For nearly six weeks in early spring, about 80 percent of the world's sandhill crane population funnels through Nebraska's Platte River valley en route to nesting grounds in the north.

For nearly six weeks in early spring, about 80 percent of the world's sandhill crane population funnels through Nebraska's Platte River valley en route to nesting grounds in the north.

Sometimes so many soar between sandbars and nearby fields that they block out the setting sun, said Jed Burtt, professor of ornithology at Ohio Wesleyan University.

Burtt and his wife saw about 250,000 cranes several weeks ago - and he's been spotting a few more since he got back home.

During the past several years, more sandhill cranes have been flying over and nesting in areas in Ohio that have worked to improve water quality, restore prairies and rebuild wetlands once drained for agriculture.

"I'm seeing them occasionally now, and that's more than 20 or 30 years ago," Burtt said. "I saw a small flock of them two weeks ago flying out the window at the science center."

Expanding sandhill populations have widened migration routes into western Ohio and set up breeding grounds as far south as Pickaway County. A pair recently returned to Slate Run Metro Park for the third straight year, this time with a third bird in tow.

"It's been a really neat success story to see them come back to Ohio," said John Watts, resource manager for the Metro Parks. "I remember in the mid '80s one showed up in Knox County - and it was pretty big news."

Pretty and impressive, this tall wading bird bears a bright red patch of exposed skin on its forehead and can have up to an eight-foot wingspan. Sandhills eat a variety of plants and animals and most often thrive in mature, healthy wetland complexes.

And they like to dance. During mating and apparently just to relieve stress, the birds often hop, spin, strut, bob, bounce, squawk and flutter their wings.

To meet the Slate Run trio, hike the Kokomo Wetland Trail in the early morning or at dusk and listen for a distinctive rolling, staccato call. Be as quiet as possible, because sandhills are standoffish and wary of people.

"A number of people are seeing them along the trail," Watts said. "A couple weeks ago, I could hear them from the parking lot."

Want to see other birds and wildlife? Find out where to explore at the Ohio Adventure Map at columbusalive.com/venture.