喜馬拉雅林鴞（Strix newarensis）繁殖生態學：繁殖、食性與捕食行為描述

Breeding Ecology, Food Habit and Hunting Behavior of the Himalaya Wood Owl Strix newarensis

本研究主要描述稀有猛禽喜馬拉雅林鴞（Strix newarensis）的繁殖、繁殖期間的食性及捕食行為。於1996年3月、2003年2月與2004年3月，在海拔900-2,600m間的闊葉林內發現3處喜馬拉雅林鴞巢位。喜馬拉雅林鴞每巢產卵1-2枚。幼鴞停留在巢中的時間是25.3±2.5天。離巢後會棲息於巢區直徑1,000m之範圍中長達4-5個月。繁殖期間幼鴞的食物主要是哺乳類，以大型鼯鼠類提供的生物量最多（81.8%）。在繁殖的不同階段，雌雄親鳥有角色上的分工，雌鴞在幼鴞2週大以前，以孵蛋、幫幼鴞保暖、處理食物，或是待在巢區附近警戒為主，2週後才會離巢較遠。雄鴞在幼鴞2週大以前主要提供食物，平時則在巢樹附近守衛。育雛期間雌鴞供應的生物量比雄鴞多，而且雌鴞抓大型獵物的比例較雄鴞高。研究期間，總共觀察到喜馬拉雅林鴞成鳥在低處定點守候、高處尾隨追擊與洞口守候等3種捕食行為。 We found three nests of the Himalaya wood owl (Strix newarensis) in deciduous forests in the Central Mountain Ranges of Taiwan at the elevations of 900-2,600m, March 1996, February 2003 and March 2004. Each nest had 1 or 2 eggs. After hatching owlets stayed in the nests for 25.3±2.5 days, and then left the nests but remained in their natal areas (about 1,000m in diameter) for 4-5 months. Male and female owls played different roles in the parental care. Female incubated the eggs, kept owlets warm and manipulated food to feed the owlets for about two weeks after hatching, while male provided food to the female and owlets, and guarded the nest nearby. With increasing in the appetite of the owlets as they rapidly grew, the female left the nest for hunting, and her hunting period and distance became longer and farther with time. During this period both parents provided food for the owlets, but female provided more and larger prey than did by male. The major prey items fed by the parents to the owlets were mammals, of which large flying squirrels was the major food item (81.8%). There were three hunting behaviors of the adult owls: 1) sit and wait at low sites, 2) track and hunt at high sites, and 3) stand at tree holes.