A Northwoods Almanac for 2/16 – 3/1, 2018
Sightings – Northern Shrike and
White-throated Sparrow
Nancy Anderson spotted a
northern shrike in her yard on 2/3 and noted: “We have many common redpolls at
this time here in Lac du Flambeau, so we're thinking hunting is good for this
predatory song bird.” She’s right. Around one’s home, northern shrikes are a
short-lived thrill to spot. While they’re uncommon and beautiful, they are
there for one reason only – to scout your feeders for their next meal.
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| photo by Nancy Anderson |
Their
Latin name, Lanius excubitor, means “butcher watchman,” a fitting tribute
to their skill set, because they typically sit and wait to spot prey from an exposed
hunting perch. We’ve watched them sit motionless above one of our feeders for
many minutes waiting for a mouse or vole to venture from a hole.
The
literature says they have the ability to spot motionless birds “frozen” on
branches and to capture them before they move, which is not good news for the
many songbirds that utilize this defense. They’re not strong direct flyers, but they don’t give up
easily, often following prey into thick bushes. They’re also known to take down
birds larger than themselves, including robins, jays, and doves.
They
kill birds and other vertebrates by biting the nape of the neck and “disarticulating
cervical vertebrae.” Northern shrikes have bilateral, subterminal tomial teeth
on their upper bill which appear to penetrate between adjacent vertebrae,
quickly damaging the prey’s nerve cord, thus paralyzing and killing it.
Bilateral:
both sides. Subterminal: almost at the end. Tomial: a notch on the edge of the
beak. They’re not “teeth” since no bird has teeth, but they’re like a tooth
along each side of the beak. These “teeth” make for a prey’s quick death, which
as any hunter knows is a good thing.
There
are frequent reports of shrikes killing in excess of their food requirements.
Bird banders tell me of shrikes getting inside their traps and killing all the
birds. But shrikes will store food, so they’re just harvesting what’s available
for later use, no different than humans putting food in the refrigerator for
later meals.
On another note, we have
a single white-throated sparrow
spending the winter at our feeders. As a ground feeder wintering in deep snow
country, this white-throated sparrow has to be severely challenged to survive.
I wish I could ask him why he didn’t migrate to a warmer climate with less snow
back in November.
The white-throat’s winter
diet is mostly grass and weed seeds, thus the need to winter further south. But
they also eat fruits of sumac, grape, highbush cranberry, mountain ash, and
rose hips, all of which (except sumac) we have in our yard, so perhaps that
explains this lone male staying put.
They also know how to dress for
the winter – a white-throated sparrow has some 2,500 contour or body feathers
in winter compared to summer's 1,500. So, the cold may not be too much of an
issue for this little guy.
Update on the Clark’s Nutcracker
Mary and I were able to visit with a very
gracious couple in Oneida County who have had a Clark’s nutcracker visiting
their yard since the first of the year. The nutcracker is drawn to a deer
carcass they have hanging from a tree, as for that matter are chickadees,
nuthatches, and other birds – fat equals high energy in a cold winter.
 |
| photo by John Bates |
As I wrote about in my last column,
the nutcracker is a very rare visitor to Wisconsin, so this is a big deal in
the birding world. The question that always arises when a bird is so far from
its normal range is what will happen in the spring? Will the nutcracker know
how to migrate back to its normal Rocky Mountain breeding habitat, or will it
look around and say “What now?”
One day it will
disappear from its winter restaurant, and unless banded and recovered, we’ll
never know the end to the story.
Great Backyard Bird Count
The
21st
Great Backyard Bird Count
(GBBC) will take place February 16 to 19. This global event provides an
opportunity for bird enthusiasts to contribute important bird population data
to scientists so they can record changes over time. To participate, bird
watchers count the birds they see for at least 15 minutes on one or more days
of the count, then enter their checklists at birdcount.org.
Over
its 3-decade history, the GBBC has expanded from a 2-country count (U.S. and
Canada) to a global event. During
the first GBBC in 1998, bird watchers submitted about 13,500 checklists from
the United States and Canada. Twenty years later in 2017, an estimated 240,418
bird watchers from more than 100 countries submitted 181,606 bird checklists and
reported 6,259 species – more than half the known bird species in the
world.
The
rules are easy:
Count
birds for at least 15 minutes on any of the days or all: Feb 16, 17, 18, or 19.
Keep
track of how long you counted and if you’re walking, how far you walked.
Go to your favorite spot or any spot. It doesn’t have to be a backyard – it
can be anywhere.
Start
a new count for each new place or time.
This
can be as easy as you want it to be – lots of folks simply look out their
windows and count their feeders from the warmth of their homes. And in the
Northwoods in February, you’re likely to see more birds that way than taking a
walk or driving around looking for birds. Our Christmas bird counts have proven
this many times over. Please consider joining the count!
Nesting Has Begun!
As hard as it may be to believe, several bird species should now
be nesting. Both great horned owls and gray jays are known to be incubating
eggs by late February. Gray
Jays nest during late winter in cold, snowy, and apparently foodless
conditions, with eggs incubated at temperatures as low as -22°F. Nest building
can begin in February, with clutches initiated as early as Feb 22 in Algonquin
Park, Ontario, which is almost exactly the latitude of Minocqua. Interestingly,
second broods or replacement nests are not attempted in May or June, the breeding
period used by other boreal passerines. Gray jay nestlings are being fed before
80% of our migratory birds have even returned.
For
great horned owls, females are able to maintain their eggs at incubating
temperatures near 98°F, even when the ambient temperature is more than 70°
colder. They’re able to incubate eggs successfully when outside
temperatures are below -27°F. In one study, the eggs withstood the absence of
the incubating female for 20 minutes at
-13°F when the female joined her mate hooting at a neighboring male.
Winter Birdbaths
I was asked whether winter bird baths are a good idea or not.
It’s been said that birds can get their feet wet in these baths, and then
freeze to the metal rods on bird feeders. I have heard of this occurring on two
occasions over the last 25 years, but that’s a pretty small percentage. My
sense is that the advantages far outweigh the risks. After all, birds can get
their feet wet in a host of other ways in the winter – we do have open water in
many creeks, and dripping icicles are common drinking sites for birds – so,
bird baths are not exposing birds to some novel occurrence.
The simplest way to provide water in winter is to set out a very
shallow plastic pan at the same time each day, and bring it in when ice forms.
If you want to keep a birdbath ice-free, some birdbaths come with built-in,
thermostatically controlled heaters.
Some simple, common sense rules include never adding antifreeze
to the birdbath – it’s poisonous to all animals. Don’t use a sugar solution,
either: it can saturate and matt a bird’s feathers leaving it susceptible to
hypothermia. Just use plain water.
It’s also important to change the water every day or two.
Bathing birds may leave behind dirty feathers and droppings, making the bath
increasingly unsanitary for other birds.
Celestial Events
The new moon occurred yesterday, 2/15.
Check the night sky tonight because this is the time of year when the brightest
accumulation of stars can be seen annually. Look for constellations like Orion,
Sirius, Gemini, Auriga, and Taurus, all of which contain first-magnitude stars.
Venus rises before dawn late in the month
in the southwest, and will climb higher and higher as the spring returns. For
right now, however, the morning planets are Saturn, Mars, and Jupiter, all of
which can be seen in the southeast before dawn.
As of 2/27, we will be receiving
over 11 hours of sunlight – hooray! It’s getting lighter every day.
February has no full moon this year.
The next full moon occurs on March 1, and like January, March will have two
full moons, the second one occurring on 3/31.
Thought for the Week
“We ourselves seldom
comprehend the moment at hand. So, we turn to history, the one element of our
lives it is possible to fix on. Or we turn to principle. Or we turn to nature.
There we find, amid the silence and mystery, order and structure, the sense
that life is not simply random.”
– Paul
Gruchow
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