Geese are herbivores and have a preference for grass shoots, aquatic vegetation, seed heads, and various grains. Canada geese usually nest in March and April. Adult Canada geese have very few predators, though raccoons, skunks, fox, and crows sometimes prey on their eggs.
In general, geese have benefited from the way humans have altered the landscape. Canada geese are attracted to areas that provide food, water, and protection. Urban areas with lakes and ponds offer all the resources that geese need to survive. During the summer months, Canada geese can be a problem for some property owners. Birds often find refuge on lakes and golf course ponds, taking advantage of the lush lawns, while experiencing their annual wing molt (loss of flight feathers). Most human-goose conflict is associated with urban settings where manicured lawns are located in close proximity to water and molting geese. Geese take advantage of large agricultural fields in fall and winter.
Most complaints about geese are from residents and businesses frustrated with goose droppings. When geese concentrate at specific sites, droppings can become aesthetically unpleasant, particularly on lawns, beaches, docks, sidewalks, and golf courses. If high goose numbers persist in shallow water areas, they may even elevate bacteria levels via fecal coliform. Coupled with other contaminants, this can lead to the temporary closure of beaches. Public health agencies frequently test for levels of fecal coliform to determine if public lakes are safe for swimming.
Occasionally geese nest in inappropriate sites, such as in shrubbery near buildings or parking lots. They can demonstrate aggressive behavior toward people while defending their nesting territory.
The city has placed signage to urge people to not feed the geese and ducks. Onota Lake is still, however, home to a large number of geese and ducks, many of whom remain here year round.