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Whooping Crane Background Facts
- The whooping
crane, considered to be the icon of endangered species,
once inhabited much
of North America. It is the rarest of the world's 15 crane
species. The species' historic decline, near extinction,
and gradual recovery
is among the best known and documented conservation stories.
- Concern over the near extinction of the whooping crane has prompted a broad range
of conservation actions. these include national and international legal protections;
comprehensive scientific research and monitoring programs; protection of key habitats;
development of whooping crane recovery teams and comprehensive recovery plans; and
extensive public education campaigns.
- Without help and intervention, whooping cranes will not survive.The species declined
rapidly in the late 1800s and early 1900s as a result of hunting, collecting, and
the conversion of its habitats to agriculture. By 1940, only the one self-sustaining
flock remained. All whooping cranes alive today are descendents of these few cranes:
fewer than 20 individuals, about 3 or 4 nesting pairs. This meant only 4 or 5 genetic
lines to carry on the species.
- Since the mid-1960s, captive breeding has provided security against extinction
of the species while allowing opportunities to initiate new populations.
- The key to their survival of the species is to add geographically separated migrating
populations. The separation keeps the birds safe from transmitting diseases that
could wipe out the flock, or from being wiped out by human-caused, weather, or environmental
catastrophes.
- The world's only self-sustaining wild population is protected on public lands
in the nesting area at Wood Buffalo National Park in Canada and on the principal
wintering area at Aransas National Wildlife Refuge in Texas. This population is closely
monitored throughout the nesting season, on the wintering grounds, and during migration.
It is sometimes referred to as the Aransas/Wood Buffalo flock.
- Besides around 174 birds in the Aransas/Wood Buffalo flock (2001 figures), the
world's wild whooping cranes also include the tiny core population of the new Eastern
migratory flock started in 2001, about 75 whoopers in a nonmigratory flock in Florida,
and two whoopers in the Rocky Mountains. About 140 captive whooping cranes (2001
figures) live in breeding centers in North America (Patuxent WRC in Maryland, ICF
in Wisconsin, Calgary Zoo in Canada, San Antonio Zoological Gardens in Texas, Lowery
Park Zoo in Tampa, Fl, and the Audubon Institute, New Orleans).
- Recovery to nearly
400 whooping cranes could not have happened without the efforts of
the governments and people of both the United States and Canada. Thanks
to captive
breeding, an experimental non-migratory population inhabits
palmetto grasslands, savannahs, and shallow marshes in the Floridaís
Kissimmee Prairie region.
- The Whooping Crane occurs exclusively in North America. The historic mid-continental
breeding range stretched from Alberta across the northeastern portions of the mid-continental
prairies to near the southern end of Lake Michigan. The historic wintering grounds
included the highlands of northern Mexico, the Texas Gulf coast, and portions of
the Atlantic coast. Non-migratory populations occurred in Louisiana and possibly
other areas in the southeastern United States.
- Whooping cranes learn their migration oute from their parents. In this way, a
route established a million years ago is passed from one generation to the next.
If birds are extirpated from an area, the route is lost too.
- Using the techniques developed by a non-governmental organization called Operation
Migation, whooping cranes are being taught a migration route between Wisconsin and
Florida. The ultralight-led migration is part of the effort to establish a new flock
of wild, migratory whooping cranes in eastern North America. The whooping crane reintroduction
was begun in the summer of 2001. Ultralight-escorted migrations will be part of the
plans for approximately five more years as a core population is established and young
cranes can begin learning the migration route from following adults in the Wisconsin/Florida
flock.
- Whooping cranes continue to face multiple threats, including habitat loss and
pollution from contaminant spills in their traditional wintering grounds, collision
with utility lines, human disturbance, disease, predation, loss of genetic diversity
within the population, and vulnerability to natural and human-caused catastrophes
and the impacts of human population growth. The primary threats to captive birds
are disease and parasites. Bobcat predation has been a serious problem with the Florida
experimental non-migratory population.
- Whooping cranes need good habitat to survive. They need to roost in water at
night in order to feel safe from predators. Traditionally, this water is 13-20 cm.
deep. When the chicks are very small, they might roost on islands surrounded by open
water where the adults roost.
- Wetlands
provide good crane habitat. Cranes nest in open water areas
by building a platform of reeds and grasses that are raised above
the water's
surface. Good nesting areas generally require water less
than 3 feet deep, but preferably around 18 inches
deep. Whoopers are very wetland-dependent birds, so the wetland
must not dry out entirely during the year.
- Whooping
cranes mainly feed on blue crabs, clams, shrimp, aquatic
invertebrates, small vertebrates, frogs, and plant roots, seeds and
berries.
In adjacent uplands, whoopers are known to forage for acorns,
snails, insects, rodents and other food
items. Waste grain is an important food along the migratory
route. Cranes have been recorded to eat snakes, small birds
and basically anything they can get their beaks
on.
- Cranes
prefer poorly drained areas with numerous shallow-water wetlands
with soft bottoms. Often these wetlands are separated by
narrow ridges where spruce, willow, birch and tamarack trees
grow. Cattail, sedges and rushes grow in the waterways.
Whoopers visit
agricultural lands usually only during
migration, when waste grain is a food source, and then it's
usually the non-family groups. (The families continue to
use wetlands more.)
- Whooping
cranes migrate singly, in pairs, in family groups or in very
small flocks. Whooping cranes are sometimes accompanied by
sandhill cranes. Whoopers are not as social or as robust
as their non-endangered cousins, the sandhill
cranes. Whoopers are diurnal migrants,
stopping regularly to rest and feed, and use traditional migration
staging areas. On the wintering grounds, pairs and family
groups occupy and defend territories.
- Immatures are a reddish cinnamon color that results in a beautiful mottled appearance
as the white feather bases extend. The juvenile plumage is gradually replaced through
the winter months and becomes predominantly white by the following spring as the
dark red crown and face become apparent. Yearlings achieve the typical adult appearance
by late in their second summer or fall.
Journey
North is pleased to feature this educational adventure made possible
by the
Whooping Crane Eastern Partnership (WCEP).
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