Clellie Lynch: To migrate or to hibernate?

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No morn — no noon!...

No shade, no shine, no butterflies, no bees,

No fruits, no flowers, no leaves, no birds —

November!"

"No!"

— Thomas Hood

EAST CHATHAM, N.Y. — As this unseasonably warm October comes to a close, the warmest in recorded weather history, November breezes in on a blanket of cold arctic air, frosting lawn, leaves and edges of ponds. Trees are bare now, branches reaching towards the sky, spiky and gray. Though the grass is still green, strewn here and there with rusty leaf carpets dotted with shriveling gold and red bits, the last of the colorful flowers — nasturtiums and marigolds — wave good-bye for now. A hard frost has come so very, very late!

As we do, the natural world too must prepare for winter. Trees, shrubs, flowers and weeds toss away leaves and seeds and go dormant for the ensuing cold months. Some animals, however, must either find a source of food or sleep away these dreary months. Migrate or hibernate, that is often the question.

Migration is easier for birds who may wing their way south where there is a food supply, especially living, flying, crawling insects. Juncoes and white-throated sparrows (seed eaters) arrive, down from their hilly summer residences. Skeins of honking geese, often heard and not seen, fly south. Robins and bluebirds flock (not together, thank you very much), forming protective phalanxes for the oncoming winter. The morning chorus is meek, sounding like a couple of musicians tuning up before a performance. Migration is trickling to a close. Our winter birds are settling in.

Insects too are folding their wings: laying eggs before dying, heading south or finding suitable cracks and crevices in logs or dirt — or houses — to sleep the winter away. Now and again while I am out walking, a ladybug crashes and lands on me, perhaps disorientated by the sudden onset of cold or maybe wanting to hitchhike into the house to hibernate.

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Curiously, the last few woolly bears I've seen are large and have only black about the head, the brownish part extending all the way to its rear. Maybe this is predictor not just of a warm winter, but of major climate change. Someone should inform that man in the White House. He's more likely to believe a caterpillar than a scientist.

The stalwart peeper, constantly trilling and trilling near the pond this warm autumn, is silent now, joining his amphibian and reptilian relatives hunkering down in the mud. No frog eyes or turtle heads appear poking through the surface of the water scanning for bug or beetle lunches. Occasionally though a dragonfly, hungry and oblivious to the change in weather, circles above the pond looking for the same said insect meal.

DO RODENTS REMEMBER?

In preparing for winter, mammals either hibernate (bears) or have evolved to withstand the cold and to find food throughout the winter (deer, coyote). At the moment squirrels and chipmunks are frantically gathering seeds, especially acorns that litter the lawns and carpet the roads. These furry rodents stash them in various places. Whether they remember where is debatable — they're not admitting to anything. It might not matter since the woods will be filled with so many nut caches the squirrels will just have to stumble around trees and down branches poking a paw here and there to come up with a handful.

Hibernation, also called winter sleep or dormancy in winter, occurs when the body metabolism drops and the heart rate slows, enabling the creature a continued sleep with no need to feed. Many animals fall into a true hibernation, but many more lapse into a temporary hibernation or torpor, sleeping and occasionally waking to move about and grab a snack before closing their eyes again for another long rest.

In looking in the OED, I find the word, "hibernate" did not enter the lexicon until the 17th century, referring to plants, citing Evelyn in 1664 about "moving plants into the green-house to hybernate" and the 19th century for animals, citing an 1802 use by Erasmus Darwin, Charles' grandfather, about mammals. Places for hibernation were once called hibernacles. Now that term refers only to snakes, particularly garter snakes, that den up with many, many others to persevere through the winter.

When we think of hibernation, we think of bears, fat sleeping bears and deep dark dens in the woods. But many creatures hibernate during these cold, gloomy months when food is not plentiful or maybe in really harsh winters, non-existent. In the 19th century, Samuel Scoville, Jr., alluding to an ancient legend about the seven youthful sleepers of Ephesus, wrote "The Seven Sleepers" — bat and bear, jumping mouse and chipmunk, woodchuck, skunk and raccoon — a poem to teach children about hibernation.

Bats are true hibernators, spending 3 or 4 months asleep, living off autumnal accumulated body fat. The heart rate drops from 400 bpm to 25. Bears too are true hibernators, their body temperature dropping a few degrees, but their metabolisms slowing down by 75 percent. Woodchucks, too, fall into that long sleep, taking a breath once every six minutes dreaming of gardens to maraud. Mice take to houses or find a place in woods or barns to sleep away the winter. Skunks and raccoon are torpor hibernators waking now and again for a crawl/creep about. Maybe this occurs during a January thaw.

Hibernation in amphibians varies greatly: some actually freeze where they are denned. Others store up glucose which acts as an antifreeze. In the literature, newts are said to float around under the ice, once in a while taking to the mud for a few days of complete dormancy. Toads, on the other hand, cover their bodies with mucus which prevents them from freezing. Insect species like some reptiles and amphibians that attempt to survive the winter, produce glycerol which also is an antifreeze.

We need not think of November like many a poet in terms of gloom and doom, the drear and dour, the solemn and somber. Nature is just taking a long sleep. You too may fashion your own home hibernacle and retreat into the warmth with a pile of books, a selection of movies and a hot toddy to wile the winter away!

Clellie Lynch is a regular Eagle contributor.


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