English and Scientific names:

California Gull, Larus californicus

Number of individuals: 

1 in 1st  basic [first winter] plumage

Locality: LOUISIANA: 

Vermilion Parish

 

Specific Locality:

Intersection of Highways 167 and 696 south of Maurice.

 

Date(s) when observed:

December 31, 2005 and January 1, 2006

 

 

Time(s) of day when observed:  

Late morning or mid-day

Reporting observer and address:

Paul Conover

Lafayette, LA

 

 

Other observers accompanying reporter who also identified the bird(s):

 

Light conditions (position of bird in relation to shade and to direction and amount of light):

On both days, patchy morning fog persisted from the night before. Light varied from foggy and bright to full sun. Sun was to south, bird to northeast.  

Optical equipment: 

Zeiss 10x40’s, Kowa TSN w/ 20-60 zoom

 

Distance to bird(s): 

70-100 yds.

Duration of observation:

About 1 hour on 12/31/05, and about 15 minutes on 01/31/2006.

Habitat: 

Plowed muddy field.

 

 

Behavior of bird: 

The bird was first observed resting alongside an adult Herring, among a flock of a few hundred Ring-billed and Herring Gulls, a few Laughing Gulls, and one Lesser Black-backed Gull.

 

Description:

This bird was striking in the amount of contrast it presented. The light parts were bright, the dark parts very dusky. It was a very strikingly patterned bird compared to the 1st and 2nd year Herrings.

v    Bird intermediate in size between the majority of the Herrings present and the Ring-billed. I would say the bird was slightly smaller even than the runt Herrings.

v    The head was definitely smaller relative to the overall size of the bird than in the Herrings, and was noticeably rounder. The bill was thin.

v    Head: The front of the head was overall strikingly light, white or very nearly so. This white contrasted strongly with the dusky auriculars. The bird had either whitish crescents or eyelids that stood out even at a great distance against the duskiness of the auriculars. Forecrown was very white, blending into sparse streaking at midcrown, roughly even with the front of the eye. The streaking grew denser on the nape. The malar area, chin and throat were white. The overall effect was of a masked bird.

v    The body was darker than the head, although some white areas continued down the breast of the bird from the throat. This white area stopped at about the belly. The belly was a smudgy or streaky brownish.

v    The mantle was fairly dark, with dark brown, and dusky overtones, and a few newer, dark-centered pale-edged feathers coming in. There was also an unusual rusty tone present, especially on the very deeply- marked hindneck.

v    The lesser coverts shared the tone of the mantle.

v    The median coverts were colored like the lesser coverts, edged paler.

v    The greater coverts were much darker than the lesser and median coverts, and paler than the secondaries. They were apparently solidly dark from the bases to about ¾ of the way distally, at which point paler mottling became noticeable upon close observation. The paleness became pronounced on the distal edges.

v    The primaries and secondaries appeared dark brown. Primaries extending well beyond tertials and tail tip.

v    The tertials were dark brown, and appeared to have broad whitish/mottled tips.

v    Altogether, the folded wings appeared brownish, with whitish “wingbars” setting off contrastingly darker greater coverts, and even darker flight feathers.

v    No details of the rump, tail, or undertail were seen.

v    Soft parts: Eyes dark brown. Legs distinctly pink. Bill the same vivid pink as the legs, with a distinctly demarcated dark tip extending farther posteriorly on the lower mandible. The color of the bill and legs as they looked in the field is best seen in the digital photographs. There was also a thin dark line running parallel to the cutting edge of the bill anterior of the naris on each side, midway between the culmen and the cutting edge—basically on the same line as the nares.  

 

Voice:

No voice was heard.

Similar species:

Herring gulls in first and second year. Neither the fine pink bill with distinct dark tip, nor the dark greater coverts contrasting markedly with the median coverts [and with the even darker secondaries creating a double dark bar] are typical of Herring. The overall shape of this bird, with a relatively small, round head, is completely unlike normal or runt Herrings.  

Photographs or tape recordings obtained?

Digital photos and video stills. Together these portray the size, shape, and overall coloration and contrast of the bird.  

 

Previous experience with this species: 

Fair. Hundreds seen out west; seen previously in Louisiana.  

 

Identification aids:

 

This description is written from: 

After observation and from study of images.

Are you positive of your identification? If not, explain: 

 

Yes.

Reporter: 

Paul Conover

Date and time: 

January 7, 2004.