On Vancouver Island and surrounding islands in the Salish Sea, an overabundance of geese are damaging sensitive estuaries that took millennia to develop. Canada Geese love Carex lyngbyei, commonly known as Lyngbye’s sedge, so much they will eat it right down to the rhizomes.
“They go into the estuaries and they muddle with their feet, which loosens up all the beds and then they pick out all the rhizomes,” says Cory Frank. This exposes the thick marsh platform to erosion.
Cory and Randy Frank of K’omoks First Nation are brothers who grew up being close to the land, following rivers and waters’ edges. They still are – now as K’omoks Guardian Watchmen.
They protect and monitor the abundance of life and systems in K’omoks territory. It’s a land of tall forests, fast and slow waters, mountains and valleys. They guard against threats to habitat and ecosystems – and this includes geese.
The erosion of habitat caused by geese triggers a series of impacts to a variety of species, say the estuary guardians.
The K’omoks Guardian Watchmen have been working on the geese issue for five years. Their focus has been on restoration of habitat, and harvesting geese as food for their community.
“As Guardians of our traditional lands, we not only protect but we also make efforts in restoring our lands for our future generations,” says Cory Frank, leader of the Guardian Watchmen Department for K’omoks First Nation.
The rhizomes of carex lyngbyei do more than feed their sedge. They build up over time, forming thick mats – interwoven, catching sediment and composting leaves until they are the marsh platform itself. Through the geese focusing on this plant, eventually the estuary’s platform is destroyed. The overgrazing and “grubbing” for the roots and rhizomes also happens along channel edges. The channel edges are particularly sensitive; channels are key to how the estuary regulates flooding.
Built up over millennia, this platform and edges have washed away in many areas, channels have become shallow, and productive habitats have been reduced to gravel.
Guardians of Mid-Island Estuaries Society (GoMIES) looked at old air photos and vegetation baseline surveys from before resident geese were introduced, and compared what sedge marsh habitat remains at several estuaries. At the Englishman River Estuary, over 98% of sedge marsh habitat was lost. At the Nanaimo, K’omoks, and Campbell River estuaries, GoMIES estimated over 90% was lost or severely degraded.
This is habitat that many species rely on, including salmon fry. The fry use estuary marshes all along the east coast of Vancouver Island as protection and rich places for food in their early growing stages. Estuaries are used by 80% of coastal fish and wildlife, according to GoMIES. They also function as an ecosystem’s natural flood control, water filtration, and carbon sequestration.
92% increase in geese, say stewards
Until the 1960s, Canada geese were migratory visitors in BC. This changed when wildlife and game agencies introduced eggs to increase hunting opportunities.
In 1979, a Canada Goose Management Plan from BC’s Ministry of Environment described the intention to increase BC’s breeding population from 25,000 to 40,000. The idea was to provide a larger population for sport-hunting days and an annual sustained harvest of 20,000 birds.
A few factors weren’t taken into consideration, says Tim Clermont. Clermont works with Guardians of Mid-Island Estuaries Society.
Some of the areas favoured by geese have grown into areas of increased human population development – especially waterfront development. This, along with changes in food systems and the average diet, resulted in less hunting.
In a correlating timespan, the number of active waterfowl hunters in this zone has dramatically declined since the 1970s, GoMIES cites from Canada Wildlife Service’s National Wildlife Research Centre.
With change comes adaptation, and Canada geese happen to be particularly well suited to adapting to human habitation, says Clermont. Parks, school grounds, and farmers’ fields are all additional places the geese have adapted to as habitat, says Clermont.
Although migration may happen for some populations, with these populations there is a stronger instinct of site fidelity, says Clermont. This means geese will return to the nest site they were born in. Migration may be a learned instinct, suggests Clermont. These particular populations have a distinct non-migratory behaviour.
Cory Frank agrees, noting these eggs were introduced without parents to imprint upon.
“It’s a non-migratory species that has developed because of the wildlife service and other government agencies that have brought eggs here in the past to create better hunting areas for hunters, but they did not bring adults to instill migrating instinct,” says Frank.
Humans introducing a species has adversely impacted biodiversity in the estuaries, and it will take a concerted effort and multiple approaches to correct the error.
In K’omoks territory, the focus is on restoring habitat and managing the numbers through egg addling and harvesting.
Habitat restoration works in the Kus-kus-sum estuary include transplanting and planting plugs of carex lyngbyei to reclaim marsh platforms.
“As a species, those [sedge] grasses are highly important. If you looked out at Parksville, some of the areas where they were wiped out, they also lost a lot of the small birds, like the red-winged blackbirds, and other small birds, when all those grasses were gone – it was almost dead. Now that the grasses have come back, you see all these species of birds back in there again,” says Randy Frank.
Eco-cultural habitat exclosures (barriers made of alder and willow) are installed in estuaries to prevent geese from entering and overgrazing carex lyngbyei. Alder stakes are interwoven with willow, similar to traditional fish traps in structure and presence.
“It breaks down, out there in the field it’s natural and then we just replace it … it’s very cost-effective and it looks a lot better than metal rebar and plastic orange snow fencing,” says Cory Frank.
The geese avoid the exclosures, as it prevents them from landing or taking flight.
“Geese aren’t like ducks, who can helicopter in and out. They need longer flight ways, and so the exclusion barriers work very well to keep the geese out of replanted areas,” says Clermont.
Population management to date hasn’t found a quick fix, as outlined in GoMIES Canada Geese management strategy. The natural adaptation of the geese to their situation requires a coordinated action of both egg sterilization and harvesting.
Egg sterilization is done through “egg addling,” first initiated on East Vancouver Island to protect Cowichan estuary and farmland hot spots in 1999. Addling is effective to reduce juvenile recruitment to local populations. Eggs are located, shaken, and left in the nests during a very specific window of time. The addling starts two weeks after eggs are laid, starting late March to mid-May.
“Over 300 nests were located in 2020 and we expect to exceed 400 nests in 2021 at over 40 sites including Conservation Lands owned by the Nature Trust of BC, private farms, 12 Gulf Islands, and lands managed as National Wildlife Areas or Migratory Bird Sanctuaries. Over 2000 eggs will be addled this spring and our group of professional volunteers and contractors have addled over 15,000 eggs over the past two decades,” says Clermont. Prior to the mid-1980s no Canada Geese nested in any of these sites.
Addling is an established population control program that can work, says Clermont, as it lowers re-nesting rates. It does depend on consistency, requires crews, and the geese do find ways around it. Failed nesters may nest or re-nest in more remote or isolated areas.
Community food security
There’s a wisdom in project management, to seeing the opportunity as well as the threat. This is where the harvesting comes in.
The Frank brothers had an eye for providing food early, says Frank. They have good memories of being out on the land with their parents. As they grew, they’d come home with fish for their mom.
Today their skill in harvesting is addressing the overpopulation of geese by meeting food security goals for community members.
Local families including members of K’omoks First Nation have benefitted from the food source. K’omoks guardians have also worked alongside, and trained, members of Wei Wai Kum, Snaw-Naw-As, Tsawout, Tsartlip, and Tla’amin.
Frank has high praise for his team, and appreciates GoMIES involving them.
“It is a great program to be involved with, for making connections with all the other partners that we work with,” says Frank.
Knowing it will take persistent and multiple approaches to restore balance to their ecosystem, K’omoks guardians will continue to work toward returning biodiversity and functioning ecosystems on their lands.
Odette Auger, Sagamok Anishnawbek, is a guest on Klahoose, Homalco, Tla’amin territories. She works with IndigenEYEZ, has written and produced for First People’s Cultural Council and Cortes Radio. Her journalism can be found at Watershed Sentinel, IndigiNews, the Discourse, APTN, and the Toronto Star, among other places.