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Written by Shen Mengxi
Canada Goose, as a popular down jacket brand, may be heard of by everyone. But today we are telling the story of an animal with the same name. True Canada Goose is a large wild goose native to North America, and its most recognizable feature is its color — brown neck black, black face and white chin.
Canada Goose in Flight photo/wikipedia-Daniel D'Auria
Originally a migratory bird, the goose migrates back and forth between Canada and the United States every year, thanks to its huge size (wingspan of 1.27 to 1.85 meters, weight of 2.6 to 6.5 kg), and natural aggression, they have very few natural enemies in adulthood, only coyotes, gray wolves, golden eagles, sea eagles, snow owls and a few other species. As a result, their original habitat is extremely vast, and they can be seen from northern North America all the way to areas close to Central America.
However, with the expansion of European colonists in the Americas, especially overhunting and land development in the late 19th and early 20th centuries, the Population of Canada Goose plummeted, and by the 1950s, it was even thought to be extinct. However, in 1962, American researchers found a small group of wintering geese, so they started the population recovery of Canadian geese.
In the process, because the captive-bred Canada goose could not learn the skills of migration from its parents, and because there was still an abundant food supply in the human city in winter, and there was almost no natural enemy, the Canada goose stopped migrating and became urban settlers. Their numbers in cities increased dramatically, and they soon went from rare protected animals to repulsive "pests."
Canada goose has become a settler in many North American cities Photo/wikipedia-Pierre5018
Although it sometimes preys on small insects and fish, in general Canada goose is a planted food animal, with plant leaves, grains, beans, etc. as a staple food. This habit will wreak havoc on local agriculture, especially the large-scale cultivation of wheat, corn, rice, soybeans, soybeans, soybeans, etc., which have become the delicacies of Canada goose. Of course, the major garbage cans in the city are also the fixed meals of the geese. In this way, for food, The Canada Goose not only brings losses to agriculture, but also wanders the streets, which also brings inconvenience to city dwellers.
Canada Goose in the field Photo/Oregon Department of Fish & Wildlife
In addition, the excrement of Canada goose has become a major source of pollution in those cities. Canada goose is a waterfowl that they like to be close to water – in the city, parks large and small are the perfect habitat for them. And visitors to the park are often fed, so that some of the geese can live well just by begging for food. In some urban parks in North America, hundreds of Canada geese often gather to live together. However, they are veritable dung-making machines, some foreign media described "their feces are bigger than the brain", a goose excretes a daily feces weighing 1.4 kg, simple calculation, two geese can excrete a ton of feces a year.
Foreign media are reporting on the goose dung in the streets of its city, looking at the ground of this map... Screenshot of the thestar.com web page
The problem is that the feces are randomly found in parks and city roads, and they may also carry large amounts of E. coli — Escherichia coli that blend into lakes and coastal waters, forcing many parks to limit swimming during the summer months. What's even more infuriating is that the feces left everywhere by the geese will attract the attention of dogs, and some geese will also nest next to the cisterns on the roofs of some buildings, which greatly increases the risk of E. coli infection in humans.
Canada Goose on the beach in a state park in New York State photo/wikipedia-Geoffrey.landis
In addition, there are also geese that cross roads or settle near airports, posing a huge risk to public transportation. In 2009, American Airlines Flight 1549 was forced to land on the Hudson River after colliding with a group of Canada geese, which was later adapted into the famous movie "Captain Sully".
Flight 1549, which landed on the Hudson River, photo/wikipedia-Greg L
As a result, since the 1980s, major Cities in North America have been looking for ways to drive Canada goose. The simplest way to drive away is to use scarecrows or owls, crocodiles, etc. Models, although people complain that the feces of Canada goose are larger than brains, which does not mean that they are not good at brains, and after a while they become accustomed to these methods, so this method soon fails.
Of course, it is easier to think of as a way to hunt Canada goose, and many American and Canadian companies choose to do so, but this is very limited, on the one hand, the legal protection of Canada goose, hunting requires the application for hunting permission, and can only be carried out at a specific time and within a specific time; on the other hand, the hunting will be greatly resisted, and the habitat after hunting will still attract a large number of Canada goose in the second year, so this is not a good approach.
After the city of Denver shot 2,000 Canada goose in 2019, demonstrators marched in front of the city hall to protest Photo/Screenshot of the Denver Post webpage
To solve this problem, parks in the United States and Canada have come up with some comprehensive means. The first is to remodel habitats to make city parks look like Canada geese don't like. For example, reducing the area of the lawn, increasing the density of shrubs or branches on the lawn (which can limit the take-off of geese, they do not like this environment), etc., while transforming the urban suburban environment into an environment that the geese like, attracting geese to the suburbs.
The second is to drive, if the number of geese increases to a certain threshold, it will begin to drive, the means of expulsion are various, with lasers, with sheepdogs, and with drones, but some geese have learned to be obedient, they will fly away at the time of driving, and then soon they will fly back! And if it happens to coincide with the breeding season, the Canada goose leading the young goose will have a bad temper, be irritable and aggressive, and it is easy for people and dogs to break their heads and bleed.
The last method is to do family planning for the geese! Originally, park managers thought of taking the eggs straight out of the nest, but the goose's habits are the same as chickens, take one out, it will lay one, or even more eggs, so later people's technology was updated a little, take out the eggs, kill the eggs, and put them back. This method is simple and easy, using a needle to break the eggshell, or applying grease to the eggshell (which insulates the air), or just shaking hard can prevent the egg from hatching. But the geese don't know, so they will continue to hatch these dead eggs.
Canada's goose nests are very common in some cities in North America photo/wikipedia-Famartin
But the disadvantage of these approaches is that they cannot be done once and for all and must be done year after year. We once brought them into danger of extinction, and now when their numbers are restored, we have to start to control their numbers, and there is still a long way to go in harmony between man and nature.
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