Squirrels use sophisticated technique to separate nuts by type, study finds

BERKELEY, Calif. — Some squirrels go a little nuts when it comes to sorting their acorns, a new study finds. Researchers at UC Berkeley observed the behavior of 45 nearby fox squirrels over a two-year period, finding that they use what’s known as a “chunking” behavior — organizing items into various smaller subsets in order to better manage the overall collection — to categorize their various nuts. 

This is notable because humans also use chunking techniques, although generally for storing information, whether the data is of a spatial, linguistic, or mathematical variety. Taking your email, for example, and dividing the messages into various folders could be considered a form of chunking.

Fox squirrels use this strategy to divide the nuts they gather over a year — between 3,000 and 10,000 — into what the researchers term “subfolders,” one for each type of nut.

“This is the first demonstration of chunking in a scatter-hoarding animal, and also suggests that squirrels use flexible strategies to store food depending on how they acquire food,” says lead author Mikel Delgado in a university news release.

The researchers believe that this idiosyncratic behavior allows squirrels to both remember where specific morsels are, and to hide other treats from animals that could steal them.

“Squirrels may use chunking the same way you put away your groceries. You might put fruit on one shelf and vegetables on another. Then, when you’re looking for an onion, you only have to look in one place, not every shelf in the kitchen,” adds Lucia Jacobs, the study’s senior author.

YouTube video

These findings were discovered through the study’s principal experiment in which the squirrels examined were subjected to a variety of conditions relating to the locations and types of nuts provided. The authors provided the squirrels with almonds, pecans, hazelnuts and walnuts and monitored via GPS tracking where on the university’s campus the critters would bury their bounty during the two-year experiment.

To determine whether the way they were being fed mattered in the experiment, the authors gave some squirrels their nuts in organized rows of fours, while others were given them in a random order. Some were fed the nuts at the site where they last buried a nut, and some were fed at a fixed location.

The rodents, regardless of where they encountered or kept their nuts, were prone to separating them, even if they did so unconsciously.

“These observations suggest that when lacking the cognitive anchor of a central food source, fox squirrels utilize a different and perhaps simpler heuristic (problem-solving approach) to simply avoid the areas where they had previously cached,” the researchers conclude.

The full study was published last month in the journal Royal Society Open Science.

Comments

  1. John Muir’s favorite animal was the Douglas Tree Squirrel. H.D. Thoreau loved watching the tree squirrels as well.

  2. Road kill is comprised of many clueless squirrels, but comparatively few humans.

    My herb garden, free of any nuts whatsoever — squirrels neither bury nor unearth any — is savaged by imbecilic squirrels who are either wasting their time or simply amusing themselves by vandalizing a crop.

    Conclusion: Squirrels are less intelligent even than UC Berkeley researchers.

  3. Okay, I grew up in the country. We made squirrel gravy. True and it was pretty good on pheasant with mashed potatoes.

  4. Squirrels are a gift from God to the world to plant trees to filter the air & rain, and all they want to do is raise a family and plant trees. Never ever run over a squirrel.

  5. A few years ago squirrels planted black walnuts for me, and did almost too good a job. We had a lots of walnuts on the ground in the front yard. I hauled a few wheelbarrows out to the back of our small acreage, where there were no walnut trees, so the squirrels could plant them for me. I knew they would lose a few, but it seems like they lost track of most of them, because now I’m having to grub out the far too many walnut trees growing out back. (They don’t die easily.)

    AFAIK it wasn’t done by fox squirrels like those in the study. Maybe cnn or npr squirrels.

    I enjoyed reading about this study, but am not used to this concept of squirrels keeping their nuts in groups. I would like to know more.

  6. YEAH, DEMOCRATS ON ONE PILE, LIBERALS ON THE OTHER PILE, RINOS ON A THIRD PILE, SNOWFLAKES ON THE FOURTH, AD INFINITUM!

  7. I will share this knowledge … a squirrel will drop it’s nuts chucking for the golden treasure of a “Cheese It ” cracker.

  8. Is anyone else sick of watching tax dollars go to Lefty and Commie-infested public schools where they conduct “research” like this? These same schools sponsor outrageous anti-Western garbage as well that produces students and faculty that hate the civilization that made them possible.

  9. The Moral of the story … Squirrels know the difference in nuts & Numb Nuts do studies on why squirrels are smarter than them.

  10. Not that it isn’t interesting to learn things about animal behavior and abilities, but it must be great to have a career that pays you to study nearby squirrels.

  11. My dog just murdered a squirrel the other day. I protected him from the authorities by disposing of him in the Monday trash pickup.

  12. It’s a little unfair to tie these researchers with the antifa nitwits and a$$wipes, Berkeley hosts two ROTC units and site of the former Manhattan Project. A quick google will show their contribution to science and technology for this country can not be overstated.

  13. Squirrels in my area use a highly sophisticated binary mathematical system for grading and storing their nuts. A 1 means take it. A 0 means leave it. It’s uncanny! After a five year study I’ve discovered squirrels use a binary system just like early human software coders.

  14. A sample size of 45 is nowhere close to being statistically significant. They need samples from all over, thousands of them, in order to determine whether the phenomenon is localized, unique, or universal.

  15. THE SQUIRRELS ARE CHECKING TO SEE IF THE NUT IS ANY GOOD OR NOT. A HEAVY NUT MEANS NO WORM OR BUG HAS EATEN THE NUT. SQUIRRELS ALSO LAY OUT NUTS IN A GRID PATTERN. THEY DO THIS BASED UPON HILLSIDES, FLAT LAND AND WATER. SQUIRRELS ARE RESPONSIBLE FOR NEW TREE CREATION. SO THEY PUT THE RIGHT NUT, IN THE BEST SPOT, TO GROW THE RIGHT TREE, FOR THAT AREA! NOT ALL NUTS ARE PART OF THEIR WINTER HOARDS. ALL THEY HAD TO DO WAS ASK A SQUIRREL HUNTER! THEY ALSO MOVE FROM HOLLOW TO HOLLOW TO CUT NUTS. SOME TREE’S THEY DO NOT CUT THE NUTS. THE GRAY SQUIRRELS ARRIVE FIRST, USUALLY ABOUT 20″ TILL SUNRISE. FOX SQUIRRELS ARRIVE LATER. THE GRAY SQUIRRELS ARE ENERGETIC AND BARK A LOT. FOX SQUIRRELS ARE MORE SHY AND LIKE TO LAY ON LIMBS AND CUT. FOX SQUIRRELS SELDOM BARK. GREY SQUIRRELS ARE AGGRESSIVE. THEY ALSO RUN OFF FOX SQUIRRELS. THEY GO INTO THE NESTS OF FOX SQUIRRELS AND BITE OFF THE TESTICLES OF YOUNG FOX SQUIRRELS. WHEN THEY CUT, THE GREY SQUIRRELS CUTTING SOUNDS LIKE RAIN FALLING. WHEN A FOX SQUIRREL CUTS, HE CUTS QUIETER AND SLOWER, THAN DOES A GREY SQUIRREL.

  16. My bear cub is looking at colleges now and I told him he cannot even consider CA based schools.
    They are too crazy, too whacked out for an intelligent, logical, common sensical East Coast bear.

  17. As a resident of California we separate our nuts when we elect Democrats into office. Governor Brown is a walnut. He drives me up the wall. Pelosi is a coconut… she’s coo coo. Maxine Waters is a pea brain peanut.

  18. Squirrels Use Sophisticated Technique To Separate Nuts By Type, Study Finds. You mean they actually taste them first? That’s deep.

  19. This is a critically important finding. We now know that we have to elect squirrels to govern us in order to make sure our nuts get saved…

  20. I do lots of chunking with women. Those with great tits, ass, shape, I grade them and put them in different folders.

  21. They didn’t need a study to make these conclusions. I live on a protected oak sanctuary, and I have two huge birdfeeders.

    I spend a fair bit on the best bird food you can buy, it consists of walnuts, pistachios, peanuts and smaller seeds like barley, thistle and others.

    My property has the fattest birds and squirrels imaginable, I often see the squirrels use one hole for peanuts, some stash walnuts in other holes or in exposed knots in trees (We have four types of woodpeckers) and all of them raid the squirrels stashes if they try to store them in trees.

    One time I noticed a mound on my front lawn, inside was a cache of only peanuts, so I watched the feeders and noticed this odd behavior of chunking.. My wallet also often gets chunked, high quality bird food isn’t cheap.

    1. Maybe the squirrel’s are smart enough to know if they plant the peanut nuts and seeds they will sprout the next year and produce (grow) more seeds/peanuts. I also have a bird feeder and feed both birds and squirrels and watch them burry nuts and seeds. I have come to the conclusion that sometimes the squirrels forget where they burry seed and nuts and I have them sprouting up all over my yard and in my garden. This is probably how lots of trees and plants get started in the forest.

Leave a Reply

Your email address will not be published. Required fields are marked *