Michael, we did add cormorants to that earlybird list after my original post. The molt is just a lot more dramatic in alcids, at least in guillemots and murres, as it brings on a substantial change in plumage color. In all three regional cormorants, the only visible sign of it are breeding plumes and bare-skin color, not so obvious except at close range but indeed very dramatic then.

This isn't the first time I have wished I could add photos to a post! ;-)

Dennis Paulson
Seattle


> On Feb 6, 2023, at 11:55 PM, Michael Price <loblollyboy at gmail.com> wrote:

>

> 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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