Migrating birds straying from paths
Scarcities of food, habitat are suspected
MAD ISLAND, TEXAS | Strange things are aloft in the bird world.
Endangered whooping cranes flew 2,500 miles from Canada to Texas, where they usually spend the whole winter. Instead, they pecked around for a short time and flew back. In Nebraska, other cranes never left.
Some ducks just kept flying south all the way to Belize in Central America. And a snowy owl was spotted near Dallas, only the sixth time that’s ever happened.
Throughout the winter, scientists have noticed these and other examples of bizarre bird migrations a result, they believe, of flocks becoming desperate for food and habitat becoming increasingly scarce because of the stubborn drought in Texas. The unusually mild winter in the Northeast and Midwest has even persuaded some birds they could stay put, fly shorter distances or turn back north earlier than normal.
“We have birds scattered all over the place looking for habitat right now,” said Richard Kostecke, a bird expert and associate director of conservation, research and planning at the Nature Conservancy in Texas.
The concerns go beyond a few lost flocks. Migratory birds often use the winter months to rest, eat and gain energy for the long journey back to their nesting grounds, so biologists can only guess at the effects of this season’s peculiar movements.
What will happen if the birds’ diets are altered or if they expend too much energy? What if they fail to migrate at all? Will they still be able to breed after a stressful winter?
“You may see a cascade of impacts,” Mr. Kostecke said. “We don’t know exactly where things will end up.”
In a typical winter, the Texas Gulf Coast is packed with tens of thousands of birds songbirds, waterfowl, catbirds, gnatcatchers, warblers and other migrants. But this year, an annual count, done just before Christmas, found the population had dropped steeply.
The number of water-dwelling birds was down significantly. Geese, for example, were 61 percent below their 19-year average. Dabbling ducks dropped 43 percent, diving ducks 60 percent and spoonbills 74 percent.
Part of the problem is lack of food. The drought the worst one-year dry spell in Texas history parched thousands of acres of wetlands along the coast, a habitat that is normally rich with fish, seafood, berries and insects. Lucky for the birds, they can fly. “God gave birds wings for a reason: to pick up and find what they need,” said Dave Morrison, the small game director at the Texas Parks and Wildlife Department.
Geese fly over Mad Island, Texas, in mid-february. In a typical winter, the Texas Gulf Coast is packed with tens of thousands of migrating birds. But this year, an annual count just before Christmas found the population had dropped steeply.