The Great Squirrel Migration of 1968

In the fall of 1968, people in the eastern United States experienced a force of nature unlike anything they’d seen before: grey squirrels, en masse, moving by the thousands out of the woods, crossing mountains, rivers, and highways.

Newspapers published accounts of squirrels swimming across—and often drowning in—bodies of water. In some locations, conservation officers reported picking up road kill at a rate of one squirrel per mile. Starvation killed many more.

Where were they all going? And why?

The explanation for this furry migration turned out to be simple: The animals had run out of food. After a bountiful year for acorns and chestnuts in 1967, the squirrel population ballooned. When this was followed by a poor season for these nut-bearing trees, the squirrels were faced with no choice but to search for more fruitful forests.

The most complete account of the migration comes from a wildlife biologist named Vagn Flyger, who at the time was a budding squirrel expert and game officer for the state of Maryland. According to his paper, "The 1968 Squirrel 'Migration' in the Eastern United States" [PDF], Flyger was first contacted by a colleague who drove from Maine to Maryland on September 13 that year and noticed an unusually high number of road-killed squirrels on the highway. Within a week, Flyger was also contacted by the Smithsonian’s Center for Short-Lived Phenomena (yes, this was a real institution, and itself short-lived, operating only from 1968 to 1975), which had been tracking news reports from North Carolina.

There were hotspots of activity elsewhere. The New York State Conservation Department collected 122 specimens on highways near Albany and received reports of dozens of them drowned in the Hudson. A September 28 article in the Journal News in White Plains was alarmingly titled "Squirrels Invading Lower Hudson Valley." In an article published October 6 in The Tennessean, the state’s fish and game commissioner Bob Burch marveled at the “almost unbelievable number of squirrels,” and informed the public the bag limit has been raised “from six to twelve bushytails per day” in order to “aid the hunter in keeping this valuable resource from being wasted.”

But North Carolina appears to be the epicenter. The Asheville Citizen Tribune, in a September 17 article headlined "Starvation, Cars, Killing Squirrels by the Thousands" reported on a wildlife resources commission meeting in which regional managers from across the state painted a gory picture. One, near Waynesville, described squirrels “pouring” out of the Smokies and swimming across Fontana and Cheoah Lakes. Another claimed he counted 40 dead squirrels on a roughly 20-mile stretch of road near Asheville. The story, "Squirrels Starving in Smokies’ Area," was even picked up by The New York Times on September 22.

In his paper on the investigation (published for the Natural Resources Institute), Flyger described driving to North Carolina and, with the help of a small team “dispatched” by the University of Georgia, setting up a “laboratory” in a motel room in Boone to examine specimens that had been shot by game wardens and picked up off highways.

The autopsies showed nothing unusual. There were no indications that the squirrels were heading in a specific direction—say, north, or west. However, Flyger learned, “based on discussions with many individuals as well as upon my own observations,” there had been a bumper crop of acorns in 1967, resulting in a corresponding bumper crop of baby squirrels in 1968. By autumn, as the first litter of the year left the nest, they found not enough food to go around.

Flyger’s theory holds up today, according to John Koprowski, renowned squirrel expert and a professor and associate director of the School of Natural Resources and the Environment at the University of Arizona.

“When you have a good year of chestnuts, it is a pretty massive amount of food, but when you have a bad year you don’t have that food source. So you can imagine animals moving around—especially when you didn’t have as many roads, and forests were continuous,” he tells mental_floss.

Koprowski points out that what happened is not an example of a true migration, but rather an emigration—“a one-directional movement out of a place.”

“It is a strategy of last resort, most likely,” says Koprowksi. “It really does appear to be a response to local conditions.”

As it turns out, 1968 wasn’t the first time that, prompted by scarce resources, grey squirrels had suddenly moved by the thousands. After reading Flyger’s paper as an undergraduate student at Ohio State, Koprowski dug into the phenomenon further and found evidence of similar—and even larger—squirrel emigrations in the 19th century.

In Texas in 1857, for example, a devastating mid-spring cold snap killed off crops and vegetation across the state, including newly budded nut trees, prompting a squirrel exodus. In one account, a young man named Henry Garrison Askew, traveling by horse and carriage near Dallas, described the horses being spooked by a disturbance in the tall prairie grass. He and his family watched in disbelief as thousands of squirrels crossed the road—some of them right over the horses and through the carriage— in a column that reportedly took a half hour to pass.

John Bachman, in an 1846 book called Viviparous Quadrupeds of North America, describes squirrel emigrations of that era in which squirrels would “congregate in different districts of the far Northwest, and in irregular troops bend their way instinctively in an eastern direction. Mountains, cleared fields, the narrow bays of our lakes, or our broad rivers, present no unconquerable impediments. Onward they come, devouring on their way everything that is suited to their taste, laying waste the corn and wheat-fields of the farmer … ”

Koprowski says these superlative-filled historical accounts don’t offer a clear picture of numbers. “They were often filled descriptors like marvelous or incredible … but not as quantitative as we would be now.”

It’s likely, Koprowski says, that numbers in the hundreds of thousands or even millions would have been possible, given the landscape at the time. “It's really hard for us to appreciate the amount of food that was there, and the density of squirrels,” he says.

Is it possible to have emigrations of those kinds again? Likely not, says Koprowski. “One, we’ve changed the forests pretty dramatically, with how we’ve fragmented them,” he points out. “There simply isn’t as much habitat for squirrels, or for nut-producing trees that they have historically depended on.”

But it’s fun to imagine. “It’s such a different kind of phenomena,” he says. “You're like, ‘Wow that's pretty neat.’”

Everything You Ever Wanted to Know About Dogs

Dogs: They’re cute, they’re cuddly … and they can smell fear!

Today on Scatterbrained, John Green and friends go beyond the floof to reveal some fascinating facts about our canine pals—including the story of one Bloodhound who helped track down 600 criminals during his lifetime. (Move over, McGruff.) They’re also looking at the name origins of some of your favorite dog breeds, going behind the scenes of the Puppy Bowl, and dishing the details on how a breed gets to compete at the Westminster Kennel Club Dog Show.

You can watch the full episode below.

For more episodes like this one, be sure to subscribe here!

Sploot 101: 12 Animal Slang Words Every Pet Parent Should Know

For centuries, dogs were dogs and cats were cats. They did things like bark and drink water and lay down—actions that pet parents didn’t need a translator to understand.

Then the internet arrived. Scroll through the countless Facebook groups and Twitter accounts dedicated to sharing cute animal pictures and you’ll quickly see that dogs don’t have snouts, they have snoots, and cats come in a colorful assortment of shapes and sizes ranging from smol to floof.

Pet meme language has been around long enough to start leaking into everyday conversation. If you're a pet owner (or lover) who doesn’t want to be out of the loop, here are the terms you need to know.


You know your pet is fully relaxed when they’re doing a sploot. Like a split but for the whole body, a sploot occurs when a dog or cat stretches so their bellies are flat on the ground and their back legs are pointing behind them. The amusing pose may be a way for them to take advantage of the cool ground on a hot day, or just to feel a satisfying stretch in their hip flexors. Corgis are famous for the sploot, but any quadruped can do it if they’re flexible enough.


Person holding Marnie the dog.
Emma McIntyre, Getty Images for ASPCA

Unlike most items on this list, the word derp isn’t limited to cats and dogs. It can also be a stand-in for such expressions of stupidity as “duh” or “dur.” In recent years the term has become associated with clumsy, clueless, or silly-looking cats and dogs. A pet with a tongue perpetually hanging out of its mouth, like Marnie or Lil Bub, is textbook derpy.


Cat laying on desk chair.
PoppetCloset, Flickr // CC BY-NC-ND 2.0

If you’ve ever caught a cat or dog poking the tip of its tongue past its front teeth, you’ve seen a blep in action. Unlike a derpy tongue, a blep is subtle and often gone as quickly as it appears. Animal experts aren’t entirely sure why pets blep, but in cats it may have something to do with the Flehmen response, in which they use their tongues to “smell” the air.


Mlems and bleps, though very closely related, aren’t exactly the same. While blep is a passive state of being, mlem is active. It’s what happens when a pet flicks its tongue in and out of its mouth, whether to slurp up water, taste food, or just lick the air in a derpy fashion. Dogs and cats do it, of course, but reptiles have also been known to mlem.


Very fluffy cat.
J. Sibiga Photography, Flickr // CC BY-NC-ND 2.0

Some pets barely have any fur, and others have coats so voluminous that hair appears to make up most of their bodyweight. Dogs and cats in the latter group are known as floofs. Floofy animals will famously leave a wake of fur wherever they sit and can squeeze through tight spaces despite their enormous mass. Samoyeds, Pomeranians, and Persian cats are all prime examples of floofs.


Dog outside barking.

According to some corners of the internet, dogs don’t bark, they bork. Listen carefully next time you’re around a vocal doggo and you won’t be able to unhear it.


Shiba inu smiling up at the camera.

Speaking of doggos: This word isn’t hard to decode. Every dog—regardless of size, floofiness, or derpiness—can be a doggo. If you’re willing to get creative, the word can even be applied to non-dog animals like fennec foxes (special doggos) or seals (water doggos). The usage of doggo saw a spike in 2016 thanks to the internet and by the end of 2017 it was listed as one of Merriam-Webster’s “Words We’re Watching.”


Tiny kitten in grass.

Some pets are so adorably, unbearably tiny that using proper English to describe them just doesn’t cut it. Not every small pet is smol: To earn the label, a cat or dog (or kitten or puppy) must excel in both the tiny and cute departments. A pet that’s truly smol is likely to induce excited squees from everyone around it.


Hands holding a puppy.

Like doggo, pupper is self-explanatory: It can be used in place of the word puppy, but if you want to use it to describe a fully-grown doggo who’s particularly smol and cute, you can probably get away with it.

10. BOOF

We’ve already established that doggos go bork, but that’s not the only sound they make. A low, deep bark—perhaps from a dog that can’t decide if it wants to expend its energy on a full bark—is best described as a boof. Consider a boof a warning bark before the real thing.


Dog noses poking out beneath blanket.

Snoot was already a dictionary-official synonym for nose by the time dog meme culture took the internet by storm. But while snoot is rarely used to describe human faces today, it’s quickly becoming the preferred term for pet snouts. There’s even a wholesome viral challenge dedicated to dogs poking their snoots through their owners' hands.

12. BOOP

Have you ever seen a dog snoot so cute you just had to reach out and tap it? And when you did, was your action accompanied by an involuntary “boop” sound? This urge is so universal that boop is now its own verb. Humans aren’t the only ones who can boop: Search the word on YouTube and treat yourself to hours of dogs, cats, and other animals exchanging the love tap.


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