Giant Canada Goose Facts
Although Missouri may host several sub-species of Canada geese in the course of each year, the giant Canada goose (Branta canadenis maxima), is the one that causes the most problems for homeowners.
Once thought extinct, these geese have made a phenomenal recovery. Presently, their numbers are approximately 3.5 million birds in the United States. In Missouri, the breeding population has ranged from 50,000 to 75,000 during recent years.
Although most people enjoy having Canada geese around, they cause hundreds of thousands of dollars in damage each year. Problems include:
- accumulation of droppings on lawns, ball fields, golf courses and sidewalks
- erosion on lawns and golf greens when geese overgraze the area
- personal injuries from attacks when geese defend their nests
- threats to aviation safety and aircraft
- destruction of newly sprouted field crops.
Damage caused by geese in Missouri has become significant, requiring new management strategies by state and federal agencies to provide assistance in resolving the problems. Although Canada geese are protected by state and federal laws, many effective control methods can be used to minimize or eliminate damage.
Note: Some methods, such as egg oiling and addling, require permits, but many do not. If a permit is needed, see page 23 for information on how to apply.
Although most people enjoy having giant Canada geese around, these waterfowl
can cause hundreds of thousands of dollars in damage each year.
Ed Hartin photo
Goose with Chicks
General Biology
The average adult giant Canada goose weighs 11 to 12 1/2 pounds, but some reach as much as 16 pounds. They have a wingspan of approximately 6 feet, making them one of the largest flying birds in Missouri. Giant Canada geese generally winter close to their breeding grounds as compared to other subspecies of Canada geese that migrate between nesting and wintering grounds.
Giant Canada geese may become sexually mature as early as 2 years of age, while other subspecies mature at 3 or 4. They generally mate for life with a single partner, but will find another if the first one dies.
In Missouri, geese begin establishing nesting territories as early as February where they remain throughout the nesting season, which lasts into May. Usually, they establish nests on islands or near water, but occasionally choose rooftops, parking lot islands and large plant pots near building entrances, where they can become a hazard or a nuisance. Each pair produces a single clutch of eggs during the season, but if the nest is destroyed early in incubation, they may produce a second.
Generally, a female Canada goose lays one egg every 1 to 1 1/2 days until she has a full clutch of 5 to 6 eggs. She remains on the nest for 28 days. The adult geese lead their young to a lake or pond within two days of hatching.
Young Canada geese grow quickly and can usually fly within 70 days of hatching. They imprint on the area where they learn to fly, and are likely to return there to produce young of their own.
Approximately one third of the young survive to adulthood. In urban areas, where they are protected from predators and hunting, their survival rate is likely to be higher. Geese sometimes live for 20 years or more.
Canada geese are primarily grazers, feeding on grass and crops. During the summer months when most damage occurs, they are attracted to the succulent new shoots of grass growing on lawns and golf courses, as well as to sprouting crops.
Fecal contamination is the most common Canada goose damage complaint in Missouri. Some studies have shown that geese can leave droppings every seven minutes while feeding. In addition to the unsightly aspects of fecal matter on public walkways and in children's play areas, the accumulation of feces may cause increased levels of fecal coliform bacteria in the water, which could result in closure of public swimming areas.
Canada geese are attracted to areas that have sources of food and water. They prefer bodies of water that have gentle sloping shorelines with manicured lawns as this habitat provides easy access to food and offers quick escape from predators. The area becomes even more attractive if other waterfowl are present.
Another major attractant is people who feed geese, thus providing an artificial food supply that concentrates the geese in unnatural numbers. Well-meaning, but misguided people typically feed bread, which does not provide geese with the proper nutrients they require. This artificial feeding, if not supplied regularly, may cause the birds to inflict greater damage to vegetation and ornamental plants.When large numbers of geese congregate due to artificial feeding, diseases such as avian botulism or avian cholera can develop and could potentially effect the entire local goose population.
Legal Status
The Migratory Bird Treaty Act (16 USC 703-711) protects Canada geese, their nests and eggs. This federal law prohibits capturing or killing Canada geese outside of legal hunting seasons. Presently, the U.S. Fish and Wildlife Service allows the Missouri Department of Conservation to issue permits to property owners to help control nuisance geese.
Most permits are issued to oil and addle eggs; but in some cases, kill permits may be given to landowners suffering damage. At qualifying sites, communities are issued permits for goose roundups; and the meat is processed and donated to food pantries.
