Our Mute Swan Problem
Much attention has been focused recently on one big white bird, the snowy owl, but another still larger avian species is also in the news, the mute swan.
Unlike those other introduced bird species, the starling and the house sparrow, the mute swan is a handsome bird, perhaps best known to us from Hans Christian Anderson's story of "The Ugly Duckling," that matures to become, in Anderson's description, "the most beautiful of all the birds."
This species comes to us with another legacy. In England's past, mute swans were domesticated for food. Farmers identified their birds by nicking their bills or feet and registering those marked birds with the Crown's representative, the Royal Swanherd. Birds not so marked were considered Crown property and so the mute swan has become known as the Royal bird.
The mute swan should not be confused with our native tundra swan. Tundra swans migrate through this region on their way from their wintering grounds along the Atlantic seaboard south of Pennsylvania to their breeding area in the tundra of the farthest northern reaches of this continent. Tundra swans are easily differentiated from mutes by their bill color: the mute's orange, the tundra's black.
Mute swans were first brought to North America in the late 19th century. Until about 1970 they remained uncommon, most found in park ponds where they had been introduced. From that time on, however, their population has increased exponentially, doubling every seven or eight years.
Today in New York State there are over 2000. Well over half of them are found on Long Island and in the lower Hudson valley but their numbers are increasing rapidly in western New York as well: for example, 15 have been recorded recently in Wilson Harbor where for many years there were only two and you can now find 65 in Irondequoit Bay near Rochester. One possible reason for this increase may be the recent replacement of lead fishing sinkers and shot with less toxic substances. The swans had been among the waterfowl poisoned by discarded lead that they swallowed when feeding.
To many people that all sounds fine. Here is another beautiful bird to be seen more often.
Unfortunately, the mute swan is a problem species. These big birds rapidly deteriorate the quality of any marsh they inhabit. They feed year round almost exclusively on submerged aquatic vegetation, each day consuming over a third of their body weight. Their voracious appetites quickly deplete this important marshland component that supports fish and other wildlife. They overgraze an area, destroying its value, and then simply move on, leaving the aquatic equivalent of a desert. In this they differ from tundra swans that feed mostly on mollusks and land-based crops.
Mute swans are also intolerant of other species, driving away or even killing rails, ducks and geese. They are even aggressive toward people. And where these swans congregate their feces significantly increase the coliform count.
In response to these problems, the New York's Department of Environmental Conservation (DEC) has proposed a management plan for mute swans. Here is the key wording of that plan: "DEC has been operating for close to 20 years under a management policy that permits removal of mute swans from lands administered by [the state], prohibits release of captive mute swans into the wild and authorizes issuance of permits for swan control by others on a site-specific basis. This new plan supports further action by DEC to eliminate free-ranging mute swans from New York by 2025, while allowing responsible ownership of these birds in captivity."
The response to this plan has been, as I expected, very strong. Here are just a few reactions: "You better not mess with them." "First the deer, now the swans, next it will be the poor." "Man is the invasive species." "Doesn't anyone respect God's creatures?"
I side with the DEC. I see their proposal as thoughtful, appropriate and necessary. Yes, the mute swan is beautiful but it deserves the same consideration as those less attractive invasives: the Norway rat, the European starling and the Emerald Ash Borer.-- Gerry Rising