…a species of medium-sized gull (Laridae) which breeds in local lagoons and lakes around the Mediterranean Sea and similar locations in the northwestern part of the Indian Ocean. Some populations will winter in north Africa and India. Like many other gull species, slender-billed gulls feed mainly on fish which are caught via plunge diving. However, they will also take insects and probe mud for various invertebrates.
NA Gull Identification Series:Part 6 “The California Gull”
In my previous two posts I covered two other species that fit the “small bright legged gull species complex that I made up” there is a third species that sort of fits this description. The California Gull (Larus californicus) of western North America is described as an intermediate between the smaller Larus delawarensus and the larger L. argentatus. California gulls are not endemic to California and can be seen inland in the western US and Canada during breeding season. They are also the state bird of Utah due to the fact that they helped with a plague of Anabrus simplex.
Unlike the somewhat similar Ring-billed gull, the California gull is a four year gull, taking four years to reach adulthood. Juvenile California gulls show a heavy brown wash along their body with scalloped barring along their mantle. Unlike ring-billed gulls California gulls show a totally black bill and barring on their undertail coverts which clash with the barring on the breast. They also can be separated from similarly aged herring gulls by the weaker barring on their coverts. (See Below)
1st-winter California’s start to lose the black on their bills giving them a two toned pink/black appearance. They also begin to show some wear on their scapulars which will show a grey coloration with subterminous streaks. The rest of the body stays mostly the same. At this stage they can be easily separated from similarly aged ring-billed’s which lose most of the brown wash on their body. They are also quite similar to herring gulls at this stage, but are smaller, don’t show a white hood on their head and generally have much darker tertial feathers. (See Below):
2nd-winter California’s undergo a more drastic molt, they lose most of their brown wash and grow in pretty white feathers. They form a grey “saddle” on their mantle. Their coverts and tertials start to lighten out but they still retain some barring across their body. They can be easily confused with a late 1st winter/1st summer ring-billed at this stage, but can be distinguished by their darker upperparts, more greenish bill, and less worn tertials. They are also fairly similar to 3rd winter herring gulls, but are smaller and have smaller bills, darker upperparts, and dark eyes. (See Below):
During their third winter California gulls start to show some character, at this stage they are very similar to an adult winter bird but still have a two toned greenish pink bill, and some barring on their coverts. Their bill also starts to show a two toned red and black gony spot. However their most defining feature is their greenish-yellow blue-green leg color which sets them apart from other gulls. (See Below):
Breeding adult California gulls are fairly unmistakable, they show a clean white color along their body with a darker mantle than seen in a ring-billed gull. Their bill shows both a red and black spot on it, and their legs are a greenish color, which makes them easy to separate from other gulls. (See Below):
*There is a subspecies of California gull known known as the Northern Great Pains race (L. c. albertaensis) which generally shows a longer bill and generally more white wingtips with a whole white tip to P10.
The Kelp Gull, Larus dominicanus (Charadriiformes - Laridae), also known as the Dominican Gull, breeds on coasts and islands through much of the southern hemisphere.
It is found on a number of subantarctic islands, on the Antarctic peninsula, on the southern coast of Australia and all of New Zealand, on the southern cost of Africa and Madagascar, and on the coast of South America as far north as Ecuador and southern Brazil.
Also known (incorrectly) as the red-billed gull, the dolphin gull is a species of gull native to Chile, Argentina and the Falkland Islands. Like other coastal birds the dolphin gull feeds mostly on invertebrates, like mussels and other molluscs but they are opportunistic and will take other food like carrion as well. Dolphin gulls frequent rocky and sandy shores and can commonly be found with other seabird colonies