Disclaimer: this is a bit gruesome.
I have witnessed Black-billed Magpie cunning and savagery in the past on my
1 acre lot in Teller County at 8,500'. A few years back, while working in my
home office, I was alerted to an awful ruckus outside in late spring. When I
went to investigate, I had found that a couple magpies had located a
cottontail nest (small depression in ground dug by the doe) and were pulling
the young (not newborns, but perhaps a third the size of an adult) from the
nest. They would either taken them a few meters away or deal with them just
a few feet away; and would then peck at them until they were either dead or
incapacitated (I really couldn't tell which); all the while carrying on an
excited frenzy of magpie calls with each other. They would then pluck the
fur, and partially eat/taste the victim. They were not satisfied with just
pulling one out and eating it. But, they pulled more than a couple out and
dispatched them all in this way.
Since January this year, I have had the joy of watching and listening to
several dozen Evening Grosbeaks (EVGR) at my feeders. They seem to come and
go over the years; mostly present in winter, and usually dispersed to
breeding sites by this time in late spring/early summer. I have never had
them around during breeding to my knowledge; but I quickly notice when they
show back up with fledged young that they are feeding in July. This year is
the exception! Beautiful male courtship dances with wings spread out wide,
head thrown back and tail stuck up in the air. Male feeding prospective
mates; mate guarding and all have been my privilege to get to watch this
year. I believe about 2 dozen are nesting in the douglas-firs in and around
my house this year, though I have not found a nest yet.
This morning while filling my feeders, I found the plucked feathers of a
male evening grosbeak. No body and not much blood on the feathers; just what
looked like a complete set of plucked body feathers. I wondered what might
have caught this sick or injured bird and dispatched it. When looking out
later, I see the apparently untouched body of a dead female EVGR lying on
the ground. It was gone not too much later and I didn't notice what might
have come and got it, but assume one of the many, rather tame, foxes living
in the area that frequent my feeders, mostly to try to catch a squirrel.
Just now however, I looked out and caught the end of a brief struggle that
ended in the gruesome death of another male EVGR. This time, the culprit was
in plain view - a black-billed magpie. I didn't get to see how this started,
but this magpie was holding down the still-struggling EVGR and pecking at it
vigorously. Soon the EVGR was done. The magpie stood on it and started
plucking body feathers off quite briskly. But before done, it went to work
decapitating the hapless victim. When completed after just a few seconds of
effort, it picked up the head and flew off with it, leaving the body and
feather pile in place. Back in just a couple minutes, it continued with
feather plucking. Before completely nude, it picked up the EVGR's headless
body, flew up to a nearby branch - right in plain view, and proceeded to eat
some innards. After a few moments, it flew off with the body in its mouth.
I believe two magpies are nesting nearby - but have not located a nest. I do
remember them collecting twigs from my shrubbery earlier this spring; and
mud from the ditch after a rain/snow. So, perhaps they are feeding young of
their own with these EVGRs.
It is also possible that these EVGRs are not being incapacitated by the
magpies themselves, but that perhaps they are hitting my windows (which
happens on occasion) and the magpies are merely taking advantage of an
already dead or stunned individual. But three window strikes in 24 hours
would be very unusual. More like one or two all season is the norm for
window strikes.
This, coupled with other events I have witnessed involving other Corvids
(namely Am Crows), really makes you wonder where the boundary of
birds-of-prey is drawn.
I reported this incident with the Crows back when it happened several years
ago, but will recap here for completeness. At Manitou Lake near my house,
several dozen red-winged blackbirds nest in the cattails in the marsh at the
south end each year. One summer morning, I happened to be there just after
sunrise to witness an event that left me amazed at the intelligence,
brutality and cooperativeness of Crows. I was surprised to see about 20
crows quietly sitting along the edge of the cattail marsh in the ponderosa
pines that border it. Birds had just started to rouse and everything seemed
like a normal dawn. Then, with stunning synchronicity, the crows started
dive-bombing the many nests located in the cattails. The raucous chaos of
the crows and the response of the blackbirds broke the morning calm quickly.
The crows seemed to dive-bomb in pairs. The first dove at the nest and drew
the adult blackbird off the nest in hot pursuit to chase away the intruder.
Quickly followed by crow #2 of the pair, snatching a freshly hatched
nestling from the nest and flying away with it. This chaos lasted for
several minutes and then it was done - the crows were nowhere to be seen. It
is hard to say for sure, but in all, I would guess anywhere from 7 to 20
nestlings were snatched successfully. Many were snatched but then later
dropped by a crow when one of the parent blackbirds caught up with it. The
overall damage to the colony due to kidnapped young or those just dropped in
the water had to be significant. These Corvids showed amazing cooperation
and cunning, that I am sure to many folks is a surprise. It was to me the
first time I saw something like this.
FYI
Jeff J Jones
( <mailto:[email protected]> [email protected])
Teller County - 8500' - Montane Woodlands
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