Harvey Webster and friend

Despite the enormous impact human development has had on the natural landscape of Ohio, many species of birds are thriving in urban areas, said Harvey Webster of the Cleveland Museum of Natural History. But not all species have been able to adapt, and the continual evolution of the urban landscape will provide both opportunities and perils to the birds that live among us.

Webster’s remarks were delivered in an evening lecture last night at the Natural History Museum, where he is the museum’s Chief Wildlife Officer. His talk was part of the museum’s Explorer Lecture Series.

In Northeastern Ohio – as in almost everywhere else – the natural landscape is continually evolving in ways that either support or fail to support wildlife, said Webster. Birds – and other animals – are forced to adapt to these changes. The birds and animals that we see in our urban and suburban areas today have adapted successfully. If a species could not adapt, we simply don’t see it around.

The evolution of Ohio’s physical landscape opens new opportunities for wildlife to reclaim previous territory or to populate new territory.

An obvious example is the white-tailed deer. No one knows how many deer lived in Ohio in the years before European settlement. But it is known that by 1908, deer were effectively eradicated in the state. But in the 1920’s and 1930’s deer were reintroduced and by 1956 they could once again be found in all Ohio counties.

Four bird species that have adapted especially well to Ohio’s human-dominated landscape are gulls, hawks, falcons, and turkeys, said Webster. All are thriving in urban settings. Other birds that have adapted well and are regularly seen in Ohio include ospreys, turkey vultures, Canadian geese, and bald eagles. Currently there is a nesting pair of eagles along the Towpath Trail in Cleveland and another pair at a playground in Avon, Webster said.

Hawks do especially well in areas where people have erected backyard feeding stations for songbirds, said Webster. “We put out food to attract birds, because we like them,” said Webster. “But so do hawks.” While the hawks undoubtedly appreciate our efforts, we really don’t need to put out food for songbirds, said Webster. “They do very well without the feeding stations.”

Birds look for ways to exploit opportunities in the landscape, said Webster. Ospreys commonly nest on cell phone towers while turkey vultures roost there.

But while many species have adapted well to life near humans, some features of the urban landscape are devastating for birds, especially for migrating birds. And that’s a lot of birds. Each year in the United States, six billion birds migrate north, while 8.7 billion migrate south. Some migrations are truly epic.

Several species of warbler – a family of songbirds that usually weigh less than half an ounce – migrate from Ohio to winter feeding grounds in Mexico, the West Indies, or South America. One species, the Blackpoll Warbler, migrates a preposterous 2,000 miles over open ocean from its breeding grounds in Canada to its wintering grounds in Venezuela. At an average speed of 25 mph, the non-stop flight takes up to 88 hours. During the flight, each warbler loses about twenty percent of its body weight. Birds that did not gain enough weight in preparation do not survive.

No one is exactly sure how the warblers manage to find their way across the sea, but research indicates that they, along with many other migrating birds, navigate using the stars, the sun, and the Earth’s magnetic field. Scientists do know that the warblers fly to the coast where they wait for favorable winds to start their journey.

While warblers have to fly night and day to complete their ocean crossing, many bird species migrate primarily at night. This keeps them safe from predators, but leaves them vulnerable to a modern hazard: lighted buildings. Migrating birds use the stars to orient themselves during their flights. But on cloudy or foggy nights when the stars are not visible, they can become disoriented by building lights and crash into the building or circle it until they fall from exhaustion. A recent study estimated that as many as half a billion birds are killed in collisions with buildings each year in North America.

To reduce the number of migrating birds killed in building strikes, the Cleveland Museum of Natural History partners with the Ohio Bird Conservation Initiative on a program called ‘Lights Out Cleveland,’ which works with building owners to adjust their building lighting during peak migration periods to reduce bird strikes.

Lighted buildings aren’t the only hazards for birds, noted Webster. Wind turbines, power lines, towers, vehicles, and plate glass windows all take a toll. And, of course, cats. Each year hundreds of millions of birds are killed by cats in America, said Webster. “This is a significant source of mortality,” he said. “Something we could easily stop.”

Cat owners should take responsibility for their pets, he said, by keeping their cats indoors. Other actions that anyone can take to help reduce mortality of birds include placing bird tape on windows, volunteering with a bird-supporting organization, creating a mini-habitat or refuge, and planting native plants in your yard.

April 13, 2019