April 1st, 2012, 03:27 AM
Winter Asymmetrical Multi Loci Secondary Molt - 3cy Lesser Black-backed Gull
I do not chase all birds but usually choose a few species and spend a lot f time with them. This winter I did even something more ‘crazy’ and I also spent a lot of time chasing just one bird. 3cy (second winter) LBBG (from early January to March; then lost it). Why? - Because at that time this gull was molting secondaries (not only this one but I did not have time to work on more photos, not yet) in what I think atypical time of the year. Correct me if I am wrong about it but all available to me published studies show that this is not a typical time for this age LBBG to molt primaries/secondaries and most other LBBG of the same age that I observed at the same time didn’t. Also molt progress was interesting as well – it was asymmetrical (time of shedding and growing secondary feathers in both wings was different) and was starting in multi loci. But I think the documentary photos illustrating this progress will show more information that any lengthy description I could write. I did not include photos illustrating the primary, tail, wing covert molts and bill coloration as this task will take me to much time to put together at this moment. I would like first to find out if this case is interesting to pursue so informed comments are welcome. I could also study images of couple more 3cy LBBG that were molting in similar way but were in different stage (for example starting secondary molt) to fill some gaps (these were only single encounters). Anyway it seems (judging on many second winter LBBG I observed this winter) that secondary molt at this time of the year (here on Upper Texas Coast) is rare but asymmetrical multi loci molt occurs in most if not all cases of molting individuals (probably with no preference which wing starts to molt first). BTW I liked the challenge of not only trying to find this gull as many times as possible during two month period but also with many tries to get usable photos of both wings. Light and wind direction were not always on my side. Most likely I lost this gull because for several weeks now it seems to be much less available food resources (another interesting subject) and beaches became overcrowded with people.
Again some informed comments could help me to decide if I should to peruse checking thousands of photos or not - I will appreciate any help and suggestions/corrections.
Here is a link to composite photo that is showing molt progress in 57 days:
(original file is huge so I hope compression did not destroy too many details)