A naked, living critter fully exposed to below-zero temperatures for 24 hours – with a pleasant, stiff breeze tossed in for good measure – should by most reckoning be dead. We know there’s science behind surviving such conditions, and that some creatures manufacture their own anti-freeze, which lowers the freezing point of their body fluids and allows them to survive. Still, seeing it happen firsthand is sort of like watching a good magician: the eyes and mind are saying, “I see it, but I don’t believe it,” even though we know there’s a rational explanation behind it all.
The recent mild weather, interrupted by a cold snap, brought the concept to life at our home south of Plattsburgh. With the temperature at 71 degrees on Christmas Eve, ladybugs were popping up here and there inside, and a flying wasp hovered overhead as I exited the front door. (For further and humorous evidence of the warmth, take 40 seconds to check this out from a smart, talented, and funny artist/writer/musician friend of mine).
On Monday, January 4, our temps plummeted, ranging between zero and 15 above. That morning I saw a presumably dead wasp on our front sidewalk, but a light touch from my finger caused it to pull away slightly, apparently unable to react vigorously due to the cold. Still, it was clearly alive.
After retrieving our mail, I decided I couldn’t just let the wasp die, so I moved it into some leafy debris, despite my assumption that virtually nothing could escape the penetrating cold. I later found another wasp on the sidewalk, but left it there just to see what would happen.
The next morning at 8:30, our temperature was 8 degrees below zero. The wasp was still on the sidewalk, but was upside down, suggesting it had succumbed. Lying flat on its back, with legs curled inward, it sure looked dead to me. I rolled it over twice and regretted having left it to die, but a couple of hours later when I stooped to give it a light touch, there was slight movement. The temperature was still below zero, but the sunlight by this time was reaching that portion of the sidewalk.
It remained a very cold day, barely rising above 10 degrees, but the wasp eventually became mobile enough to walk (very, very slowly) about 18 inches to where the sidewalk met the house. It stayed alive through overnight temps of around zero, and remained inactive for most of the morning. Later on Wednesday, when we reached a balmy 26 degrees, it was no longer there, presumably having become mobile enough to find shelter in the wall or further inside the house or garage. Was this normal?
Several online searches revealed that only the queens of certain wasp families survive the winter, and like other creatures, they are sometimes fooled by unusual warm spells that suggest spring has arrived. Maybe that’s why our wasps had emerged, but it still seems shocking that they didn’t die from lengthy, open exposure to such brutal cold. I did find online at least one other person with a similar experience, having picked up the body of an apparently frozen and dead wasp for further lab study, only to find it very much alive and active after having been warmed.
On one website, Michigan State University entomologist Howard Russell wrote, “Yellow jacket and paper wasp queens, some mosquitoes, and the mourning cloak butterfly also overwinter as adults. Like the ladybird beetle, they seek out sheltered spots and become dormant until warm weather reactivates them.… With or without antifreeze, most insects simply can not function at temperatures below 40 degrees F. Their body chemistry simply doesn’t work at low temperatures, so they can be active only when the world warms up around them. In areas where part of the year is cold, they’ve developed this wide range of techniques for surviving the cold and assuring the survival of their species.”
In NYS’s DEC publication, The Conservationist, it was noted in a 1976 issue that “paper wasp (Polistes) queens often successfully withstand Canadian temperatures of 27 degrees below freezing as they lie dormant on ledges or corners of buildings.”
Still, 40 degrees and even 5 degrees hardly compares with below-zero temperatures (even without the chill factor we experienced). A paper (from 2004) by Raymond B. Huey of the University of Washington includes this: “Do animals use any of these alternatives (“freeze avoidance strategies”)? [Answer]: Animals aren’t pure water, so their FP [Freezing Point] will be of course < 0°C. Moreover, many insects and some frogs accumulate glycerol in winter (30% of one wasp is glycerol!), thus lowering their freezing point.”
Watching a nature show depicting frozen wood frogs was fascinating—if dropped, they would shatter like glass, and yet revived with warmth—but it’s still pretty cool (sorry) to see similar survival capabilities of creatures right in our own front yard.
Photos: Our porch corner, and one of many paper wasp nests squeezed between eaves and gutter