from The Kingbird 51: 2 (June 2001) 575-578
THE QUESTIONABLE WISDOM OF INTRODUCING ALIEN SPECIES
Gerry Rising
In January 1988 a Trumpeter Swan was found in the upper Niagara River offshore from Fort Erie, Ontario. I was one of those who crossed the Peace Bridge to observe this bird -- and to add the species to my life list. Increasingly over the years since then, I have been concerned about that decision. Accumulating lists represents the sport of birding and I do not denigrate that activity. "Listing" drives the more serious study of ornithology in the same way that a hobbyist accumulating a co llection of insect specimens moves forward the study of entomology. But there must be limits. That bird was almost certainly raised and released by Canadian aviculturists who have been breeding Trumpeter and Whooper swans for some years.
Consider a rather obvious example. There are a number of people in western New York who, as an avocation, raise exotic (and usually beautiful) birds: Golden Pheasants, Mandarin Ducks and Cinnamon Teal, for example. Now suppose, as often happens, one of those birds escapes, perhaps walks across the road from the game farm. Should I count it? Rather obviously not!
But now consider a more serious concern. In an article that provides an excellent survey of current records (Carroll and Swift 2000) we read, "In 1996 wild Trumpeter Swans were confirmed breeding in New York State for the first time in recent history." I am troubled by that sentence and with the discussion about the earlier history of this species in New York on two scores and I will explore those concerns.
Let me stress here my high regard for the authors. I consider Dan Carroll, with whose work I am acquainted, one of the finest naturalists of western New York, and I am advised that Bryan Swift is of equal caliber.
First, I believe that the phrase "in recent history" is incorrect. The best evidence I find is that Trumpeter Swans never bred in New York State. Consider, for example, the range map that appears on page 61 of Handbook of North American Birds , Vol. 2 Waterfowl (Part 1) edited by Ralph S. Palmer. The historic breeding range of the Trumpeter Swan on that map extends only east as far as central Michigan, 250 miles west of westernmost New York State.
Second, according to my research, Carroll and Swift are in error when they say that the Trumpeter Swan "was once common throughout the northern United States, Alaska and Canada. The historic breeding range extended in a wide band from the Bering Sea east to the Atlantic Coast and south to northern Kentucky, northern West Virginia, northern Maryland and northern Delaware."
The first sentence is incorrect and the second sentence, which at least qualifies the first, is still wide of the mark. Indeed there are Trumpeter Swan records from the states mentioned. In addition the authors refer to two historic records of dubious origin in New York State (Eaton 1910) and one prehistoric record in Orange County, NY (Steadman 1998) but none of these was part of a breeding population. Given the lack of supportive evidence, we can only assume that they were migratory birds.
The following paragraph states, "This bird was extirpated from the Atlantic Flyway by the early settlers almost 200 years ago."
The Trumpeter Swan population that wintered along our southern Atlantic Coast was indeed decimated by early hunters and that had a significant effect on the entire population of this species. In substance then, the sentence is on the mark, but these we re not birds of the Atlantic Flyway. These were birds that migrated southeast from their midwestern and western breeding range to winter along the Atlantic and Gulf coasts from the Carolinas southward. The best summary of the views I have expressed here was by Bill Whan (Whan 2000). Although he writes about Ohio, his message speaks to us, still farther to the east.
Finally, as Carroll and Swift carefully note, these newly breeding Trumpeter Swans are, with little doubt, escapes. That places this species in the same category as the escaped European Goldfinches that briefly nested on Long Island (Elliott 1968, Linc oln 1998.)
Which brings me back to modern times. The survey by Carroll and Swift of recent Trumpeter Swan records ends with an invitation for "readers to offer their views about whether an active restoration program would be desirable." Unless the analysis I have provided here is incorrect, the word "restoration" is inappropriate. It should be replaced with "introduction." And I voice my strongest possible opposition to that introduction.
The Trumpeter Swan is indeed a beautiful bird, but so too is the Canada Goose -- unless you happen to own a golf course. But I don't oppose the introduction of the Trumpeter Swan simply because we have trouble with Canada Geese, Monk Parakeets, Europea n Starlings and House Sparrows. I oppose it because it is an alien species to this region! To argue, as I have heard, that the Trumpeter Swan will shoulder out the problem Mute Swan is simply speculative nonsense. That reminds me of the apocryphal story I used to hear many years ago about the introduction of the European Starling, which claimed that a European Starling that was caged with an English Sparrow killed the smaller bird, leading to the assumption that the starling would control the House Sparro w population.
I believe that we need to think much more seriously about introductions, or even reintroductions, of any kind -- and in this regard I salute the DEC for its current policy (as stated by Carroll and Swift) of "hands off' or at least "wait and see".
Unfortunately there is some slippage in this policy, most notably continuing attempts by a group called Environmental Studies at Airlie (www.trumpeterswans.org) located in Warrenton, Va.. Oddly, they are associated with the International Academy for Preventive Medicine. Their goal is to establish a migrating population of Trumpeter Swans to fly back and forth from near the Iroquois National Wildlife Refuge to Chesapeake Bay. The process is a current ornithological fad - movies included - better used to reestablish and improve an historic Whooping Crane population.
I had an opportunity to observe this group's laughable first attempt to carry out this task in 1998. The idea is to associate the swans with ultralight aircraft and get them to follow the flight of those planes. The team leader of this project (from Gr eat Britain) insisted that this was "reestablishing a flight pattern." When I pointed out to him that historically the birds neither bred here nor wintered in Chesapeake Bay, he insisted that I was misinformed.
The Trumpeter Swan cygnets were raised and cared for by young women; the pilots were both men. It was great fun to watch the local "training" flights. Once the birds were able to fly, they were transported to a runway where they were encouraged to foll ow the planes as they took off. The planes started away and the young women waved their arms and "whooshed" the birds off to follow their ultralight leaders. They did so for about a quarter mile but then a few at a time peeled off to return to the care-gi vers on whom they were imprinted. It was simply nonsense of the worst kind and the later attempt to get the birds to follow the planes south was not only an abject failure but also a minor disaster when one of the birds was crippled by a collision with on e of the aircraft.
The whole project is, I suggest, absurd and should be terminated. This is not appropriate biology or conservation and the quite substantial funds could be far better used for almost any other activity.
There is a great deal of evidence that fooling with Mother Nature is often not in our or the birds' best interests. We need only look at the extreme example of Hawaii to witness this at its worst. Consider as well, two of our own game birds. On one han d we have the (alien) Ring-necked Pheasant. Since massive releases have been largely terminated, it is now an uncommon to rare species here in western New York. In the 1950s a state wildlife publication calculated the cost of stocking per bird taken by hu nters at over $13. We can only imagine how far hunting permits go to pay for stocking some forty years later? Flying directly in the face of our U.S. experience, Ontario wildlife authorities are currently considering a massive introduction of Ring-necked Pheasants.
On the other hand we have a wonderful example here in New York of the reestablishment of the Wild Turkey. Contrary to what is often claimed, this was not accomplished through releases. This species reestablished itself the right way! It spread n orth from historic population remnants in Pennsylvania.
I urge not only that we discourage further attempts to manipulate wild bird populations through releases, but also that we develop and implement laws to prevent such activities.
Literature Cited
Carroll, D., and B. L. Swift. 2000. Status of the Trumpeter Swan in New York State. Kingbird 50: 232-236
Eaton.E.H. 1910. Birds of New York State State University of New York, Albany. Part l, p. 239
Elliott, J. J. in Bent, A. C., et al. 1968. Life Histories of North American cardinals, grosbeaks, buntings, towhees, finches, sparrows and allies, Part 1, pp.384-397
Lincoln, S. R. 1998. in Bull's Birds of New York State. ed. Emanuel Levine, Cornell University Press, pp. 572-573
Steadman, D. 1998. in Bull's Birds of New York State. ed. Emanuel Levine. Cornell University Press. pg. 68
Whan, B. 2000. Did Trumpeter Swans Ever Breed in Ohio? The Ohio Cardinal 24 (1): 30-46
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