Leave the Predictions to Weatherbug, Not Woolly Bears!

The wide reddish-brown band on this woolly bear caterpillar could raise false hopes of a mild winter.  All the wide brown band tells you is that this caterpillar is mature and well fed.  That's good preparation for this creature as it crosses a bike path to seek shelter for the winter.  The caterpillar can survive even frozen solid.  (Photo by Don Comis)

On my annual walk from Kenyon College to my home in Apple Valley, using the Koksosing Gap Trail for 4.5 miles of the approximately 8-mile walk, I saw my first all-black caterpillar—well, actually I saw two of them, along with a few woolly bear caterpillars.

I probably had seen black caterpillars before but thought they were woolly bear caterpillars predicting a totally bad winter.   But I've learned that the width of the middle reddish-brown band on the brown and black woolly bears being a predictor of the severity of the upcoming winter is a myth.  Ironically it was started by a scientist, but later disproved.  Now scientists know that the only thing more brown on a woolly bear means is that the woolly bear is older, or  better fed, or both.

 The caterpillars are born mostly black and the brown band grows wider as the caterpillar gets bigger, with age and diet.

Since I saw two of these all-black caterpillars on Nov. 10, I believe they  are the caterpillars of the giant leopard tiger moth,not woolly bears--which become Isabella moths next year.   (Photo by Don Comis)

I also learned that woolly bears become Isabella tiger moths in the spring.   I found that out when I sent a photo of a woolly bear to the “Butterflies and Moths of North America” website and added that moth to my list of 111 moth species in Knox County, mostly found in Apple Valley.

But, fortuitously, the day before my big walk on Monday, Nov.10, I read a column in the Sunday Columbus Dispatch by John Switzer, one of my two favorite Nature columnists in the Sunday paper. Switzer was describing his daily walks in the country in November and mentions not only the woolly bear-Isabella connection, but also the fact that the all-black caterpillars become giant leopard tiger moths.  He quotes my other favorite Columbus Dispatch columnist, Jim McCormac, as saying that this moth is quite attractive.  McCormac, whose blog convinced me to use “blogspot.com” for my blog, also told Switzer that almost all the furry caterpillars we see in the fall turn into one of the many species of tiger moths.

Switzer says that in addition to black and brown, the furry fall caterpillars also come in blond and reddish-blonde.   At Apple Valley, I've seen two different species that are white—the banded tussock or pale tiger moth and the hickory tussock or hickory tiger moth.  I managed to photograph both the caterpillar and moth stages of the hickory tiger moth.

Certainly if Switzer, a former weather columnist, had any hopes left of a mild winter after seeing a woolly bear with a wide brown band, it's gone as the second snow of the season is falling tonight, one that could bring 2 to 3 inches--and be followed by below zero nights!  The snow came earlier than usual this year, with Cleveland getting 8 to 10 inches recently.

But then what does a woolly bear care about weather when it can survive the winter frozen solid?

The funny thing is that the very first blog I wrote, on Nov. 6, 2013, was on the woolly bear’s inability to predict weather.  Up to recently it had remained in the top five most popular of my postings, until the weekly mastodon reports wiped it and all other topics out of the top five.

White is one of the many colors the furry tiger moth caterpillars come in, depending on the species.  This is the hickory tiger moth caterpillar.  (Photo by Don Comis)

Note:  I also have a website where I post information and photos on archaeology finds as well as all other aspects of natural history.  This blog and website began to catch the spillover from the monthly stories I write for the Apple Valley Cider Press, mainly a regular "Nature Article" feature.