Nestled in the middle and lower reaches of the Yarlung Zangbo River, Metog county in the southeastern part of the Xizang autonomous region boasts a unique vertical climate encompassing tropical, subtropical, temperate and alpine zones, and has long been considered one of the country's top biodiversity hot spots. It is renowned for its abundant wildlife and plants, with 110 species of mammals, 554 species of birds, 61 species of reptiles, 61 species of amphibians and over 4,500 species of vascular plants, including more than 500 wild orchid species."The checklist of its birds is longer than those of many provinces in East China," said Que Pinjia, an ornithologist from the Chengdu Research Base of Giant Panda Breeding and the Sichuan Key Laboratory of Conservation Biology for Endangered Wildlife.