The sewage settling ponds on Iona Island provide a quiet home with lots of food for birds. The irony that wastewater treatment plants have become nutrient-rich, low-disturbance habitats for a wide variety of low-nesting birds is not lost on local bird scientists.
Catherine Jardine, ornithologist and data analyst with Bird Studies Canada, is hopeful as Metro Vancouver starts planning its $1.9 billion rebuild of the Iona Island Wastewater Treatment Plant that they will take into account the rich avian population and the importance of the area for local birders and scientists collecting data on birds.
Jardine said Iona Island was the first place she herself came to look for birds when she got her own set of wheels.
“This is the premier birding spot in the Lower Mainland and it’s beside two major cities,” Jardine said. “There’s such a benefit (…) from a tourism perspective, connecting-to-nature perspective and a research perspective.”
The Fraser Estuary, including Iona Island, supports millions of birds during their annual migration. According to ebird.org, Iona Island has the largest number of identified bird species— 286 bird species have been spotted there, the most overall in British Columbia.
James Casey, program manager with Bird Studies Canada, pointed out the diversity of the Iona Island habitat with lagoons, cottonwoods, an intertidal habitat and sand dunes that attracts different types of birds to the area, and the infrastructure in place — the causeway, trails, the sewage pipe — allow people to see the birds.
“The fact that we’re up on the pipeline looking down on a pond and people walking on the causeway there looking into the pond — the nice wooded trails, that’s all infrastructure that was not necessarily planned but valuable in providing that opportunity to get close to the birds,” Casey said during a recent walk around the lagoons where, despite being January, one could see red-winged blackbirds, Phanini great blue herons, flickers, pied-billed grebes, a coot, scops, buffleheads, bald eagles, the ubiquitous crow, gulls and several duck species including the northern pintail, American widgeons, mallards and shovelers.
Rare species show up on Iona Island every once in a while, with a story of a spoon-billed sandpiper in the 1980s being one of the most renowned, but, more recently, cave swallows made an appearance to the delight of many birders.
Jerry McFetridge was in the Lower Mainland for a meeting from his home in Quesnel and he had taken time out to come to Iona Island to spot a few birds.
“Iona is the top place for birds — for water birds, marsh birds,” he said, sporting a long-lensed camera on the cool and cloudy January morning, ready to capture photos of the wintering birds.
Since the 1990s, researchers and amateurs have been collecting data on Iona Island for the B.C. Coastal Waterbird Survey. It’s challenging to collect data on coastal birds in their inaccessible summer habitats in northern B.C. so places like Iona Island are better suited to counting these birds.
“We think of birds as flying south for the winter, but in this area of the Salish Sea and the coast, we are south,” Jardine said. “So, a lot of those ducks that you see (on Iona Island), those coastal waterbirds, they are spending their winters here – they’ve come from farther north.”
This first scientific study of coastal birds, which was conducted between 1999 and 2011, showed 22 species in decline, including several that frequent Iona Island, for example, the green-winged teal that declined by 7.9 per cent over the 12-year study period. As the study is coming to its 20th-anniversary date, new numbers will be released on the number of coastal birds.
In anticipation of the wastewater plant rebuild, Metro Vancouver is planning to decommission the lagoons and build a dewatering facility.
Jardine said, while the lagoons are currently a great place for birds, other options for the area that might work include an inter-tidal salt marsh or restoration of the dune habitat that used to be there.
Casey said they were submitting feedback to Metro Vancouver in late January asking for maintenance of ponds and places to view birds as well as for some kind of investment, for example, a research facility, birding platforms and ecotourism and educational opportunities. Bird Studies Canada wants Metro Vancouver to see the importance of the Fraser estuary as a stopover for birds, he added.
Researchers with WildResearch have almost a decade-long dataset of the songbird population from Iona Island, with baseline data on spring and fall migration, done at the Iona Island Bird Observatory. With two universities close by, Jardine said linking public outreach with research projects is a “nice model” to allow the public to see the birds and then learn about the research being done.
Another aspect in the ongoing shoreline work is addressing rising sea levels, which is expected to be between one metre and 1.2 metres over the next 50 years.
With higher water levels at the foreshore, the mudflats, currently feeding grounds for large number of bird during low tide, could be lost.
“That’s really key bird habitat for the foraging species here and for stopover habitat for the entire Pacific population of dunlin, for 70 per cent of the world’s western sandpipers,” Jardine said. “(The mudflats are) important because of the numbers of species that it supports with it.”
If there is only a dike and the sea level rises, not only will the foreshore habitat be lost, but also the salt marsh and the dune habitat will be, too, Jardine pointed out.
“Understanding that sea level component is going to be a big part of what the habitat is going to look like,” she added.
Casey said Bird Studies Canada is part of on-going dialogues about climate change adaptations around the estuary of Richmond, Surrey, Delta and Vancouver.
“If you look at the maps and see the possible flooding associated with one metre, you’re looking back up the river in terms of where the new interface between fresh water and marine water is going to be,” Casey said.
There will be a complete rebuild of the Iona Island Wastewater Treatment Plant, which will upgrade the facility from a primary to a secondary treatment facility at a cost of $1.9 billion, scheduled to be done by 2030.
