Abstract
Since 1983 Hazel Grouses (Tetrastes bonasia) have been reared and kept in captivity for use in studies on biology and captive breeding in the Obihiro University and Veterinary Medicine, Hokkaido. Birds fed on the basic diets (a mixture of commercial poultry rations, pet food and fish meal with vegetables; in addition, mush for quail, commercial chick feed and boiled yolk were added for chicks) showed similar growth and seasonal changes in body weight in natural conditions. However, there are some problems connected with the reproducing eggs and rearing birds; 1) difficulty in collection eggs in the field, 2) birds bred by artificial incubation and rearing do not show escape behaviour from peoples, 3) although rearing chicks by mother bird is better than artificial rearing, large aviary is required for the former method of rearing, 4) gizzard developed poorly in birds fed on artificial diets compared with wild birds, 5) careful management of aviary is required to prevent disease such as aspergillosis. In addition, assessment of habitat conditions such as food conditions, hiding places and nest sites before releasing birds. The growth of the Hazel Grouse populations is not expected by releasing bird bred in captivity and habitat improvement is the important procedure to maintain the population level in Hokkaido.
