Point La Jolla – American Oystercatcher form frazari

Posted on August 7, 2015 by Gary Nunn

[All photographs copyright, Gary Nunn 2015] – Flying in from the north, low over the ocean, a large shorebird quickly got my attention at Point La Jolla early this morning since a Western Gull was chasing right behind it. Weird! Things made more sense however as it approached closer and the large body and shallow stiff wingbeats soon added up to an incoming oystercatcher! As it came flying in I started to see the white belly which lifted my interest level much higher! I was hoping for a circle flight around below my viewpoint, for photography, but instead it bee-lined to a rocky perch right in front of me. Luckily it then decided to move a few yards, in a short flight, allowing a few upper and under wing photographs.

Referencing information given in Pyle (1997) and additional material at the website of the American Oystercatcher Working Group this individual seems, so far as I can tell, to match the description of a frazari form of American Oystercatcher Haematopus palliatus. It has a well demarcated black bib with a little black mottling at the sides, white underparts, white undertail coverts, almost complete white underwing, and a white greater secondary coverts wingbar on the upperwing. The uppertail coverts are mottled black and white, but this also seems consistent with descriptions in the reference literature.

I did make a preliminary score using the system described in the publication by Jehl (1985) on hybridization in oystercatchers in Baja California. The scoring instructions from Table 1 of this publication can be found, rather usefully, at the Western Field Ornithologists Rare Birds of California entry for American Oystercatcher. This individual scores high in the range, about a 33, and would be attributed to American Oystercatcher using this system. I had to make a guesstimate on the white wingbar width, I conservatively put it in the middle of the range but it does look pretty wide to me!

American Oystercatcher form frazari – La Jolla, San Diego County, California 07 August 2015 (© Gary Nunn)

Mew Gull in the mist – Pt. La Jolla

Posted on February 27, 2014 by Gary Nunn

[All photographs copyright, Gary Nunn 2014] – This first cycle Mew Gull Larus canus brachyrhynchus surprised me at Pt. La Jolla this afternoon when it suddenly appeared coming around the point. The misty conditions made photography problematic and I was impressed with the performance of my new Canon 1Dx camera body. The full frame sensor of the 1Dx, paired with the 500 mm f4.0 and 2X teleconverter, admirably pulled off this image acquisition at the 1000 mm effective focal length in spite of poor light and the considerable distance.

This first cycle Mew Gull has molted into some first prealternate plumage revealing newer white feathers about the flanks and chest as well as a light gray mantle. Some juvenile feathers remain, for example the brown feathers of the belly as well as the faded and mismatched looking upperwing coverts. I find the easiest way to tell this species from Ring-billed Gull, potentially confused with Mew Gull at this age and plumage, by the bill shape. Mew Gull has a thinner bill with a more shallow curvature to the culmen tip providing a more gentle looking bill. Ring-billed Gull on the other hand is deeper billed with a strongly decurved culmen tip which contributes to its more aggressive and substantial looking head morphology. The dusky underwing, particularly darkish around the axillaries, and brownish “scarf” around the neck are also characteristically good field marks for an immature Mew Gull.

Mew Gull first cycle – Pt. La Jolla, La Jolla, San Diego County, California 27 Feb 2014

Long-tailed Duck just after dawn – Pt. La Jolla

Posted on December 7, 2013 by Gary Nunn

[All photographs copyright, Gary Nunn 2013] – It was barely getting light this morning when I spotted a small white-bellied duck careening wildly along the edge of the kelp beds at Pt. La Jolla. It looked interesting so I leveled the camera on it and snagged a dozen shots as the duck pulled up and stalled to sit down on the water outside of the kelp. It was 7:01 a.m. to be exact and my Canon 7D camera sensor was having trouble capturing images at all, even at ISO 3200! From the camera back the duck appeared white collared and distinctively white bellied. It also had a dark crown and cheek patch kind of extending as a rear strap behind the face. Finally, the wings were entirely blackish both on the upper and under surface, in particular the striking dark underwing coverts were noticeable. Evidently my hoped for Long-tailed Duck Clangula hyemalis had appeared as early in the day as possible! I guess I should not complain about poor lighting for photography, birds just come by you when they want to as a rule! This is my first Long-tailed Duck of the 2013-2014 winter period. Unfortunately, given the very choppy water conditions and poor lighting, other birders were unable to relocate the stationary duck in the immediate vicinity with their field scopes.

Long-tailed Duck – adult female Pt. La Jolla, La Jolla, San Diego County, California 07 Dec 2013

Buoyed by the early morning success I waited out the seawatch a few more hours but could only add a very nice looking adult basic plumaged Mew Gull Larus canus to the list. The Mew Gull flew south around the point just a short distance from the rocks and almost escaped attention. Actually this individual appears to be in fresh looking “adultlike” plumage having completed third cycle prebasic molt with just a few black feathers in the upperwing marginal coverts and slightly reduced white tips to the outer primaries.

Mew Gull – adult basic plumage Pt. La Jolla, La Jolla, San Diego County, California 07 Dec 2013

Black Scoter female in the lead

Posted on November 21, 2013 by Gary Nunn

[All photographs copyright, Gary Nunn 2013] – I have been out testing my new Canon 500 mm f4 lens and it can really pull in excellent quality images from great distances. With the addition of the 1.4X teleconverter attached it comes out with an 1120 mm effective focal length on the 7D body “cropped” APS-C sensor size. Add to that the Image Stabilization (IS) and I think I will be documenting a few more good birds seawatching out there soon! I found this adult female Black Scoter Melanitta americana cruising at the front of a small flock of Surf Scoter heading south. As I have mentioned in previous posts on this species, it often seems to head up the front of the flock when among Surf Scoters. Perhaps the slightly smaller size allows it to travel faster than its congeners? I photographed this flock from quite an extreme distance – these ducks were just beyond the Pt. La Jolla kelp bed and can still be easily identified from the image crops.

Black Scoter adult female – Pt. La Jolla, La Jolla, San Diego County 20 Nov 2013

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Category Archives: Pt. La Jolla

Point La Jolla – American Oystercatcher form frazari

Mew Gull in the mist – Pt. La Jolla

Long-tailed Duck just after dawn – Pt. La Jolla

Black Scoter female in the lead