[Tweeters] Pigeon Guillemot in Breeding Plumage in Early February?

[Michael Price]

Dennis Paulson writes: <Alcids are the only group among our birds that may
molt into breeding plumage very early in spring, i.e., mid- to late
winter....>

With greatest respect, Dennis, not the only group. In the mid-90s, I did
personal-interest surveys around the Stanley Park seawall on (weather and
work permitting) a daily basis for several years. Of the Pelagic Cormorant
(PECO) wintering population at Prospect Point usually numbering about 50-60
birds, about a third would disappear in late November, only to reappear
(same birds? if so, average return date over a three year stretch, Jan 19)
in full Alternate/Breeding plumage. No idea where they went to complete
their pre-alternate molt; but it can't have been far. Because there's no
visible sexual dimorphism in PECO, there was no way to tell what age/sex
ratios there might have been in that absconding third, and I'm still kinda
unsure whether to whether call the returning birds actual migrants.

This molt-timing mirrors that of West Coast alcids, and I wouldn't be
surprised if it applies to Brandt's Cormorant (BRCO) as well. Would it
apply to Double-crested Cormorant (DCCO) (which, god help me, is still
think of an eastern species come west) too?

best, m
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