A Northwoods Almanac for February 4 – 17, 2022 by John Bates
Groundhog (Woodchuck) Hibernation
I’ve written in the past how the idea of Groundhog Day always cracks me up, at least for Wisconsin’s Northwoods, given that groundhogs are deep in hibernation and are not in the least likely to poke their heads above ground to see if the sun’s shining. When a groundhog enters hibernation, its body temperature drops from around 99 degrees F to as low as 37 degrees, its heart rate falls from 80 beats a minute to 4 to 10 beats per minute, and its breathing rate falls to somewhere between two breaths a minutes and one breath every six minutes depending on what source you read.
But here’s the kicker, and something I didn’t know until recently. One assumes that once a hibernating animal’s metabolism is lowered, it remains lowered for the duration of hibernation. However, that’s not the case. All of the species of hibernators that have been studied wake up periodically throughout the winter and warm themselves up! Groundhogs wake up about 12 to 20 times in the hibernation season, usually for two to three days, and increase their body temperature to 98.6°F., its normal temperature during the summer. They don’t eat during these arousal times, but instead rely on deposits of stored body fat.
This is a major physiological problem because climbing back up to normal body temperature consumes a lot of energy, perhaps equal to 10 days of energy used up ordinarily during hibernation. The result is a loss of about 40 percent of their body mass before exiting hibernation.
These bouts of arousal must serve a crucial function or functions, but no one’s quite sure what. It may involve restoring nutrients in the blood, invigorating the immune system, eliminating toxic substances, and/or dealing with potassium loss. But again, it’s unclear.
I was also surprised to learn that in Pennsylvania, a groundhog only averages about 100 days of hibernation, generally from November 17 to February 25, and that males often emerge before that to wander about in search of burrows belonging to females as a sort of pre-breeding dating ritual.
So, maybe I should go a little easy on the whole Punxsutawney Phil schtick since a groundhog might indeed be wandering about at that time in Punxsutawney. But the whole shadow seeing thing? Nope, not buying that.
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| photo by John Bates |
Sightings – Common Redpolls
A flock of common redpolls finally arrived at our feeders last week, the first flock we’ve seen this winter. These tiny birds weigh less than a half ounce, but are perhaps the toughest birds that visit us in the Northwoods. They breed in far northern boreal and taiga regions from Alaska to Siberia and wander down our way only in winters when there’s widespread failure in the seed-production of spruce and birch trees. They’re a jaunty looking bird with a red beret and a black goatee, and the male gets splashed with a burst of red on his chest.
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| photo by Bev Engstrom |
I proclaim them as the toughest bird we ever see because captive studies of common redpolls in Alaska show that they’re able to survive at temperatures of -65°F (hoary redpolls are even tougher, surviving to -88°F)! They accomplish this through a series of adaptations. First, they increase their plumage - Alaskan redpoll species have 31% heavier plumage in November than in July. Second, they focus on foods that offer high energy like birch seeds. Third, unlike most birds, they stay active in low light. Prior to complete dark, they store seeds in their diverticula, which are laterally expandable sections of their esophagus, and later regurgitate these seeds, husk them, and swallow them while sheltering in dense conifer cover. Their diverticula can hold up to about 15% of their body mass of seeds, which amounts to greater than 25% of their daily caloric requirements in winter.
They also increase their muscle mass, a likely requirement given that they shiver most of the winter to create heat. And they retain heat by fluffing their feathers, remaining inactive when not eating, and allowing peripheral vasoconstriction, a fancy term for the narrowing of the blood vessels closest to the skin to prevent heat loss.
Then, like ruffed grouse, they make roosting chambers in the snow when temperatures drop to extremes at night. They do this by dropping from a tree into the snow, and then making a tunnel from 2.5 to 4 inches below the surface of the snow and 10 to 15 inches long. They break the roof in the morning to depart. During winter, they leave their roosts and start foraging before dawn.
Best of all, one study says, “Sunbathing reported.” So, if you see one laying on its back on a towel, you’ll know what it’s doing.
Chocolate and Valentine’s Day
We all know that Valentine’s Day and chocolate are inextricably linked, but I’m betting few of us know that chocolate comes from the 6- to 12-inch-long seed pods of the tiny cacao tree, and that roughly two-thirds of the world's cocoa is now produced in Western Africa, not Central America, with the countries of Ivory Coast and Ghana being the largest sources.
And most of us are unaware that for about 95 percent of chocolate's 5,000+ year history, chocolate was strictly a beverage, and a bitter one at that. Etymologists trace the origin of the word "chocolate" to the Aztec word "xocoatl," which referred to the bitter drink brewed from cacao beans. Jose de Acosta, a Spanish missionary who lived in Peru and then Mexico in the later 16th century, described it as “loathsome to such as are not acquainted with it, having a scum or froth that is a very unpleasant taste.”
Sweeteners were rarely used by the Aztecs or Maya, so the cacao paste was flavored with additives like flowers, vanilla pods, and chilies. Both the Mayans and Aztecs believed the cacao bean had divine properties, and so used it in sacred rituals of birth, marriage and death. Cacao beans were even used as currency – a rabbit, for example, was worth ten cacao beans, a slave about a hundred.
Until the 16th century, the cacao tree was wholly unknown to Europeans until explorers came to the Americas and sampled it. Legend has it that the Aztec king Montezuma welcomed the Spanish explorer (and soon to be conquering invader) Hernando Cortes with a banquet that included drinking chocolate, having tragically mistaken him for a reincarnated deity.
Once someone in Europe tried mixing cacao paste with honey or cane sugar, chocolate quickly became popular, and by the 17th century, chocolate was a fashionable drink throughout the continent, believed to have medicinal and even aphrodisiac properties. By 1868, a little company called Cadbury began marketing boxes of chocolate candies in England.
In America, chocolate was so valued during the Revolutionary War that it was included in soldiers’ rations and sometimes used in lieu of wages.
Chocolate has pleasant effects beyond its sugary taste. It contains a chemical called theobromine that is similar to caffeine, and another, phenylethylamine (PEA), that is a stimulant and facilitates the release of dopamine, the “feel good” chemical in our brain’s reward center. It also has three compounds that mimic the effect of marijuana, though in minute amounts.
So, a tiny tree, all of 15 to 20 feet tall, and with bitter fruit, still rules the world of tree fruits, particularly in mid-February when love is on the wind and also in the taste buds.
A Cold January, Yes, But Not One With Extreme Cold
I’ve heard many times over this January how we were having an old-fashioned cold winter like we used to. And I’ve agreed, but only half-agreed. Our high temperatures were consistently in the teens or lower, and so those temperatures were very much like winters in the past. But our low temperatures were consistently “only” down to around minus 20° at their worst (I know some places registered lower). In “old-fashioned” winters, we’d minimally hit minus 30°, and every other year or so hit minus 40°. So, we’ve been spared the extreme lows that historically were so characteristic of Wisconsin’s Northwoods.
Now, I know we could get hammered yet. We’ve had some extreme cold in February in the past, with the first week in February of 1995-96 taking the cake: on 2/1, temperatures at our house plummeted to minus 48°; on 2/2, minus 45°; on 2/3, minus 50°; and on 2/4, minus 46°. We heated up on 2/5 to minus 24°‚ and that felt rather warmish.
Heck, on March 7th that year, we even dropped to minus 38°!
The Wisconsin Initiative on Climate Change Impacts has, among its many maps, a map showing the change in minimum winter temperatures for December, January and February from 1950 to 2018, and the minimums for our area have increased around 7 degrees.
So, I think we need to be cautious in how we now so quickly use the terms “bitter” and “extreme”. Minus 20° is still plenty cold – I’ll be staying inside next to my woodstove, thank you very much. But in the larger historical context of our area, it’s not extreme, nor is it normal.
Celestial Events
For planet watching in February, look after dusk for Jupiter low in the southwest; however, Jupiter will be lost to our view by mid-month. Before dawn, look for Venus, Mars, and Mercury all low in the southeast.
Yesterday, 2/3, marked the midway point between winter solstice and spring equinox. We’re up to 10 hours of sunlight as of 2/7, and by Valentine’s Day on 2/14, we’ll be receiving over three minutes more per day of sunlight, perhaps the best Valentine’s gift of all.
February’s full moon occurs on 2/16 – the Snow/Hunger Moon.
Thought for the Week – “The Moment”, a poem by Margaret Atwood
The moment when, after many years
of hard work and a long voyage
you stand in the center of your room,
house, half-acre, square mile, island, country,
knowing at last how you got there,
and say, I own this,
is the same moment when the trees unloose
their soft arms from around you,
the birds take back their language,
the cliffs fissure and collapse,
the air moves back from you like a wave
and you can’t breathe.
No, they whisper. You own nothing.
You were a visitor, time after time
Climbing the hill, planting the flag, proclaiming.
We never belong to you.
You never found us.
It was always the other way round.
Please share your outdoor sightings and thoughts: e-mail me at manitowish@centurytel.net, call 715-476-2828, snail-mail at 4245N State Highway 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com.
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