Kullberg C
Department of Zoology, Stockholm University
Anim Behav. 1998 Jul;56(1):227-33. doi: 10.1006/anbe.1998.0765.
Recently, some empirical studies have shown an effect of body mass on take-off ability in birds, supporting the theory that birds with increased fat loads face a greater predation risk. Small wintering birds accumulate fat reserves of about 10% of their fat-free body mass during the day to survive long, cold, winter nights. Theoretically, mass-dependent predation risk could be an important factor affecting their daily foraging routines. I studied the take-off ability of wintering willow tits, Parus montanus, in relation to their fat load. Willow tits were on average 7.7% heavier at dusk than at dawn but there was no measurable effect of body mass on take-off ability. The results indicate that the relatively small fat loads accumulated during a day by willow tits do not increase the risk of predation as a consequence of reduced take-off ability. Copyright 1998 The Association for the Study of Animal Behaviour.
最近，一些实证研究表明体重对鸟类的起飞能力有影响，这支持了脂肪负荷增加的鸟类面临更大捕食风险的理论。小型越冬鸟类在白天积累的脂肪储备约为其无脂肪体重的10%，以度过漫长、寒冷的冬夜。从理论上讲，与体重相关的捕食风险可能是影响它们日常觅食规律的一个重要因素。我研究了越冬的褐头山雀（Parus montanus）的起飞能力与其脂肪负荷的关系。褐头山雀在黄昏时的平均体重比黎明时重7.7%，但体重对起飞能力没有可测量的影响。结果表明，褐头山雀在一天中积累的相对较少的脂肪负荷不会因起飞能力下降而增加被捕食的风险。版权所有1998年动物行为研究协会。
