Bowen’s Canada geese are relative newcomers to the west coast, and they have a different history than the flocks of Canada geese we see high overhead on spring and fall migration. Our resident geese are the products of a 1970s experiment aimed to provide hunting opportunities and enhance wildlife viewing and by intentionally introducing juvenile Canada geese from eastern Canada to Metro Vancouver. The plan was that hunters would check goose population growth.
The geese headed to urban areas where they found few predators. Municipal restrictions on firearm discharge ruled out hunting. Lacking a goose family to teach them the traditional migratory habit (and with fine edibles close to hand) the newcomers had no reason to move on. Vancouver’s wild migratory geese became urban residential geese and expanded their territory to include Bowen Island.
The newcomers liked the plentiful food in their new home. Lawns, parks, and golf courses offered grazing opportunities through winter months, a time when wild pickings can be lean.
Bowen’s Canada geese have chosen to live among Deep Bay’s finest waterfront real estate. Acres of mowed, grassy lawns provide an endless supply of tender, young, shoots to feast on. The Cove has clear sightlines and easy access to water for a quick escape. Dense human occupation discourages most predators. Frequent handouts of food are an attractive bonus.
Canada geese pair up by their third year; mate for life; lay an average of five eggs each spring; and can live in the wild for over 20 years. Each summer, adult geese shed their feathers to make way for new growth. During the moult, both adults and young depend on food resources within walking distance of the breeding area.
The Canada goose’s habit of mixing gosling from several families into large groups (super broods) under the care of a few sentinel adults provides both safety to goslings and an advantage to adults. Researchers believe eagles, ravens, and crows, who commonly prey on goslings, find an individual gosling in a tightly moving group harder to pick off one isolated young bird.
Large families may provide benefits for goslings and parents alike. Large goose families tend to dominate smaller families during social interactions; super broods secure access to the best food so their goslings grow faster.
With a year-round supply of food, and very few predators, Bowen’s population of Canada geese appears to grow every year. Large groups displace other native waterfowl, reducing the availability of food, shelter, and nesting sites. Canada geese frequently overgraze natural habitats, particularly along fresh and brackish water shorelines, which directly reduces plant species diversity. Vegetation loss along shorelines results in increased erosion and sedimentation of water bodies, as soil and other particulates are suspended in the water column.
The humane way to limit flock growth and stabilize goose populations is to keep eggs from hatching by treating them with corn oil, a process known as “addling.” Addling can be done only with a permit from the Canadian Wildlife Service.
When you see a flock of geese grazing, give them space. Under the BC Wildlife Act it is illegal to harass wildlife. Unleashed dogs must not be allowed near geese. Something we can all do is to NOT offer food to the geese. Supplemental feeding by humans can contribute to geese being able to lay more than one clutch per season. Managing growing populations of non-migrating Canada goose is a challenge.