Larry Lyons: Whooping cranes not as resilient as their sandhill cousins

Published 12:30 pm Thursday, April 15, 2010

lyonsFrom all the responses to last week’s column on sandhill cranes it appears I should follow up with our only other North American crane, the much rarer whooping crane.

Standing five feet tall and wings spanning over seven feet, they’re the largest bird in North America.  Snow white in color with a black face mask and dark red crown, they can be mistaken for no other. While the sandhill has recovered marvelously the endangered whooping cranes have not been so lucky.

The original summer range of the whooping crane was the upper Midwest extending up into central Canada where they nested in shallow swamps scattered amongst the spruce forests.

Most wintered along the Texas Gulf Coast. They’re not picky eaters, relishing all manner of small critters, crustaceans and a variety of plants. Unlike the sandhills, there never were a lot of whooping cranes. In the 1860s when they were still relatively undisturbed, their population is estimated to have been only about 1,400 birds. As humans moved in, unregulated hunting and draining of their critical wetland habitat began to take its toll. They are also simply intolerant to human presence. Their numbers continued a downward spiral and bottomed in 1941 when there were less than two dozen whooping cranes left in the wild. All of these were nesting in northern Alberta at what is now Woods Buffalo National Park. It’s likely that this park established to protect the woods buffalo also saved the whoopers.

Teetering on the brink of extinction at the onset of a world war is not a good place to be, but the whoopers somehow hung on though their numbers remained just a couple dozen.

Starting around 1970 we got serious about bringing whooping cranes back. The first approach was to put eggs from captive whooping cranes into wild sandhill crane nests. This continued through the 1980s but turned out to be a wasted effort. The whoopers, having no mirrors, insisted they were sandhills and would only pair up with sandhills, not those other weird whooping cranes. Also, for some reason only a low percentage migrated successfully.

Next we tried establishing a non-migratory population in Florida. However, mortality was high and there was little reproduction so a while back we quit adding birds. Today this group numbers around 50 birds.

In 2001 it was decided to try establishing a new eastern population. This is a hugely ambitious project. The Necadah Wildlife Refuge in Wisconsin was chosen for the nesting area and Florida would be the wintering grounds. Like geese, cranes learn the migration route from their elders so they would have to be taught where to migrate. This had already been successfully done with geese using ultra-light airplanes. Eggs of captive whooping cranes were exposed to crane calls and ultra-light engine noise. Once the chicks hatched they never saw or heard a human. The pilot to whom they imprinted on wore a whooping crane costume. Caretakers wore bag suits which disguised the human form and they carried whooping crane puppets.

Eventually the young birds were taken to pens in the marsh and taught to forage and roost in the proper places by the disguised, puppet carrying caretakers. At migration time the young whoopers dutifully followed the ultra-light to Florida. They must have amazing memories for the following spring, entirely on their own, they all successfully returned to Wisconsin. I can just imagine it. “Hey, Gus, weren’t we supposed to hang a left back there? Golly, Sarah, I can’t remember. How do you remember it Fred? I dunno, let’s take a vote.” They’re now releasing captive reared chicks with wild whoopers to migrate naturally and despite setbacks, like an entire flock of 18 being killed by a tornado, this spring’s tally is 85 birds.

Currently the Woods Buffalo population, which has never been artificially bolstered, is about 260. The Wisconsin group is at 85 and the Florida gang stabilized around 50. That’s a total of 395 wild whooping cranes. However, they are far from secure. Being confined to just one small area leaves each group highly vulnerable to a single catastrophic event such as severe drought, extreme weather or pollution.
Carpe diem.

Larry Lyons writes a weekly outdoor column for Leader Publications.
He can be reached at larrylyons@verizon.net