Kris Eilers spotted it even as she was putting up signs three weeks ago at Duluth's Park Point to try and protect it: a small gray and white bird, its neck and forehead banded in black, an orange beak, orange legs. A piping plover.

Now Eilers, her environmental group and Duluth city officials are hoping that the male plover, an endangered shorebird once plentiful around Lake Superior, and another male seen recently will stay long enough to mate with a female and nurture fledglings before leaving town.

To encourage the birds to nest at Park Point, the tip of a 7-mile-long sand spit that juts into the lake, volunteers are asking residents and visitors — especially those with unleashed dogs — to steer clear of a mile-long stretch of beach near Sky Harbor Airport through mid-June. That's the area where spotters saw the plovers.

Eilers said that a couple of people wandered into the area on Sunday, a warm but overcast day, but that most avoided it. There were few people on the beach Monday, which was rainy and windy.

One of the plovers was seen again last Tuesday, she said.

"There have been years that we didn't get reports of any stopping here, so even to see one is pretty special," said Eilers, project manager for the St. Louis River Alliance, a nonprofit that seeks to protect and restore the river. The habitat project is funded with a grant from the U.S. Fish and Wildlife Service.

"What makes this really unusual is that they've never hung around this long before," she said. "We've never seen one for more than a day, and we've never seen two."

It's been nearly 30 years since a pair of piping plovers nested in the Duluth area. Now the only breeding population on the western end of Lake Superior, consisting of six nesting pairs, is located on Wisconsin's Apostle Islands.

"That's why we're working on it, because historically they did nest here," Eilers said.

John Sargent, vice president of the Park Point Community Club, said that most residents backed the efforts of the river group to protect the birds.

"For visitors and those outside Park Point, I'm not sure," he said. "But the impact on people going to the beach is probably small."

Eilers said that they don't have authority to restrict access to the city-owned area where the plovers were seen. But city officials are cooperative, she said, letting them post signs and mark off "psychological fencing" to keep people at bay.

City ordinances require dogs to be leashed, but dog owners often let their pets off the leash on the beach.

There are three main populations of piping plovers in North America, located in the central plains, Great Lakes and East Coast regions. Only the Great Lakes birds are endangered, numbering 70 nesting pairs at last count.

Aside from natural predators, piping plovers are victims of habitat lost to human encroachment, Eilers said. They like to nest in the middle of wide beaches, where the male will scrape out a depression in the sand and line it with rocks. Females typically lay four speckled eggs, which are incubated by both partners.

Eilers said she is sure that females will show up; they usually see at least one, she said. Once the birds succeed in getting a nest in place, they try to return to the same area. But they won't touch the place if there are dogs or lots of people around.

Scientists and students in other parts of the Great Lakes, on both sides of the border, have been monitoring plover nesting areas for several years in an effort to build the population.

Kevin Duchschere • 651-925-5035