Endangered Species: Whooping Crane

The Whooping Crane was placed on the endangered list in the year 1967.

The whooping crane is making a comeback after once being close to extinction, thanks to conservation efforts over the last several decades. There were only two small breeding populations of the whooping crane, which remained in 1937: a non-migratory group in southwestern Louisiana, and a migratory group that nested in Canada and flew in the winter to Texas.

Before all the settlers moved westward, whooping cranes made their homes from Illinois to southern Canada. They shared their nesting grounds with the grizzly bear, bison, and gray wolf. They migrated to places extending from the Carolinas to Mexico for the winter.

The settlers who came to the west took much of the crane's prairie nesting grounds; the land was made into pasture and agricultural lands. So, the whooping cranes disappeared from the Great Plains, to find safer refuge north into Canada.

Today approximately 145 whooping cranes migrate across the state of Montana to Aransas. Spring migration occurs from the late part of April to the middle of June. Whooping cranes may live to be 20 years old.

Whooping crane's habitats are in shallow wetlands that have cattails, bulrushes and sedges (any of numerous grasslike plants). You can also spot them in upland areas, especially during migration.

Whooping cranes don't reach sexual maturity until their second or third year. They mate in late April and May. The rituals are very odd, when the pair performs loud vocalizations, wing flapping, head bowing and then they leap into the air and they mate for life.

Their nests are constructed in plants with stems that grow out of the water, vegetation, which grows in marshes, sloughs, prairie potholes; bulrush being the dominant plant. Used nesting habitats are poorly drained and put together in a sloppy manner with many potholes, most with a soft loamy bottom. Potholes are separated by narrow ridges, which support an over layer of black spruce, tamarack, and willow.

After mating, two eggs which are olive-buff and covered with dark purplish brown blotches, are laid in a nest. It takes about 29 days for incubation. Both parents incubate the eggs and feed the young chicks. Sad to say, only the large chick survives due to its aggressive behavior.

Young cranes can fly in about 90 days. By the middle of November cranes have arrived at the wintering grounds, where they stay for about a half of a year. Cranes feed exclusively on blue crabs until January. They forage them from flooded tidal flats and sloughs (a stagnant swamp, marsh, bog or pond). By January the flats and sloughs have mostly drained, and cranes move into shallow bays and channels to eat on clams and an occasional blue crab. Whooping cranes swallow clams and small blue crabs whole. They drag larger crabs ashore and peck them into small pieces.

Since whooping cranes only lay two eggs but just raise one chick, Canadian and American biologists tried an experiment, by removing the extra eggs from the nests in the wild and then brought them to Maryland, where they artificially incubated them and later used the chicks to establish a captive flock. From 1967 through the present, many "extra" eggs have been transferred from the wild to the Patuxent center and other whooping crane captive breeding facilities.

In another attempt to replenish chicks into the population, biologists would take eggs from the nests that were laid by whooping cranes (the whooping cranes would then lay a second nest of eggs) the eggs taken would then be given to Sandhill cranes to hatch and raise them as their own. Then they would be introduced into the wild. To this date this has been quite successful!

What does a whooping crane look like? The whooping crane is the tallest bird in North America. It is white with black wingtips, and has red markings on the head. Until their second summer the young birds have a brown appearance. Whooping cranes are five feet tall and have a wingspan of seven feet. They fly with a slow downward flap and a rapid upstroke. The trumpet like call carries for miles, which is where they get their name. The bill is dark gray, becoming lighter as the breeding season is near. Legs and feet are usually black. The whooping crane's closest relatives in North America are five races of the sandhill crane.

Reasons for the whooping cranes decline are loss of habitat, shooting and collision into power lines. Those collisions have became the leading cause of the cranes deaths.

In March 2000, the first whooping crane born in the wild in the United States in 60 years was born in Kissimmee Florida. However, in May, the chick was killed by a predator, possibly a bobcat!

Today, there are nearly 300 whooping cranes in the wild and in captivity. They have come a long way and so have we!

References:

1) Whooping Crane (Grus americana)
(www.species.fws.gov/species_accounts/bio_whoo.html )

2) The Majestic & Endangered Whooping Crane (Grusamericana) An Alberta Canada Perspective
(www.raysweb.net/specialplaces/pages/crane.html)