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Living In Harmony with Wildlife: Canadian Geese

Canadian geese are a large impressive bird when you take a close look at them. They mate for life and are attentive, protective parents as you may have noticed if you've ever gotten too close. They even use the nanny system. I will admit I do love when the hatchlings arrive. But those adorable little baby fuzzies grow into lots of big adults. Like many species that were once at risk of extinction due to human impact, we did too good of a job of bringing their populations back up. Now looked upon as a nuisance species, Canadian geese cause many problems in many different ways. We are still doing them harm as well, mostly without realizing it while having good intentions.

As a stormwater inspector I encounter Canadian geese and their aftermath on a regular basis. When a new building project increases the amout of hard, impervious surface on a property they need to install a stormwater feature that will account for the stormwater runoff that will occur as a result. This includes individual buildings and subdivisions of residential homes. These features, such as retention and detention basins/ponds, create an ideal habitat for the geese. As a result we end up with a landscape that has turned into a mine field of goose scat/feces, bare patches of grass, and large flocks of large angry birds if you get too close. In order to inspect these basins I have to navigate the mine fields and angry birds. More often than not they move away when they see me, but there are occassions when they stand their ground and start hissing. I know to give them a wide berth because they will attack and bite.

Along with the sight of sidewalks and greenspace full of poo, their feces can also spread diseases and parasites such as salmonella, listeria, E.coli, taxoplasmosis. It also causes these bodies of water to become eutrophic, meaning that the increased nutrients in the water due to the feces results in an increase in algae which takes away oxygen and kills organisms in the pond. The algae can also clog the water quality orifices in the outlet structures of the basins.

Then there's the harm that we do to them and other water fowl. I would wager to say that almost all of us have done it. We go to a park or beach and feed the birds bread, crackers, chips, etc. It gives us and the little ones encounters with wildlife which is a good thing to a point. We think we're helping them by giving them an easy meal, but we couldn't be more wrong. There are reasons that parks have started posting signs not to feed the wildlife. We think we are helping, especially in winter (many Canadian geese are residential, not migratory), but we are doing more harm than good. Bread and other snack foods are not what geese eat in the wild, it is not their natural food source and they are not designed to digest it. This can lead to malnutrition, deformities, and death. Think about it, what would happen to you if all you did was fill up on junk food? You wouldn't have room to fill up on the stuff that's good for you and you'd feel pretty crappy too and be more likely to get sick. If you always hand-fed your babies empty carbs, would they know how to get nutritious food on their own? Would their brains and bones develop properly? One of the common deformities seen in waterfowl due to malnuitrition is called "angel wing". This is a deformation of their wings that renders them flightless. This is not curable, unless caught early in youngsters, and it significantly reduces their chances of survival in the wild. In addition to dependency, hand-feeding also leads to the geese becoming less fearful fo humans which leads to aggressive birds that expect us to feed them.

So, what do we do? How do we live in harmony with these birds? As with most wildlife species, this usually entails using a variety of tactics.

  • Engineering and designing stormwater ponds to be less attractive using a combination of techniques. Play on their fear of predators and their laziness by using 2:1 slopes, armoring slopes with large rocks (rip rap), and high vegetation. These make it difficult for them to walk to the water and hides predators. These also result in increased biodiversity around the ponds.
  • Scare tactics such as predator decoys, noise, dogs, green lasers, and drones.
  • Repellants and bitterants on food sources.
  • Population management techniques such as nest disturbance (egg addling) and hunting.
  • Do not feed them. If you insist on feeding them give them foods that are more nutrious, such as peas, oats, corn, kale, etc.

Please note that it can take years to lower a very large, established population of Canadian geese.

The actions we take, whether destructive or beneficial affects something else, it has a domino affect. All living creatures are connected and have a role to play in the survival of our planet.

Blog Author: Kelly Parker, Stormwater Specialist

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