ASK A SCIENTIST
Question: Why are some Geese still in Binghamton this time of year?
Answer: Observing the number of Canada Geese in many of our suburban environments, it's hard to believe that over hunting pushed these birds to the brink of extinction in the lower 48 states. The Migratory Bird Treaty Act was created, partially, to protect remaining Canada Geese. In New York and many other states, the recovery of goose populations includes the rise of resident goose populations; geese that stay later every winter or don't migrate at all.
The origin and, even the definition, of 'resident' Canada Geese has been a source of debate; especially since there are many recognized races of Canada Geese. The total number of races has not been completely agreed upon (so far, there are officially 11.) Some 'resident' geese are really from migrating populations for which New York is the wintering grounds. The common origin seems to be something like this: After geese were thought extinct (or close enough), small populations were discovered and federal, state, and conservation agencies began programs of reintroduction. Various methods were used to increase goose numbers such as incubating eggs in captivity, releasing game farm geese, and relocation of members of existing groups. The geese were reintroduced to areas where there used to be natural populations and possibly introduced to places where geese hadn't been previously. The reintroduced geese might have primarily been resident geese in the first place and we've helped them expand their range.
No matter the origin of resident geese, the increasing numbers have a very distinct cause. Whereas many species are losing habitat to humans, Canada Goose habitat is increasing due to climate change, human caused changes to the landscape, and lack of predators. Our winters are becoming milder which allows more geese to survive over wintering in New York. Agricultural fields provide food; athletic fields, mowed lawns, and parks provide food and roosting habitat. People love to mow grass into vast expanses right down to ponds, rivers, and other bodies of water. Canada Geese love mowed grass, too, especially with easy access to water. Non-native, turf grass in parks, golf courses, and some cemeteries provide constant new, tender grass shoots for food and a large viewable area to watch for predators. Predators, such as snapping turtles, coyotes, and raccoons, that may reduce goose populations are often removed, driven away, or find easier meals in our garbage. All these factors lead to more geese close to or in urban/suburban areas.
Resident Canada Geese have become a source for controversy in some areas making it hard to get accurate information. Some love the presence of geese whereas others see them as pests. The truth is, we create the habitat and conditions for animals to become pests by taking away natural habitat, altering habitat and destroying or altering the behavior of predators.
The problems related to geese depend on where they are and what people will tolerate. Some geese can be aggressive during nesting season. Geese can produce a lot of droppings which itself is often a source of controversy and misinformation. Canada Geese breeding near airports are certainly a concern as goose and airplane collisions do happen.
The best solution is for communities to become informed. How effective are various forms of control and are they needed? Are people more likely to get sick or have reactions to goose droppings or the chemicals on lawns and athletic fields? Are bacteria found in waterways from geese or from runoff of human and agricultural waste? Do high numbers of geese lower water quality for other species in some bodies of water? Communities should decide together what the best course of action is; whether it is goose population control, changing behavior (goose or people), or changing habitat conditions.
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