"Things are going wrong with our environment," writes John Terborgh, "even the parts of it that are nominally protected. If we wait until all the answers are in, we may find ourselves in a much worse predicament than if we had taken notice of the problem earlier. By waiting, one risks being too late; on the other hand, there can be no such thing as being too early." Terborgh's warnings are essential reading for all who care about migratory birds...