[birdky] BirdKY: Crossbill info

All: 

Thought this e-mail from Marshall Iliff (Cornell Lab of Ornithology) to
the Massachusett Birding Listserve would be of interest to some of you
that have already seen, or are hoping to find, the Red Crossbills.  If
you have access to recording equipment and can record the flight call
(sometimes given while perched too), it would be interesting to see
which "type" of crossbills these are.  If somehow you get recordings,
let me know and I can put you in touch with Marshall.

E-mail below:

Subject: Red Crossbills may represent multiple species--get tape! 
From: "Marshall J. Iliff" <miliff(AT)aol.com> 
Date: 16 Nov 2007 1:42pm 
Massbird, 
With the massive finch movement afoot Massbirders should try to step up
their reporting of "Red Crossbill" to the next level. Birders are
becoming aware to differentiate Eastern Willet (T. s. semipalmata) from
Western Willet (T. s. inornata) and Atlantic Brant (B. b. hrota) from
Black Brant (B. b. nigricans), as well as other subspecies as in
Nelson's Sharp-tailed Sparrow, White-crowned Sparrow, and more. However,
the distribution and occurrence of the various Red Crossbill types
remains one of the most poorly known bird distribution questions--in
part because significant invasions have only happened once or twice
(1997-1998 was the last great year I remember) since Jeff Groth's 1993
paper (Groth, J. G. 1993.Evolutionary differentiation in morphology,
vocalizations, and allozymes among nomadic sibling species in the North
American Red Crossbill (Loxia curvirostra) complex. Univ. Calif. Publ.
Zool. 127: 1-143.) that discussed the different call types of Red
Crossbill and the fact that each call type may represent a valid
species. 
The issue is discussed in depth at:
http://research.amnh.org/ornithology/crossbills/. 
In summary, Red Crossbill is a Holarctic (New World and Old World,
northern hemisphere) species composed of up to 20 different subspecies
or groups. In North America the subspecies taxonomy has been extremely
confused, but research by Groth and others indicates that there are 8
different call types that can be distinguished by sonogram. The key call
is the flight call (also given perched), often described as
"jip-jip"...different from the softer "took" calls given while perched
and different from the song. The known distributions (roughly) are as
follows, according to Groth (1993), with the possible forms in MA marked
with asterisks (*): 
*Type 1=Widespread--can occur nationwide; some breed in central and
southern Appalachians 
*Type 2=Widespread--can occur nationwide; some breed in central and
southern Appalachians 
*Type 3=Widespread--can occur nationwide 
*Type 4=Widespread--can occur nationwide
Type 5=Widespread in West from Rocky Mountains west 
Type 6=southeast Arizona and west Mexico 
Type 7=Sierra Nevada, Cascades, and western Rockies 
Type 8=restricted to island of Newfoundland 
In the big 1997-98 flight in Maryland I helped to collect recordings of
Red Crossbill calls. We found that almost all of 20 or so recordings
involved Type IV birds, with the exception of a single bird mixed in
with one small flock which included a Type III bird. 
What does this mean for Massbirders? 
1) It is conceivable that one day, when this complex is fully
understood, North American Red Crossbills will be divided into 8 or more
species 
2) It is therefore conceivable that you will have to list "Red Crossbill
sp." on your Massachusetts list instead of the four potential species
you could have had! 
3) The best way to document and understand which forms occur in
Massachusetts is to GET AUDIO RECORDINGS OF THEIR FLIGHT CALLS. If any
Massbirders have the means and willpower to get audio recordings of Red
Crossbills this year, I'd be happy to collect the recordings and
summarize the findings at the end of the season. 
4) If anyone has audio recordings from New England from anytime in the
past, it would be worth archiving those as well. 
Best, Marshall Iliff 
PS -- No, Jeremiah Trimble and I were not responsible enough to have
recording gear at the ready with our Nahant Crossbills 8 Nov 2007. We
did try to identify them by ear and felt they were most probably "Type
IV" based on the abrupt, Empidonax like call note. The photos show
small-billed birds, more consistent with Type IV or Type III than larger
Types I or Type II. We wish we had gotten recordings though!


Happy birding....
Brian W. Smith
Certified Wildlife Biologist
Appalachian Mountains Joint Venture Coordinator
American Bird Conservancy
3761 Georgetown Road
Frankfort, KY  40601

Reply to: bsmith@xxxxxxxxxxxx or brianw.smith@xxxxxx
Phone: 502-573-0330, ext. 227
Fax: 502-573-0335
Visit: www.abcbirds.org

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