A Northwoods Almanac for 2/2 – 2/15/2018
White-Nose Syndrome Breakthrough?
In the never-ending list of reasons for why we need scientific
research, scientists may have discovered a solution to combat the fungus that
causes white-nose syndrome in bats.
The
fungus, Pseudogymnoascus destructans, grows on the wings, snout and ears
of hibernating bats, and disrupts them as they hibernate, causing them to wake
up and burn the limited fat stores they need to survive winter.
However, the fungus is known to thrive only in
cold, dark environments (such as caves) with a strict temperature range of 39
to 68 F, so it can only affect bats during hibernation.
A team from the U.S. Forest Service, U.S. Department of
Agriculture and the University of New Hampshire recently conducted a genomic
analysis on P. destructans and identified a potential “Achilles heel” –
the fungus is highly sensitive to UV light. They found that a low dose exposure for just a few seconds of
the UV light resulted in a 15 percent survival rate of the fungus, and a moderate dose led to just a one percent
survival.
The trick now is determining how to best use the UV light
throughout the winter on a large-scale without disrupting the animals’
hibernation.
Sightings – Clark’s
Nutcracker!
Dan Carney in Hazelhurst sent me a
photo of a Clark’s nutcracker that was seen a few weeks ago pecking at a deer
carcass on a farm near Tomahawk. Clark's nutcrackers inhabit the high mountain regions of the
western United States and Canada, preferring coniferous forests dominated by
large-seeded pines. So, seeing one in north central Wisconsin is a very rare
event. The Wisconsin Society for Ornithology keeps records of rare bird
sightings, and only five reports of Clark’s nutcrackers have been verified in
Wisconsin, the last one in 1973 in Manitowoc.
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| photo by Pete Ventener |
They’re known to eat carrion, insects, and small animals,
however, they’re truly specialists on pine seeds. In fact, several pine species depend on nutcrackers for
their seed dispersal and have evolved specialized cone and seed traits for this
interaction, including whitebark, limber, Colorado piñon, single-leaf piñon,
and southwestern white pines.
Clark’s
nutcrackers cache vast numbers of seeds for the winter. In one study,
nutcrackers stored 22,000 to 33,000 seeds of Colorado piñon pine, while in
another study, two individuals hid 35,000 seeds and 98,000 seeds of whitebark
pine respectively. Consider the incredible spatial memory they must have to
then find all those seeds.
Clark’s nutcrackers were one of three new bird species described
by Alexander Wilson from specimens collected during the historic Lewis and
Clark expedition. Clark's Nutcracker was feeding on pine seeds and was mistaken
for a woodpecker when first seen by Captain William Clark on August 22, 1805.
The last time Mary and I saw a Clark’s nutcracker was in
March 2005 along the south rim of the Grand Canyon, a rather far cry from
Tomahawk!
Sax-Zim Bog
Earlier in January, the North Lakeland Discovery Center Bird
Club visited the Sax-Zim Bog in northeastern Minnesota and found 28 species of
birds, including three species of owls – great gray, northern hawk, and snowy.
They also observed other rare birds like a black-billed magpie and a
black-backed woodpecker. Bird club member and ace photographer Mark Westphal
took some superb photographs, of which I’ve shared two in this column – a great
gray owl and a black-backed woodpecker.
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| photo by Mark Westphal |
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| photo by Mark Westphal |
Other Sightings
It’s been an excellent winter for
pine siskins, common redpolls, and pine grosbeaks. We have a flock of 20 pine
grosbeaks consistently at our feeders, along with good numbers of siskins and
redpolls. Many other folks are reporting large populations as well at their
feeders of all three species. Missing in action continue to be purple finches,
evening grosbeaks, and bohemian waxwings.
Common
redpolls only weigh around ½ ounce, and are astonishingly tough little birds.
They breed worldwide in the boreal and taiga regions of the Arctic, so they
come a very long way to share our winter backyards. In North America, they
irrupt in large numbers only in alternating years and only in even-numbered
years, with one exception, 1969. The irruption cycle is driven by a widespread
failure in spruce and birch seed-crop production which forces these birds to
winter farther south.
 |
| photo by Bev Engstrom |
They
are known to travel east and west during the winter as well. One redpoll banded
in Michigan was subsequently recovered in eastern Siberia, while redpolls
breeding in Alaska have been recorded wintering in the eastern U.S.
In
captive studies, common redpolls in Alaska were able to survive at temperatures
of minus 65°F, while hoary redpolls survived at minus 88°F. That seems
impossible to me!
Conversely,
redpolls can’t tolerate high temperatures. As temperatures warm, captive birds
became less active, eat less, drink more, and pluck their body contour and down
feathers. Thus, climate change doesn’t bode well for them.
Snow Statistics
The water equivalent of snow
is more variable than most people realize. For instance, 10 inches of fresh
snow can contain as little as 0.10 inches of water, or as much as 4 inches of
water, depending on crystal structure, wind speed, temperature, and other
factors. The majority of new snowfall in the United States, however, contains a
water-to-snow ratio of between 4 percent and 10 percent.
Snapper
Hibernation Crazy Facts
In the winter snapping turtles hibernate in
shallow water, buried in the mud in places which don’t freeze to the bottom.
During that time their body temperature is reduced to about 34°F, and they
rarely move, although some have been observed moving under the ice. In northern
areas, hibernating snapping turtles don’t breathe through their lungs for more
than six months while under the ice. They can, however, get oxygen by pushing
their head out of the mud and allowing gas exchange to take place through the
membranes of their mouth and throat, a process known as extrapulmonary
respiration.
2017 Weather on the Record Books
According
to NASA and the National Oceanic and Atmospheric Administration, last year was the
second or third warmest year on record, depending on which agency’s records you
examine, because each has its own method for its calculations. One warm year is
not necessarily cause for concern, but the trend is. The past three years were
the warmest three ever recorded, and seventeen of the 18 warmest years in the
data have come
since 2001. This decade is on track to be warmer than the 2000s, which were
warmer than the 1990s.
Snowy
Owl Update
Four
snowy owls are currently being followed by researchers in Wisconsin via their
transmitters. Two are wintering close to one another in the Buena Vista
grasslands in central Wisconsin. Although they have largely avoided each
other, both have been perching on the same center-pivot irrigation rig at
different times. The two young males have been sharing a large area, about
5,400 acres. One sticks to a core area of about 500 acres, while the other
wraps around it while generally not intruding on it.
The other two snowies are
on territories elsewhere in
Wisconsin. One female is using a roughly 760-acre territory southwest of Green
Bay, around which she moves a lot during the day. The other one, a male, has a
bit more wanderlust, tracing a vaguely inverted J path north of Madison that
stretches some 12 miles from end to end, and he’s more typically nocturnal in
his movements.
Celestial
Events
February
3 marks the mid-point between winter solstice and spring equinox, though as we
all know, spring equinox doesn’t mean spring is arriving up here. We’re up to
10 hours of daylight as of 2/7. On 2/8, look before dawn for Mars about 4
degrees south of the waning crescent moon. On 2/11, look before dawn for Saturn about 2
degrees south of the moon. New moon on 2/15.
Thought for the Week
“Winter is not a season, it's an occupation.” – Sinclair Lewis
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