Topics

Gull


Bob Chapman
 

Yesterday I came upon a gull that was a head scratcher. Superficially aligned with California Gull but not quite right; larger, lighter mantle (approaching Herring Gull), bill larger with the gondyle angle more severe. After input from several folks I believe it to be L c. albertaensis, the Northern Great Plains subspecies. I don't have any experience with this race so let me know if you do.

The first Black-vented Shearwater showed up yesterday in South Oso Flaco and today I have seen several more.

Elegant Terns are MIA at OD this summer but today there are a couple dozen present.

Bob Chapman
Oceano Dunes



Alvaro Jaramillo
 

Bob

   The interior and northern albertaensis California Gull is theoretically common on the West Coast during the non-breeding season based on banding evidence. The issue is that most individuals are not field separable from the nominate California Gull. On average, albertaensis is larger and paler. The size is perhaps the most reliable feature. Some individuals stand out in flocks in coastal California, but my guess is that the large majority of albertaensis are stealth migrants, totally undetected and undetectable. No clear evidence of wing pattern features exist, but some have thought that albertaensis may be more likely to have an entirely white tip to P10. Maybe, maybe not.

Alvaro

 

Alvaro Jaramillo

alvaro@...

www.alvarosadventures.com

 

From: slocobirding@groups.io <slocobirding@groups.io> On Behalf Of Bob Chapman via groups.io
Sent: Thursday, July 30, 2020 1:01 PM
To: Slocobirding <slocobirding@groups.io>
Subject: [slocobirding] Gull

 

Yesterday I came upon a gull that was a head scratcher. Superficially aligned with California Gull but not quite right; larger, lighter mantle (approaching Herring Gull), bill larger with the gondyle angle more severe. After input from several folks I believe it to be L c. albertaensis, the Northern Great Plains subspecies. I don't have any experience with this race so let me know if you do.

 

The first Black-vented Shearwater showed up yesterday in South Oso Flaco and today I have seen several more.

 

Elegant Terns are MIA at OD this summer but today there are a couple dozen present.

Bob Chapman

Oceano Dunes