#Biodiversity150 number 14 of 150 Arctic Woolly Bear Caterpillar

14/150: Woolly Bear Caterpillars Surviving Winter

Animalia: Arthropoda: Insecta: Lepidoptera: Lymantriidae: Gynaephora: Gynaephora groenlandica (Homeyer., 1874)

Tired of winter? Get some tips on winter survival from the Arctic Woolly Bear caterpillar (Gynaephora groenlandica). Did you know this caterpillar lives up to 7 (some suggest 14) years before pupating into a moth? It can be found in the Arctic Circle, in Canada and Greenland, and this furry crawler freezes solid each winter and can survive temperatures of -60C. This caterpillar spends most of its life frozen and only thaws for a short time each summer. With such a short feeding season it takes around seven years to accumulate enough food to pupate.

How does the wooly bear survive you might wonder? Well it has its woolly coat to help retain heat of course, but it also produces cryoprotectants within its body, mainly glycerol and sorbitol, to prevent tissue damage during freezing. The caterpillar also has some specific behaviours that help keep it warm; firstly they will bask in the sun to warm up and heat up their coat, and secondly they seek out overwintering sites usually within rocks and spin a light silk structure called a hibernaculum.

There are also two other species in Canada that are often referred to as “woolly bear” caterpillars. There is the Black Woolly Bear (Arctia caja) and the Banded Woolly Bear (Pyrrharctia isabella). The Banded Woolly Bear caterpillars are quite popular in North America folklore for being able to predict the severity of winter based on the width of its orange band. In fact, several places host Woolly Bear Festivals in the fall, complete with caterpillar races! Better add that to your bucket list #Canada150 #Biodiversity150


An Arctic Woolly Bear Caterpillar basking in the sun on Baffin Island, Canada. Photo Credit: Mike Beauregard goo.gl/fTMVa9
Specimen CNCLEP00028423 – Bylot Island, Nunavut, Canada – 25-Jul-2006 Photo Credit: Jean-Francois Landry, Canadian National Collection

Here’s the barcode sequence information for this species:

Process ID:  GRAFW688-12

nucleotide sequence


amino acid sequence


Visual representation of DNA barcode sequence for Arctic Woolly Bear Caterpillar


Learn more about it’s BIN (Barcode Index Number): BOLD:AAE6832

Title Image: Specimen ZA2011-634 – Zackenberg Research Station, Greenland – 20-Jun-2011
Photo Credit: CBG Photography Group, Centre for Biodiversity Genomics