Winter Robins
WINGIN’
IT
By
Kate Crowley
I am a Minnesotan who
likes winter. I like the beautiful
images of snow falling and creating landscape-scale snow globes. I like being
able to ski our trails and absorb the silence of the forest. I like the sense of hibernation too, when our
homes become sanctuaries of warmth and peace.
I even enjoy the act of shoveling because it gives me a real sense of
accomplishment. I admit that I do not have to face the daily trials of bad
driving conditions and cold cars in the
morning, which I believe are the cause of most people’s angst. So, living through December, January and
February is not a hardship for me and it usually isn’t until later in March
that I start to get spring fever.
So, it wasn’t wishful
thinking on my part when I walked past a townhome on a corner in NE Minneapolis
last Saturday and saw two American robins in the yard. I did a double take, but then stopped to
watch as they pecked at the exposed grass under a pine tree. The temperature had risen into the high 30s
and the snow was melting fast. However, try
as they might, they weren’t going to pull any earthworms out of the frozen
earth.
Finding robins in
Minnesota in winter is not without precedent.
These are not birds that have gotten their calendars mixed up and come
north far too early. These are birds
that never left.
Looking around the yard
I noticed two fairly large crabapple trees, with lots of dried fruits still
hanging from the branches. While robins
are generally ‘meat’ eaters, they will change their diet when their preferred
source of food disappears. This is when
they become ‘frugivores’ (fruit eaters).
Sumac, hackberry, and buckthorn (that invasive scourge of our forests
and gardens) are some of the other species the robins will go to for sustenance.
You have probably heard
tales of robins appearing to be drunk after eating mountain ash berries in late
winter. As they begin to thaw,
fermentation takes place with the natural sugars in the berries. A bird’s system can be overwhelmed by eating
too many of these ethanol filled fruits.
Cedar and Bohemian waxwings will do the same, but they actually have
larger-than-normal livers to help them process the fermented berries. When the birds become intoxicated they will
often fly into windows and other solid objects, leading to injury and
death. They can’t know that too much of
a good thing can bring serious trouble as they swallow the berries one after
the other.
Besides fruits or
berries, overwintering robins must have water.
Eating snow is too energy intensive for their bodies and finding open
water in a Minnesota winter can be a big challenge. The two birds I saw were in a neighborhood
not far from the Mississippi River, which remains opens because of St. Anthony
Falls, so they were in a good place for their winter sojourn.
I don’t know whether
these robins were male or female, but oftentimes the male will overwinter in an
area, giving them a head start over
other males when spring does arrive and it’s time to set up a territory and
find a mate. Females have greater nutritional
needs in order to produce eggs and raise the young, so having an abundant food
supply is especially critical to them.
Another adaptation that
helps the robins (and all other birds) who spend the winter in Minnesota is the
extra growth of downy feathers that occurs as the months grow colder. Anyone who has worn a down jacket or slept
under a down comforter knows the wonderful insulating warmth those feathers
provide. So too, do the birds find more
protection and comfort when exposed to severe winter temperatures. If the feathers aren’t enough, the birds will
shiver, thereby creating body heat for survival. But that technique is also energy intensive
and birds must have a good supply of food to replace the calories that are
consumed.
If you find any robins
hopping around your home this winter, do not expect them to eat the bird seed
you put out. They will however be
grateful for any mealworms you might provide.
Putting fruit out may not work at first because they are raised to
expect fruit to be hanging from tree branches, not lying on the ground. One man who found a flock of robins in his
yard came up with the ingenious idea of putting live mealworms into a heated
bird bath. Unfortunately a single,
dominant robin took over and wouldn’t let any of the other robins near his
stash of worms.
Most of us will have to wait to see our first robins
of the year, but you can be heartened by the fact that in only two months, the
first arrivals of the season should appear.
***Correction for last
column about the Ivory Gull. The gulls
that are most common in Canal Park in winter are Herring Gulls, not
Ring-billed, although they can be present also.
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