Photos by Len Blumin
1. Eye of the Gull
When we look at our feathered friends we see mostly,
well... feathers! Parts of birds that are bare may include the
legs and feet, bills, and facial skin. A striking feature on many
birds is a rim of unfeathered skin surrounding the eye, known as
the "orbital ring". The orbital ring is not to be confused with the "eye ring", a feathered ring around the eye that can be an important
field mark in identifying certain flycatchers, warblers, etc.
The bare parts can change in color rather dramatically when hormonal
surges occur during the breeding season. Witness the striking
transformation of the lores and sometimes legs of certain herons
and egrets. Many adult gulls exhibit bright orbital rings, which can
deepen in color in the breeding season. Here we see an adult Western
Gull (Larus occidentalis), displaying what has been described as
chrome-yellow orbital rings. Taken Nov. 7, Arrowhead Marsh, Oakland,
Wouldn't it be nice if the color of the orbital rings helped
separate otherwise similar looking white-headed gulls?
Unfortunately, according to Howell and Dunn (Gulls of the Americas),
the color of the orbital ring, and the iris itself for that matter,
can vary considerably in a given gull species. Yellow/yellow-orange
rings are seen in Herring, Western, Yellow-footed, and Glaucous
Gulls. Red or Reddish rings are found in California, Yellow-legged,
Lesser and Greater Black-backed, Ring-billed and Mew Gulls, while
the Slaty-backed shows pinkish-red and Thayer's a purplish pink.
Aren't gulls fun?
2. The Loons are Back
While doing a sea watch at Duncan's Landing, Rich S. called our attention to the southward
flight of loons taking place about .5 mile offshore. Sure enough, every 10 seconds or so a loon
would fly by, or perhaps a small group. Most were Pacific Loons, but we are seeing greater
numbers of Common Loons (some of the younger ones never did fly north!), along with
Red-throated Loons. The last two, Yellow-billed and Artic Loons, are seen only rarely this far
Here's the "diver" we see most often in coastal waters and bays, the Common Loon (Gavia
immer). This one was preening its white belly, and if you ever doubted the size and thickness
of his bill, he's putting your uncertainty to rest. The bump on the brow is more prominent than
in the other loon species, adding to the appearance of a flat-topped head.
3. Peregrine Power
The Outer Point was awesome yesterday, with good friends, calm seas, and great birds.
The usual Peregrine Falcons were present at the Lighthouse as we walked out, with the male
perched on a rock outcrop some 200+ feet below. He looked like a small black dot, but a 30
power scope view improves things a lot. Took a photo of the scene, and then of the bird
through the scope, to demonstrate the rather remarkable ability of digi-scoping to capture
distant birds. The Peregrine photo is cropped about 50%. The bird was actually even a bit
further away (smaller!) than indicated, as the scenic photo was taken with the camera lens
fully zoomed out to a short telephoto range of about 85mm, or about 1.7 X. Now you can see
why I get such a kick out of taking these photos. Last bit of technical stuff: the image of the
falcon in the scenic photo occupies a height of 19 pixels out of 2448 vertical pixels in the photo, i.e.,
less than 1%.
4. Little Yellow Job
Big birds tend to be easy to identify. The male ducks are usually distinctive, although the
females can be a bit dicey. Perched raptors require study, but usually give good clues if they
take flight. But the songbirds are another matter. Flycatchers are tough, especially the
Empidonax, which I leave to others. The little yellow jobs are a challenge for me, as they
rarely sit still long enough for a good look. Of course they are not yellow all over, but many
have yellow in the throat or breast, as here.
The absence of a supra-orbital ring or distinctive eye ring are against a vireo, as is the fairly
long fine bill. I'm learning that bill size and shape can be real important in placing the bird in
the right family. The main family that we need to consider are the wood-warblers, and many of
them have some yellow, especially in the throat, like Nashville Warbler, which has a nice
white eye-ring, unlike the minimal eye-ring seen here. Orange-crowned are not quite so yellow
as this, and Tennessee has a pale supercillium. Many with yellow in the throat have
distinctive facial patterns, like Magnolia, Cape May, etc. Yellow Warbler should always be
considered, partly because they are so common here. A closer look at the face gives us the
answer (I think!). We see the beginnings of a dark "mask" on the cheek. Doesn't match any of
the pictures in my book, but without the mask the bird looks like a female Common
Yellowthroat. If we imagine the mask getting larger and blacker, we can guess that this is
probably a young male Common Yellowthroat. This one was at the end of Harbor, at the
trailhead to Marta's Marsh (Corte Madeara). It ventured out to forage often enough for me to
grab a quick shot. Hope my I.D. holds up to scrutiny.
5. Long Leg
Legs... impossibly long, improbably pink... The lower tarsus is under water, so the "leg" is
even longer!But... the joint we see is of course the ankle, rather than the knee, so I guess we
should say that this bird has a very long FOOT.
It's our Black-necked Stilt, of course, Himantopus mexicanus. This is probably a male, with
deep black on the back. Female is a dark brown/black in the same areas. East Marin is great
Stilt territory, starting at Shorebird Marsh in Corte Madera, then north to Las Gallinas ponds
and Rush Creek in San Rafael. Taken at Shollenberger Park, Petaluma, Oct. 27.
We visited Shollenberger around 4 pm. The soft light late in the day is warmer, enhancing the
pink. More importantly, as the light gets less intense we see a compressed range in the
degree of brightness in our subject (dynamic range), allowing the sensor in the digital camera
to capture more detail in the white areas, which are so often "blown out" in photos taken in
bright sunlight. It also helps to underexpose by about 1 f-stop.
6. Pacific Golden Plover at Shollenberger Marsh
The big plovers are all very similar in appearance, but good light gives the Pacific Golden
Plover (Pluvialis fulva) an unmistakable glow. They were significantly smaller than the
Black-bellied Plovers feeding nearby. Not the greatest photo (they were 120' away), but
wanted to alert you about their presence. At least three Pacific Goldens have been hanging
around Shollenberger Marsh for a while. I saw these yesterday in the late afternoon at low
tide, looking south from the berm path that you take when leaving PRBO Conservaton
Science headquarters. The buffy eyebrow and prominent ear patch also help distinguish it
from the Black-bellied Plover. Photo not quite sharp enough to tell how far the wing-tips
project behind the tail, a feature that helps separate the Pacific from the American Golden
7. Lady Kestrel
Most days when you visit the Las Gallinas ponds there will be a female Kestrel perched
somewhere near the beginning of the paths leading out to the ponds. She's usually on a wire,
backlit, wary, and not nearly as captivating as she was this day when she alit on a snag for a
bit. I keep trying for a good photo of this beautiful animal, but something always seems to
block my path. Or maybe this bird is just too pretty to capture in a single shot. So I give you
this, a somewhat distant back view.
Note the rufous crown, not always present. Starting at
the tail end we see a rufous/black barring (the male tail has black band and then overall rufous
color), and then the black wing-tips, nicely outlined with white edges. The remainder of the
back, i.e., tertials, coverts, scapulars, shows rufous/black barring similar to the tail, strangely
blurred in this photo. Quite different from the blue-gray wings of the male. Strong facial
patterns similar on both sexes.
The American Kestrel is one of 13 Kestrel Species worldwide, and the only one found in the
Western Hemisphere (ref.: Birds of North America online). It is our smallest, most common,
and most widely distributed falcon, and happily one that doesn't mind hunting in areas
frequented by bipeds.