Thursday, September 3, 2009

Accessories make the outfit

Margie knew this beautiful, unusual bird on the beach was some sort of Laughing Gull, but the orange legs and bill are not typical, so she sent the pic off to Phyllis, who sent it on to an expert, who came back with this explanation: It is an adult Laughing Gull in basic plumage, but with aberrant soft-parts' colors. Every so often a Laughing Gull shows up with an orange bill, legs and feet. They are probably more prevalent in the Gulf because there are more breeding colonies and more Laughing Gulls there than along our Atlantic coast. Laughing Gulls normally have a red mouth-lining when they breed, so they likely have carotene underlying the melanin of the normally dark legs, feet and bill. When the melanin pigment is absent, probably due to a genetics anomaly, it exposes the underlying color that appears as orange rather than red, because red is usually the result of increased vascularization during the breeding season; this bird, as are most found, is not in breeding condition. (Thanks to Bruce Anderson, amongst other things the Regional Coeditor, Florida Region, "North American Birds", for this great explanation.)

This photo by Jim Angy shows a more typical Laughing Gull in summer plumage (in the winter, the head is frequently grey-white).
About a year ago, Margie sent a photo that allowed me to use the term "many ribbed hydromedusa" in a sentence. We will add "aberrant soft parts" to the list of things you don't often get to say, although in thinking about it, this new term might well work its way into a conversation :) Meanwhile, we'll continue to think of Margie's Laughing Gull as a tricked-out chick with great accessories.

1 comment:

Cactus Jack Splash said...

Lovely photos. I like how the last one reflects the bird in the water