Watching sandhill cranes gather in autumn
By the early 1900s, the wholesale slaughter of sandhill cranes had greatly reduced their numbers in Wisconsin, causing famed naturalist Aldo Leopold to grieve that these stately birds would soon go the way of the passenger pigeon, which was exterminated by unregulated hunting.
But with the passage of the Migratory Bird Act of 1916 and the Migratory Bird Act Treaty of 1918, the sandhill crane population began to slowly rebound.
But hunters continued to stalk the birds, known as the “ribeye of the sky,” said Stanley Temple, a retired University of Wisconsin-Madison professor who leads sandhill crane tours on the Wisconsin River.
“Unfortunately, people didn’t stop shooting the cranes the minute the law was passed,” Temple said.
The birds can grow to 4 feet tall, have wingspans of nearly 8 feet, weigh up to 9 pounds and have a distinctive call that can be heard from up to 2.5 miles away.
In Leopold’s 1937 essay, “Marshland Elegy,” he lamented the loss of wetland habitat and worried that the last crane would soon “trumpet his farewell and spiral skyward.”
He had good reason, for in his surveys, he found only a few dozen surviving sandhill cranes in the Badger State. By the time of his death in 1948, those numbers were still low, said Temple, who is a senior fellow at the Aldo Leopold Foundation near Baraboo.
“Sadly, he died well before the sandhill cranes had recovered,” Temple said. “In the late ’40s, there were only several thousand of them stopping at the Jasper-Pulaski Wildlife Area in northern Indiana on their way south to their wintering grounds.”
But rebound they did, Temple said, and the recovery of these birds is one of the great conservation success stories of the 20th century.
Much of that story is taking place on the landscapes near the shack and farm that Leopold made famous in his tome, “Sand County Almanac,” said Temple, a Beers-Bascom professor emeritus in UW-Madison’s Department of Forest and Wildlife Ecology, the same position Leopold once held.
Every year in the late fall, as many as 10,000 sandhill cranes gather on sandbars and islands in the Wisconsin River. They spend several months dining on corn leftover in farm fields in the area before flying south.
“It really is something of a coincidence that the area behind his shack provides both a safe place for them to roost at night and lots of waste grain remaining in fields from the harvest for them to eat,” he said.
“Furthermore, one of the largest concentrations of nesting cranes isn’t too far to the north, so it’s a relatively easy hop, skip and a jump to get to the river and join the other cranes there. Only a couple of hours flying time and then they are on the river behind Leopold’s shack.”
Temple said it wasn’t until the late 1960s and early ‘70s that the numbers of sandhill cranes had reached what he called a “critical mass” to ensure their continued survival.
“Because they reproduce so slowly, it took a long time,” he said.
They now number about 100,000 in the eastern United States and Canada, with perhaps half that number living in Wisconsin, he estimated.
Temple said the cranes are highly territorial and spend the summer in widely dispersed territory that they vigorously defend against intrusion by other cranes.
“It is pair-by-pair and they have exclusive areas,” he said.
But during the late summer and fall, the extreme territoriality they exhibit during the nesting season starts to break down and they begin to hang out with neighbors, he said.
“Eventually, they join large groups of birds at these traditional staging areas and stay until the water freezes over and snow covers the fields,” he said.
In addition to the land near the Aldo Leopold Foundation, thousands more birds roost near Arena on the Wisconsin River and as many as 10,000 have been counted at the Crex Meadows Wildlife Area near Grantsburg in northwestern Wisconsin.
Temple, who earned his doctorate in vertebrate zoology and ecology from Cornell University in New York, said he began to focus on sandhill cranes soon after he arrived at UW-Madison in 1976.
“When I was an active faculty member and researcher, my graduate students and I did some of the pioneering work on radio tracking these birds on their migration,” he said. “We basically wrote the book about sandhill cranes’ migration strategies, using radio tracking to follow them from their nesting to wintering areas, which allowed us to eavesdrop on them 24/7.”
He said the birds typically spend their winters on the Gulf Coast and in Florida, though the warming climate means some are no longer going as far south.
Temple said hunters have been allowed to shoot lesser sandhill cranes, which fly south from the Arctic and congregate along the Platte River in Nebraska, since the 1970s.
“A limited number of permits are given to hunt these birds, and that’s now happening with our sandhill cranes in Tennessee and Kentucky,” he said.
“As soon as the U.S. Fish and Wildlife Service said the population was large enough to sustain itself, those states applied and they now shoot several thousand of them a year between the two of them.”
In Wisconsin, a similar effort to resume hunting sandhill cranes has so far been unsuccessful, he said.
“Some of our legislators are dead set on catering to their rural hunting voters by giving them more and more things to hunt,” he said. “But there has been a significant pushback from people who don’t regard cranes as a game bird and haven’t for many, many years. So far, that pushback has been strong enough so legislators have backed off.”
As a scientist, Temple acknowledges there is no biological reason not to hunt sandhill cranes, though he said there are other reasons to oppose the change.
“We have a small and slowly growing population of whooping cranes, and I worry that hunters might mistake and shoot them if there were a sandhill season,” he said.
“And there’s also the ethical question,” he said. “Just because you can kill something doesn’t mean you should. Even though they might be able to be hunted in a responsible way, I think continuing the ban is the right thing to do in Wisconsin.”
More information: The Aldo Leopold Foundation offers public tours of cranes from 2:30 to 5:30 p.m. on Fridays and Saturdays through December. Tours cost $75 and include a wine and cheese reception. Tours often sell out in advance.
The foundation also has photography blinds visitors can rent for $150 and will begin offering private overnight tours ($250/person) in 2018.
For more, see aldoleopold.org or call
(608) 355-0279.
Getting there: The Aldo Leopold Foundation, E13701 Levee Road, Baraboo, is 115 miles west of Milwaukee via I-94, I-90 and Highway 33.