Gadwall - Anas strepera

Maybe I like the duck family because they're so easy to identify, as least regarding the male ducks, a.k.a. drakes. Female ducks are often called hens, but strangely enough they are all called "ducks".

The gray duck here is known as the Gadwall, Anas strepera - one of my favorites. The unaided eye sees him as a duck with gray body and head, black butt, and sometimes a white patch toward the rear (the "speculum", or the secondary inner wing feathers, seen well in flight).

Las Gallinas is a reliable spot for seeing Gadwalls, either in the slough along the west end or on the ponds themselves, especially pond #3. A slow walk will allow one to see them close at hand, as with this one on Dec. 29:

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The black and white feathers on the breast form a pattern of shingles, whereas those on the side and flank are seen as wavy lines that are called vermiculations. Most striking of all are the delicate feathers on the back, known as scapulars, and the long silvery feathers toward the rear that are the tertials (innermost wing feathers). The bill of the male is a plain dark gray.

The side view, taken seconds later, gives a better profile of the smallish bill and the not-quite-round head, along with the dark gray wingtips (primaries).

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Saw this young male Gadwall (Anas strepera) at Las Gallinas a few years ago. He was swimming with a female Gadwall, and I was struck by the fact that his head looked more like a female's, as it lacked the unusual male Gadwall's "puffy" profile, and the bill had orange on the sides like that of a female. 

The vermiculated pattern on the flanks has not fully developed.  So this makes him a hatch year male.

Here's another mature male from Las Gallina, with dark bill and a more typical profile.

Ruddy Duck - Oxyura jamaicensis

Ruddy Ducks are diving ducks in the subfamily (tribe) Oxyurini, the Stiff-tailed Ducks. In winter they are plentiful in the Bay Area, and are one of the species least bothered by human presence. At the Las Gallinas ponds they can often be viewed hanging out pretty close to shore, which may explain why I like to photograph them. Here's the female, seen at the southwest corner of pond #1. Head/bill profile pretty distinctive. Unlike the male Ruddy, she won't change a whole lot as the season progresses.

The male Ruddy Duck is easily identified by his white cheek, but in his early winter "basic" plumage he is otherwise much like the female. Note the stiff tail, a feature easily seen at a distance. The female can also raise her tail, but perhaps does do less often. As the winter progresses the bill color of the male will become dark blue, presaging a more dramatic high breeding plumage. 

An older photo shows how the male will look in the spring, with full ruddy color on the body, darker cap and tail, and unreal sky blue on the bill. Taken at Shollenberger Park in Petaluma some years ago.

Sharp-shinned Hawk - Accipter striatus

After a recent visit to Radio Road to check the water treament ponds I headed back along Redwood Shores Highway stopped at Avocet Drive. Near the parking area at the trailhead I was startled to see a young accipiter sitting calmly in a deep puddle and was able to get a few shots.

The strong streaking of the underparts is typical for a juvenile hawk, and the general structure was that of an accipiter. In winter we tend to see more Cooper's Hawks than the similar Sharp-shinned Hawk, but here the coarse streaking extended fully to the bottom of the belly, suggesting a Sharp-shinned Hawk. Here's another view, because I know how much people like reflections.  :)

The tail is not seen well, so we lose that valuable field mark (rounded tail in Cooper's, squared in the Sharpie). Soon the bird commenced bathing. Note how the head appears rounded in all these shots, another feature that favors Sharp-shinned over Cooper's.

The bathing proceeded in earnest, so I switched to video. Shortly thereafter the hawk was inadvertently flushed by a pedestrian heading out on the trailhead. Juvenile Accipiter Video. Hope the link works. Confirmations or corrections are welcomed, as I'm one of the last people to ask to identify these very similar accipiters.

Black Skimmer - Rhynchops niger

The Black Skimmer is a gregarious species, nesting in colonies that can exceed 1,000 birds. On the west coast they are seldom seen often north of the Oakland Bay Bridge, but they are regular at Radio Road in Redwood City. On my Jan 18 visit I noted 4 of them loafing on a close mud bar in the main pond.

The white nape will be gone with the advent of alternate plumage. Huge bill favors a male. No doubt you've seen videos of these long-winged tern-like birds flying low over the water with the lower mandible cutting a swath through the water, ready to snap shut when a prey item is encountered. Since they feed by touch they often are foraging at night, and most often spend the day resting with their buddies. You'd think that there would be serious drag from the large beak cutting through the water, but in fact the bill is so greatly compressed laterally that it meets with minimal resistance. Old shot from Florida shows the bill face on:

Many taxonomists currently place the Skimmers in a subfamily Rhynchopinae, within in the family Laridae (Gulls, Terns and Skimmers). Some think skimmers are more closely related to terns than to the gulls. In the North America the Black Skimmer is a coastal bird, whereas the other 2 Skimmer species (African Skimmer and Indian Skimmer) are found on the banks of rivers. Along our East Coast the birds head south to Florida for the winter, while those seen in California are largely sedentary. They are a species of concern, as reproductive success if quite variable (most years only 50% of pairs fledge chicks, and 2 chicks is about average (BNA #108, Gochfeld and Burger). Nesting failure more common in small colonies.