By Margaret Baird
When Jessica Almy recently came nose to beak with the
renowned mute swan of Eel River in Plymouth, Massachusetts, the
wildlife advocate for The HSUS Cape Wildlife Center immediately
understood why this large bird had frightened so many unwitting
boaters.
Sleek and elegant, haughty and hostile, the swan's puffed-up
posture and guarded demeanor was at first breathtaking to
behold as he glided beside Almy's canoe, a mere inches away.
But when he suddenly propelled himself forward, aggressively
kicking the surface and beating his wings, Almy's admiration
quickly turned to...well, to fear. Right then and there, she
decided it was time to paddle back to shore. This bird would
seem to have an anger management problem.
Indeed, he does. This swan has a history of aggression
toward boaters. "Genghis Swan," as locals have less than
affectionately dubbed the adult male, has even caused a few
canoes to capsize. The most infamous of the attacks occurred
last summer when the swan assailed a canoe party that included
kids, capsizing the boat and its charges, a scene that
instantly created panic among parents, children and Plymouth
city officials. People were calling for blood, which was why
The HSUS Cape Wildlife Center stepped in, but more on that
later.
In the swan's world, boats—at least the non-motoring
variety—are perceived as threats to his mate and territory. The
aggressive behavior of male mute swans during the spring
breeding and nesting season is well-documented. In defending
the nest, his mate or cygnets (swan chicks), males of this
species have been known to boldly chase or even attack other
wildlife, people, or watercraft if they feel threatened.
But the Eel River swan appears to be territorial year-round,
which translates into an ongoing conflict with human
recreational use of the river. And while defensively posturing
at boats as they pass down this quiet tributary isn't uncommon,
challenging or attacking boats when they mount a retreat is
atypical. It's what sets this formidable bird apart.
And that's why last summer Plymouth citizens and the town's
Board of Selectmen began calling for the bird to be relocated
or even killed. In the ensuing debate, the town, to its credit,
opted to take up The HSUS's offer to try non-lethal tactics on
the swan, in an attempt to discourage the bird from continued
advances on boaters.
By autumn, signs alerting boaters and other visitors about
the swan were installed along the river, and staff from The
HSUS and The Massachusetts Society for the Prevention of
Cruelty to Animals (MSPCA) began planning a humane conditioning
process in which the bird should ultimately learn to avoid
boats.
A Simple Plan
After discussing the matter with both state and federal
officials, HSUS and MSPCA staffers decided to employ aversive
conditioning, a humane training method by which an animal's
natural social dominance system is used to teach him to avoid
people—and in this case, boats.
The primary tools in the arsenal can include chemical
repellents, foggers, water pistols, and firecracker rounds.
When used by a trained person acting in a dominant manner,
these tactics frighten the animal, and cause him to associate
humans with negative experiences. Aversive conditioning has
been used with great success on black bears in several areas
where human-bear conflicts are a thorny issue, including
Yosemite and Great Smoky Mountains national parks.
Animals advocates are hoping to achieve similar success with
the Eel River swan. They launched the aversive-conditioning
campaign in mid-April with tools that would delight the average
teenage boy: water pistols and fogging equipment. Except that,
in this case, the pistols and the propane-fueled fogger were
filled with methyl anthranilate (MA), a naturally occurring
chemical compound, found in Concord grapes, which is used as a
food flavoring or as a fragrance additive.
But the compound has also been approved by the Environmental
Protection Agency for dispersing birds, whether to keep the
birds away from crops or from unwanted public areas. The
chemical repellent is often used to humanely deter Canada geese
from grazing sites, such as playing fields, where the animals
are at odds with people. When sprayed on grass, MA renders the
grass unpalatable, causing geese to seek food elsewhere.
For several weeks now, Almy and MSPCA staff have piloted a
canoe along the Eel River, armed with a special MA formulation
designed for dispersal into the air with a hand-held fogger
(marketed as Rejex-It® Fog Force). Whenever the swan attacks
their canoe, Almy and company either squirt him with the water
pistols or cloud him with the fogger—after carefully checking
the prevailing winds, of course.
In this situation, the chemical works as an irritant,
teaching the swan that attacking boats is an unpleasant
experience—one for which he'll receive a memorable but harmless
snootful of grape flavoring. The negative reinforcement ceases
as soon as the bird retreats.
After several aversive-conditioning sessions, the swan is
already beginning to think better of approaching passing boats.
"We [Almy and the MSPCA's Stephanie Hagopian] used spray
bottles during the first two sessions, then a Super Soaker
water gun and the propane-fired fogger last week," says Almy.
"We found that the swan responded most visibly to the fogger.
When he approached us as we were retreating from the nest, we
fogged him with MA, and he dunked his head in the water and
turned away."
When they retreated, the swan stayed at a distance and did
not chase the canoe when they turned back to shore.
While it seems to be effective, at least during these
initial runs, the technique is not an instant panacea, and it
will require persistence and time. The goal is for the swan to
associate the experience with all boaters, not individuals.
"I've come to really admire this bird," says Almy. "He really
has been through so much. We're making every effort to help
this swan and the Eel River community co-exist."
The Eel River case is just the latest example in The HSUS's
ongoing efforts to help communities find and effectively apply
non-lethal strategies for solving conflicts between wildlife
and people. "This project should serve as a role model for how
other communities can deal with wildlife conflicts," says John
Hadidian, director of The HSUS Urban Wildlife Program.
What You Can Do
You can help us help the Eel River swan. Please thank the
Plymouth Board of Selectmen for deciding to resolve this
problem humanely, and let them know that this approach could
become a model for other communities. Letters should be
directed to the Plymouth Board of Selectmen, Plymouth Town
Hall, 11 Lincoln St., Plymouth, MA 02360.
Margaret Baird is Assistant
Director in The HSUS's Urban Wildlife Program.