Liz Simmons, age 13, of Sardis, Alabama, for her question:

Do whooping cranes outnumber trumpeter swans?

Both these beautiful birds hang on the brink of extinction, though we are doing our level best to save them. The proud trumpeter swans have a somewhat better chance of survival because there are more than 2 thousand of them left. The whooping cranes were never very plentiful. But their numbers now are so small that a single accident could wipe them all out.

For many years, conservationists have been striving very hard to save the whooping crane from extinction. When the settlers arrived, the entire population of these birds in North America is estimated to be around 1,500. And, wouldn't you know, the handsome birds were slaughtered without mercy. Then, in 1938, a natural flood disaster wiped out an entire flock. Only 22 survivors could be counted.

But the whooping cranes survived, with a great deal of help from their human friends. Slowly, year by year, their numbers increased. The surviving flock increased to 30, then to 35. Counting a flock of wild birds is not easy, especially when the flock migrates from a winter refuge by the Gulf Coast to an almost secret nesting area in Canada. Recent estimates set the number of surviving whooping cranes at somewhat less, but not more, than 50.

Other members of the handsome crane family are declining around the world. Many perish when the marshlands where they live are drained for farmlands and housing. In most of their native regions, they are driven out to make room for more people. The Manchurian crane is barely hanging on in parts of Siberia and Japan. However, it's nice to know that our sandhill crane is flourishing in North America.

It seems that the big beauteous swans are, and always were, too gorgeous for their own good. Most likely none of them could survive without the protection of strict conservation laws. The stately white mute swan is a native bird of England. But all of these wild swans had been wiped out by the 1200s. Later, tame    or partly tame    mute swans were declared the property of the king or queen, meaning no one could harm them. They now survive in large numbers.

At one time, the great trumpeter swans were plentiful all over North America. But mindless hunting has reduced them to the status of an endangered species. They now are limited to a region of southwestern Canada and northwestern United States. And the surviving population of trumpeter swans is estimated to be no more than 1,500.

With strict conservation laws, we can hope to save both our trumpeter swans and our whooping cranes. Meantime other big birds are declining as they are driven from their native breeding grounds. The problem is not easy, for when the birds are reduced to a few individuals, the species usually becomes extinct. With the whooping crane we were lucky because these birds were used to living in rather small groups.