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Community Corner

On the Fly – A Love/Hate Relationship

A look at the wealth of bird life in and around Martinez, what to look for and where to look for it

You might, sometime, see a double-crested cormorant (Phalacrocorax auritus) sitting on a light post at the Martinez Regional Shoreline—or on a piling, on what’s left of the wreck of the Forester, or sometimes even on the pond, where it wouldn’t be too hard to dismiss it as a low-riding duck. But cormorants are in an entirely different family from ducks, in an entirely different order (Pelicaniformes). There are about thirty-nine species of them, and they occur all over the world, in coastal and inland waters.

The double-crested cormorant is the only one you’re likely to see in Martinez, though pelagic cormorants have been spotted at the Benicia pier. Brandt’s and pelagic cormorants are often seen in and along the San Francisco Bay, as well as the double-crested ones, which have been known to nest on the Richmond–San Rafael bridge.

A cormorant’s plumage is almost all black, unlike that of most of our local ducks, and its bill distinguishes it as well: the cormorant’s has a good-sized hook on the end, good for grabbing fish—which it does by chasing them underwater, pushing itself along with its powerful, webbed feet, even rounding the lenses of its eyes so it can focus better in the depths.

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As for telling the double-crested from other cormorants, its distinguishing features include an orange throat, orange on its face, and often an orange bill. The double crest isn’t easy to spot except maybe at the height of mating season, but it is quite a sight, looking something like the wings on Mercury’s helmet (as seen on the FTD logo). In England some cormorants are also known as “shags,” presumably because of their crests.

The most distinctive feature of all cormorants, even the flightless ones of the Galapagos Islands, is the way they stand with their wings spread (about a four-foot span) as if they were hanging them out to dry, which is in fact what they are doing. Their outer feathers, unlike those of most birds, aren’t waterproof. Maybe the added weight of water-saturated feathers makes it easier for them to dive deep and fast. The inner layer stays dry, providing insulation.

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Cormorants are an ancient family of birds, and the relationship between us and them goes back a very long way. Today in China, Japan, and Macedonia, and in the past in Peru, England, and France, people used them for fishing. There’s a good clip on YouTube from the BBC documentary Wild China of this ancient form of teamwork as it is practiced in China. The trained birds are treated with what looks like loving care when they’re not working. They go out on boats with fishermen, who tie a string around each bird’s neck to keep it from being able to swallow large fish. The bird dives into the water, catches fish after fish, and is called back with each catch to the boat, where the fisherman encourages it to cough up its prey. The families who do this keep several birds, and the daily haul is impressive.

In Europe, cormorants show up often in folklore and in heraldry. There’s even one on the coat of arms that Paul McCartney received in 2006. Well, it’s a “liver bird,” the ancient symbol of the city of Liverpool, but most depictions of that bird these days look pretty much like a cormorant.

The word “cormorant” may come from the Latin for "sea raven," or it may be a Celtic word. In Cornwall, the westernmost Cornish nation on the island of Great Britain, it was a giant named Cormoran and his wife who built the beautiful St. Michael’s Mount, but alas, their relationship to the birds is hazy. There are definitely cormorants, however, in the story of an ancient Cornish wedding feast, quoted here from Charles Kingsley’s Hereward, the Last of the English (1863):

Fat was the feasting and loud was the harping in the halls of Alef the Cornishman, King of Gweek. Savory was the smell of fried pilchard and hake; more savory still that of roast porpoise; most savory of all that of fifty huge squab pies, built up of layers of apples, bacon, onions, and mutton, and at the bottom of each a squab, or young cormorant, which diffused both through the pie and through the ambient air a delicate odor of mingled guano and polecat.

And this brings us to a source of both symbiosis and violence in the relationship between humans and cormorants: guano. Before the 1950s, when the “better living through chemistry” era began and synthetic materials became popular, bird poop, as well as that of bats and seals, was used to fertilize crops. Bird guano is a particularly rich source of nitrogen and phosphorus, and organic gardeners still fertilize with guano, much of it imported from Peru. (The guano of the Peruvian Guanay cormorant is particularly rich in nitrogen.)

The downside of this is that cormorants, having recovered their numbers since DDT was banned, have been nesting in huge colonies and defoliating entire small islands with their guano, which kills leaves. Double-crested cormorants are troublesome because they range so far inland, and they are also being accused of wiping out sport fisheries and ruining fish farms. There is a town in south Ontario where eleven pairs of cormorants arrived to nest in 1990, and now there are thirty thousand birds. Government agencies have employed many strategies to keep the numbers down, including (elsewhere in Ontario) a fleet of battery-operated dancing Santas, which is said to have caused a small decline or at least kept the birds from nesting on the ground.

There is some disagreement about how much cormorants are actually to blame for fish declines, and efforts by the governments of the US, Canada, and England to cull them by hunting are controversial. Here in Martinez, I don’t think I’ve ever seen more than one at a time, and maybe we should hope it stays that way.

Here is an interesting event: the Big Sit, for which birders are encouraged to sit still, preferably in relays, for a twenty-four hour period and note what birds they see within a predetermined 17-foot-diameter circle. It will take place on Sunday, October 9 this year. You can find more information at the Bird Watcher’s Digest website.

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