Infectious Diseases: Kill Those Pigeons?

In Daphne du Maurier’s story and Alfred Hitchcock’s movie, The Birds, it is the birds that go berserk and attack man. Last week in New York City, it was man who, after generations of meek submission to fowl indignities, turned upon the birds. The city government was considering exterminating the pigeons that drop their excrement on park benches, statues and hurrying pedestrians. City officials are convinced at last that the pigeons — up to 5,000,000 of them, by some of the wilder estimates — are an intolerable menace to health.

At least two deaths this year have been definitely traced to infection by pigeons.

In its natural habitat on European cliffs, the rock dove (Columba livid), with its grey coat, white rump and iridescent head and neck, is an attractive bird. Bred and trained by man, it has become a valiant message carrier, famed for its speed and homing instinct. It has also become a multicolored pest, appealing mainly to snapshooting tourists and aging lonelyhearts who get solace of a sort from feeding the flocks.

Hot Blood. The pigeons of St. Peter’s in Rome, St. Mark’s in Venice and St. Paul’s in London are so entrenched that no public official would dream of killing them. The French have prohibited the feeding of pigeons in Paris, but they don’t enforce the law. Moscow is attacking its pigeons surreptitiously to avoid exciting the pigeon lovers.

Pigeons carry the infectious agents of a dozen diseases. They may reward the owner of the hand that feeds them with a dose of ornithosis (better known as psittacosis or parrot fever). In New York and probably in most U.S. cities, pigeons are also the principal carriers of the fungus Cryptococcus neoformans, or CN. The fungus does not seem to make the birds sick, perhaps because their blood heat is too high, but they drop it all over the place in their excreta.

And while desecrated, defecated-on statues are immune, live human beings are not. For them, cryptococcosis may be a severe or even fatal illness, usually caught by inhaling dust from pigeon droppings.

When the fungus goes no farther than the windpipe and lungs, it may touch off what seems like a bad cold. More severe cases are often mistaken for bronchitis and tuberculosis. But the deadliest form of the disease is inflammation of the brain covering. Cryptococcal meningitis was always fatal until the antifungal drug, amphotericin B, came into use six years ago. Now the death rate is down to about 30% of meningitis victims. But nobody knows exactly how many cases of CN lung disease there are because the vast majority are not diagnosed correctly. New York City records about 20 cases of CN meningitis each year, with several deaths.

Roost No More. In other U.S. cities, many health authorities pooh-pooh the idea that pigeons are a common cause of illness. But downplaying the danger is a mistake. CN meningitis is increasing in Chicago, and one suburban doctor has had five cases this year.

Some cities have wasted tens of thousands of dollars on futile efforts to keep pigeons away from public buildings with electrified grids, netting, dummies of cats or snakes, and supersonic howls. They might as well have put up a sign, “No Pigeons Allowed”—which is said apocryphally to have happened in Philadelphia’s Rittenhouse Square. The most effective columbifuge so far seems to be a gooey chemical trade-named Roost-No-More, which is smeared on the cornices of buildings. It gives the pigeons a mild hotfoot, and they avoid its smell.

At least two cities have declared open war on pigeons and are winning. Cincinnati, where eleven city workers became ill, and one died, after cleaning out pigeon droppings from an abandoned water tower, has started strict enforcement of an anti-feeding ordinance. Fines up to $50 for violators have made the pigeon rara avis there. Authorities in Buffalo are also making a fight to the finish. They employ five fulltime exterminators, who trap pigeons wherever they can and unobtrusively kill them by wringing their necks. The exterminators are also crack marksmen and shoot pigeons downtown in the early morning.

New York City sentimentalists raised such a howl last week that authorities did not know how to get rid of the birds without losing the pigeon-fancier vote. To trap and kill the birds, they would probably need an amendment to the state conservation law. A few do-it-yourselfers were reported baiting the pigeons with corn, then clubbing them to death with baseball bats. A more scientific and humane though admittedly long-range remedy was proposed by an ornithologist: let the city feed the pigeons all they will eat, but have the corn treated with chemicals that will make the birds sterile.

* In Cincinnati, by coincidence, the last of the native passenger pigeons (Ectopistes migratorius), which once darkened Midwestern skies in flocks of billions, died in the zoo in 1914.