The children belong to a club for young ornithologists .
孩子们是年轻的鸟类学爱好者俱乐部的成员。
Early ornithologists , puzzled by the disappearance each winter of the local swallow population , suspected that the birds buried themselves in mud and hibernated .
早期的鸟类学家,无法解释每到冬季时当地的燕子消失尽殆的现象,便怀疑它们把自己埋在烂泥中长梦过冬。
And because weissensee is such a deep forest , ornithologists doing serious birds of prey research show up to climb its trees and count the number of goshawk fledglings in cemetery nests .