Woolly bear caterpillar. Photo by Iron Chris, Wikimedia Commons
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There are many amazing things about living systems that are both observable and explainable. One aspect of nature, though, that probably isn’t really explainable, involves organisms like oak trees and woodpeckers and spiders forecasting, many months ahead of time, the intensity of a coming winter. For this to be observable and explainable one would have to assume that these species (and many more for that matter) somehow perceive clues in the environment that we lumbering (but sentient) bipedal primates do not.
Take the woolly bear caterpillar for example (pictured above): it is alleged that they take on a darker color if the coming winter is going to be more severe. What would be the trigger for that color change? And, maybe even more significantly, why would they do that? Even if they could perceive some clues that the coming winter was going to be cold and snowy, what advantage would it be to the caterpillar (or to the overwintering pupa of that caterpillar, actually) to have an abundance of black body hairs? There would have to be some selective advantage or the character would never have evolved!
Fifteen years ago I had an ecology student who wanted to study woolly bear caterpillars. His idea was to collect as many woolly bears as possible and see if their “message” was consistent across the population. He collected one hundred woolly bears over a four week period and measured the width of their color bands. He found that their winter forecast was, at best, random. The early collections seemed to lean toward a mild winter (narrower black bands and a broad orange band) and the later collections seemed to lean toward a more severe winter (broader black bands and a narrower orange band) but the variation in each collection almost completely obscured their overall trends.
We determined two things from this woolly bear study: 1. As woolly bear caterpillars age and grow, they develop more black hairs, and 2. Selective observation of the woolly bear population (only observing a very small number of individuals at any one time) could lead you to conclude whatever you might want about the coming winter.
Selective observation may be the operational idea here!
Photo by rhaij, Pixabay
There are a number of winter-predictive observations that involve things happening “earlier” than usual. There is the “early” departure of migrating geese and ducks, the “early” migration of the monarch butterflies, and the “early” hiving up of honey bees. The quality of these observations, of course, depends upon prior knowledge of exactly when these events have happened in the past and, therefore, should be happening in the present. This data is not readily accessible.
There are also a number of winter predictors that involve a usual activity of an animal but at a slightly more intense level. Migrating geese fly “higher” than normal, muskrats dig their winter burrows “higher” up on the river bank than normal, or crows gather into “larger than normal” winter flocks!
Photo by Jamaine Wikimedia Commons
There are also a number of observations of things being more abundant or more developed than average. An “excess” abundance of acorns, “thicker than usual” corn husks, “tougher than normal” apple skins, “more abundant than usual” late summer frogs, “thicker hair than usual” on the back of a cow’s neck, more mice (or crickets) than “usual” entering your house, more and larger cones “than usual” on pine trees, and “larger than usual” spider webs being spun out in the garden. Again, the data base of “normal” or “usual” for all of these events just does not, as far as I know, exist, but if you happen to see a large spider web, or happen to hear lots of mice in your kitchen, then you might easily jump to whatever conclusions you want and then feel the need to start stocking up on canned foods!
Squirrels are also frequently used as winter-indicators. They “frantically” gather acorns in anticipation of a coming hard winter. I have never seen a squirrel gathering acorns (or chestnuts, or hickory nuts) in anything other than a “frantic” manner. A leisurely working squirrel is very likely to become a quick lunch for a red-tailed hawk!
Raccoons with thick, brightly banded tails (another indication of a coming harsh winter) might just be getting their individual “blankets” ready for a long, cold winter torpor. Ants marching in a line might just be gleaners and gatherers moving as efficiently as possible to take food stuffs back to their nests in anticipation of a long winter to come! And, pigs gathering sticks … well, that is said to be a sign of a hard winter, but I didn’t even know that pigs ever gathered sticks, and I don’t know what they might be doing with those sticks (unless they are building stick houses against some big-bad-wolf!).
Snowy owl. Photo by P. K. Burian. Wikimedia Commons
There were a couple of nature’s “winter predictors” that might have some validity, though. The “early arrival of snowy owls” might be indicative of the early movement of cold, polar air masses down to lower latitudes. Frantic feeding activity by birds at our bird feeders might be the local avian fauna reacting to increasingly colder nights and the steady autumn build up to a long, hard winter. A “foggier than usual” August and a prevalence of autumnal halos around the moon might also indicate the early arrival of colder, northern air masses which could foreshadow a longer, more intense winter. I am not sure how a later first autumn frost or a summer that was unusually long and warm might explain a coming long, cold winter, but I am sure that they each sometimes go along with a gray, endless January and February!
Or not.
My favorite winter-intensity myth stated that when two woodpeckers share a tree hole the winter will be severe. I am not sure if it matters what kind of woodpeckers might be co-habitating, but I am keeping my eyes open for that one!
Enjoy the fall while it lasts, everyone!
It is typical of our species that we entertain such obviously illogical ideas as portents of the near future. It is also very unfortunate but typical that we ignore obvious signs of collapse in the natural world around us, even when those signs portend not just our possible winter wardrobes but our every existence.
I’m down on Key West for a few days, having flown a gaggle of drunken pro-trumpers here, burning 635 gallons of kerosene. Took a snorkel cruise to Rock Key, along one of the largest reef systems in the world. That reef is now mainly dead, victim of warming, acidification, and disease. Even though this island’s economy depends completely on reef tourism, the local paper described the paltry efforts being made to raise a scant million dollars to do something about it.
Over thirty years ago I dove on the Great Barrier Reef off northern Australia, so I know what a healthy coral reef looks like. I understand that reef is now also dead. In fact half of all the coral ecosystems on the planet have already succumbed with only a 1 degree C increase in temperature. As we keep pumping GH gases into the atmosphere, heating the sea and dissolving CO2 into it, 90% of corals are expected to die very soon.
Long story short, we see what we want to see.