– Steve Kolbe couldn't wait to step onto the Hawk Ridge overlook. He set up his spotting scope, grabbed his binoculars and kept a clicking counter nearby, then fixed his eyes on the skies.

After just a few minutes, he started spotting them.

"Here comes a nighthawk!" he exclaimed. "Oh yeah!"

The medium-sized birds approached in the distance from the north. First a few small groups, then larger ones. He counted them for more than three hours.

As an avian ecologist for the Natural Resources Research Institute at the University of Minnesota Duluth, Kolbe has been tallying the birds for the past five years, documenting what he and other experts believe is by far the world's largest concentration of migrating common nighthawks as they pass through Duluth on their way to South America.

Last year, Kolbe tallied a total of 40,000; one night alone he counted 14,000.

The next greatest concentrated migration of common nighthawks is in Florida, and it's only a few thousand a year, Kolbe said.

But the birds are on the decline, according to the Audubon Society and various other groups. The Minnesota Department of Natural Resources (DNR), for instance, has them listed as a "species in greatest conservation need."

The research institute, created by the Minnesota Legislature, is studying the birds as part of its mission to research aspects of the state's natural resources economy.

The first step in figuring out how to help them is developing a more informative survey method, said Alexis Grinde, wildlife ecologist and research program manager at the institute. The lead researchers hope to put together a citizen monitoring program around the state next year, asking other people to join in the bird counting.

But for now, Kolbe works the skies alone each evening, starting around Aug. 15 and finishing around Sept. 1. He eagerly awaits the nightly challenge of quickly counting the birds and entering the numbers, the weather and other conditions on a tablet computer.

Even from afar, Kolbe can spot the birds flying through in groups called kettles, their telltale traits of long angular wings, tilted flying patterns and white wing patches.

They are not, however, actually hawks, which are birds of prey with talons. Nighthawks are more closely related to whippoorwills in the nightjar family.

With big eyes and small, whiskered beaks, they like to nest on open ground or atop flat, gravelly roofs and make a short call that sounds like "meerp," Kolbe explained.

They typically lay low during the day, resting and blending in on tree branches, "then gorge on insects at night," he said.

"They don't do a whole lot wrong in the eyes of most people," Kolbe said. "They eat bugs and stay out of people's way."

But so many questions remain.

What are their requirements on their migration journey from Canada to South America? Why do so many fly through Duluth? Why are their numbers declining?

"They're sort of mysterious," Kolbe said.

Kolbe hopes his counts can lead to more research about the birds, which are rarely seen in such dense numbers.

"A big nighthawk night is just as rare as seeing a rare bird," Kolbe said.

"It's something to be savored."

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