Return of the species

 

 
 

1. Wolves. Endangered?
2. Wolves on the rebound
3. History of extermination
4. Midwestern wolves
5. Causes of extinction
6. Trumpeter swan sings
7. Wisdom of reintroductions
8. Helping the plants
9. Moving the plants
10. Genetics movement
11.House flies!

 

 

RIGHT: One big scavenger, the condor looks down from a perch.
Courtesy: Glenn Smart,
U.S. Fish & Wildlife Service

 

   Declines of other species
A white crane stands on one leg, big bill pointing down and away from camera.
A captive whooping crane in a breeding pen at the International Crane Foundation.
© David Tenenbaum

Many species have verged closer to extinction than the gray wolf. Although the causes vary, humans played a role each time:

Whooping crane
Causes: habitat loss, shooting for feathers for the hat trade, collisions and electrocution at power lines, avian tuberculosis, avian cholera and lead poisoning.

Bald eagle
Cause: DDT poisoning caused reproductive abnormalities and thinning of egg shells. (DDT breaks down into a chemical similar to the hormone estrogen, disrupting the endocrine system and causing the weak shells.) The Fish & Wildlife Service has proposed removing the bird from the list of endangered species.

California condor
Cause: urbanization reduced open condor habitat; birds were poisoned by eating lead shotgun pellets and poisons aimed at other animals, and electrocution by power lines.
Black body, white under the wings, and a naked red head. All the better to crunch carrion with! illustration of a condor

 

 

 

 


Is your band ready for a trumpeter (swan, that is?)

 
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  The Why Files   There are 1 2 3 4 5 6 7 8 9 10 11 pages in this feature.
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