The whooping crane (Grus americana) has long been considered the symbol for wildlife conservation in the United States. This large, white, wading bird of the family Gruidae is our tallest North American bird, standing nearly 5 ft (1.5 m) tall and having a wingspan of 7.6 ft (2.3 m). Whooping cranes have been threatened with extinction since the twentieth century. Overhunting in the latter part of the nineteenth and early twentieth centuries, as well as habitat loss—primarily due to the conversion of prairie wetlands into agricultural land—have been major contributors to this decline. In modern times, the number one cause of death in fledged birds has been collision with high power lines.

In 1937 the federal government established the Arkansas National Wildlife Refuge on the south Texas coast, which is the wintering grounds for the whooping crane, in order to protect this species' dwindling population. At the time the...