剧情简介：Birding is the fastest growing wildlife-related activity in the U.S., and even conservative estimates put the current number of U.S. birders at 50 million. According to the New York Times, some authorities predict that by 2050 there will be more than 100 million—and the National Geographic Field Guide to the Birds of North America will be the essential reference for field i...(展开全部)
作者：Jon L·Dunn
出版社：National Geographic
ISBN：9780792253143
