Red Crossbill (type 2), Prescott Peninsula, MA, July 30, 2012 |
Red Crossbill (type 2) video, Prescott Peninsula, MA, July 30, 2012
As a follow up to my reports on Red Crossbills on the
Prescott Peninsula at Quabbin the specific type has now been determined. The specific type of Red Crossbill has been
determined to be type 2. This was
determined with the assistance of Ian Davies who converted the video, with its
associated audio, into a wave file and then used the Cornell Lab of
Ornithology’s free software (Raven Lite) which can be downloaded from this
link:
The recordings I
obtained were compared to those of the different known types of Red Crossbills
using a spectrogram. The determination
of type was obtained in this fashion. Type
2 Red Crossbills occur across a large area of the country including the
northeast. Other types have/could occur
in this area. There are at least nine (or ten) recognized types of Red
Crossbill. The overall size of the bird
and the bill varies with each type but determining all types by sight alone is
difficult to impossible. The only way
sure way to differentiate the types is through calls viewed as a spectrograph.
Additional
information concerning these various types and their associated calls can be
found at the following link:
http://ebird.org/content/ebird/news/introduction-to%20crossbill-vocalizations
As with previous
sightings of Red Crossbills in this area breeding is suspected (and has been
confirmed in the past). The first Red
Crossbills on Prescott Peninsula were noted on June 3, 2009 and small numbers
were seen through the end of the year in 2009.
The largest number seen on any one day during that year was 14. In 2010 they were first noted in April and
seen through early July. The largest
number seen on a single day in that year was 26. During the other years of the breeding bird
atlas they were not noted. Juvenile
birds with adults feeding them were noted in both 2009 and 2010. Also during 2010 they were noted in Quabbin
Park in the same area from mid October through the end of November with the
greatest number seen being 14. A great
overview of breeding in the state can be found on the Massachusetts Breeding
Bird Atlas page found at the following link:
http://massaudubonblogs.typepad.com/massbirdatlas/2010/11/218-red-crossbill.htmlTo sum up the above mentioned link the number of breeding Red Crossbills is quite small in the state with the only confirmed records during the entire five year long atlas study occurring at Quabbin, specifically on the Prescott Peninsula. The other probable location for breeding in the state was also at Quabbin, located in Quabbin Park. The only block with possible breeding was located in Plymouth County. Certainly one of the rarer breeding species in the state with only a handful of confirmed records. It does appear that the Prescott Peninsula is a breeding hotspot for this species in Massachusetts.
Red Crossbill
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Blocks
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All
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3
|
|
1
|
|
1
|
|
1
|
|
Blocks with evidence ¹
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5
|
Chart above courtesy of Mass Audubon and the Massachusetts Breeding Bird Atlas.
For a little bit more information the range maps of various types can be found at the following link:
With
the permission of the staff at Quabbin I hope to continue additional research
on this species on the Prescott Peninsula in the coming years.
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