A campaign to limit the gosling hatch in four Rochester city parks follows guidelines approved by the Humane Society of the United States and People for the Ethical Treatment of Animals.
Here are a few things to know about the process that is starting this week:
1. Options exist for addling
PETA lists oiling or replacing eggs with ceramic substitutes as its preferred methods for managing the goose population.
While it also includes shaking or puncturing eggs as humane options, PETA says those methods are more difficult and can produce a deformed gosling, if not done properly.
2. Destroying nests not as effective
While permits allow for destroying nests during the nesting period, the Humane Society states some geese will build new nests and lay additional eggs.
By treating eggs, the geese are encouraged to maintain the existing nests until the season passes.
3. Addling is not a one-person activity
Since geese actively defend their nests by challenging strangers, the addling process requires one person to treat the eggs with corn oil and at least one more to provide protection for the work to be done.
Some geese also need to be gently moved off nests.
Goose defenses typically include honking, hissing, flapping wings and charging toward the threat.
Tom Keefe of Canada Goose Management Inc. said an experienced two-person team can do the work, but up to four or five new volunteers could be used to treat a nest.
4. The effort doubled in size from first proposal
The Rochester Park Board initially approved a volunteer project to addle eggs in Silver Lake and Cascade parks, but later signed a contract with Canada Goose Management to treat eggs in Foster Arend and Soldiers Field parks.
In addition to the work in the two parks, Keefe agreed to train volunteers in the practices he’s used in other Minnesota communities.
5. Addling requires permits
Interfering with the nests and eggs of Canada geese is illegal without approval from the U.S. Fish and Wildlife Service and Minnesota Department of Natural Resources.
The Rochester Parks and Recreation Department’s state permit authorizes egg oiling and related tasks until sunset June 30.
The permit does not allow for injury of the federally protected geese, which is a criminal offense.
6. Incubation is tested
Eggs do not start to incubate as soon as they are laid, so cold eggs in the nest have not started the process.
A "float" test is used on warm eggs to determine whether incubation is less than 14 days of the typical 28-day period. Eggs that float are considered too old to addle and returned to the nest without further interaction.
The Humane Society and PETA consider addling eggs before 14 days of incubation to be humane.
7. Targeting the resident population
The nests in Rochester parks are for the geese that stay in the city throughout the year.
The majority of geese seen in Rochester migrate through the area and do not nest here.
8. Elimination is not the goal
Laura Settle, who is coordinating volunteers for the addling effort, said the primary goal is to maintain a socially acceptable goose population in areas without natural predators.
“It’s fun to see little goslings in the spring, and it's fun to see wildlife,” she said. “One of the things I like about living in Rochester is all the wildlife, but if the population gets too big, it’s not going to be enjoyable.”
9. Nests and egg numbers are documented
Recording the location of nests and the number of eggs allows addlers to return to see if their efforts were successful, as well as document whether additional eggs were laid.
It will also allow volunteers and Canada Goose Management Inc. to revisit the sites and remove unhatched eggs once the nesting season ends.
The records are also required by the Minnesota Department of Natural Resources.
Documentation includes date, location, egg numbers, addling method and who was involved.