Federally Listed Endangered, Threatened, and Candidate Species 1995
Whooping Crane (Grus americanus)
Official Status: Endangered
Endangered species are species that are in danger of extinction throughout all or a significant portion of their range. It is unlawful to kill, harm, or harass endangered species.
Listed:
35 Federal Register 8495; June 2, 1970
Historical Status:
The historical breeding range of
the whooping crane extended from Illinois, northwest through North Dakota, and up to the Northwest Territories. The last nesting record for North Dakota was in McHenry County in 1915. The birds historically wintered along the Gulf of Mexico. By the 1940's there were an estimated 21 whooping cranes left in the world. Most were from a flock that wintered at the Aransas National Wildlife Refuge on the coast of Texas. It was later discovered that the birds were breeding in Wood Buffalo National Park in the Northwest Territories.
Present Status:
There are presently about 145
whooping cranes in the wild. About 132 birds are in the Aransas-Wood Buffalo flock and 13 birds are in a flock that migrates between Grays Lake National Wildlife Refuge in Idaho and Bosque del Apache National Wildlife Refuge in New Mexico. The Aransas-Wood Buffalo population migrates through North Dakota. During the 1991 fall migration there were 8 sightings in North Dakota from late September to mid October. The spring migration occurs from late April to mid June. Birds can show up in all parts of North Dakota although most sightings occur in the western 2/3 of the state.
Habitat:
Whooping cranes inhabit shallow wetlands that are characterized by cattails, bulrushes and sedges. They can also be found in upland areas, especially during migration.
Life History:
Whooping cranes do not appear to reach
sexual maturity until their 2nd or 3rd year. Courtship occurs at Wood Buffalo National Park in late April and May. Courtship rituals are eccentric with the pair performing loud vocalizations, wing flapping, head bowing and leaps into the air. Whooping cranes mate for life. Two eggs are laid in a nest made of bulrush and other vegetation. Incubation is about 29 days. Both parents incubate the eggs and feed the young. Usually only the larger chick survives due to its more aggressive behavior. Young cranes are capable of flight in about 90 days. Whooping cranes may live 20 years. Whooping cranes feed on crabs, crayfish, frogs, and other small aquatic life as well as plants.
Aid to identification:
The whooping crane is the
tallest bird in North America. It is a white bird with black wingtips and red markings on the head. Young birds have a brown-mottled appearance until their second summer. Whooping cranes are 5 feet tall and have wingspans of 7 feet. Whooping cranes fly with a slow downward flap and a rapid upstroke. Whooping cranes may migrate with the smaller, gray, sandhill crane. The trumpet like call carries for miles.
Reasons for decline:
Loss of habitat and shooting
are the main reasons for the whooping crane's decline.
Recommendations:
Many of the wild whooping
cranes are marked with colored leg bands. Make observations of these birds and report them to a wildlife agency.
Comments:
The status of whooping cranes in the wild
is precarious because the birds concentrate during the winter Oil spills in the Gulf of Mexico are a potential threat. Eggs from wild birds (1 per nest) have been removed and hatched in captivity. The captive birds are now reproducing.
References:
Whooping Crane Recovery Plan by U.S. Fish and Wildlife Service.