Three eagles at the Iroquois National Wildlife Refuge
photo by Bob Johnson
This column is written in self-defense. Two or three times a week I receive a message asking me about the big bird the writer has seen: "It has a white head and tail. Could it possibly be an eagle?"
Don't get me wrong. I am always happy to hear from readers, but I'll save time with this column. Here's the definitive answer:
"Indeed, it is not just possible that you have seen an eagle, it is quite probable that you have done so. If the big bird you saw had the white head and tail you described, it is a bald eagle, our nation's emblematic bird, often called the American eagle for that reason. If it was all dark, it still could have been an eagle. The tail and head of bald eagles don't turn white until their fourth year. Rarely, during migration golden eagles also pass through the area. Soaring high overhead, you can occasionally identify these eagles by the white wing 'windows', white patches in the outer part of their wings."
Why am I receiving all these inquiries? Because eagles were completely extirpated from this region in the 1950s due to overuse of pesticides.
Before World War II, the south shore of Lake Erie was well known for its eagle nests. They had been publicized in National Geographic Magazine in articles by Oberlin professor Francis Herrick. One woodlot near Vermillion, Ohio was the site of eagle nests that were occupied by successive pairs for over 100 years. When one of those nests fell in a 1922 storm, it was estimated to weigh two tons. Herrick went on to band eagles at hundreds of nests in Ohio and later Florida.
Then along came widespread use of DDT. That poison had played an important role in World War II protecting our troops from disease-carrying insects. But now used without control for crop and human protection against problem insects, it moved up the food chain - especially through fish, eagles' primary food - to accumulate in the bodies of these predators. The most serious effect was the thinning of eagle eggshells. The shells became so delicate that they were crushed when the parents sat on them to keep them warm.
As one result, the 1980-85 survey of New York State breeding birds led by Robert Andrle, reported only two active eagle nests statewide.
Other toxins - PCBs, DDE, mercury and dioxin - cause problems similar to those caused by DDT, but the elimination of DDT together with restrictions placed on use of those other poisons gave the eagles a chance for a comeback.
Eagles at the nest
photo by Bob Johnson
And come back they have. They were assisted at first by game managers and birder volunteers. A number of young eagles were hacked, some of them at the Oak Orchard Wildlife Management Area. Hacking is technical jargon for carefully raising birds from eggs imported from regions where they had not been subject to so many toxins and released with as little human contact as possible. Eagle eggs were often brought from Alaska. Later, ospreys were similarly hacked, their eggs brought from Long Island.
But once started, the eagles began to make it on their own. By the time the statewide survey of breeding birds was repeated between 2000 and 2005, 124 eagle aeries were confirmed, a remarkable gain of 6100%. Now there are probably at least a dozen eagle nests here in western New York and nearby Ontario.
During migration, additional eagles pass through the region. As I write this in early April, 19 have already been counted this year at the Hamburg hawk watch. In the full season of 2009, 54 were counted there and 126 were reported that year at Ripley, 45 miles farther southwest along Lake Erie.
The return of the eagles has been a conservation success story and those many inquiries are just one more indication of that success.
One way to see eagles is to participate in one of the Iroquois Observations programs at the wildlife refuge. Eagles will be observed from the Cayuga Overlook on Route 77 the next two Saturdays between 1 and 4 p.m. This Saturday, Mike Allen will also talk about eagles at 1 p.m. at the refuge headquarters.-- Gerry Rising