Saving North America’s Tallest Bird
Whooping crane recovery is one of conservation's great successes, but suddenly there are new and frightening threats.
On the cold, misty morning of February 12, 2013, Iliana Pena, conservation director for Audubon Texas, and I are trying to feel good about the future of whooping cranes. In Captain Tommy Moore's metal birding boat, Skimmer, we are cruising the Intracoastal Waterway inches from the western shore of the Aransas National Wildlife Refuge on the Texas Gulf Coast. With us is Wade Harrell, whooping crane recovery coordinator for the U.S. Fish and Wildlife Service.
In 1937 President Franklin D. Roosevelt designated the refuge, thereby protecting the 47,200-acre Blackjack Peninsula between Aransas and San Antonio bays. Since then it's grown to 115,000 acres and been named a Globally Important Bird Area. Today the refuge helps sustain somewhere between 178 and 362 whooping cranes, up from 15 in 1941. The Fish and Wildlife Service thinks the number is probably around 257 but can't say for sure because it has come up with a controversial new system of estimating rather than counting. These birds migrate from breeding grounds in northern Canada to wintering habitat here in south Texas.ultralight aircraft, migrates between Necedah National Wildlife Refuge in central Wisconsin and Chassahowitzha and St. Marks National Wildlife Refuges on Florida's west coast. They're doing well in the wild but reproduction is low. A non-migratory flock established at Kissimmee Prairie Preserve State Park in south-central Florida seems to have failed, but another of about two dozen in southwest Louisiana shows great promise.
During the past 70 or so years the naturally migrating population has increased at an average of 4.5 percent annually. Still, Pena and I have a bad feeling about the onslaught of new threats in Texas--climate change that is flooding salt marshes and bringing habitat-wrecking black mangroves up from the south, and coastal development, drought, and water withdrawals from the Guadalupe and San Antonio rivers that have raised salinity in bays and estuaries, thereby killing the blue crabs and other invertebrates that sustain the cranes. A recent federal court decision may have resolved the water-withdrawal issue, but persistent drought, possibly related to climate change, remains a concern.
Even on dark days, birders have to work to sustain dark moods in the Aransas National Wildlife Refuge. Opening the show for us and eliciting smiles from all hands are reddish egrets dashing around the marsh, hopping and changing direction like Keystone Kops. A seaside sparrow carols from his spartina perch. Great blue herons in astonishing profusion hunch, puff, and preen. Ospreys hover and perch on buoys. Great and snowy egrets stalk salt ponds and scull overhead. White pelicans in tight clusters roost on sandbars. Brown pelicans fold their wings and dive. A northern harrier wobbles low over the marsh. Patrolling the wet flats are dunlins, marbled godwits, willets, long-billed curlews, dowitchers, oystercatchers, avocets, greater yellowlegs. A white-tailed hawk amiably shares a roost with seven great blue herons. Bottlenosed dolphins roll in our wake and bow wave. Are we really getting paid for this? Pena and I ask ourselves.