A Northwoods
Almanac for January 9 – 23, 2015
Bald Eagle Watching
In 1969, Wisconsin was one
of the first states to ban DDT, which scientists had clearly linked to massive
eagle deaths, helping to trigger a national ban of DDT in 1972. The eagle population
had crashed to only 487 nesting pairs in the continental U.S. from an estimated
100,000 nesting pairs in 1782, when America adopted the bald eagle as its
symbol.
It’s been an amazing
turn-around. Bald eagles were removed from Wisconsin’s endangered list in 1997
and from the federal list in 2007. In 2013, a record 1,343 occupied eagle nests
were documented in 67 of Wisconsin’s 72 counties.
In winter, most of
Wisconsin’s eagles migrate to where the food is, and the best restaurants are
near dams and power plants, which provide open water for the eagles to fish. Because
so many eagles congregate at these sites, eagle watching events are now held in
Cassville, Prairie du Chien, and Ferryville on the Mississippi River, Sauk
Prairie on the Wisconsin River, and the Fox Cities along the Fox River between
Neenah and Kaukauna.
Here’s the lineup of
events: “A Day with Eagles along the Fox River” will be held on January 17. The
Fox Cities have identified 16 prime viewing spots in Kaukauna, Combined Locks,
Little Chute, Kimberly, Appleton, Neenah, and Menasha. Sauk Prairie’s 28th annual “Bald Eagle
Watching Days” also takes
place on Jan. 17, while Cassville’s is on Jan 24-25, Prairie du Chien’s on
Feb. 28, and Ferryville’s on March 7.
Snowy Owl Update
There are now an estimated 226 snowy owls across
Wisconsin – see the eBird map at http://bit.ly/1Hi9NWL. There may be some
duplication in the count, so the number is truly an estimate. However, using
the same counting techniques, we had 173 snowy owls as of this date last year,
making this the record winter for snowy owls in Wisconsin.
Across the U.S., this year’s snowy owls, compared to
last year’s birds, arrived earlier, have a lower proportion of juvenile birds, are
located more in the central/western Plains and less in the Northeast, and have
stayed further north aside from a couple pioneering birds that have been seen
Kansas and Oklahoma.
There’s been some heated discussion about folks
getting too close to the owls. For the ethical way to view these birds, see http://wsobirds.org/about-wso/code-of-ethics.
If you do see a snowy owl, telling the males from the
females is as much an art as a science. Males are usually much lighter, but not
always. And snowies tend to get lighter with age, but not always. As a
generality, the whitest birds are usually adult males, while the darkest birds
are usually immature females. But if you see a bird with moderate markings, the
jury is out. The key points to look for are the extent of the white bib on the chest (larger in males), the darkness at the nape of the neck (dark
in females, mostly white in males), and the barring of the tail (some complete, or nearly complete bars on
females; males with mostly broken bars, or nearly complete at best).
Locally, Sarah Krembs in Manitowish Waters heard that
there were owls in the Antigo area, so she and her father took a drive. They
found two snowies in the fields just north of Antigo – see Sarah’s excellent
pictures! She noted, “One was just outside of Antigo on a telephone pole on Hwy
64. That was the dark one, a female, right? Then, the other one I spotted on
our way back home just as we were leaving Antigo on Hwy 47. This owl was
perched on the irrigation sprinkler system way out in the middle of the field. We
pulled over and watched it for a bit. Then it flew closer to the highway and
sat on the snow for a minute or two. I couldn't tell if it was eating anything.
And then he went and flew to the very end sprinkler, which was the one closest
to the highway. I got to take pictures and watch him for a long time. When he
would look at us with those yellow eyes and I was seeing him through the
binoculars . . . wow . . . blood-chilling. Very impressive. This guy was much
whiter...male, correct?”
Sarah’s gender ID’s were spot on, given the best
generalities we can go by.
There are no birds locally to observe, at least that
I’m aware of. But a road trip like Sarah’s could turn up a number of owls –
that’s where the adventure comes in.
Minocqua Christmas
Bird Count Totals
The Minocqua Christmas Bird Count, which took place
on 12/20, tallied 1,418 birds. This ties for the record high over the 17 years
that this CBC has been conducted. Counters also recorded a total of 28
species, the record high. Another first was a report of a Cooper’s hawk. The total
number of species recorded over all Minocqua CBC’s now stands at an impressive
53 species of birds. However, during any given count, the Minocqua CBC averages
644 birds of 20 species.
Christmas Bird
Counts: One Difference between Madison and the Northwoods
What does being 250 miles south of our area mean to
wintering birds? Well, Madison held its Christmas bird count on 12/20, the same
day as the Minocqua count, and they tallied 92 species. Whereas Canada geese
are a rare winter sighting up here, within Madison’s count area (a circle 15
miles in diameter), they counted over 15,000. They also tallied 2,438 mallards,
897 tundra swans, and 903 common mergansers, as well as birds we seldom see in
the Northwoods like 46 tufted titmice and 223 red-bellied woodpeckers. On the
other hand, they also had 4,217 starlings and 2,706 house sparrows, which we
fortunately saw none of.
So, to state the ridiculously obvious, cold, ice, and
snow matter a great deal to wildlife. If you want the real extremes, the
Christmas count in Barrow, Alaska, typically turns up zero species, or, perhaps
in good year, a raven. Of course, they have about two hours of semi-light in
which to see anything, and the normal windchill is somewhere around -70°F. Try
birding in those conditions some day.
On the other hand, the record number of species for
the one-day Christmas count is 250 in the Matagorda
County-Mad Island Marsh count circle around Matagorda, Texas. Counting along
the Gulf Coast must be a magical experience. One counter in southern Florida
talked about tallying 30 species before they even left the parking lot. Eighty
degrees in December makes just a wee bit of difference!
Surviving Cold, Redpoll Style
This week’s sub-zero cold spell is par for the course in
a Northwoods January, though to listen to the hyperbolic news reports, you’d
think we might die if we even stuck our noses outside. Mary, Callie, and I
snowshoed three miles on Monday when it was -5° with a windchill of -30° and
somehow survived. Granted, though, we wore a lot of clothes and came inside
after an hour and half.
Wintering species of
wildlife don’t possess those options. However, one tiny bird has winter all
figured out and puts anything we humans can tolerate to shame. The common
redpoll has just arrived from its northern breeding areas at many local
feeders. This tiny bird breeds circumpolarly, meaning it circles the globe in
far northern regions from Norway to Russia to Alaska to Greenland. They’re
dapper little birds, distinguished by their red berets and their black goatees,
while the male also washes his chest in raspberry juice.
Redpolls only weigh about
½ ounce and stretch out five inches. Staying warm on -20°F nights can be a profoundly
difficult chore given how little fat and fuel there is in those little bodies
to burn overnight. One survival strategy is to eat, and eat a lot. Redpolls
eat the equivalent of 31–42% of their body mass each day, particularly foraging
for the small, high-energy seeds of birches and alders, as well as conifer
seeds, various grasses and sedges, and a wide range of weeds. We purposely
don’t cut down our garden plants that have gone to seed in the fall so they
provide food for winter birds like the redpolls.
Another winter survival strategy they utilize is to
store seeds in their diverticula – laterally expandable sections of their
esophagus – prior to further digestion. Redpolls gather seeds quickly in the open,
storing them in their diverticula for later regurgitation, husking, and
swallowing. This way they can shelter in dense conifer cover and save
significant energy at times of intense cold.
Their diverticula
holds up to two grams of seeds, or about 15% of their body mass. This amount
gives them over 25% of their daily caloric requirements in winter. They also
consume a lot of grit, which is why they’re often seen on the edge of roads
picking up sand and gravel, presumably for minerals. They’re very social – flocks
of up to 50 individuals aren’t unusual. One birder near Ashland recently
reported seeing a flock of 250 redpolls. So, watch for them along the roads and
slow down – they are not at all adapted to traffic and much too easy to hit.
Other strategies they employ for winter survival
include retaining heat by fluffing their feathers, remaining inactive, seeking
shelter, and allowing peripheral vasoconstriction. Their plumage structure apparently
is also better for insulation than many other species, and they add feathers in
the winter – wild Alaskan redpoll species had 31% heavier plumage in November
than July. They also roost communally – flocks of approximately 1,000 birds have
been seen roosting in spruce. Most remarkably, they also make roosting chambers
in the snow. They can drop from the trees into the snow and make a tunnel 10 to
15 inches long and 2 to 4 inches deep, breaking the snowcap in the morning to
begin feeding.
These birds aren’t just tough – they’re astonishingly
hardy. From captive studies, common redpolls in Alaska are able to survive at
temperatures of -65°F, while hoary redpolls can handle -88°F.
Celestial Events
As of
1/10, our days will be growing longer by two minutes a day. As for cold, on
average, January 16th through the 20th mark the coldest
days of the year in our area. On 1/16, look before dawn for Saturn about 2
degrees south of the waning crescent moon.
Please share your outdoor sightings and thoughts: call me
at 715-476-2828, drop me an e-mail at manitowish@centurytel.net,
or snail-mail me at 4245N Hwy. 47, Mercer, WI 54547.
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