フィールド日記

先週の生物基礎のフィールドワーク中に、ススキ野原でクヌギの枝に刺さったニホントビナナフシを見つけました。モズのはやにえと考えられます。モズのはやにえとは、野鳥のモズが捕らえた獲物をすぐに食べず、木の枝などに刺しておいたものです。はやにえのはたらきは諸説ありますが、最近の研究によると、繁殖期前にはやにえを食べることで、オスの歌の質が高まり、より強くメスを引き付けることがわかったそうです。


We found a stick bug called "Nihon Tobinanafushi(ニホントビナナフシ)", which was impaled on a twig of a SawTooth oak tree during our fieldwork in Basic Biology class last week. It seemed a prey impaled by a Bull-headed Shrike bird, called "Mozunohayanie (モズのはやにえ)" in Japanese. Bull-headed Shrike birds have a custom that they catch a prey and impale it on a twig for their later consumption. There are some hypotheses why they do so. According to a recent study, they eat impaled preys before their breeding period so that they can sing better and attract females more.