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At one time resident Canada geese populated the pond area behind
the Government Centers main building. After beavers removed
most of the trees from the pond edges, increased sunlight allowed
a proliferation of weeds and brush to grow around the pond.
Predators of geesesuch as foxes and raccoonmay use
this type of habitat for hunting, which discourages geese from
settling near it.
In contrast, the Herrity Building pond and decorative fountain
provided ideal conditions for geese. Manicured grassy open space
adjacent to the water provided a constant source of food. Eroded
banks with little vegetation gave the geese easy access in and
out of the water.
To further entice the geese, some visitors to the three-building
Government Center complex tossed food in the pond. Feeding bread
and popcorn is unhealthy for ducks and geese, makes them dependent
on humans, and may make them aggressive.
With easy access to water, grass, nesting sites, and supplemental
food, the geese found the site irresistible, and their numbers
grew to more than 100.
Human health and safety is one concern. The potential
exists for disease transmission from goose droppings in the
water and on the ground. This is of particular concern at the
Penino Buildings child care facility which has a playground
fronting the goose habitat. Also, during the nesting season,
geese can become aggressive toward people they perceive as threats
to their eggs or goslings.
Of
particular concern to the conservation district is the environmental
impact of having too many geese in one place. Geese entering
and exiting the pond and loafing along the shore cause soil
compaction, which harms existing vegetation and inhibits new
growth. Grazing geese denude the lawns leaving bare spots
which lead to soil erosion and sedimentation of the pond and
nearby streams. Stormwater runoff carries the nutrient-rich
goose droppings into the water. Heavy concentrations of
these goose droppings in the water leads to excessive algae
growth. Decaying algae depletes the oxygen supply killing beneficial
aquatic life. Geese also drive away or kill other natural inhabitants
of the pond such as smaller waterfowl and wading birds.
The Animal Control Division of the Fairfax County Police Department,
working in partnership with the Department of Public Works and
Environmental Services, has designed a model program
that will reduce the impact of the Canada geese population on
Government Center properties in a humane, effective, and innovative
manner. Other partners in the program include Geese Peace, the
Citizens for the Preservation of Wildlife, the Park Authority,
and NVSWCD.
Since geese prefer areas where they have easy access to food,
water, and nesting site, barriers can be an effective deterrent
in discouraging resident geese.
The Herrity Building has been targeted as an egg addling
site for the past two years. Addling refers to coating the eggs
with vegetable oil within the first 10 to 14 days of being laid
to prevent them from hatching. The protocol, which requires
a permit, is endorsed by the Human Society of the United States.
In addition to slowing the growth of the resident geese population,
addling will break the instinctual bonds of geese to remain
at the Herrity Building after nesting season. When there are
no goslings, the adult and juvenile geese will be more likely
to leave the area once nuisance abatement programs begin.
Landscaping changes will include the addition of brushy
and prickly plants which create a barrier to the water source
and the use of grasses less attractive to geese (fescue, for
example). Structural measures to demonstrate alternative
shoreline treatments will include rip-rap, gabion baskets, and
biologs.
Trained
Border collies are being used to herd geese in much the
same way that they have herded farm animals for centuries. Although
the dogs never touch the geese, the geese sense the Border collie
is a predator and flee the area. The geese will attempt to return,
but the repeated presence of the dogs will convince them that
the area is unsafe. Eventually, the geese will move on to other
sites.
Finally, colorful signs will remind well-meaning passersby
that feeding geese and other wildlife is unhealthy for them,
leads to increased aggression towards humans, and is against
local regulations.
For more information about geese management, contact Earl
Hodnett, Wildlife Biologist, Animal Control Division, at 703-266-3523.
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