[Maine-birds] Brown Pelican -- eBird and age

Thank you,

To everyone entering their sightings of Maine's first definitively documented Brown Pelican into eBird. And thanks for the terrific and detailed write-ups (Doug Hitchcox, for example—https://ebird.org/ebird/view/checklist/S37719895) and photographs (http://tinyurl.com/yau7rggl). This is also a bird that should be reported to the Maine Bird Records Committee. One's eBird report is good for that, but if anyone had more photos or information to send us, here is the link for doing that: https://sites.google.com/site/mainebirdrecordscommittee/rare-bird-report-form

This part is for eBird users:
Although eBird offers many subspecies categories, unless one can identify a bird to subspecies (or subspecies group), as one might to species, it is best to leave the category entered as the most general, species-level taxon. There some "safe" bets for subspecies use, but even most of those are based on probability and are better avoided unless actual identification criteria are noted. For the Brown Pelican currently in Maine, one should use "Brown Pelican" without any subspecies group descriptors. This is to avoid presuming identification only on the grounds of geographic probability, which is circular reasoning. Their are options, but let's allow evidence to guide us. Immature birds don't offer much to go on for subspecies in Brown Pelican.

This is about the age:
This bird is well beyond its juvenile stage (juvenile plumage). People often use the word juvenile as a synonym of immature, and that's okay but ambiguous when describing a bird's age or plumage. Using immature is preferred unless specifically meaning juvenile plumage. Happily, most observers are using the terms correctly.

I said yesterday that it was a "first-year," but the bird is definitely older than that. It is showing wing molt, with new inner primaries and some replaced secondaries, as well as some white feathers in the head and the side of the neck bordering the gular pouch. At a distance, the bird looks more or less plain brown above, but it does show a more variegated pattern in closer views, with some pointy and silvery-bordered wing and back coverts typical of immature birds at an older age. Lastly, I noticed yesterday that the bird is showing a pale, whitish stripe on the ventral side of the bill pouch. That too is something seen on older birds in their second 12 months of life, i.e. 13-24 months old and probably closer to the 20 month range. The whitish belly and the whitish stripe on the underwing combined with the pale brown upper parts are shared by all immature Brown Pelicans, which gradually become all dark on the belly and underwing like adults at about three years of age and beyond.

These pelicans don't leave the nest until their first flights, which typically happens about 3 months after hatching. Big bodies to grow into, gangliness, etc. = long-time growing up. Their fishing ability and proficiency at diving is likewise slow to mature and takes years. And why do pelicans incubate eggs with their feet? Come on! When DDT was implicated in egg-shell thinning, those clumsy, big, totipalmate feet and that incubation method meant a lot of broken eggs. When I started birding in the late 1960s, this species was at a low point, though still fairly common in southern California then. Brown Pelicans have increased tremendously since with banning of those pesticides and better management of fisheries (anchovies in the California case). At least in the North Pacific, Brown Pelican populations historically advanced and retreated with warmer (advance) and cooler (retreat) ocean temperature regimes that sometimes lasted several decades. Vagrant birds mean more than a tick on one's list when put in context. It could mean the regionally proximate birds are moving north, or it could indicate desperate dispersal by a more distant population. That is where determining subspecies, if we can, is valuable.

Thanks again to Lucy LaCasse for alerting us all. What a delight to see this bird!

Louis Bevier
Fairfield


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