Tuesday, December 27, 2011

One of World’s Rarest Birds Winters In Western North Carolina

Biologists recently confirmed the presence of a pair of whooping cranes outside Hayesville, North Carolina, marking the first time the birds have been documented wintering in Western North Carolina.

Whooping crane
Credit:  U.S. Fish & Wildlife Service 

Whooping cranes are one of the rarest species in the world, with a current estimated global population between 525-550 individuals, which is divided into four main groups. All wild whooping cranes are part of a western population that migrates between Canada and coastal Texas and now numbers approximately 300. In 1999 state and federal agencies, non-profits, and private individuals formed the Whooping Crane Eastern Partnership (WCEP) to restore a migratory flock to eastern North America. This carefully-managed and heavily-monitored eastern flock began with a small group of captively-reared birds which has grown to more than 100 individuals, including the two found in Clay County. The third and fourth populations are reintroduced populations of nonmigratory whooping cranes in Florida and Louisiana.

The Western North Carolina sighting of whooping cranes was reported through the BringBacktheCranes.org website on December 9, 2011 by Paul Hudson, of Hayesville, N.C. After the initial report, Jennifer Davis, of the International Crane Foundation, joined Hudson and confirmed his sighting upon finding the birds foraging in a soybean field.

“With Jennifer’s great tracking abilities and my local knowledge, we found the birds again and got to view them from a safe distance. They lifted their giant wings and displayed while calling, which echoed across the valley,” said Hudson. “What wonderful creatures they are, and I got two chances to see them in the wild. How cool is that?”

Since Hudson’s first sighting, at least two other people have reported the birds.

“We’re pleasantly surprised that we’re beginning to get a steady stream of reports, since the birds don’t usually pass through Western North Carolina and we haven’t put out a call for people to report sightings,” said Billy Brooks, a U.S. Fish & Wildlife Service biologist who has spent years working with whooping cranes. “It’s wonderful to see people recognizing that these birds are something special in their community.”

The cranes are a male/female pair, and biologists anticipate they’ll mate when they return north in the spring. Like all members of the eastern population, the birds have identifying leg bands. The male goes by the number 28-08, meaning he was the 28th chick hatched to the eastern population in 2008. The female is 5-10, the fifth chick hatched in 2010.

When young eastern whooping cranes make their first southward migration, they follow closely related sandhill cranes, older whooping cranes, or an ultralight aircraft which leads the birds south from Wisconsin, across Tennessee and Alabama into Florida. After that first guided migration, the birds are on their own to select a route and a wintering area. The male of this pair spent last winter at Hiwassee Wildlife Refuge in southeast Tennessee, along with a handful of other whooping cranes which winter there with thousands of sandhill cranes. While Clay County is outside the main migration corridor, it isn’t far enough to worry biologists.

It remains to be seen whether the pair will make Western North Carolina their annual wintering ground. Aside from ecological factors, it may depend, in part, on the behavior of Western North Carolinians. Brooks advises anyone encountering a whooping crane in the wild to give them the respect and distance they need. WCEP recommends not approaching the birds on foot within 600 feet; remaining in your vehicle; not approaching in a vehicle within 600 feet or, if on a public road, within 300 feet; remaining concealed and not speaking loudly enough that the birds can hear you; and not trespassing on private property in an attempt to view whooping cranes. These birds are protected by the Migratory Bird Treaty Act and the Endangered Species Act.

“It’ll be fascinating to see if these birds remain in Western North Carolina,” said Brooks. “There are a lot of factors that play into that – not only human disturbance, but also whether the habitat has what they need to over-winter.”

Whooping cranes were listed as an endangered species in 1967, the result of hunting and specimen collection, human disturbance, and loss of habitat. Whooping crane numbers dipped to an all time low of 16 individuals in 1941. They once occurred from the Arctic coast to the high plateau of central Mexico, and from Utah east to New Jersey and Florida. Standing almost 5 feet tall, it’s the tallest bird in North America. Adult birds are characterized by snowy white plumage, a crimson crown, long thin black legs, and white wings tipped with black that measure almost 8 feet in length. The plumage of juvenile birds is a mixture of cinnamon and white. Deriving their name from the distinctive whooping call, the call of the whooping crane can carry for miles.

Recognizing that the few remaining wild birds had become concentrated in small areas, scientists became concerned that a single catastrophic event on either the wintering or nesting grounds could wipe out the population. This led to efforts to establish additional, separate populations.
The Whooping Crane Recovery Team, a group of biologists that provide policy and recommendations for the species, searched for possible locations to establish a second migratory flock. In 1999, the team recommended that a flock of whooping cranes hatched in captivity be taught a migration route between central Wisconsin and the west coast of Florida. The recovery team then sanctioned the ultralight-led migration techniques of Operation Migration, Inc. as the main reintroduction method.

In 2001, Operation Migration's pilots first led captive-reared whooping crane chicks south from Necedah National Wildlife Refuge in Wisconsin to Chassahowitzka National Wildlife Refuge in Florida. This effort to guide young cranes to wintering grounds has become an annual event and is considered key to establishing the eastern population. To prepare for the journey and release into the wild, the young cranes are introduced to ultralight aircraft and raised in isolation from humans. Project biologists and pilots adhere to a strict no-talking rule, broadcast recorded crane calls, and wear costumes designed to mask the human form whenever they’re around the cranes.

In addition to the ultralight-led method, biologists from the International Crane Foundation rear whooping crane chicks that are released in the company of older cranes, from whom the young birds learn the migration route, part of WCEP’s “Direct Autumn Release” reintroduction method.

Founding members of WCEP include the International Crane Foundation, Operation Migration, Inc., Wisconsin Department of Natural Resources, the U.S. Fish & Wildlife Service, U.S. Geological Survey's Patuxent Wildlife Research Center and National Wildlife Health Center, the National Fish and Wildlife Foundation, the Natural Resources Foundation of Wisconsin, and the International Whooping Crane Recovery Team. Many other flyway states, provinces, private individuals and conservation groups have joined forces with and support WCEP by donating resources, funding, and personnel. To report a crane sighting or learn more about the project, visit the WCEP website at http://www.bringbackthecranes.org.

Contacts and sources:
Billy Brooks, U.S. Fish & Wildlife Service
Joan Garland, International Crane Foundation 

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