Thursday, April 23, 2009

Reader questions about birds

Reader questions about birds

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A reader in Elburn, Illinois, west of Chicago, wrote, I have three sandhill cranes [pictured] nesting in my backyard right now. I saw on a Website that they are endangered in Illinois and was curious if that is really true.

Sandhill cranes, which are among the most magnificent birds of North America, and cousins to the endangered whooping crane, were never threatened nationally, but they were absent as a breeding bird in Illinois from 1872 to 1979. Over the past couple of decades, however, the number of sandhill cranes breeding in the state has increased steadily, and in 2000 the Illinois Department of Natural Resources counted 140 individuals in northeast Illinois. Since then, the population has increased by an annual rate of 33 percent. Hence the Illinois Endangered Species Protection Board is currently in the process of removing sandhill cranes from the list of state threatened birds.

According to Mike Ward, an ornithologist with the Illinois Natural History Survey at the UI and a member of the technical committee that advises the state Endangered Species Protection Board, there is an unfortunate flip side to this story, though. That’s because the recent success of sandhill cranes in the state is attributable to changes in the structure of wetlands that are detrimental the majority of other birds that depend on them for breeding. So while sandhill cranes have increased, seven other species of wetland birds have experienced statistically significant population declines. Most notable among these are common moorhens, black terns, least bitterns, and yellow-headed Blackbirds.

A neighbor called recently to ask, what should I do with the nest where a mallard has laid eggs in a bush by our house?

The best thing people can do for nesting birds is to leave them alone and keep pets away from them. It’s okay to replace eggs or baby birds that have fallen from a nest—bird parents really are not put off by scents from human handling—but the general principle to follow is “let wildlife stay wild.”

This principle applies to baby rabbits, baby deer, and other critters as well.

A reader in Champaign County e-mailed to ask, when can we expect to see eastern bluebirds and American goldfinches return? Are they already in transit from their winter quarters?

Experienced birders love to field the question about goldfinches because the answer comes as such a surprise. The fact is goldfinches do not leave Illinois for the winter. [Photo: a male American goldfinch in transition from winter to breeding plumage.]When they molt in the fall both males and females of the species put on a coat of olive feathers so drab that many people don’t recognize them. It’s when they molt again in spring that the appearance of male goldfinches becomes remarkable as their bright yellow breeding plumage comes in.

Bluebirds that breed in Illinois don’t move far for the winter, either, migrating only as they are forced to by weather and limits on the availability of food. Some bluebirds can be seen in east central Illinois through most winters. Bluebirds that have wintered farther south move back to or through the Midwest between the end of February and early May.

While we’re on the topic of migration, I would add that the next three weeks or so offer some of the best bird-watching opportunities of the year, as brightly colored warblers and other long-distance migrants return to their breeding territories.

If you’re wondering where to start seeing them, the Sunday morning bird walks conducted by the Champaign County Audubon Society at Busey Woods in Urbana offer a great place to start. These walks depart from the Anita Purves Nature Center at 7:30 a.m. and last as long as participants care to stay out.