A
Northwoods Almanac for March 16 – 29, 2018 by John Bates
Sightings
Mary and I spotted eight Canada geese on the
Manitowish River below the Rest Lake Dam on 2/28, along with three trumpeter
swans. The swans may have been representatives of those that wintered-over
here, but the geese winter south of here, so they have just migrated back. Keep
an eye on any open water now – waterfowl are returning!
Bald eagles are rebuilding their nests, and
on average, should be incubating eggs by April 1. Mary and I have been watching
the pair that nest across the Manitowish River from our house carrying large
sticks to the nest.
Ravens
are also now beginning to nest, most often on south-facing ledges far from
humans.
On 3/4,
Sarah Krembs in Manitowish Waters observed her first chipmunk of the year.
On 3/10,
Judith Bloom observed a dozen or so Canada geese plus some
mallards in the open water at the far east end of Lake Minocqua just across
from the entrance to the fish hatchery.
On
3/11, Randy and Debbie Augustinak in Land O’Lakes
photographed a barred owl successfully hunting from their bird feeder pole.
They noted, “He swooped down on an unsuspecting vole, flew up into a nearby
tree, and down the hatch it went! Surprisingly, the chickadees don’t seem to
mind him hanging around.”
 |
| photo by Randy Augustinak |
Snow
Fleas
Warmer
winter weather always brings out armies of snow fleas, which appear as little
more than tiny black specks on the snow. They are most often seen near the dark
trunks of trees where one assumes they are enjoying a little more heat. Officially, they are called springtails and are not actually
fleas, or even for that matter, technically insects.
In the summer, hundreds of thousands of springtails can populate
one cubic meter of top soil, but since they live within the soil, they largely
go unnoticed by people. In the winter, however, they can be easily spotted
against the white backdrop of snow.
Springtails feed on decaying leaf litter and other organic
material in the soil, and play a role in natural decomposition. So, they’re a
“good” thing.
They can withstand bitter winter temperatures thanks to a glycine-rich
antifreeze protein that binds to ice crystals as they start to form, preventing
the crystals from growing larger.
Winter
Stoneflies
I received a phone call a
few weeks back from a man inquiring about what kind of flying insect he was
seeing out on the snow. I’m not an expert on insects, but from his description,
my suspicion is he was seeing winter stoneflies. There are two families of
winter stoneflies with oodles of species, so even if one had the insect under a
microscope, it would be a challenge to determine the specific species. However,
I’ve attached a photo of the most likely culprit –
.
Stoneflies
winter as larvae in streams. They’re almost always associated with clean,
well-oxygenated water, and thus are commonly used as an indicator of a healthy
creek or river.
They’re
adapted to the cold via the various sugars and chemicals they possess which
provide them with an internal antifreeze. Why they have evolved to emerge
during the winter is certainly open to speculation – are they crazy, for
instance? – but one reason may be that
there are fewer predators in early spring like birds and bats, as well as fewer
insect competitors to deal with. Still, it seems like the cons would exceed the
pros.
Many
stoneflies are “shredders,” meaning as larvae, they feed on autumn leaves that
have fallen into the water. But in late winter as emergent adults, some species
don’t feed at all, while others feed on various liquids, algae, pollen, plant
buds, or lichens.
Some
male winter stoneflies attract mates by drumming their abdomens against various
surfaces, each species having its own beat, preferred location, and drumming
surface. If a female likes the beat, she will drum back until they find one
another. Once mated, the female lays up to a thousand eggs in the water, and
the cycle begins again. So, it’s not only woodpeckers and grouse that drum to attract
mates – so do stoneflies!
Pine
Cone Willow Gall
Last week, Mary and I were
skiing when we stopped to check a map. Near the map post, we noticed a shrub
with “pine cones” on the tips of many of its branches, something we have seen
other years as well. The problem with our observation was that the shrub wasn’t
a conifer, but rather was a willow, and willows don’t produce pine cones. My
first thought was that it had to be an insect gall of some sort, but what kind?
A little research later, I found that the gall is called the “willow pinecone
gall” and is produced by the gall-midge Rhabdophaga strobiloides.
By cutting the gall apart, we could find a little larval
“worm” nestled in the center of the cone. As spring comes on, the larvae will
pupate and eventually hatch as an adult in May. The adult will fly away, but
before doing so, the female will lay an egg on the tip of a branch where new
willow leaves would ordinarily form from a terminal bud. The egg will hatch,
and the larvae will burrow into the willow stem, triggering the plant to
secrete growth hormones that alter how the leaves will grow. The leaves now
layer themselves into a cone-like structure, a bit like an onion, and the
larvae nestles into the center for the rest of the year, growing and shedding
its skin through several instars.
The mature larvae protects itself from freezing inside the
gall by concentrating a glycerol antifreeze in the bodies, and if that works,
it will emerge as an adult next May and start the process all over again.
Interestingly, there’s competition for these cozy winter
apartments. Numerous other insect species can be found in the willow pinecone
galls, including a parasitic wasp that raises its larva on the flesh of the
midge larva.
Budding
Trees
and shrubs are budding out. Pussy willows are what everyone notices first
because even with sub-zero temperatures and a foot of snow on the ground, the
buds will break. The willow flower bud is actually inside the fur coat of
silvery hairs that insulate it against the cold. The hairs trap heat from the
sun and warm the bud.
Willows
are either males or females, and it’s usually the male pussy willows that
emerge first, with the male stamens eventually warming sufficiently to produce
pollen.
Of
our three native maple trees, silver maples flower first, well before red
maples, then sugar maples. The buds on the silver maples below our house are
already swollen and seemingly ready to burst.
Camo
We
still have a bevy of pine grosbeaks frequenting our feeders, and Mary noted
that the juvenile and females are perfectly color-coordinated with the willow
and alder shrubs they often are perched in. Their russet heads and gray bodies
blend in perfectly.
Celestial
Events
The BIG event coming soon
is, of course, spring equinox, which will occur on 3/20. But actually our days
and nights will achieve equality on 3/17, and from now until late September, we
will be blessed with more daylight than night.
Spring
equinox is, of course, mislabeled. Equinox is accurate, but “spring,” well,
consumer advocacy groups could win a lawsuit on this one. Still, we typically
see our first-of-the-year red-winged blackbirds and robins around the equinox,
so these harbingers of the real spring are providing signals that spring is on the
way. But will it be HERE on March 20? Of course not. And if you are complaining
about its reluctance to truly arrive, then you need to have a consult with your
memory doctor. This is the Northwoods – recall that it often snows in early
May. So, patience is our calling, and while it’s hard to persevere, it’s
northern weather that makes this the Northwoods.
Thoughts
for the Week
In the
spring, I have counted one hundred and thirty-six different kinds of weather
inside of four and twenty hours. – Mark Twain
To be
interested in the changing seasons is a happier state of mind than to be
hopelessly in love with spring. – George Santayana
Please share your outdoor sightings and thoughts: call
715-476-2828, e-mail at manitowish@centurytel.net,
snail-mail at 4245N State Highway 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com.
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