Black Skimmer feeding in the wetland channels at Bolsa Chica Ecological Reserve.
With an average wingspan of over three-and-a-half feet and of one the largest bills in the water or out, the Black Skimmer attracts attention. It has black wings and a black back when viewed from above and the underside of its wings are white. Its bill is a red-and-black and very large. Another unusual feature that you will not see is the vertical pupil that is like a cat's. It is thought to be a protection against the bright light of day. Like many terns it has webbed, brightly colored legs and feet. It is rare that I do not see Black Skimmers at Bolsa Chica, and I often see them at the Upper Newport Bay. I have also seen them on occasion at San Joaquin Wildlife Sanctuary which is very close to the Upper Newport Bay. The sight of the large, almost completely black wings skimming over the water is something to see. They move fast while skimming. They are often there and gone before you know it.
Flying by wintering American Avocets. Getting ready to dip down again into the channel.I see Black Skimmers hanging out on the shore or in the shallows in groups, but feeding is usually a one-bird operation. They may leave in a pack, but Black Skimmers break up and usually hunt alone or with another bird or two.
Black Skimmers resting in shallow water at Bolsa Chica Ecological Reserve.
Black Skimmers are not quiet birds. They gather and fly off to fish in noisy, barking groups. They hang out with other birds on the shore or sand spits. They are a very sociable, outgoing group.
Black Skimmer against a backdrop of Willets at Upper Newport Bay.
Their feeding technique is what gives the Black Skimmer its name. The key is its unusual bill. The bottom mandible is much longer than the top one which means it can stick the bottom mandible into the water and snap up fish easily. Its bill is very, very thin. In fact when you see how thin it is, it's a shock. It is unexpected. But it is a very sensitive bill. Because the Black Skimmer feeds by feeling the fish or other food in its bill, it does not need to see its prey. In fact, the Black Skimmer is often a nocturnal feeder. However, mainly it also feeds early in the morning and late at night. In addition, you may see them feeding all day in breeding season. So the Black Skimmer has it covered. Whether it is nocturnal,
crepuscular, diurnal, or all three, it may be out there skimming for fish and other critters. (If you wonder how to say "crepuscular," check it out in the Merriam Webster Dictionary here. Click on the little red speaker and a pronunciation screen will pop up and say it for you. If you have a pop up blocker, hold down the control button on you PC while you click the speaker and it will allow the pop up.)
Black Skimmer feeding in Bolsa Chica Ecological Reserve.
From the US Fish and Wildlife Service, some diet information: "At Bolsa Chica in 1995-1996 northern anchovy (23.6%) was the most commonly taken prey. Topsmelt (15.0%) California sardine (11.6%), California grunion (5.3%), California killifish (3.6%), mosquitofish (6.2%) and shadow gobies (8.6%) were also regular prey items."
Showing the white underside of its wings as it banks for a turn. Black Skimmers live from 5-20 years. So when you see Black Skimmers, some may have been around for more than a few seasons.
Black Skimmers are seasonally monogamous. Sexes are the same, except the male is bigger. They have a courtship that involves the male giving the female a fish or other token. The breeding season is five months long from April through the beginning of September. Females usually begin to breed at about 3 years old and males not until 4 years. Parents take turns on the nest brooding the young.
Black Skimmers in the Americas are very much a coastal bird. They cover the Atlantic coast from south from Massachusetts, through the gulf into Central and South America. They moved in to California from Mexico.
Black Skimmer skimming.Although the Black Skimmer is listed as a Species of Special Concern in California, the range of the Black Skimmer is expanding. Black Skimmers began appearing in California in the 1960's and breed regularly in the Salton Sea. Black Skimmers appear to have begun breeding in Orange County in 1985 at Bolsa Chica. The following year they began breeding at Upper Newport Bay. They also appear nearby in the San Joaquin Wildlife Sanctuary. So, they are a recent Orange County immigrant. I have seen them in Long Beach as well at the Golden Shore Marine Preserve. After breeding, they scatter to wintering areas in Southern California and into Mexico. Some do stay in the breeding area.
So when you are out birding in Orange County, watch for the large bird with the big bill skimming the surface of the water. You just might see the Black Skimmer.
Pictures Below Courtesy of the US Fish and Wildlife Service
Courtesy US Fish and Wildlife Service--photographer Gary Kramer
Courtesy US Fish and Wildlife Service--photographer Gary Kramer
Courtesy US Fish and Wildlife Service--photographer George GentryVery comprehensive article on the Black Skimmer.
Audubon Watchlist: Black Skimmer
Good information from Audubon.
Good Videos of Black Skimmers--many in Mexico. Great view of the Black Skimmer's thin bill.
SORA: On the Slit Pupil of the Black Skimmer
Journal Article on the pupil of the Black Skimmer. Remember to page down a little for the start of the article. The page starts with the end of the previous article.
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