Subject: Re: Red Crossbills
Date: Jun 23 07:56:56 1997
From: Mike Patterson - mpatters at orednet.org




>

> pines, whereas White-winged generally specialize on the smaller-seeded
> spruces, etc. We have good numbers of each this year here in c. BC.
> >>
>Thanks for the info. I have 4 pine trees in my yard. Of course, that's not
>where I saw the crossbills, they were pigging out in my feeder! :-)
>

I feel obliged to respond to this idea that Red Crossbills are "big seed"
eaters. There are currently no fewer than 8 distinct Red Crossbill types
in North America. Of these, 6 have turned up in the Pacific Northwest.

"Type 3" Red Crossbills most regularly forage in small coned coastal spruces,
hemlock and Douglas-fir. This type averages smaller overal and has a smaller
bill. "Type 2" and "Type 7" are more frequently encountered in the eastern
parts of Oregon and Washington where they are associated with pines. They
average larger and so do their bills.

Some people suggest that there are enough differences to separate these
types into species. This may be justified for "Type 6" which is found in
Arizona and Mexico an is, by all accounts, huge. It also shows good
discriminants in all useful measurements for separation.

As to White-winged Crossbill, they tend to be apline or subalpine. Their
food preference leans toward true fir cones and they do go for smaller sized
cone bearing trees, but they are not substatially different in foraging
strategy than "type 3" Red Crossbills. I have seen "type 3" Red Crossbills
and White-winged Crossbills in the same Silver Fir in the Central Oregon
Cascades.



--
*********************************** I got the blues so bad one time
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