Shai distilled down some common-sensical aspect of the complications surrounding Iceland Gulls and what our perceptions are about how solid these are as a taxon. As an exiled Brit, I grew up on nominate glaucoides Iceland Gull and it often involved searching through these for a vagrant kumlieni "Kumlien's" Iceland Gull. It is more a continuing bad-habit that I refer to them as Kumlien's Gull here since, as Shai points out, there really isn't that much of a need for separating them to sub-species level in the US, as perhaps there is in Europe where kumlieni shows up more regularly.
Interestingly, adult iceland Gulls were scarce here in New England compared to the numbers of first-cycle birds so it was always cool to see an adult. The ones I have seen here in CT have all been mid-grey – to pale grey pigmented and black-primaried individuals seem rather uncommon at this latitude. Not sure that as quantitative evidence it amounts to anything from a scientific aspect but I wonder what drives the range of pigmentation in these birds…hormones, geography, actual hybridization? There seems to be a lot of talk – confusion – is perhaps more apt about what these birds are based on perpetuated myths about "hybrid swarms "of kumlieni or interbreeding populations of kumlieni x thayeri etc and as Shai points out it may not benefit us, in lieu of quantitative and qualitative scientific study, to continue thinking that black-primaries Iceland Gulls here in the US have "x" amounts of thayeri genes flowing through them and more whiter-primaried birds have perhaps a more glaucoides influence. As for separating adults from nominate glaucoides Iceland Gulls from Northern Europe, certain birds in Newfoundland seem to check the right boxes so with care the odd bird might be identifiable by sharp observers. Intrestingly, the long-calls of these white-winged gulls was recently studied and written up by Belgium birder Peter Adriaens here: http://birdingfrontiers.com/2014/01/09/calls-of-thayers-kumliens-and-iceland-gulls/ Good birding, Julian Julian Hough New Haven, CT 06519 www.naturescapeimages.wordpress.com -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME http://www.NortheastBirding.com/NYSbirdsRULES http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/[email protected]/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birdingonthe.net/mailinglists/NYSB.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
