Food Storing Behaviour of Willow Tit Parus montanus

Abstract

Food storing behaviour in the Willow Tit Parus montanus restrictus was studied in Sugadaira Hight, Central Japan, 1974 to 1986. In the breeding season, larvae and adult insects occupied 88% of the total diet. Seeds increased in the diet from September to become chief food in autumn to winter, and about 70% of food consumed in winter was those stored in the autumn. During breeding season, food storing occurred only infrequently. The behaviour was most frequent in autumn, and 86.3% of the total food taken in October was stored. Food was mostly (99.3%) stored in trees and 53.9% of which were coniferous trees. Willow Tit preferred trees with exfoliately bark, such as red pine Pinus densiflora, oak Quercus mongolica, birch Betula Ermanii, etc., and avoided smooth barked trees, such as beech Fugus crenata, dogwood Cornus controversa, etc. The 67.9% of stored food was found in the interstice of bark, and others were stored in the crevice of a broken stick, or opened pine cone.
In the study area, three families of the Willow Tit formed a compound flock in August. Each member stored food widely in their flock range, without particular concentration. However, strict dominance order occurred in the flock, but with no correlation between order of dominance and frequency of food storing. The duration of store was short, 74% of stored food having been removed within 6 days from the day of storing. Often, however, a stored food was removed and re-stored at different site and the food stored in autumn, was consumed during winter as the main food. Some discussions were given about particularities in the food storing behaviour of the Willow Tit.