The whooping crane – the tallest bird in North America (5 feet tall with a wingspan of 7.5 feet) and one of the rarest – is the leading symbol of wildlife-conservation efforts in the United States. In 1941, the species’ total population had dwindled to 15 cranes, discovered wintering on the Texas coast. The American Birding Association reported a species population of 599 last September, including 278 cranes in the group that migrates 2,500 miles between nesting grounds in Canada’s Wood Buffalo National Park and wintering habitat around Texas’ San Antonio Bay, north of Corpus Christi.The drought in Texas has the world’s only wild flock of whooping cranes facing a “rough” and “difficult” winter. But U.S. wildlife officials are optimistic that the giant bird — one of North America’s most endangered species — will survive the season in good health with help from an emergency acorn roast.Unusually dry conditions along the Gulf Coast in Texas have posed a serious challenge for the cranes, prompting state conservation officers and an army of volunteers in the region to implement drought-mitigation plans aimed at ensuring the vulnerable birds have adequate access to fresh water and food supplies.The worrisome die-off of about 25 whoopers in Texas during the winter of 2008-2009 has been blamed on restricted water flows from the Guadalupe River that disrupted the cranes’ food supply and other aspects of its feeding regime in the Aransas refuge.An array of windmills around the Aransas refuge, some requiring extensive repairs or maintenance, have been kept running full tilt to pump water to the otherwise parched surface, attracting whoopers and other animals that can’t drink from traditional coastal marshlands that have become too salty from lack of rain.And to supplement the cranes’ principal diet of blue crabs and wolf berries — which were harder than usual to obtain in the first weeks after the birds’ arrival from Canada — wildlife officials carried out controlled burns throughout the Aransas refuge to give the endangered cranes a crucial nutritional supplement: roasted acorns.The managed fires in the area, located north of Corpus Christi, don’t damage the oak trees but burn the underbrush and roast the fallen acorns.The additional food should help the cranes build up energy reserves to stay healthy during the unusually dry winter and make their return trip to Canada this spring.There’s a non-migratory flock in Florida and a Wisconsin-based migratory flock that has been trained to follow an ultra-light aircraft to Florida each winter as part of another unique, Canadian-led recovery project.The birds are reared by conservationists in bird suits that conceal their human features. They become conditioned to follow the suited handlers and a plane engine.On the migratory route, the cranes follow the small plane flown by a pilot in a bird costume. The flock flies from 25 to 50 miles a day. Once the route is flown the birds can make the return flight on their own.As noted previously, one flight corridor for whooping cranes runs from western Canada to the Aransas National Wildlife Refuge in Texas. The new flight corridor is part of an effort that started in 2001 to restart an eastern U.S. flyway from Wisconsin to Florida.The goal is to create a new wild flock and this is their historical range. About 90 cranes have been established on the eastern route since 2001. They have started to reproduce in the wild in a slow expansion, with sexual maturity reached at six or seven years.Earlier this year, U.S. wildlife officials also announced plans to create a new flock in Louisiana, part of a proposed diversification of winter feeding sites that is considered crucial to eventually removing the species from the North American endangered list.In 2010 the Texas/Canada whoopers did exceptionally well. The 2010 baby boom has been attributed to ideal water conditions in Wood Buffalo where the cranes are highly protected and carefully monitored during their annual summer stay.This year, a number of birds were also captured and fitted with satellite tags to allow better tracking of the flock in the coming years. Individual birds can live longer than two decades.Whooping cranes move in small family groups. It seems as though there is an unusual dispersion of the whoopers this year in Texas due to the continuing drought, so keep an eye out for these magnificent birds, you might get lucky and have one in your own back yard!