BIG HORN — Before flocks of tourists descend on Sheridan County for myriad summer events, another flock of visitors swoops in and sets up summer homes in some of the area’s prime real estate with views of the Bighorn Mountains and good eating nearby.
These visitors arrive like clockwork around March 17 and stay through August. Snowbirds of sorts, they then make the long journey back to Bosque Del Apache National Wildlife Refuge near Socorro, N.M.
It is the first 800-mile flight to Bosque for the baby sandhill cranes — called colts — that call places like The Brinton Museum, Parkman and Soldier Creek their birthplace. In fact, the colts that are born here will return to their Sheridan County summer home for the rest of their relatively long lives.
Once a Wyomingite, always a Wyomingite, it seems.
“What’s interesting about cranes is they have a lot of site fidelity and family fidelity. They have the same mate for their lifespan, which in the wild is very different than in captivity, so maybe 13, 14, 15, 20 years. And it’s the same pair,” Sheridan College Professor of Anatomy and Physiology Jackie Canterbury said.
Canterbury and several members of the Big Horn Audubon Society ventured out Saturday to The Brinton Museum to see if they could spot the tall, lanky visitors that have settled into the wetlands near the museum. There is at least one known pair of greater sandhill crane that reside near The Brinton.
Several other pairs have also been spotted around Big Horn, along Upper Road, in the Soldier Creek area and near Parkman. In fact, Canterbury said she spotted approximately 35 cranes near Parkman on Sunday.
“These are the Rocky Mountain Sandhill Cranes, and the population is thought to be about 20,000, generally. We have quite a few breeding pairs here, but nobody knows. There haven’t been really good surveys, and that’s kind of what this group is doing, hopefully, is looking to see how many pairs we have and where they are,” Canterbury said.
This week, the cranes will be feeding in the lands around their nesting areas to replenish their fat supply that was diminished over the flight to Wyoming, so it is a good week to try to spot the visitors. Canterbury said to remember to be quiet and keep a safe distance when viewing.
By early April, the cranes will begin to breed and need to be left alone, Canterbury said, discouraging treks to spot sandhill cranes during the breeding and fledgling season which lasts from April through mid-July.
The breeding ritual involves an elaborate dance and unison call that the pairs use to re-establish their couple status, much like a yearly renewal of vows, Canterbury said.
Typically, each pair lays two eggs, and they take turns incubating them for 30 days. The larger male sits on the eggs overnight, and then the female crane sits on them through the day. They changeover incubation duties like clockwork at about 7:30 a.m. and 7:30 p.m.
Once the eggs hatch, the colts enter a 70-day fledgling period. The incubation and fledgling period are a vulnerable time for the young birds who are in danger from snapping turtles, foxes, coyotes and other predators. Often only one of the two colts make it through the summer, Canterbury said.
The fledgling period is a time of learning and bonding. Parents transfer critical information about geography, safe foraging sites and roosting sites to their colts.
“They’ll teach the colt how to fly, how to dance, how to call. It’s pretty amazing. And then they’ll teach the colt how to fly and the route back. So the family bond is very incredible because it’s teaching and learning,” Canterbury said.
Canterbury said each family has its own call so that they can locate each other during migratory flights. She also said the strong family bonds make hunting — which is allowed in Wyoming — detrimental to the crane population.
The sandhill cranes stay in the area through August.
“Six months are spent here, so half their life cycle. This is a really important place for them,” Canterbury said.
On Saturday, no cranes were spotted by the group. But they did see a great blue heron and a herd of elk through their binoculars. And they enjoyed a quiet morning hushed by a fresh coat of snow, shrouded in mist, with the sense of anticipation birdwatching brings.
“The magic of birdwatching is not necessarily finding the bird. It’s exploring. It’s curiosity, and it’s learning about where they might be at one time,” Canterbury said. “When you go out, like today, we didn’t see the cranes, but I know they’re around, so it gets my heart pumping about thinking where they are. When you do find them, it’s just magic.”
• There are two races of sandhill cranes in Wyoming: the lesser sandhill crane migrates through the eastern plains and the greater sandhill crane nests in montane meadows and wetlands in the Bighorn Mountains.
• Cranes typically lay two eggs and incubate them for 30 days.
• The cranes that come to Wyoming most likely winter along the Rio Grande River in New Mexico.
• Cranes form permanent pair bonds after two to three years of maturing.
• Sandhill crane flocks can number in the thousands.
• Colts born in the summer begin to shed their gray crown feathers the next spring to reveal bare red skin that is vital for communication. At that time, the colts’ voices begin to change from a high-pitched whistle to a lower, more throaty note as their windpipes lengthen.
• Cranes reach heights of 2.5 to 4 feet tall and weigh 9-10 pounds when full grown.
• The trumpet call of cranes sounds like a French rolled ‘R’ sound.
• The Rocky Mountain Sandhill Crane population is estimated at 20,000-30,000 but little is known about population size and trends in Wyoming.
Catch local bird expert Dr. Jackie Canterbury and her mentor and crane expert Dr. Paul Johnsguard on a TV special about the sandhill cranes on the Platte River in Nebraska during the CBS News Hour tonight.