Friday, December 10, 2021

Woolly Bear’s Mountain Winter Forecast

woolly bear Its that time of year again!!  The temperature has dropped and snow blankets the Adirondacks.  For most of us here, Winter can seem to last forever and any foresight we can get of what to expect, can be welcomed.  Like many other creatures, the woolly bear is now nestled into their Winter hideaway and will hibernate until Spring.

As a Lepidopterist, I have had the privilege of interacting with these caterpillars in an up close and personal manner.  These creatures are thought of by many as being simple and insignificant but I assure you they are anything but.  The life of a woolly bear is long, arduous and miraculous.  From ground dweller to free flight, the life of this larva is one of the greatest sights to witness throughout the insect world.  We have had folks bring us a variety of insects in all stages of life in attempt to preserve their lives.  In the past, we were brought woolly bear eggs from a couple who trimmed a tree not realizing eggs were laid on a leaf of one of the branches.  We had an idea of what creature would hatch from these eggs and two days later 14 tiny black woolly bear caterpillars appeared.  These caterpillars, the larva stage of the Isabella tiger moth, are hardy eaters and grow very quickly.  Their orange band appears by the second instar and remains throughout the larval stage.  After handling these creatures regularly, they ceased to roll into a ball – a defense mechanism when they are afraid and instead remained fully opened as if they were aware I was not a threat.  When speaking to them, they would raise off their front legs toward my voice in acknowledgement something was there.  As Autumn arrived, these little cuties were released back to the wild in order to bulk up for the coming Winter and seek out their cold weather getaway.

woolly bear winter prediction

It is known that the woolly bear’s ability to forecast the coming Winter is folklore, but what an amazing way to bring attention to this fuzzy and interesting creature.  The folklore suggests the wider this caterpillar’s brown ring, the milder the upcoming winter will be.  If the woolly bear is mostly black, it means a harsher winter. If mostly brown, it means a milder winter. If brown at the head with more black near the tail, it means a winter that starts mild and ends harshly (and vice versa).  The woolly bear may not be able to tell the future, but they may be able to tell us about the weather in the past.

The coloration and the length of the bands do have a correlation to how long there was warm weather until cold weather set in.  The warmer and longer the growing season they have, the wider that round rust-colored band becomes in the middle.

Each time it sheds its coat, it becomes a deeper orange.  Their furry coats protect them from freezing, down to -90 F so surely, they are equipped for Winter in the Adirondacks.

Check out my picture of a woolly bear taken this year in Wilmington at the top of this post.  Follow the guide above to find out what this little guy predicts for the mountains this year.  Let me know what you think he’s saying!!

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Jackie Woodcock was born and lives in the Adirondack Mountains. She is an apiarist, lepidopterist, conservationist, teacher, writer, artist, and a co-owner of SkyLyfeADK. You can find her SkyLyfeADK on Instagram and Facebook.




13 Responses

  1. Richard Monroe Richard Monroe says:

    I loved this article! I’ve always relied on woolly bears to predict what the upcoming winter will be like.

  2. Jackie,
    It’s nice to have a timely story about woolly bears, and you’re right that woolly bears are just as accurate as humans in forecasting the future weather – which is to say, not at all accurate. In contrast, their size and color pattern can indicate something about past weather conditions, as you noted. But their furry coats do not protect them from freezing temperatures; that is a result largely of “insect antifreeze” – increasing solutes, especially glycerol, in their hemolymph. A good reference is: Layne et al., 1999, Am. Midl. Nat. 141:293, “Cold hardiness of the woolly bear caterpillar (Pyrrharctia isabella).”
    Good luck with your observations.

  3. Ethan says:

    Beautiful photo and lovely educational story. Shared. Thanks, Jackie!

  4. Patrick says:

    According to this picture , and if the upper part is the front (according to article it raises its front legs when you talk to “him” ) it will be a mild winter, especially in the beginning. There are at least five bands of brown (red).

  5. Beth Rowland says:

    Wonderful ;piece—thanks!

  6. JB says:

    I love folklore. I wonder how far back this one goes (Native Americans had similar weather forecasting stories). Thanks for sharing this year’s “forecast” with us. So far, it has indeed been unusually warm.

  7. Nora says:

    Beautiful and interesting article, fasanating creatures. Thank you Jackie!!!

  8. Boreas says:

    In my experience, the first thing out of their mouth is “Please don’t eat me!”. Most predators don’t need to be told.

  9. Linda Brown says:

    What about mostly brown and black on one end only.

  10. Jennifer says:

    I’ve seen several here in Janesville, Wi that are completely black. I’ve never ever seen that before.

  11. Charlie Stehlin says:

    “So far, it has indeed been unusually warm.”

    And getting warmer every year! We’re breaking record highs every year. At this rate we won’t need frying pans to cook our eggs, or burgers…..we can just place them out in the open summer air. We can save on gas, or electric.

  12. Charlie Stehlin says:

    “These creatures are thought of by many as being simple and insignificant but I assure you they are anything but.”

    The same goes for all critters Jackie….I assure you!

  13. Charlie Stehlin says:

    “When speaking to them, they would raise off their front legs toward my voice in acknowledgement something was there.”

    Interesting but not surprising. Was it maybe they acknowledged a presence because you were close and the warmth of your breath flowed over them? One thing is for sure….there’s a reason why wooly bear’s are here, they serve a purpose, and it is good to know at least some people are paying them some mind.

    “After handling these creatures regularly, they ceased to roll into a ball ”

    I remember years ago, decades, I was in a woods and came upon a tree frog vertically attached to the trunk of a tree at eye level. I began gently nudging it with a fingertip and the critter stayed put, did not even hint of taking a leap and hopping off to evade big human me. I felt strongly at that time, that that frog sensed no danger from me….is why it stayed put. The critters and creatures generally know what or whom poses a threat to them, a built in survival nature which all creatures have. Even a worm knows danger as it stretches out or shrivels up to avoid the incursion of a blade.

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