Learning to pick our battles is an important life skill, but a Canada goose in Banff might have skipped that lesson.
Banff resident Lawrence Carter was paddling on the Bow River in Banff National Park last week when he saw something odd: a Canada goose perched at the top of a tree.
Most Canadians are used to seeing Canada geese roaming parking lots or loafing around in parks. But a goose in a tree isn’t something we see every day.
Why was our feathered friend in a tree to begin with? Apparently, she was taking advantage of her squatter’s rights by taking up residence in a vacant osprey nest!
“The second day, the osprey arrived back and harassed her for a while, but when she put up a fuss and didn’t seem inclined to move on, they abandoned the nest to the squatter,” Carter told the Rocky Mountain Outlook.
It has been about two weeks since Carter first spotted the adventurous Canada goose, but he’s worried the animal may not have thought its decision through.
“How is she eating? If there is an egg, what’s the plan when it hatches? Goose babies are in the water long before they can fly, and she’s a long way up,” said Carter.
Carter’s questions and concerns are valid. However, Jason Rogers, an independent biologist and editor for eBird, claims there might be a method behind the goose’s madness.
Perch Perfect
Canada geese tend to nest on the ground in slightly elevated areas near water, such as muskrat mounds or beaver ponds.
Waterside nests are ideal because soon after goslings hatch, the young geese are led to water, where they learn to swim and forage.
You might be wondering how goslings are supposed to leave a nest that is high up in a tree.
According to Rogers, goslings are small but durable, capable of surviving falls from great heights.
Geese aren’t afraid to take advantage of artificial habitats like golf courses, airports, parks, and other areas with lots of grass and unobstructed views.
Having a good view of the surrounding area plays an important role in deciding where a goose nests because it allows the animal to watch for approaching predators.
A Canada goose nest is made of dry grasses, lichens, mosses and other plant material. Osprey nests are similar and are made using sod, grasses, vines, algae, and bark.
Female geese are responsible for selecting the nest site, building the nest, and incubating the eggs, while the male guards the nest.
Mother geese are incredibly busy, and osprey nests share similarities with goose nests. Can we blame the Canada goose in Banff for taking advantage of an empty nest? She’s working smarter, not harder!
“Nesting in trees is something that likely serves them well in areas that are, for example, subject to early spring flooding or where ground nests are at a heightened risk of predation,” said Rogers.
A Conflict Of Nesting
Was the osprey’s nest truly abandoned? If it was, why would an osprey attack the Canada goose?
Canada geese begin nesting from the middle of March through late April. Meanwhile, ospreys usually start nesting around late April through June.
Canada geese and ospreys’ nesting times are very close to each other, which can lead to conflict when a goose occupies a vacant osprey nest.
Both animals tend to return to the same nesting site every year. So why didn’t the Canada goose in Banff return to its own nest?
Most Canada geese do not breed until their fourth year. This may be her first breeding season or her first time choosing a nesting site.
On the other hand, the goose’s nest may have been destroyed or she decided the area was no longer suitable or safe for nesting due to predators, environment, or other issues.
Whatever the reason, the Canada goose was still in the nest when the osprey returned, leading the osprey to attack the goose.
However, geese aren’t nicknamed “cobra chickens” for nothing. The goose stood its ground and was unbothered by the ospreys’ attacks.
What might seem like a harmless and funny interaction has an impact on osprey breeding.
Birds Of A Feather
The goose in Banff isn’t the first of its kind to evict an osprey from its nest. In 2021, a Canada goose was spotted perched in an osprey nest above Highway 97 near Vernon, British Columbia.
According to Vernon resident Alister James McLellan, it was the second time the Canada goose had hijacked the osprey’s nest.
According to Rogers, when Canadian geese take over an osprey’s nest before it returns in the spring, it often disrupts the osprey’s breeding for the season.
A pair of ospreys whose nest is occupied is faced with two choices. Wait a couple of weeks for the goose and its goslings to leave the nest, or build a new nest. Both options are incredibly time-consuming.
“A delay may mean that the ospreys can’t raise as many young, so they may attempt to evict geese from their nests by diving at them. This is sometimes successful, but the geese usually win the battle,” said Rogers.
In some cases, displaced ospreys choose to skip breeding entirely for the year or reclaim their nests when it’s too late in the season to breed.
Thankfully, Canada geese and ospreys aren’t at risk of becoming endangered species anytime soon. The population of Canada geese has increased by almost ten percent between 1966 and 2019.
According to the Partners in Flight Database, the global population of Canada geese is estimated to be over seven million.
Almost three million Canada geese have been killed by hunters yearly in North America, which has had no noticeable effect on their population.
The story of ospreys is a bit different from that of the Canada goose. In the early 1950s and 1970s, pesticides poisoned the birds and thinned their eggshells, causing increased mortality.
However, thanks to conservation efforts, the global osprey population has rebounded to over one million, and the birds are now classified as a species of low conservation concern.
For the osprey in question, it will likely need to find a new home; just another victim of Banff’s ongoing housing crisis.
