetics and derived from ecological function of their migrations. Energy expenditures for far movements are getting less appropriate and the proportion of total heads staying in tundra zone all-year-round will increase. Available bioenergetics parameters and the simple model let to make a prediction. In the end we propose some preventive conservation arrangements to secure the mass heads of wild reindeer staying in tundra against adverse factors, mainly pending anthropogenic. Обитающая на Таймыре популяция диких северных оленей характеризуется четко выраженными сезонными миграциями, динамика которых варьирует от года к году. На основе многолетних полевых наблюдений показана зависимость начального времени и скорости сезонных миграций от текущей приземной температуры воздуха. Рассмотрено влияние на миграции прогнозируемых климатических изменений, приводится картосхема отмечаемых изменений в миграционной активности популяции за последние десятилетия. В свете наблюдаемой тенденции обоснованы экологические причины сокращения миграций оленей с позиций биоэнергетики. Предлагаются превентивные природоохранные меры, призванные обезопасить поголовье оленей в тундровой зоне от неблагоприятных, прежде всего антропогенных факторов.