Brown Pelican Yellow Morph, with Yellow Gular Pouch (Throat) instead of Red

By December 27, 2021January 11th, 2022Pelicans, Seabird

The Yellow Variant, or Morph, of the California Brown Pelican

I have noticed quite a few brown pelicans sporting yellow gular pouches (throats). As everyone knows, the gular pouch expands to catch water and prey, as much as three times the volume of the pelican’s stomach.  Not only is the gular pouch critical to the foraging ability of the bird, but it’s coloration serves a social purpose.  In winter California brown pelicans (Pelecanus occidentalis californicus) adopt a brilliant winter breeding plumage, most notable of which is red and olive green coloration of the gular pouch.  But among the brown pelicans around here I have noticed more than a few with yellow instead of red.  What causes that color?  Are they juveniles, or non-breeding adults?  Is this simply a common trait I have not noticed before?  Is this some sort of regularly-occurring variant or morph?  Honestly, I don’t know.  And not being much of a birder or biologist I may never learn the story behind it. However, it is interesting to observe these yellow-throated brown pelicans, and cool to see both yellow and red together.  Here are a few images I have made of them recently.  The first image shows how distinctly different the red and yellow versions are.

Two California brown pelicans mock jousting, displaying vividly-colored throat skin and mating plumage, Pelecanus occidentalis, Pelecanus occidentalis californicus, La Jolla

Two California brown pelicans mock jousting, displaying vividly-colored throat skin and mating plumage.
Image ID: 36703
Species: Brown pelican, Pelecanus occidentalis, Pelecanus occidentalis californicus
Location: La Jolla, California, USA

Brown pelican preening, cleaning its feathers after foraging on the ocean, with distinctive winter breeding plumage with distinctive dark brown nape, yellow head feathers and red gular throat pouch, Pelecanus occidentalis, Pelecanus occidentalis californicus, La Jolla, California

Brown pelican preening, cleaning its feathers after foraging on the ocean, with distinctive winter breeding plumage with distinctive dark brown nape, yellow head feathers, although this one displays a yellow (rather than the usual red) gular throat pouch.
Image ID: 36683
Species: Brown pelican, Pelecanus occidentalis, Pelecanus occidentalis californicus
Location: La Jolla, California, USA

Yellow Morph California Brown Pelican Portrait, note the distinctive winter mating plumage but the unusual yellow throat, La Jolla, California

Yellow Morph California Brown Pelican Portrait, note the distinctive winter mating plumage but the unusual yellow throat, La Jolla, California.
Image ID: 37433

California Brown Pelican head throw, stretching its throat to keep it flexible and healthy, Pelecanus occidentalis, Pelecanus occidentalis californicus, La Jolla

California Brown Pelican head throw, stretching its throat to keep it flexible and healthy.
Image ID: 36692
Species: Brown pelican, Pelecanus occidentalis, Pelecanus occidentalis californicus
Location: La Jolla, California, USA

A brown pelican preening, reaching with its beak to the uropygial gland (preen gland) near the base of its tail. Preen oil from the uropygial gland is spread by the pelican's beak and back of its head to all other feathers on the pelican, helping to keep them water resistant and dry, Pelecanus occidentalis, Pelecanus occidentalis californicus, La Jolla, California

A brown pelican preening, reaching with its beak to the uropygial gland (preen gland) near the base of its tail. Preen oil from the uropygial gland is spread by the pelican's beak and back of its head to all other feathers on the pelican, helping to keep them water resistant and dry.
Image ID: 36844
Species: Brown pelican, Pelecanus occidentalis, Pelecanus occidentalis californicus
Location: La Jolla, California, USA

Yellow Morph California Brown Pelican Portrait, note the distinctive winter mating plumage but the unusual yellow throat and near-absence of yellow feathers on the head, Pelecanus occidentalis californicus, Pelecanus occidentalis, La Jolla

Yellow Morph California Brown Pelican Portrait, note the distinctive winter mating plumage but the unusual yellow throat and near-absence of yellow feathers on the head.
Image ID: 37557
Species: Brown Pelican, Pelecanus occidentalis californicus, Pelecanus occidentalis
Location: La Jolla, California, USA