A Northwoods Almanac for July 11 – 24,
2014
Bird Song Diminishing
In
mid-July, many people wonder why the woods become so quiet. It’s relatively
simple – male birds sing loudest and longest during their initial breeding and
territory establishment, and then to maintain their pair bonding and their
territories. But once nesting has been successfully completed, most birds will
only occasionally sing, if at all, and the woods become oddly silent. The birds
are still present, though. In fact, there are far more birds in mid-July due to
all the fledged juveniles than during early June when singing was at its peak.
But for all but a few species, the necessity to sing is now gone, and thus
quiet descends from the treetops rather than song.
A Bear Story With a Message
Jim
Frandy has lived all his life in the Northwoods, but he never thought he’d be
wrestling a bear. Two weeks ago, he did, albeit just a cub.
Here’s
the story: Jim was sitting in a chair at 5:30 A.M. looking out a window at his
home when something ran by so quickly he couldn’t tell what it was. He went out
into his yard and heard some banging and smashing in the woods. Soon the source
appeared – a bear cub with a peanut butter can stuck on his head. The bear was
running fast and banging into anything that got in its way. It even ran into an
ice shack.
Jim’s
wife, Jayne, called Mark Naniot, the wildlife rehabilitator at Wild Instincts
near Rhinelander, to see if he would come out to handle the situation, but Mark
couldn’t get there until later that morning. His advice was this: get a
blanket, throw it over the bear, and see if he could get it into a cage.
Jim
got a packing blanket from his garage, stepped out onto the driveway, and the
bear cub ran across the gravel road about 50 feet ahead of him. Jim had no idea
what to do, but instinctively made a “bahhing” noise, a bit like a sheep. And
the cub stopped running. Jim made the noise again, and the little cub started
walking towards him. He continued making the sound until the cub walked right
up to him, and he was able to toss the blanket over its head. He then fell on
the cub and held it down, though the cub was none too happy about this. Jim
grabbed the can and tried to wrestle it off, but the can had a metal ring around
the top, and it was stuck hard.
Meanwhile,
Jayne called Mark Naniot again. Mark suggested they get the bear into their dog
kennel, which they did, and they took it into their garage.
Soon
after, the cub figured out how to work the can off its head. But before they
could haul the kennel outside to release the bear, the cub had thrust its head
into the can again, and the can was stuck once more.
They
hauled the kennel outside, opened it, and as the cub started to come out, Jim
straddled it. With welding gloves on, he managed to jerk the can off. He
stepped aside, and the cub sprinted out of the kennel and ran up the nearest
tree.
All
this time they were aware that the sow might be near and might be taking a keen
interest in what they were doing. However, she never appeared.
Jayne
was able to get a short video of the cub racing out of the kennel. I’ve uploaded
it onto my blog if you’d like to see it (manitowishriver.blogspot.com).
The
can was a six-pound container of Peter Pan Creamy Peanut Butter. It’s a good
reminder that our trash can cause an unintended array of problems for wildlife.
Mosquito Impact on Nesting Songbirds?
With the mosquito population at such
a zenith, I’ve wondered what their impact is on nesting songbirds. I wouldn’t
be caught dead out at dusk, but the birds have to sit calmly on their nests all
night and withstand whatever the mosquitoes bring to bear.
It turns out that there’s very
little data on the impact of mosquitoes on songbirds, but lots on whether
mosquitoes are infecting songbirds with West Nile Virus.
However, I did find one study in
particular (“Mosquito Landing Rates on Nesting American Robins (Turdus
migratorius),” 2007, Sean M. Griffing, et al, Smithsonian Environmental
Research Center, Edgewater, Maryland) that provided some insight, at least into
robins. The researchers were able to film nesting robins for 24-hour periods
with infrared cameras over the course of 14 days, beginning with the day when
all their eggs had hatched. They found that some female robins receive
2,000-6,000 mosquito landings during this period. They were, however, unable to
determine the fraction of those landings that led to successful bites.
The adult robins were able to
protect themselves on the nest by tucking their heads under their feathers and
sealing their feet in the nest material. Thus, bare areas were protected from
exposure.
The birds only occasionally
exhibited anti-mosquito behavior in the form of feather preening and the
attempted ingestion of the mosquitoes.
The bottom line for me – the
researchers did not note any birds driven from their nests during this portion
of their nesting cycle. Does this hold true for all birds? I’ve no idea, but it
suggests that songbirds likely have effective means to handle swarms of
mosquitoes during the breeding season.
Eagle Nesting Success Down
The pair of eagle chicks in the nest
across the river from our house apparently died in the last few weeks for
reasons unknown. I’d heard that eagle reproduction was down in general this
year, so to find out more, I emailed Ron Eckstein, retired DNR wildlife
biologist who has been involved in the banding of thousands of Wisconsin eagles
over the last 30 years. Ron still volunteers to do the eagle flight counts
every June, and while he hasn’t summarized all his flight notes yet, he says, “the
preliminary look is reduced nest success and late, small young. Productivity
was particularly bad on the Apostle Islands and on large inland lakes. It
seems that the very late ice out on these bodies of water caused some pairs of
eagles to abandon nests to search for food.”
Ron
is scheduled to complete his report by the end of July, so I’ll relay his data
when I get it.
Sightings – Osprey, Porcupine, Common
Grackle, Update on Doe with Quills in Its Nose, Great Blue Heron, Baby
Snappers, Fawns Nursing, and Trumpeter Swan Cygnets
Sharon and David Lintereur sent me a
photo from 7/6 of an osprey perched on its platform nest along Hwy. 8. Over 80%
of ospreys in Wisconsin nest on artificial platforms.
Mary
Rodman took a walk in early July in Powell Marsh and was greeted by a baby porcupine
that had no fear of her and allowed her to spend some time observing it.
Mary also
sent me a photo of a partial albino common grackle, a bird she said she had stalked
it for two days before finally getting a few photos. She spotted it on Mamie
Lake on the Cisco chain.
Jim
Swartout sent me an update and photo on 7/3 of the doe he’s been observing that
had seven porcupine quills in its nose on 6/13. I’m happy to report that he
noted, “The doe still has one quill remaining three weeks after her encounter
with a porcupine.” The question remains as to whether the others broke off and
could still cause her problems, or whether they somehow worked their way out.
Angie Fox
sent me three photos of a great blue heron eating a chipmunk in her front yard.
Herons are opportunistic feeders, and apparently chipmunks are as tasty as
fish.
Finally, a
pair of trumpeter swans nesting at Powell Marsh successfully hatched four
cygnets sometime in the last week of June. This is the first pair of trumpeters
that we have seen nesting on the main flowage in the 30 years we’ve been
birding at Powell.
Larch Casebearers
Robin
Franks sent me a note on 6/22 saying she had just paddled down Lost Creek and
had seen many, many tamaracks that appeared to be dead. She noted, “The river
banks are just brown the entire trip from Hwy 155 to just before Big St.
Germain Drive.” She, of course, wondered what was going on.
I
recommended she contact a forester in the area, and Linda Williams from the DNR
responded. It turns out the likely culprit is the larch casebearer, a
non-native small caterpillar originating in Europe that was accidentally
introduced to the US in 1886. Their natural history cycle begins with the adult
moth mating and laying eggs in June and early July. Tiny caterpillars emerge
about two weeks later, bore into the tamarack needles, and feed within the
needle. Though tamaracks drop their needles in late October, the caterpillar is
able to overwinter and resume feeding on the new needle growth in the spring.
The caterpillars hollow out the inside of the needles, and then carry the
needles around as a makeshift home, hence the name “casebearer.” The needles
turn brown, giving the trees a tan/brown appearance. The caterpillars then pupate
in May, emerge soon as adults, and start their life cycle over again.
The good news is that tamaracks can
withstand multiple years of defoliation, so the tamaracks often survive.
However, some also succumb if they are weakened enough to make them susceptible
to attack by the native Eastern larch beetle. Trees being killed by
Eastern
larch beetle turn bright yellow
starting in August and often have lots of sap
flowing down the trunk from
multiple beetle attacks. In the winter,
woodpeckers
often seek out the infested
trees and remove much of the bark as they search
for the beetles, leaving the main stem of the tree a rich red color.
Celestial Events
Three
planets are currently visible in the night sky: Mars glows in the southwest,
shining at a magnitude around 0.0. On 7/13, it will pass very close to the star
Spica, just to its north. Saturn is also still visible in the early evening
sky. It shines at magnitude +0.3, and remains a good telescopic object, its
ring system tilted towards us at an angle of approximately 20 degrees. Venus continues
as a morning star, rising about two hours before the sun in the northeast.
July’s
full moon occurs on the 12th. It’s known variously as the “Full Buck
Moon” for when the new antlers of buck deer appear, the “Full Thunder Moon”
because of the frequency of thunderstorms in July, and the “Hay Moon” for the
first cutting of hay in farming localities. The Ojibwe called it aabita-niibino-giizis, or the “Raspberry Moon.”
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