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Black, red or dead: How Omaha became a hub for black squirrel scholarship

2024-12-19 01:03:00 新闻中心

Three taxidermied penguins preside over Room 426 in Allwine Hall, standing atop a row of metal cabinets in the back corner.

The Antarctic birds are locked in an everlasting staring contest with a stuffed hornbill whose craned neck protrudes from a bookcase holding a row of primate skulls.

To the students who file into professor James Wilson’s mammalogy class, these are ordinary sights.

What grabs their attention on this Monday afternoon are the short stacks of paper spread neatly across the black lab tables.

Today they are receiving an unusual homework assignment with straightforward instructions: fan out across the Omaha metro area and count squirrels.

The squirrel census undertaken by Wilson’s students at the University of Nebraska at Omaha has become an annual fall tradition over the past 15 years.

Walking or driving slowly down their assigned streets, the aspiring biologists tally all the squirrels they see, whether black, red or dead. Their surveys have fueled Wilson’s research and built on UNO’s legacy as a hub of black squirrel scholarship.

Nearly all of the squirrels living in the Omaha area belong to the same species — the fox squirrel — but a genetic mutation causes some to produce a lot of melanin, making their fur black rather than the usual reddish-brown, Wilson said.

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Black squirrels exist in urban pockets across North America, but they have long enjoyed celebrity status in Council Bluffs, Iowa, where they make up roughly half of the local squirrel population. A black squirrel named Chipper serves as the city’s mascot, and a decades-old ordinance makes it illegal “to annoy, worry, maim, injure or kill” the rodents.

They used to be rare in Omaha, but Wilson’s analysis found that the critters have become more plentiful and expanded their paw print westward. Humans and the bridges they’ve built likely had something to do with that, he said.

The long-running study has helped local biologists learn more about the region’s multicolored squirrel population, while providing students meaningful fieldwork close to campus.

Brett Andersen, who took Wilson’s class in 2013, reflects on the assignment as his first taste of the hands-on research he aspired to do from a young age. Now, he’s got a dream job working with at-risk species for the Nebraska Game and Parks Commission.

“You never expect that to be the first thing that’s going to kick-start your career, and yet here I am and I get to point back to that,” Andersen said.

Counting squirrels may seem like a trivial activity, but a decade down the road, having baseline information about the population could be really useful, Andersen said. He noted that monarch butterflies used to be plentiful, but they’re now one of the endangered species he’s monitoring.

“Even with common things, it’s still valuable to look at how they’re doing,” Andersen said.

Becoming part of the scenery

Peering out the passenger side window of a slow-moving sedan, Bella Madsen scanned front yards, trees and sidewalks for movement.

“There’s one!” she excitedly exclaimed as a red squirrel darted across a west Omaha lawn.

The senior biology major said taking a few hours to count squirrels helped her think more intentionally about the flourishing urban wildlife around her.

By the end of her survey, Madsen tallied 24 squirrels — only one of them black.

But a surveyor would’ve been hard-pressed to find any black squirrels in what is now Omaha a few centuries ago.

In 1843, John James Audubon encountered several black squirrels along the eastern edge of the Missouri River between St. Joseph, Missouri, and Council Bluffs, according to his journal entries. He never recorded seeing any along the west bank of the river.

The famous naturalist, known for his depictions and descriptions of American birds, misjudged the dark-colored rodent, believing it to be a distinct species.

A colleague dubbed the animal “Sciurus audubonii” in honor of Audubon’s son, but biologists later tossed the name after discovering it was merely a different shade of the common fox squirrel.

Ed Lueninghoener took a more scientific approach to studying the peculiar creatures.

A meticulous “spot count” he performed in Council Bluffs as a UNO graduate student found a nearly even split between black and red squirrels, according to his 1973 master’s thesis. His poll of conservation officers revealed that black squirrels were “present in small numbers” on the Nebraska side of the river.

Wilson came across the thesis shortly after joining UNO’s biology department in the late 2000s. The Southern California native had studied rodents for several years, and he thought it would be interesting to pick up where Lueninghoener left off. Plus, he saw black squirrels as “super cute.”

“Omaha is a great city, but it is eight hours from anywhere wild,” Wilson said. “It’s a good local thing to do more research on.”

The first study Wilson authored on the area’s squirrels in 2013 found that black squirrels made up about 7.5% of the total squirrel population in the northern half of Omaha and roughly 4.5% in the city’s southern half.

Wilson doesn’t know exactly how black squirrels arrived in Nebraska, but he suspects humans played a central role in growing the population. The agile tree dwellers could easily cross the river on bridges or in tow with an unbeknownst driver.

Hunters or black squirrel aficionados may have brought them over deliberately, he noted. Red and black squirrels also can breed together, sometimes creating offspring with mixed fur colors.

The professor has observed black squirrels as far afield as Lincoln, and he’s heard anecdotally there are some in other eastern Nebraska cities.

The 2013 findings prompted Wilson to ponder why black squirrels were growing in proportion. Could they have some kind of biological advantage over their red counterparts?

UNO grad student Amanda Ciurej measured the surface temperature of Omaha squirrels with an infrared thermal gun to see whether having light-absorbing dark fur helped the black ones stay warm in chilly weather.

A 2019 study co-authored by Ciurej found that black squirrels “may have a slight winter thermal advantage” over red ones, allowing them to conserve energy and gain foraging time in colder months.

Wilson hopes to turn the last decade of student-collected data into a follow-up paper. He expects to find a continued trend of black squirrels expanding in Omaha.

He intends to focus further squirrel studies on how people perceive and interact with the animals. He wonders whether humans give preferential treatment to black squirrels because they view them as special or cute.

A few years ago, Wilson asked students to start recording the color of any dead squirrels they came across during their surveys. That data could help determine whether drivers are more likely to avoid running over black squirrels.

He’s also curious about whether humans are more inclined to feed black squirrels that show up in their neighborhood.

Andrew Hubbard admires the black squirrels in his backyard as a fascinating novelty, but he’s an equal-opportunity feeder.

“I love all our squirrel babies,” he said.

The Millard resident started giving peanuts to the squirrels a dozen years ago. He switched to trail mix when his bushy-tailed congregation grew.

But Hubbard’s “squirrel obsession really ramped up” during the COVID-19 pandemic when he began buying 3-pound bags of walnuts at Costco and “watching them for hours on end at the kitchen window.”

The Union Pacific consultant now gets 5-10 regular diners on his patio every morning. (Wildlife experts generally discourage feeding squirrels and other wild animals. Hubbard said he sometimes worries about his impact on the ecosystem.)

Even though Hubbard feeds squirrels indiscriminately, he thinks Wilson’s question about black squirrel favoritism is valid, noting that hunters might not kill an albino deer because of its rare beauty.

One black squirrel has burrowed deeper into Hubbard’s heart than all the others — but not because of his color.

Seemingly the runt of the litter, he started coming around to eat as a kit in 2021. Hubbard noticed he was missing a foot and named him “KickAss” — a reference to the saying busy as “a one legged man in an ass-kicking contest.”

KickAss never grew to the size of his comrades, and he lost patches of fur twice a year due to some kind of mange or flea infestation, Hubbard suspects. The other squirrels picked on him, often nipping at his tail.

Despite his misfortune, KickAss persevered. But now Hubbard hasn’t seen his friend in a few months. He fears KickAss may have crossed “the squirrel rainbow bridge.”

“He’s just so resilient. It sounds so stupid to say this, but for a squirrel, he’s like so inspiring,” Hubbard said. “I miss him a lot. I keep praying that he’ll come back around.”

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This story was originally published by Flatwater Free Press and distributed through a partnership with The Associated Press.

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