Endangered bird species and recovery

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By George Walter

In my more than 40 years of birdwatching, I have witnessed several astonishing recoveries of populations of prominent endangered bird species. Much of this recovery is the result of government regulation of practices that put them at risk.

During and after World War II, there was a major push to use insecticides to control mosquitoes and other insect pests. Perhaps some of you older readers remember the days when trucks equipped with foggers drove through the alleys to spray insecticides. The postwar expansion of the agricultural industry also used greater amounts of pesticides.

Do you remember DDT?

Dichlorodiphenyltrichloroethane (DDT) is perhaps the most widely used of these pesticides. Environmentalists have been concerned about the damage caused by these chemicals to animals that ate insects, especially birds. The impact was not direct poisoning; it was much more insidious.

DDT’s chemical compounds are relatively long-lived and bioaccumulate. This means that animals that ate insects – fish for example – increasingly absorbed the compound with which the insects had been sprayed. Birds that fed on these fish earned even more.

Researchers eventually learned that DDT inhibited calcium absorption in birds and led to eggshell thinning and nest failure.

silent spring

In 1962 Rachel Carson published her book, silent spring. He introduced the scientific evidence against DDT to general readers and helped generate a huge backlash against the widespread use of pesticides without first testing their safety. In 1970, Congress created the Environmental Protection Agency (EPA). In 1972, DDT was banned for agricultural use in the United States. In 1973, Congress enacted the Endangered Species Act (ESA), recognizing public (i.e. governmental) responsibility to assess the health of species and, where appropriate, develop recovery plans. for populations at risk.

bald eagles

When I started working for the Nisqually Tribe in the late 1970s, bald eagles were rarely seen. There was a single eagle’s nest in a remote location on the reserve and we would take visitors to this location where they might spot an eagle. And the rare times you could see a bald eagle flying overhead, it was a rare omen of good luck.

All that has changed in the last 40 years. Bald eagles are now common in the Nisqually River watershed and other locations in Thurston County. If you’re careful, you’ll likely see a bald eagle regularly when you’re out and about. And some years we have winter counts of 100 or more eagles on the river feeding on dead salmon after spawning (the natural end of their life cycle).

brown pelicans

When I started serious birdwatching in the late 1970s, brown pelicans were not seen on the Washington coast. Their breeding numbers and success in California had drastically declined, and they were listed by the ESA. Now every summer we see hundreds of brown pelicans along the coast. They migrate north after breeding, feeding on summer concentrations of small fish. When you are on the coast from August to October, you will undoubtedly see small flocks of pelicans arching above the waves.

peregrine falcons

A third success story is that of the Peregrine Falcon, a fast-flying bird that feeds on other birds. These falcons also suffered from reproductive failures and were rare in our area in the late 1970s and early 1980s. All of that changed with the DDT ban, and little by little this species recovered. . In fact, before they were removed several years ago, one of the cranes in the port of Olympia housed a nesting pair of peregrine falcons. It seems that they particularly liked to prey on rock pigeons.

In summary, the birds we enjoy now were endangered and rare in the past. Whenever you hear someone attacking the EPA or ESA or bashing government regulations in general, I hope you’ll think of those success stories. Regulations and their enforcement have saved these birds and their critical habitats. They are vital to the natural world which we all benefit from.

George Walter is Environmental Program Manager in the Natural Resources Department of the Nisqually Indian Tribe; he has also been interested in bird watching for over 40 years. It can be attached to [email protected]

The photos in this column are provided by Liam Hutcheson, a 15-year-old Olympia-area birdwatcher and avid photographer.

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