Usherwood James R, Sparkes Emily L, Weller Renate
The Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
The Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK.
J Exp Biol. 2014 Sep 1;217(Pt 17):3002-5. doi: 10.1242/jeb.107169. Epub 2014 Jun 19.
Barn owls are effective hunters of small rodents. One hunting technique is a leap from the ground followed by a brief flight and a plummeting 'strike' onto an acoustically targeted - and potentially entirely hidden - prey. We used forceplate measurements to derive kinetics of the leap and strike. Leaping performance was similar to reported values for guinea fowl. This is likely achieved despite the owl's considerably smaller size because of its relatively long legs and use of wing upstroke. Strikes appear deliberately forceful: impulses could have been spread over larger periods during greater deflections of the centre of mass, as observed in leaping and an alighting landing measurement. The strike, despite forces around 150 times that of a mouse body weight, is not thought to be crucial to the kill; rather, forceful strikes may function primarily to enable rapid penetration of leaf litter or snow cover, allowing grasping of hidden prey.
仓鸮是小型啮齿动物的高效猎手。一种捕猎技巧是从地面跳起，接着短暂飞行，然后垂直“扑击”到通过声音定位的猎物身上，而这个猎物可能完全藏在隐蔽处。我们使用测力板测量来推导跳跃和扑击的动力学。跳跃表现与报道的珠鸡的数值相似。尽管仓鸮体型小得多，但这可能是因为它腿相对较长且在跳跃时使用了翅膀上拍动作而得以实现。扑击看起来是故意用力的：在质心更大的偏移过程中，冲量本可以在更长时间内分散，就像在跳跃和一次着陆测量中观察到的那样。尽管扑击时的力量约为老鼠体重的150倍，但人们认为这对捕杀并非至关重要；相反，有力扑击的主要作用可能是使仓鸮能够迅速穿透落叶层或积雪，从而抓住隐藏的猎物。
