Devices called geolocators are giving us new insights into how, when, and where birds migrate. They record daily changes in light levels at different latitudes and longitudes by recording the time of each sunrise and sunset. And by attaching them to migrating birds - like this Red Knot -…

On the grassy edge of one of the ponds at Hanalei Wildlife Refuge, we find a Nene -- or Hawaiian Goose -- a small goose found nowhere else but Hawaii. The Nene is the only state bird that is also an endangered species. Once common in the Hawaiian Islands before the first humans landed here…