Two species of "White-winged" Gull
at Conestogo Dam
26 December 2012
This afternoon, while enjoying an afternoon's winter birding my wife and I spotted these two gulls among the numerous American Herring Gulls Larus smithsonianus and a couple of Ring-billed Gulls Larus delawarensis.
As noted in a previous post on my blog subadult gulls are notoriously difficult to age with any degree of confidence but based on the literature I have studied I would categorize these gulls as first cycle Glaucous Gull Larus hyperboreus and first cycle Iceland Gull Larus glaucoides. Actually we located two similarly plumaged Iceland Gulls, both initially observed in the slipway area of the dam on the side opposite the lake.