” I found a weather caterpillar!” a young student called out during a field trip to Crossroads at Big Creek. I knew that my lesson plan was toast. I can’t compete with a woolly bear.
A woolly bear…Almost all kids recognize the brown and orange larval form of the Isabella tiger moth. They know that if you hold them or just touch woolly bear caterpillars, they roll into furry little balls. And most kids are familiar with the superstition that these banded creatures–rusty-colored in the middle and black on either end—predict weather. This is not just a local legend. Apparently, all over the country, people of all ages believe that the width of the central band will predict the severity of winter.
Sorry, but no. Scientists, zookeepers and students have spent years studying woolly bears and they have discovered absolutely no correlation between the width of the brick-orange band and the severity or length of winter, though some suspect that the width of the band might possibly reflect the temperature and moisture conditions of the previous summer.
The kids who visit Crossroads would just love to catch these distinctive caterpillars, take them home and put them in a jar and watch them spin a cocoon. That is just not going to happen. Wooly bears do not spin cocoon until spring. So what were they thinking coming out in the November?
Truth is, wooly bears don’t do much thinking. If it is warm outside, they eat. If it is cool, they rest.
If it is really cold, they they crawl under piles of leaves or logs and hibernate…which means they slow down so much that they are almost…but not quite dead. Last week, when we found them crawling around Crossroads, it was quite warm, so probably, the caterpillars had come out to eat.
A couple years ago, we experienced a January thaw. It got so warm that the caterpillars woke up from hibernation and started crawl around looking for food. In many places, the snow melted and lawns were green, and those hungry caterpillars may have been able to munch for a couple of days.
Did they spin their cocoon in midwinter? Probably not. They have to feed for two or three weeks before they spinning their cocoons out of silk mixed with their bristly caterpillar hairs. I would be very surprised if they were able to eat enough during a January thaw to get them ready to become a moth.
Tender-hearted children (and adults) often worried about woolly bears being out in the cold. Kids want to be kind and bring the insects inside where they will be warm. That is the absolute wrong thing to do. In winter, woolly bears are supposed to be cold and they are supposed to go without eating. If you warm them up and feed them, they die before spring and never become moths.
So what should you do if you find a woolly bear on a warm day? Enjoy looking, and let the little guy crawl. He’ll crawl until he finds a nice cozy spot, just like he did in October. And then, he’ll curl up and wait for true spring, just like the rest of us.
On warm November days, woolly bears can be seeing crawling at all three of Crossroads properties. The Big Creek Preserve (parking at 2041 Michigan), The Cove Preserve (grass parking area at the intersection of Utah Street and 20th Place, and the Ida Bay Preserve (parking at the intersection of Canal Road and Buffalo Ridge Trail) are all open and free to the public.
We hope you enjoy the wooly bears, but to learn about weather, check the Crossroads website www.crossroadsatbig creek.org or the Door Peninsula Astronomical Society site www.doorastronomy.org ( for current conditions at the Leif Everson Observatory.) For predictions, check the NOAA ( National Oceanic and Atmospheric Administration) site to learn about jet streams and possible Polar Vortex conditions, or one of the many prediction sites They are far more accurate than wooly bears, but they aren’t always right either.
Crossroads is a community supported learning preserve made up of three properties. The Collins Learning Center (located at 2041 Michigan) will be open form 2:00-4:00 this week. No public activities are scheduled for this week.
