White bird chase in Newfoundland, The Osprey, Spring 2015, 46 (2): 13-17

[lancy cheng]

With the great help from our birding community, an article about colour aberrations in birds, written by Ms. Andrea Dicks and yours truly, has been publish in The Osprey (http://naturenl.ca/osprey):
https://www.flickr.com/photos/93331440@N08/21276890163/in/dateposted-public/

Here, I'd like to repeat what we have said in the acknowledgements:
"We thank Mr. Hein van Grouw of the Natural History Museum (London, UK) for his kind help in identification of colour aberrations. We thank Anthony L. Lang, Carol A. Sparkes, Judith Blakeley, Melanie Whalen, Bruce Rodrigues and Darroch Whitaker for providing photos and information of sightings". And, we thank everyone for your kindness and attention!

To sum up what has been talked about in this article, I will briefly explain the types of colour aberration of each bird we have referred. Some of the birds we are all familiar with but some have never shown to the public. I would appreciate if the owners would post links of your photos or authorize me to do so (you have all right reserved, for sure).

Key information: there are 2 type of melanins:
(1)eumelanin: for black and similar colours
(2)phaeomelanin: for brown and similar colours

Birds of interest:
1. Black-legged Kittiwake, ino, Anthony L. Lang. It was the best candidate for Albinism but turned out to be another mutation, ino, a result of qualitative reduction of both melanins. Some residue of brownish colour can be seen in this bird.
2. Black-capped Chickadee, progressive greying: The chickadee of Kent's pond, "Poppy", had been gone viral for a while. He was, however, not leucistic as once we thought. This type of colour aberration is called progressive greying, a result of mostly non-genetic reasons, e.g. food, disease, aging. This is the most common form of colour aberrations, which means, if you saw a white bird in a examination, to chose "progressive greying" would give you the best chance to score :P
3. Evening Grosbeak, progressive greying, Carol A. Sparkes. Progressive greying could be difficult to tell from leucistic. One field mark of leucism is all white patches are bilateral symmetric. I got a good candidate of leucistic crow while waiting for the Baird's Sandpiper in Virginia lake. It didn't look astonishing.
4. American Goldfinch, brown. This is the ghost finch in Bowring park, who accompanied Pippin, the pine warbler. SHE and the redish Tufted duck, in town year back, are both "brown", due to the qualitative reduction of eumelanin (phaeomelanin normal, so, "brown"). Most brown birds are female. Brown is the second most common colour aberration next to progressive greying.
5. Tufted Duck, brown, Judith Blakeley
6. Northern Goshawk, mount, leucistic, Melanie Whalen. This was a true Leucistic bird, all characteristics checked.

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LC

[Tony L.]

Lancy:
I think your article must be in issue 3 (Fall?). I downloaded issue 2 a few weeks ago and the article isn't in that issue.
- Tony Lang

[lancy cheng]

Hi Tony,
The manuscript shows 46 (2) spring 2015. They will probably changed it. For now, it's not the final version yet but "a proof for you (me) to edit". I guess it won't be able to catch the Spring Subway.
Lancy

[Tony L.]

Nature NL just announced the publication of issue number 3 of volume 46 of The Osprey (pages 13 to 17). That issue has Lancy's and Andrea's interesting article on colour aberrations in birds. I learned quite a bit from the article.

[lancy cheng]

Thank you, Tony, for the information and for your great photos! :)
Lancy