Flight Lines VIDEO: Mute swan, will it establish here?
Ever been on a carousel? Sure, we all have. That rickety circular contraption that goes round-and-round with all manner of colorful horse-like figures rhythmically bobbing up and down on gilded poles is typically the first carnival ride of a young person's life. The lines of riders waiting their turns are usually made up of young parents with toddlers plus the occasional couple looking for a romantic moment.
Somewhere in the collection of carved figures there is normally a stationary bench for those not wishing to do the yo-yo thing. More often than not the bench seat is decorated by swan figures. Specifically mute swans (Cygnus olor).
Mute swans enjoy a rich history in their native Eurasia where the huge fowl are associated with large parks and royalty. The Cornell Laboratory of Ornithology calls it the, "elegant bird of Russian ballets and European fairy tales."
We are all familiar with Anderson's, The Ugly Duckling.
As beautiful and as celebrated as this bird is, it was only a matter of time before Americans, desirous of its presence here, would bring it to the New World. Beginning in the mid-1800s, the ornamental bird was imported to bring sparkle and elegance to urban parks. Naturally, it didn't take long before the birds were self-sustaining and feral. Enter another unwitting example of exotic species invasion.
I bring this up because there is currently a mute swan in Southwest Cass County on Lake Bertha associating, improbably, with a native tundra swan. It represents the second instance of this species in North Dakota, the first being three birds that appeared briefly in June of 2012 at the West Fargo lagoons.
The beauty and grace of mute swans is arguably unmatched among waterfowl. Given its habit of mating for life, its all-white feathering, and the way it typically holds its neck in a graceful S-shape arc, mute swans have quite a following among romantics. It's been a subject for artists and poets for centuries in the Old World. That's the good stuff.
Now the not-so-good stuff.
Since becoming established in certain areas of the country (mostly in the Northeast and the Great Lakes states) mute swans have gained a reputation among conservationists and biologists as a sort of bully. It has been known to treat other native species of waterfowl very aggressively to the point of killing them.
The bird also is known for its voracious appetite, eating eight pounds of submerged plant material daily, thus having deleterious effects on wetland habitats. There is even a published story of a mute swan attacking and drowning a man in Illinois.
Yes, just like the zebra mussel, the emerald ash borer, leafy spurge, and Dutch elm disease, the mute swan is an exotic invader in ecosystems not equipped to handle them.
What to do?
Some state natural resource departments, worried about the survival of sensitive native species, have established protocols to control mute swans. Naturally this has generated a negative reaction among swan fans and animal rights groups. Again, science becomes mired in politics.
In my mind, though, it's deeper than politics, it's emotions. I firmly believe the existing research supports controlling these birds in the U.S. It's simply a case where this animal is so deeply rooted in literature and culture and our collective psyche, and is so pleasing to look at, that empathetic feelings trump common sense. Were it not so aesthetic to the human eye and instead looked like a cockroach or a snarling mongrel of some sort, plans for the culling of this species from America would meet little or no resistance.
A European scientific publication, Hyrobiologia, recently published a study of mute swans with regard to their effects and concluded, "Since there is a genuine risk of biological invasion, it can be considered as a safety measure to eradicate the species from North America. Culling or eradication may preserve ecosystem integrity, prevent an uncontrolled development of the mute swan population and may prevent a completed biological invasion."
While North Dakota is not in the immediate crosshairs of the mute swan, the two recent pioneering appearances suggest it's only a matter of time before they arrive. It may take decades but it could happen.
Perhaps it's better to plan for a response now, whatever that may look like.