New Flying Squirrel Species Discovered along North America’s Pacific Coast

Humboldt flying squirrel.

Humboldt flying squirrel. [Photo by Nick Kerhoulas]

Press release from Humboldt State University:

Scientists always assumed it was a northern flying squirrel gliding through the canopies of Pacific coastal forests. 
But now a recent in-depth investigation of the animal’s DNA is proving otherwise. The furry critter is actually a distinct species, which has been named Humboldt’s flying squirrel, and a new study describes how scientists are up-ending flying squirrel taxonomy.
“For over 200 years scientists have thought that only two species of flying squirrels live in the Americas,” says Brian Arbogast, a University of North Carolina at Wilmington professor who directed the study “Genetic Data Reveal a Cryptic Species of New World flying squirrel: Glaucomys oregonensis,” published in the Journal of Mammalogy. Arbogast was formerly a professor at Humboldt State University’s Department of Biological Sciences and head of the University’s Vertebrate Museum.
How could a distinct species exist along the Pacific coast and escape the notice of scientists who first observed the northern flying squirrel in 1801?
“They look similar, but Humboldt’s flying squirrels are generally smaller and darker. With new genetic information we know that there’s no gene flow between the two,” says Nick Kerhoulas, HSU Biology instructor and a member of the research team.
Humboldt’s flying squirrel is what scientists refer to as a “cryptic” species, one that was not earlier recognized as being distinct based on its physical appearance. “If it had been something as obvious as a bushier tail, or distinct markings, scientists would have identified that already,” says Kerhoulas.
The research team analyzed the DNA of northern flying squirrels from across North America, with an emphasis on the Pacific Coastal region of the continent. Researchers combined information from mitochondrial DNA sequences and information from a different type of DNA marker, known as microsatellites, which are short repetitive stretches of DNA typically found in the nuclear genome that can help scientists identify levels of gene flow among populations. 
The results of the microsatellite analyses were striking. They indicated that no gene flow was occurring between the Pacific Coastal form and the widespread continental form of the northern flying squirrel. In other words, the Pacific Coastal flying squirrels were not simply a type of northern flying squirrel but were instead a separate, distinct species.
The new species is Glaucomys oregonensis, but the researchers gave it the common name “Humboldt’s flying squirrel” in honor of German explores and geographer Alexander Von Humboldt, and in a nod to the Northern California county that bears his name, says Arbogast. 
Western scientists have studied flying squirrels in North America for well over 250 years. In 1758, Carolus Linnaeus, father of taxonomy—the formal system of assigning every species a unique, two-part Latin scientific name—bestowed the scientific name Mus volans, which translates to flying mouse, on what is known today as the southern flying squirrel. 
The Latin name was later modified to Glaucomys volans, which has remained the same ever since. This species lives across much of eastern North America, primarily in deciduous forests. The range of this species extends further southward into the oak and pine forests in mountainous regions of Mexico and Central America.
Another species, the northern flying squirrel, Glaucomys sabrinus, was formally described in 1801 and is generally larger than Glaucomys volans. The northern flying squirrel has an expansive range across the vast coniferous forests that cover much of Alaska and Canada, from where it extends southward in similar habitats through the major western mountain ranges of North America: the Rockies, the Cascades, the Sierra Nevada, and also the highest peaks of the Appalachian Mountains in the east. 
New World flying squirrels, which now include Humboldt’s flying squirrel, are small, nocturnally active, gliding squirrels that inhabit woodland areas. The nocturnal habits of these animals mean humans rarely see them. 
The creatures don’t actually fly like bats or birds. Rather they glide from tree to tree by extending furred membranes of skin that stretch from forearm wrist to ankle on the hind leg. Their feather-like tail provides extra lift and also aids in steering. 
They are capable of gliding for up to 100 meters and can make sharp, mid-air turns by using their tail as a rudder and moving their limbs to manipulate the shape and tautness of their gliding membranes. 
These aerial feats are even more remarkable given that flying squirrels often have to navigate through dense forest in the darkness of night. Their large eyes give them excellent vision, but the mechanisms of their navigation and judgment of distances while gliding remain largely a mystery.
Full text of the study is available online.


  • Very cool!

  • Way cool

  • Oh my God that is so cool.

  • Crazy I lived here my whole life and never saw a flying squirrel

  • Seen them. Hear them at night. The hills east of Piercy still boast Spotted Owls, Salamanders in abundance, flying squirrels, and one Fischer sighting. That is … good until the greenrush newbies start trashing the joint.

    • I seen one about 15 years ago in the Redwoods near Dyerville Loop swimming spot. Just North of Weott. Pretty awesome!

  • Mr guest I to have lived in Humboldt my whole life ,and i just found out about them, so cool nature always finds away.I just think the fact we have flying squirrels is fantastic. Thank you kym, for infighting your readers.

  • How exciting!

  • Now we just need talking Moose and we’ll be set.

  • What guest said…neat.

  • Fascinating for a fact!!!

  • Where’s Lady Bird Johnson when you need another ban, one on logging in the area where these little critters need to fly from tree to tree?

  • Honeydew Bridge C.H.U.M.P.

    Need to make sure weed isn’t being grown within 50 miles of their habitat.

    The dope growers closed the mills, how ironic if they get a massive dose of their own medicine…

    Pretty sure dope growing disrupts their life cycle, so let’s save the flying squirrel by shutting down all marijuana growing.

    You hippies have so earned this, can’t wait.

    • Please stop ruining every post with your verbal diarrhea. Please. Just give it a rest.

    • Oh it all becomes clear now. You think these third generation farmers have one scintilla of connection to the environmentalists who called out the rapacious logging practices you are guilty of!! You were wrong to do that. And your powers of observation and judgement have not improved with time.

    • The growers closed the mills? That’s a new one.

  • I would see them nearly every morning at dawn when I was falling old growth Redwoods in the 70’s and 80’s.

    • Yes saw them fairly often while working in the woods near Klamath around that time….Very interesting animals !

  • I told everyone about seeing these squirrels as a child and no one believed me. In your face!!!

  • Saw them frequently in Willow Creek most often in day-time. What is the range of the Humboldt’s?

  • Triniboldticino

    They’re pretty much nocturnal. HUGE black eyes. Even in ranges with other subspecies, it is often difficult to observe them. Unless they’ve been living in the cabin and you open it up for the first time of the year and the Malemute gets through the door ahead of you and spots one in the middle of the floor. Then the ensuing Roadrunner/Coyote cartoon, with both animals running at 80 miles an hour and neither of them going anywhere or getting traction on the wood floor you painted last fall on the way out the door. Boy, warnt’ the dawg frosty for the rest of that weekend. Guard hairs standing straight out, ‘ol Breeze.


  • Another animal, seldom seen in northern Cal. That I thought was a myth, in these parts anyway. Is a Ring Tailed cat, (not a cat at all ) That is until I saw one crossing the road near Zenia early in the morning, before light, while driving to go deer hunting, 20+ years ago . The white rings on the tail were much whiter than a raccoon. it’s front half was smaller than it’s back half. it loped across the road rather than scurrying like a raccoon. I always wished I could have taken a picture of it.
    Has anyone else seen one? The Flying squirrel is truly cool. May it leap through the forests for many years to come.

    • Yes, saw one crossing the road on the way home from a Grange meeting on Wilder Ridge probably 30 years ago. Then more recently my old renters saw one in a tree near their ducks. An old neighbor who passed away said she had one as a pet when she lived near the Eel River south of Benbow as a child.

    • I first saw a ring-tailed cat in 1972. Noise in my pigeon coop, middle of the night, I went out and saw one bird headed down a hole in the middle of the dirt floor, about 5″ in diameter. The bird was already dead, so I pulled it back (decapitating it) and put the body a foot away. About 2 minutes later, the cat appeared out of the hole and recovered its kill.
      The next morning I found the other end of the tunnel under some brush, easily 15 FEET away from the loft. (I covered the dirt floor with a scrap of chain-link fence. No more problem.)

    • A ring tail cat used to visit me all the time out in the willow creek area. He would climb the side of the cabin and look in the sliding glass door.

      • Flying Squirrel- still waiting to see one.

        Ring Tail Cat- I was clearing a blackberry thicket from around a friend’s chicken yard, about ten years ago. As I rolled back the growing bale of canes, I uncovered a BIG ground squirrel hole — or so I thought. A few minutes later the ring tail popped up from another hole next to the coop, jumped up on the roof and gave me the most piercing quizzical look. After staring at me for a long feeling time it gently shook its head, seemed to shrug its shoulders and then leaped into a thicket on the other side of the chicken yard. I sensed rather than heard it move away.
        My friend said he thought he had been providing a lot of feed for very few eggs. Neither he nor I thought the improvement in egg production was worth the loss of the ring tailed cat from the neighborhood.

  • Are they good too eat?

  • We had flying squirrels in covelo when I was a kid. After I shot them they would fly right out of the tree

  • One of these little guys regularly shows up at night to eat from my bird feeder. I leave him apples and pistachios to eat. It is very cute and quite brave.

  • I told people I saw those,and ya right your so nuts,so I like the in your face comment. So too all those friends and family that called me nuts IN YOUR FACE AS WELL!! LOL🐿

  • Yup River Rat, the ringtails are alive and well out here in Hetten. We’ve had a family living in our barn going on 10 years. Not a problem like the coons. They stay out of the way unless it’s a drawer that they want to nest in. That’s a whole nother can o worms you just don’t want to open. lol

  • mendocino mamma

    Saw a large ring tail cat in Potter Valley 2 weeks ago loping across a vineyard. Thought that is NOT a housecat…nor a bobcat. Found scat all over on trail. Then a couple of mornings later pile of mocking bird feathers next to the trail I saw it loping on prior. Pretty dang cool.

  • Wow, thanks for posting this Kym! Different species but I held flying squirrels as a kid on the east coast. Our friends caught them in their bedroom, and let them go later. Very soft and sweet- they didn’t bite. Very fragile tiny things and so cute.

    Glad to hear in the comments that the ringtails are still here and seem to be doing well 🙂 That’s a lot of sightings for such a shy animal.

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