The
Whooping Crane
by Jon M
Class 703- Dolphin Senior Public School
Mississauga, Ontario
Introduction
The Whooping Crane (Grus Americana) is an endangered species. In the 1960's
its population went down to about 15. It was then in 1967 categorized
as an endangered species, and is now protected by law. Now it's population
is about 180. The Whooping Crane is a migratory bird. It spends it's winters
in Port Aransas Texas and migrates up to Wood Buffalo National Park in
the Northwest Territories during the summer to breed. It is about 114-127cm
tall with the wingspan of 2.3m. It is the tallest bird in North America.
It is pure white with jet black wing tips and legs, and red cheeks and
forehead. Before maturity it has a brown neck and head. The Whooping Crane
has a trumpet like call that could be heard for many kilometres.
Distribution/Range
Distribution is how they spread out on the land. Range is the places that
they live. The Whooping Crane migrates to Wood Buffalo National Park,
Northwest Territories in the summer to breed, and migrates back to Port
Aransas, Texas for the winter. Wood Buffalo National Park's habitat is
mostly tall-and-mixed-grass prairies. At Port Aransas, the habitat is
mostly grasslands, coastal marshes, and other wetlands. Wood Buffalo National
Park is made up of mostly tall grass and is set up more like a park, where
as Port Aransas has more of a marsh wetland surrounding. The climates
in both ranges have quite different winter temps, and very different summer
temps, but Port Aransas' winter temperature and Wood Buffalo's summer
temperature are almost the same. Wood Buffalo's average temperature changes
from -24.5(C with no sunlight in January to 15.8(C with 372hrs of sunlight
in July. The average temperature in Port Aransas changes from 18.3(C in
January to 33.3(C in July. When in Wood Buffalo, the whooping Crane has
the entire park (44,807km2) to breed in. When in Port Aransas they stay
on a long strip of land on the coastline. The distance between them is
about 5,880km
Food
The Whooping
Crane eats Blue Crabs, Clams, Frogs, Minnows, Rodents, Small Birds, and
Berries. If it was too cold, then insects may not come out and frogs would
not be able to eat them which means the frogs would die and the Whooping
Crane would have less frogs to eat. Also many rodents may hibernate, so
the whooping crane would not be able to hunt.
If the photoperiod was longer then Whooping Crane would have more time
to hunt. If there is a shorter photoperiod than the Whooping Crane would
have less time to hunt. If the sun was out longer then the plants would
have more sun light to grow off of, this will lead to more rodents and
insects feeding off of them and both are preys of the Whooping Crane.
see: The Sun/Ecoystem Flowchart of the Whooping Crane
The way that a whooping crane hunts it's prey is by swooping down onto
it and snatches it up or it stands in a creek and pecks at prey near them.
It also nibbles at the roots of plants. If it was too cold then the plants
that it eats may not grow too well, and rodents may not come out.
Reproduction
The mating season of the Whooping Crane is April to May in the spring.
The first pair of Whooping Cranes started migrating on March 21, and on
April 1 this year (1999), Six adult pairs and one family group (2 adults
with their chick) have headed north. An aerial census flight was done
on March 25 and found only 164 out of the flock total of 183. They
breed in Wood Buffalo National Park in the Northwest Territories. The
Whooping Crane needs the temperature to be about 14(C to breed. It takes
29-31 days to incubate and in late May and early June they hatch. The
chicks fledge (leave the nest and learn to fly) at 80-90 days old. They
need to be laid in vegetation which is primarily bulrush and sedges, usually
in shallow portions of ponds, small lakes and wet meadows. The chicks
need to eat bulrush, which provides them with the nutrients they need
to survive. When chicks hatch they eat mollusks, crustaceans, insects,
minnows, frogs, and snakes. The average wild Whooping Crane lives for
24 years. The percentage of surviving up to 17 years is 84-100%. Scientist
snatch the eggs from the nest and use Sandhill Cranes to be foster parents
to keep the reproduction level higher.
Physiology
Physiology is how the animal is built and what conditions can it live
in. The Whooping Crane needs warm weather to survive. Freezing temperatures
would kill the Whooping Crane, because the plants and animals that it
eats would die. Snow would bury rodents making them hard to find. If there
was a drought it would dry up the wetlands and that is the main habitat
that the Whooping Crane lives in. A serious heat wave could cause insects
larvae to die or hatch prematurely, so that they die before the Whooping
Crane reaches the habitat that it would usually finds it, and prevents
Whooping Cranes from catching their prey, which could then change the
Whooping Cranes eating habits.
Conclusion
It is predicted that the Whooping Crane migrates because it is too hot
in Texas in the summer, and is too cold in Wood Buffalo in the winter
for the Whooping Crane to survive. But in the winter Port Aransas is about
14 degrees C, and in the summer Wood Buffalo is about 14 degrees C. They
also need more room to breed, each pair of Whooping Cranes has approximately
448 square km to breed in, but they have to share that room with other
animals.Since Wood Buffalo is a National Park it would have a lot of vegetation
for the Whooping Crane to feed on. The habitat is a lot safer for the
Whooping Crane because there are so few people in Wood Buffalo National
Park. It has been predicted that the photoperiod affects the Whooping
Crane because one parent has to stay behind and protect the nest, so the
other may have to hunt for both of them, a longer photoperiod provides
a longer hunting time. They arrive in Wood Buffalo in late April to mate
and leave in the end of September. The Whooping Cranes have all mostly
started their migration on the April 1st report. It has been predicted
that they will reach Wood buffalo National Park in the first 2 weeks on
May. The distance between them is 5,880 km, if they fly about 140km a
day, and they fly about 13 hours a day, they only have to fly 11km/h in
order to make the migration.
Sources
Books:
Encyclopedia of the animal world, The Water Birds, Fact On File, 1989
Internet:
www.electrotex.com/aoc/WhoopCrane97/WhooperMaps.html
www.wwfcanada.org/pictures/02-26-50.jpg
www.wwfcanada.org/facts/whopncrn.html
www.cbc4kids.ca/general/the-lab/endangered/199811/default.html
www.esul.k12ne.us/~rschroed/crane.html
www.tpdde.state.tx.us/nature/endangered/whooper.html
www.npwrc.usgs.gov/resorce/distr/birds/cranes/grusamer/html
bellnet.tamu.edu/whooping.html
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