It’s the classic story of unintended consequences.
In 1890, Eugene Schieffelin released 60 starlings in New York’s Central Park with the hope of establishing a breeding population. Just in case the experiment wasn’t successful, he released another 40 the next year.
Schieffelin was a big Shakespeare fan and he wanted to bring to the New World all the European birds mentioned in The Bard’s plays. Starlings appear in Henry IV, Part 1, in case you are wondering. Schieffelin was also a member of the American Acclimatization Society, a group that advocated shifting species around the globe. It apparently seemed like a good idea at the time and had the support of a lot of scientists. Now we know it’s not. But it’s too late.
Schieffelin’s starlings multiplied and multiplied and multiplied. Today, there are millions of them in North America, all descended from those Central Park birds. The species, originally from Eurasia, has also, with human help, been introduced to places as diverse as the Falkland Islands and Fiji, South Africa, and Mexico.
Starlings are a poster bird for introductions gone wrong. “The starling is undoubtedly one of the least loved birds in North America, for it . . . crowds out other species and its bothersome population growth seems to have no clear end in sight,” wrote Donald Stokes in his Guide to Bird Behavior, Vol. 1. “In these respects, Sturnus vulgaris is very similar to Homo sapiens.”
But more than a century into its occupation of North America, is the starling still as bad as Stokes described it in the late ‘70s? Uh, pretty much.
The starling is the worst of the “big three” imported avian invasive species, said Kevin McGowan of the Cornell Laboratory of Ornithology. The other two? The house sparrow (which Schieffelin also had a hand in introducing) and the common pigeon.
“They’re really active competitors for nest holes, which are an attractive commodity and there aren’t enough holes to go around,” McGowan said.
It’s hard to get a grip on the starling population. BirdLife International estimates more than 310 million around the globe. Partners in Flight puts the worldwide population at 150 million, with 45 million in the U.S and 12 million in Canada. One US Department of Agriculture research paper published in 2007 put the US population at 200 million, or a third of the global population.
Needless to say, it’s a lot.
Starlings are successful as a species because of their toughness and their personality. Pugnacious is the word McGowan uses to describe them. Last winter he watched a starling lay claim to his suet feeder during a blizzard and defend it against all comers, including a pileated woodpecker, for an entire day.
McGowan said the starling’s attitude is matched by its physique. A starling weighs about 85 grams. A bird that size typically only weighs about 50 grams. “It’s solid muscle. They’re stocky and muscular, which makes them pretty effective competitors against other birds.”
Starlings are also intensely social, gathering in huge flocks at all times of the day and every
season. They swoop through the sky, the shifting black mass looking like nothing so much as smoke in the wind. The flocks are called murmurations. They fascinate scientists who have spent a lot of time trying to figure out how the birds position themselves in such huge, constantly shifting airborne flocks without bumping into each other.
The flocks make the starling an agricultural pest. They can swoop in and clean up tons of insects and grubs, or they can swoop in and do a lot of damage to crops. The federal government spends serious money every year killing starlings and other blackbirds.
The starling is not a sweet singer, its vocal repertoire consisting mainly of squeals, squeaks, and chortles. But it is a gifted mimic. The passage in Henry IV? It had to do with the starling’s powers of mimicry. And starlings actually make good pets. Noisy, but good. “I had some friends who had one that would respond when it was called,” said McGowan. “They’re social, so when they’re raised from babies they like people and want to interact with them.”
“They’re fascinating animals, beautiful, with iridescent feathers, and just as interesting as all get out,” McGowan added. “They do fit into the urban environment. They’ve adapted to do that.”
And there is evidence that the starling’s population rise might have halted, he said. The US Geological Survey’s Breeding Bird Survey shows a steady decline between 1966 and 2015; BirdLife International’s starling factsheet notes a “moderate” decline in Europe. No one knows why. It could be mechanization of agriculture, the loss of grasslands in the East to regenerating forest, or the ongoing campaign of death waged against them by the Department of Agriculture. Or a combination of those or other factors.
But it isn’t likely that this avian invader will be eliminated from our landscape anytime soon. “I would never say never,” said McGowan. “After all, look at what we did to the passenger pigeon in only a few generations. But it’s unlikely.”
Joe Rankin writes on forestry and nature. He tolerates starlings. The illustration for this column was drawn by Adelaide Tyrol. The Outside Story is assigned and edited by Northern Woodlands magazine, and sponsored by the Wellborn Ecology Fund of New Hampshire Charitable Foundation.