Migration Research Foundation - McGill Bird Observatory

McGILL BIRD OBSERVATORY

ODDITIES

Banding offers us a rare opportunity to take a close look at some of the oddities of the bird world. Abnormal pigmentation, deformities, irregular moulting, and even hybrids are under normal circumstances difficult to spot and describe, but having birds in the hand allows us to document their occurrence and investigate the causes behind them. On this page we feature photos of some of these 'odd birds', along with commentary on some. We welcome your input - please e-mail us (oddities@migrationresearch.org) if you have similar experiences or any comments to share.

Abnormal pigmentation:

Yellow-rumped Warbler with unusually extensive yellow plumage (McGill Bird Observatory, Quebec - September 2010)

Photo by Simon Duval, September 2010 - click here for additional photos

Black-capped Chickadee with brown/faded wing feathers (McGill Bird Observatory, Quebec - October 2010)

Photo by Marcel Gahbauer, October 2010 - click here for additional photos.

Leucistic American Robin (McGill Bird Observatory, Quebec - October 2004)

Photo by Marcel Gahbauer, September 2004

Leucistic hatch-year Common Grackle (Markham, Ontario - July 2008)
Aside from the obvious patches of white feathers, there is a second oddity of note with this bird, namely the very small minority of brownish juvenile feathers that appear to have been replaced with blackish adult feathers.

Photos by Peter Bache, July 2008

Hatch-year Baltimore Orioles with red pigmentation (McGill Bird Observatory, Quebec - August 2006)

Photo by Seabrooke Leckie, August 2006

Yellow-shafted Flicker with pinkish primaries at Pointe-aux-Prairies QC, June 2005
Where the ranges of Yellow-shafted and Red-shafted Flicker overlap in western Norther America, intergrades occur that have uniformly orange feather shafts. The bird in the photos below is a Yellow-shafted Flicker, but with unusually pink-shafted feathers on both wings and the tail. Note the three distinctly pink-shafted primaries in the first two photos below, contrasting with the remainder of the yellow-shafted flight feathers; this pattern was symmetrical. The third photo shows the tail, with the shaft of r2 on both sides slightly more pink than the adjacent feathers (the contrast doesn't show up on camera as well as it did in the field - and is clearly less obvious than that of the wing, visible in the background of the same photo). This atypical colouration may be related to diet at the time these feathers were being moulted - any further thoughts on this or examples of similar patterns in flickers are welcome (oddities@migrationresearch.org).

Photos by Gilles Burelle, June 2005

Hatch-year male American Redstart with unusually orange pigmentation (McGill Bird Observatory, Quebec - August 2006)

Photo by Seabrooke Leckie, August 2006

Swamp Sparrow with irregular white rectrices (McGill Bird Observatory, Quebec - September 2005)

Photo by Marcel Gahbauer, September 2005

Female House Sparrow with a single white primary covert (McGill Bird Observatory, Quebec - April 2006)

Photo by Marcel Gahbauer, April 2006

Ovenbird with irregular white alula and primary covert (McGill Bird Observatory, Quebec - September 2007)

Photo by Marie-Anne Hudson, September 2007

Common Redpoll with orange cap (McGill Bird Observatory, Quebec - March 2006)

Photo by Marcel Gahbauer, March 2006

Lincoln's Sparrow with white toenails (McGill Bird Observatory, Quebec - September 2006)

Photo by Seabrooke Leckie, September 2006

Gray Catbird with white toenails (McGill Bird Observatory, Quebec - September 2006)

Photo by Seabrooke Leckie, September 2006

Deformities:

White-throated Sparrows with unusually short/long mandibles (McGill Bird Observatory, Quebec)

Photo by Marcel Gahbauer, April 2006

Photo by Seabrooke Leckie, September 2006

Brown Creeper with broken tip of upper mandible (McGill Bird Observatory, Quebec - September 2005)

Photo by Marcel Gahbauer, September 2005

Common Yellowthroat with crossed mandibles (McGill Bird Observatory, Quebec - September 2006)

Photo by Seabrooke Leckie, September 2006

Black-capped Chickadee with crossed mandibles (McGill Bird Observatory, Quebec - September 2005)

Photo by Marcel Gahbauer, September 2005

Swainson's Hawk with extra toes and talons (Saskatchewan - July 2009)

The two photos below were sent to us by Dan Zazalenchuk, who banded it and a sibling as nestlings. He noted that while the other young hawk appeared normal, this one had trouble standing on its left leg, as the double-taloned toe kept folding under, though one week later it was standing and making short flights. We would be interested in hearing (and sharing photos) of any similar instances. Please e-mail us at mbo@migrationresearch.org

Photos by Dan Zazalenchuk, July 2009

Tree Swallow with crossed bill (Hamilton, Ontario - May 2006)

Photos by Marcel Gahbauer, May 2006

Irregular moulting:

Hatch-year Song Sparrow replacing primary coverts (McGill Bird Observatory, Montreal QC, August 2006)
This Song Sparrow was banded earlier in August and was distinctly in juvenile plumage at the time. Upon recapture on August 25, it was seen to be replacing its primary coverts sequentially, along with the corresponding primaries. Such a pattern of feather replacement was believed to occur only during second and subsequent prebasic moults, but as this bird has shown, there is still a lot to be learned about even the most common species.

(Photo by Seabrooke Leckie)

Hatch-year Common Yellowthroat with some rectrices replaced (McGill Bird Observatory, Quebec - August 2006)

Photo by Seabrooke Leckie, August 2006

Hatch-year White-throated Sparrow with rectrix being replaced (McGill Bird Observatory, Quebec - September 2006)

Photo by Seabrooke Leckie, August 2006

Hybrids:

Apparent Slate-colored Junco x White-throated Sparrow (McGill Bird Observatory, Quebec - October 2010)

Photo by Simon Duval, October 2010 - click here for more photos

Apparent Slate-colored Junco x (White-throated?) Sparrow (McGill Bird Observatory, Quebec - October 2010)

Photo by Marcel Gahbauer, October 2010 - click here for additional photos

Possible hybrid chickadee (Inglewood Bird Sanctuary, Calgary AB, July 2007)
This peculiar-looking chickadee appears to be a resident at the Inglewood Bird Sanctuary in Calgary, first caught during banding activities in July 2007, and recaptured at least twice more in August and September. It was speculated to be a hybrid between a Black-capped Chickadee and either Boreal or Chestnut-backed Chickadee. However, the patchy appearance of brown feathers suggests they may just be a plumage abnormality. Any thoughts about the identity of this bird are welcome (oddities@migrationresearch.org).

Photos by Shonna McLeod, July 2007