Some of North America's tallest birds have been making short stops in North Dakota lately.

At least three confirmed sightings of whooping cranes, the endangered birds that are migrating from Canada to Texas, were reported Tuesday.

One whooping crane was seen in the air Monday west of Kenmare, two whoopers were spotted Sunday morning in southeastern Emmons County and two adults were spotted Saturday nine miles south of Ryder in Ward County - and probably again Monday three miles west of the Saturday sighting.

Will Meeks, the manager at Lostwood National Wildlife Refuge, saw the lone whooper at about 11 a.m. Monday about 17 miles west of Kenmare, which is in northwestern North Dakota.

"It was flying with a group of sandhills," Todd Frerichs, the Lostwood NWR wetland district manager, said Tuesday. The speculation was that the whooper was roosting near the refuge and had joined the sandhill cranes when they flew off to feed. But no other sightings of the bird had been reported Tuesday, said Frerichs, who sent in the report.

The Emmons County whoopers were on the ground northwest of Hague. Ron Maier, a state Game and Fish Department game warden based in Linton, said he saw the whoopers at about 10 a.m. and watched them for about an hour.

"Then they decided to leave. They lifted up in the air, sailed around and around, got altitude and were gone," he said Tuesday. "Hopefully, they're headed to Texas."

Chad Klindtworth, a private lands biologist at Audubon National Wildlife Refuge, first saw a group of sandhill cranes on Saturday evening. "Then I noticed two white ones," he said. "It's kind of exciting just because there are so few of them."

Whooping cranes are flying from their summer breeding grounds at Wood Buffalo National Park in Canada's Northwest Territories to the saltwater marshes of the Aransas National Wildlife Refuge on the Texas Gulf Coast, where they will spend the winter.

The latest whooper count from Wood Buffalo, done in August, puts the flock at between 210 and 212 birds, including 28 chicks. In April, 184 whooping cranes departed Aransas NWR for the trip north, said Vicky Bradshaw at Aransas NWR.

The increase in whooper numbers is good news for the endangered species. Whooping cranes living in the wild number 318, said Wally Jobman, a U.S. Fish and Wildlife Service biologist in Nebraska and the coordinator of the migration monitoring project for the Wood Buffalo-Aransas flock. Counting those in captivity, there are approximately 452 whoopers.

But Jobman isn't expecting all of the Wood Buffalo-Aransas flock to make it to the Gulf Coast.

"We always lose birds during migration," he said. "It depends on what the losses are and what the survival is for young birds. It's quite stressful for young birds flying from Canada to Texas.

"I'm hoping we can break 200 (reaching Aransas NWR)."

Despite a report of a whooper in Oklahoma, Jobman said no whooper sightings have been confirmed south of North Dakota. The Oklahoma report turned out to be an egret, Jobman said.

Gregg Knutsen, a biologist at Long Lake NWR near Moffit, said the peak of North Dakota's whooper migration is still to come.

"For the last few years, it seems like the last week of October was the biggest week for sightings," he said.

Klindtworth said he guessed the whoopers he saw Monday morning were the same two he saw Saturday. They were alone Monday, he said.

Maier was doing his routine patrol about 3/4 mile west and one mile north of Hague.

"A farmer came up and said 'look at that.' I said 'oh my goodness.' They are quite a bird."

Whooping crane sightings can be reported to Long Lake NWR at 387-4397, the state Game and Fish Department's office in Bismarck at 328-6300 or to local game wardens around the state.

Whooper sightings can be confirmed only by someone with Game and Fish, USFWS or a highly credible birder, Knutsen said. "Typically, we compile all the information, and if we can, we get someone out there to make a positive I.D."

Whoopers stand about 5 feet tall and have a wingspan of about 7 feet. They are white with black wing tips, which are visible only when the wings are spread. In flight, whooping cranes extend their long necks straight forward, while their long, slender legs extend behind the tail. Whooping cranes typically migrate alone or in small groups.

"To get a confirmed sighting is hard to do," Maier said, "but when you see them, there's no doubt what they are. There's no doubt."

(Reach reporter Richard Hinton at 250-8256 or outdoors@bismarcktribune.net.)