Семенов-Тян-Шанский О.И. Экология тетеревиных птиц. Москва, 1959.

Semenov-Han-Shansky, Oleg ON ECOLOGY OF TETRAONIDS S u mm a r y The present study was carried out in Lapland Reserve (district of Murmansk) in 1930— 1951, and partly in Petshora-Ylytsh Reserve (Republic of Komi) , in 1952— 1958; both Reserves are situated in taiga region. Chapter 1 deals with the distribution of Tetraonids in Murmansk district. Capercaillie and Hasel grouse areas are limited to the northern range of forests. The distribution of Blackgame, owing to progress of agriculture and wood-cutting, greatly increased in last decades; being limited up to 1900 to the south coast of Imandra Lake, its area now reaches Kola fiord. Willow grouse is widely distributed on the whole district, but Rock ptarmigan is restricted mainly to the tundra region of mountain ranges. In Ch. II plant cover and some physical-geography features of Lapland Reserve are described. In Ch. Ill habits of our Tetraonids and their seasonal changes are described. In tables 1—5 some phenologic data are recorded. Food habits are described in Ch. IV. In tables 8—21 food items found in crops are recorded for months separately. They are classified as follows: I — browse food, forming the bulk of winter diet; II — ever­ green plants; III — leaves of deciduous plants; IV — blossoms; V — ber­ ries; VI — capsules and seeds; VII — mushrooms, mosses and lichens; VIII — animal food; IX — grit. For each species three tables are given, in the first — frequency of occurrence of different food items in adult birds (per cent) is recorded, in the second — the approximate quantity of them (per m ille); in the third — frequency and quantity of corres­ ponding food items of juvenile birds. In summer all grouse are mostly herbivorous and their food habits have much in common. Animal food (mainly insects) is consumed chiefly by juveniles. In winter all grouse forage on trees and each species has its own specific diet. The brow­ sing season is the longest in Capercaillie (0,56 of year), then follow 301