Flamingo Color
On my last two sightings of the flamingo, I had the impression that the bird was more richly colored than it had been previously. I mentioned this to a couple of other birders, and they thought the same. It may just be a matter of lighting conditions, but it led me to do a bit of research in Steve N.G. Howell’s Molt in North American Birds (read it and weep).
First, molt sequence in flamingos is not well understood, but it has been suggested that the birds color up a bit prior to breeding season. I’m not sure when flamingos breed, but it seems reasonable that now is “prior to breeding season” (and who knows with our confused bird).. Since nobody seems to know molt sequence, some have suggested that the pre-breeding coloration is derived from preening and substances in the preen glands. The problem is that all preen glands that have been studied produce yellow, not red or pink pigments. But, our bird seems to have taken on a bit of salmon or orangey richness, so maybe yellow added to pink makes sense. Flamingos also take several years to reach sexual maturity, so perhaps in its first year here the SMNWR flamingo was in adult plumage, but not fully mature, and is now hitting its stride.
The pink comes from carotenoids in the flamingo’s diet: eliminate them during molt while feathers are developing and you have a pale or white flamingo. Bill Pranty, in the Nat Geo Complete Birds of North America states that flamingos were largely spared from the millinery trade because their feathers faded rapidly after plucking. I interpreted this to mean, incorrectly, that a continuous feed of carotenoid compounds was required to keep the feathers pink. I repeated my interpretation to others and now withdraw it based on what Howell has to say. Howell states that pigments are taken up by feathers only as they are developing; once fully formed, pigment uptake ceases (he provides good supporting evidence of this with other species). Howell does indicate the feathers fade with time (just like everything else), whether on the bird or not.
Flamingo Movement Pattern 2/12
The flamingo flew out of the fog from the north end of East River Pool and south into the fog on SB #1 at 10:35 today. I also noted that the bird was reported on the east end of SB #2 on 2/10 (and I saw it there mid-day yesterday). So, maybe, there's an emerging pattern here (it seems to change every few days, so take it with salt): ERP early and SB #2 later. This pattern has occurred before, so maybe it will settle in or go back to random wanderings tomorrow.
Matt