Date: 2/9/18 12:18 pm
From: Robert O'Brien <baro...>
Subject: [obol] More (detailed) Crossbill Info and Questions
I hadn't decided whether to post all the stuff below, given the possible
waning interest in the Oregon *Crossbills of the Century* invasion,
starting late last year. (only 17+ years so far though). But with
yesterday's great observations and photos by Philip Kline (
https://ebird.org/view/checklist/S42595651 ) I'll go ahead.

There are a couple interesting images on the attached jpg that is scanned
from hardcopies of the AOU's life histories Birds of North America (1996).
1. Note the two perched species are on exactly the same twig in these 2
separate accounts. Look familiar?
2. WW Crossbill is reported to have had a breeding outpost in the Cascades!
3. Check out the Oregon Breeding Bird Atlas to the right.

So, I contacted the author of the WW Crossbill life history. He was likely
a grad student at the time of his original observations (1996) in the
Cascades.
1996 was awhile ago and he has been Distinguished Chair in Ecology,
University of Wyoming, for quite awhile now ( http://www.uwyo.edu/benkman/
people.html ) . So, it's not surprising that in short order he sent me his
notes from 29 years ago about this WW Crossbill 'colony'.

*I saw the white-wings on 23-25 July 1989 in the Cultus Lake area,
Deschutes NF. There were 15-20 of them doing a lot of singing and giving
flight songs indicative that they were about to nest. They were especially
common in an area of mature Engelmann spruce that was producing a large
cone crop. I got the impression that they had recently arrived and over the
time I was there they seemed to increase. Although I didn’t see nest
building, based on a fair amount of time observing breeding white-wings
(between 1982 and the spring of 1989) I am virtually certain they would
soon be building nests.*

He has continued to publish many articles on crossbills.

His unrelated observations were not picked up in the fabulous Oregon
Breeding Bird Atlas (Paul Adamus, primary author) of about the same
period. The atlas map suggests possible breeding though in the NE Oregon
Mtns based upon the few suggestive observations.

So, this is ancient history, what does it mean today?

1. Crossbills are known to breed wherever they find themselves, any month
of the year, given an adequate local food supply. (For instance, his
Cascades observations and some in the BB Atlas). But, year-round breeding
only occurs south of us. More northern breeding seems to be dependent upon
day-length: greater than 10.5 hours. This will occur in about a week.

2. And, it's not just WW Crossbills. We have had several Red Crossbill *call
variants* this winter. Farther south (Arizona) there have been 2 or 3 or
more call variants in the same
flying flock. Like Dave Lauten, I've always put these variants on the back
burner and been rather skeptical, but I now have to admit 'it's for real'.
And it isn't a recent observation/theory. But, will these variants return
to some ancestral breeding location, or will they breed in Oregon?

This is a once in a lifetime (Crossbill lifetime, that is) chance to find
out. So, I'd encourage OBOLers (like Philip Kline) to continue to monitor
coastal (or valley) crossbills for breeding. This is not an easy thing to
do for WWs, given the reports in the Oregon BB Atlas, *and recording their
calls would be imperative. *Doug Robinson has posted that he will be
willing to identify recorded calls of Crossbills (Red or WW), so that makes
it much easier. *Send them to Doug.* As Doug says, even cellphone
recordings will work. And, if some OBOL birders can find a breeding
colony, even if it's the local coast variant, it would be very interesting.
Could there be a misplaced call variant in the breeding colony? That would
introduce a fly into the ointment, for sure.

Bob OBrien Carver OR (where I have only seen/heard crossbills once in
many decades, and then just for an hour or so in late-summer, mature, loud,
cone-popping Austrian Black Pines. They must
not have liked this local abundance since they moved on, much to my dismay.

 
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