Mute Swans: Know Your Argument
By Jim Ochterski
RBA Conservation Committee
As of late February 2014, the NYSDEC announced in a press release that they will revise their management plan regarding the methods for eradicating Mute Swans from New York State, focusing on regional approaches and “non-lethal means to achieve the management plan’s intended goals.”
Here is a very condensed background: Imported from Europe 100 years ago, Mute Swan populations in Upstate New York are surging unexpectedly. They have a reputation for gorging messily on aquatic vegetation that disrupts fragile aquatic habitats. There are many reports of aggressive behavior toward other breeding waterfowl and humans. Therefore, the NYS DEC is proposing to eradicate this non-native species within the next 12 – 15 years, partially by capturing adults and killing them, while taking measures to destroy the viability of eggs when they nest. The Rochester metro populations of Mute Swans are increasing faster than other areas due to swan-friendly freshwater lakeshore / human residential habitat.
The Mute Swan controversy is a complex mix of science, ethics, precautionary actions, and personal values. If you wade into the waters of this controversy, it is a lot less certain than you might think. Corey Jager, a recent graduate from the Masters-level Fisheries and Wildlife program at Michigan State University wrote a one-of-a-kind thesis in 2013 that digs down to the root of the arguments for and against lethal approaches to Mute Swan management. He analyzed the logic of the main opposing arguments and found both sides were using incomplete information to draw conclusions.
Look at the breakdown of the “ecosystem protection” argument in favor of controlling Mute Swans:
1. Mute Swans always consume vegetation in a manner that limits plant regeneration (probably true),
2. Limited vegetation diminishes the diversity of flora and fauna (true),
3. A healthy wetland habitat has diverse flora and fauna (sometimes),
4. Controlling all Mute Swans that reduce vegetation will foster a healthy wetland habitat (maybe),
5. We should preserve healthy wetland habitat (true),
6. It is wrong to control Mute Swans without an adequate reason (true),
7. Preserving healthy wetland habitat is an adequate reason to control the Mute Swan population (maybe).
Conclusion: Therefore, we should control New York’s Mute Swan population.
Unfortunately, the sometime’s and maybe’s leading to the conclusion weaken the final statement.
Look at the “killing them is the best approach” argument:
1. Killing Mute Swans is the most effective and efficient population control method (possibly not),
2. We should use the most effective and efficient methods to control New York’s Mute Swan population (true),
3. It is wrong to kill a living being without an adequate reason (almost always),
4. Effective and efficient population control is an adequate reason to kill living beings (true for some people, but not everyone).
Conclusion: Therefore, if we control New York’s Mute Swan population, we should kill them.
Unfortunately, this set of arguments is also faulty as it mixes economic justification with biological evidence about population control.
Mute Swan advocates might look at it like this:
1. Killing Mute Swans as a method of population control is inhumane (true for some people, but not everyone).
2. If we are to control the Mute Swan population, we should use humane methods (true).
3. A method of population control that does not include killing living things is a humane method (mostly true).
4. Nest and egg destruction and relocation do not require killing Mute Swans, and are therefore humane (sometimes).
Conclusion: Therefore, if we control New York’s Mute Swan population, we should only use nest and egg destruction.
Like the previous arguments, this one is also beset with limitations and half-truths.
When you see a few or many Mute Swans and feel your emotions rising for them or against them, recall that there are many others who feel that same passion, but often in a different direction than you. When we talk or write about the subject, we need to make sure we are committed to acknowledging where our firmly-held conclusions may actually be a little weak.
Source: Michigan Mute Swans: a case study approach to ethical argument analysis, a thesis paper by Corey A. Jager; Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Fisheries and Wildlife – Master of Science (2013)