A Northwoods Almanac for 1/24 – 2/6/14
More Benefits of Extreme Cold
January is giving us another hit of cold
weather, though not nearly as intense as two weeks ago. As in my last column,
I’m again singing the praises of the cold, despite the difficulty it poses for
all of us. The reason is simple: extreme cold kills numerous invasive species.
Here’s the story.
Insects
employ three strategies to survive winter temperatures:
1- Some avoid the cold altogether by
migrating (think monarch butterflies and green darner dragonflies), or some
aggregate together as adults in sheltered locations to stay warm (think honey
bees).
2- Some don’t let themselves freeze by
making chemicals that allow them to supercool below the freezing point of water
(think these three invasive species: emerald ash borer, forest tent
caterpillars, and gypsy moths).
3- Some actually freeze, but survive by
using special proteins to regulate the way their body freezes and to minimize
damage to their cells. One way this is done is to use extracellular freezing, a
process by which ice-nucleation occurs harmlessly outside of the cell walls
(think woolybear caterpillars, which actually employ all three strategies).
4- And some insects employ a combination
approach – Asian lady beetles aggregate in sheltered areas, often in the walls
of our homes, and also can supercool.
The species that
use supercooling are tolerant of the cold, but only to a certain point, and
then they die, which is where extreme cold becomes hugely beneficial. For
instance, emerald ash borers, an Asian native which so far has killed about 50
million ash trees in the Upper Midwest, start dying at -10°F. But when temperatures dive to -20°F, 50
percent usually die. And if temperatures drop to -30 below, 98 percent perish!
Another
example are gypsy moths whose wintering egg masses begin to die as soon as
temperatures get around -17°F.
Asian
longhorn beetles, an invasive that kills maples and other hardwoods, winter as
larvae in the center of trees, but freeze at -14°F.
As
for forest tent caterpillars, their egg masses can only supercool to -22°F,
whereupon they die.
The
invasive that I’m most fearful of because of my love for hemlock trees is the
hemlock wooly adelgid, which has killed millions of hemlock trees out East, and
is coming our way. The wooly adelgids, a tiny insect the size of a period in
one of these sentences, dies when temperatures hit -5°F.
One
last reason to cheer extreme cold: ice cover this winter on the Great Lakes is
projected to cover over 60 percent of the surface waters. Ice vastly reduces
evaporation rates, reducing loss of water, which has plagued our lakes in
recent years. It also reflects the sun, keeping the water chilled, and thus
further helping to reduce evaporation since warm water evaporates more quickly
than cold water.
So,
while our bodies are shivering, and we’re complaining about not living in
Arizona, our brains should be telling us to celebrate the return of a true
northern winter. The extreme cold reinforces the range limits on a host of
plants and insects, and for that we should be cheering.
Now
if research could only show that extreme cold kills ticks . . .
Wool
While
extolling the virtues of extreme cold, I would be remiss to not also extol the
virtues of today’s merino wool products that Mary and I use daily to keep the
cold at bay. Today’s wool socks, shirts, underwear, and trousers are not at all
like your grandparent’s woolen wear. I wear a wool long-sleeve zip-neck t-shirt
under my shirt virtually every day during the winter, and I love them. They’re
very soft, don’t itch, don’t hold moisture like cotton, and don’t hold onto
odors. In our opinion, wool far outperforms all other winter activity
materials, from polypropylene to fleece. In fact, cold
weather research shows that because of wool's effective moisture management,
you maintain a lower and more stable core body temperature when wearing wool
next to your skin instead of synthetics.
We’re
flat-out sold on wool. We’re not on these manufacturers’ payrolls, but we recommend
the following companies: Smart Wool, Ibex, and Icebreaker.
Pancake Ice
Several
weeks ago, Gary Theisen sent me a photo of "frazil" ice at Lake of the Falls near
Mercer. Frazil ice forms in fast moving, supercooled water that is coursing too
rapidly for the ice crystals to freeze together into a sheet of ice. The
frazil ice is basically slush which is herded by winds and currents into globs. In
Gary’s photo, the frazil ice had formed into circular pancakes that looked like
white lily pads made of ice. The pancakes can be up to 10 feet across and 4
inches thick. The raised rims occur when the pancakes collide together like
bumper cars and the edges get bashed up, or from the slush that gets splashed
onto the edges and freezes to gradually form a rim.
Black Moon Rising
January
provides us with two occurrences of a new moon within the month, something
known as a “black moon,” a term I’d never heard before. This is analogous to
the definition of a blue moon, which is when a month has two full moons occurring
within it. The two new moons this month occur on 1/1 and 1/30.
Sightings – Woodpeckers and Evening
Grosbeaks
Sharon and David Lintereur have been keeping records since 2004 of birds
that come in to their feeders, and this winter is the first year that they have
a pair of red-bellied woodpeckers that come in every day. Sharon also notes, “We
have never had so many hairy woodpeckers as this year. We have downies and
pileateds as well. This is the year for woodpeckers.”
Linda Novak in Presque Isle appears to be the only person in our area who is enjoying
evening grosbeaks at her feeder. She sent me some photos and noted, “We usually
get 30-50 evening grosbeaks and hundreds of finches competing for food on our
ledge every morning! They used to dine separately because the grosbeaks
would push them off; now there are way too many finches, so they dine
together.”
Celestial Events – It’s Getting Brighter!
The big news in the heavens is the
gradual return of more daylight. As of 1/26, we’ll be receiving 9 hours and 29
minutes of daylight, up from our low at the winter solstice of 8 hours and 39
minutes. So, we’ve regained 50 minutes! As of 1/10, days were growing longer by
two minutes, and by 2/3, our days will be growing longer by three minutes every
day, and counting. Before you know it, it will be spring equinox, which rarely
has had anything to do with actual spring, but will mean 12 hours of daylight.
Snowy Owl Update
As of 1/11, the count for snowy owls in
Wisconsin now stands at around 219. One birder took a drive on 1/19 in the
Dorchester and Abbotsford area (far western Marathon County and eastern Clark
County), starting at 8 a.m. and finishing around noon, and tallied ten snowy owls
(two in Marathon Co. and eight in Clark Co.). Then, on his way back to the
Wausau area, he found another snowy in the Milan area, two more right along
Highway 29 near Edgar and Marathon City, and last of all, one located at the Central
Wisconsin Airport in Mosinee. So, he ended the day with a total of fourteen
snowy owls between Marathon and Clark Counties!
The Pleiades
The Pleiades star cluster – also known as the Seven Sisters– is visible from virtually every place on the
globe. It can be seen from as far north as the north pole, and farther south
than the southernmost tip of South America. It looks like a tiny misty dipper
of stars. If you’re familiar with the famous constellation Orion, it can help
you be sure you’ve found the Pleiades. Draw a line through the three stars of
Orion’s Belt to the right – and you come to a V-shaped pattern of stars with a
bright star in its midst. The V-shaped pattern is the Face of Taurus the Bull. The
bright star in the V – called
Aldeberan – depicts the Bull’s Eye. A
bit past Aldebaran, you’ll see the Pleiades cluster, which marks the Bull’s
Shoulder.
To see the cluster well, you must be willing to spend time under
a dark, moonless sky. Astronomers say that eyes dark-adapted for 30 minutes are
six times more sensitive to light than eyes dark-adapted for 15 minutes.
I’ve read that the Greek name “Pleiades” probably means “to
sail.” Supposedly in the ancient Mediterranean world, the day that the Pleaides
cluster first appeared in the morning sky before sunrise announced the opening
of the navigation season.
Final Thought “A
universe of 50 billion galaxies blowing like snowflakes in a cosmic storm is
astonishing, but even more astonishing are those few pound of meat – our brains
– that are able to construct such a universe of faint light and hold it before
the mind’s eye, live in it, revel in it, praise it, wonder what it means.” –
Chet Raymo
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