Thursday, April 20, 2006

Living with Geese



It’s spring, and that means teams of specially trained municipal workers and volunteers are tramping around wetlands, golf courses, sumps, land fills, and even shopping malls armed with umbrellas, buckets, and vegetable oil. The teams are searching for geese that are nesting in areas that interfere with human activity and that are unsafe for the birds.

Like the goose at left, which is incubating her eggs in a planter on a dock, geese are increasingtly nesting in inappropriate places throughout Long Island and the entire eastern seaboard.

Each time a nest with at least one goose egg is located, the umbrella is used to shoo away the parents. The bucket is filled with water, and the egg is placed in the bucket. If the egg sinks, the embryo has not started to develop. In such cases, the egg is oiled to prevent oxygen diffusion. Cutting off the oxygen supply prevents the development of the embryo. Thus, a chick will not hatch. The egg is then placed back in nest so that the parents will not lay another egg to replace it—and population growth is reduced by one.

Eggs found in nests located in good nesting habitats also are oiled in order to limit popultaion growth as much as possible.

The effort is part of GeesePeace, a humane geese control program adopted by the Town of Oyster Bay, the Town of North Hempstead, and some villages. The program also involves site aversion. After the chicks hatch and before the birds molt (lose their feathers and are temporarily unable to fly), specially trained dogs (usually border collies) are used to systematically heard the birds away from inappropriate locations.

What you can do

It is important not to feed geese. Feeding geese is bad for the birds. Grasses and other plants are the natural diet of geese. A diet of bread and other human foods causes vitamin deficiency and makes geese vulnerable to serious, debilitating avian diseases. Feeding geese also encourages the geese to remain in an area and attracts more geese to the vicinity. This undermines the humane goose control management policies of local municipalities.

How geese affect water quality

For thousands of years, flocks of Canada geese have migrated across Long Island twice a year, in the Fall en-route to southern wintering grounds and in the Spring en-route to northern nesting grounds.

But, in recent years, flocks of resident, non-migratory Canada geese have grown so large that they have become a serious nuisance, a health threat, and a source of pollution. Runoff from geese waste drains into streams and storm drains and enters waterways, where it contributes to pollution. Geese waste also causes problems on golf courses, playgrounds, and ball fields.

The geese causing these problems were introduced to Long Island and neighboring states several decades ago for hunting and conservation purposes. The swelling population of these non-migratory geese—and the problems associated with them—were not anticipated.

Wonder birds

Geese are intelligent, excellent parents. They stay together all year and mate for life but will find a new partner if a mate dies. Migratory geese mate and nest in Canada. Only resident geese that were born in the United States mate and nest in the United States.

Migration is a learned process. Migratory geese return to the general area of their birth each year to mate and nest. Sometimes they nest in the exact same location from year to year, sometimes they choose a location nearby. Migratory geese do not become resident geese unless they are injured.

The flight range of migratory geese is 2,000- to- 3,000 miles. In contrast, resident geese fly 100- to- 200 miles to find food, water, and safety. Resident geese could fly as long a distance as their migratory cousins, but they have learned that long flights are not necessary.

Nesting

Nesting season is from mid-March to mid-May. Geese begin to nest at age three. They prefer isolated sites near water. Islands are their favorite location. Nests are usually on the ground. When egg laying begins the male partner, known as the sentinel goose, stands watch nearby—but not close enough to give away the location of the nest to a predator. When a solitary goose is seen during nesting season, it’s probably the sentinel goose—and a nest probably is somewhere in the vicinity.

The group of eggs laid by the female is called a clutch. She generally lays 1 egg every 24 hours for several days until a full clutch is established (5 eggs on average). When all the eggs are laid, she begins to incubate them. Thus, all the hatchlings are the same age when the hatch. The incubation period is 28- to- 30 days.

It is easy to tell if the embryos have started to develop. Eggs not being incubated are cool to the touch. Undeveloped eggs that are still fluid sink or float vertically with the wider portion of the egg pointing down. Developing eggs float horizontally or at a slight angle and break the surface of the water.
At that point the goslings are 1- to- 2 weeks away from hatching.

All geese eggs in a single clutch hatch on approximately the same day. Baby geese are called goslings. They can fly approximately 2- to- 3 months after hatching. Geese can live up to 20 years and usually weight 20- to- 30 pounds.

When geese are chased from a traditional nesting area or a nesting area with too many nesting pairs, they find alternative sites to nest. These sites are often quite marginal—too far away from water and food—and may be in highly inappropriate locations—such as rooftops, balconies, ball fields, golf courses, and parks.

Molting

Each June, adult geese lose their wing feathers, a process called molting, and are temporarily unable to fly. Molting season runs from early June to late July. During the molt, geese need to be near water for easy escape from predators, and a food supply must be accessible. Foxes, raccoons, owls and snapping turtles are the natural predators of geese. Geese can fly again approximately 6 weeks after molting. Generally, by early August all geese (except those that are injured) are ready for flight.

Photo by Jennifer Wilson-Pines
GeesePeace Coordinator

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