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Rock Elm just discovered at Voyageur Provincial Park and the largest known individual tree on public property and in natural conditions. Photo: Owen Clarkin.

Mapping Ottawa’s biodiversity, one weekend at a time

By Susan Johnston on September 23, 2020

“We’re at a very ground-level stage here where we don’t even necessarily know what tree species we have within 20 kilometres of Ottawa,” says field naturalist and tree expert Owen Clarkin. “There’s a lot of change happening. There’s a lot of clear-cutting occurring. There is climate change. Our push has been documenting what’s there today, so we can think about trends going forward.”

Clarkin is part of a small group of dedicated amateurs using historical surveys of the area and filling in gaps in our knowledge about biodiversity in the region. These citizen science efforts are critical to understanding the current state of biodiversity in the region, and fall largely outside of what he describes as fundable research.

“What we’ve got with the Ottawa Field Naturalists Club and other like-minded organizations is a small group of people who are essentially scouring the landscape for these species and ecosystems that have, at least in 2020, slipped through the cracks,” he says. “We’re trying to basically find amphibians in areas where they’ve not been found before, but they should be there, find trees where they’ve not really been documented well, but they should be present.” Clarkin says the Field Naturalists Club is undertaking a few research projects. “We’re doing things that we know are valuable academically, but that the funding cycle has moved on from. Trees are basically not really topical anymore. But they’re still there. We’re picking away at it on our weekends.”

We’re doing things that we know are valuable academically, but that the funding cycle has moved on from. Trees are basically not really topical anymore. But they’re still there.

Clarkin is a chemistry researcher by profession, but has pursued his passion for tree conservation since childhood, after seeing beloved trees on his family’s property die of dutch elm disease. His current work centres on “trying to fill in the gaps on things that we think are problems that have fallen outside of the official recovery plans.” In some cases, this means gathering foundational data on tree species he and his peers think are declining, such as rock elm.

“We have another project on a tree called red spruce, which is a conifer that has no diseases and that sort of thing,” says Clarkin. “It’s present, it turns out, in Eastern Ontario from Ottawa to Voyageur Provincial Park. It was not documented, historically. So it’s a high-value, old-growth forest tree.” This year, Clarkin is preparing to publish the results of a five-year effort to document that tree. “It’s here as a wild tree. Some of them are 25 metres tall. We’re really trying to get the knowledge in terms of what’s standing today, done.”

Rock Elm just discovered at Voyageur Provincial Park and the largest known individual tree on public property and in natural conditions. Photo: Owen Clarkin.

When asked about old-growth forests in the area, Clarkin cites Gillies Grove in Arnprior, noting that “it has an original white pine and other tree forest that was never cut,” as well as Shaw Woods, close to Eganville. “There are other places that are relatively unknown, that are probably as good and may be old growth or very close to that. Scientifically, they might be among the most important places to document because they are so rare now,” says Clarkin. “If we’re not careful, we could lose it all if we revert back to historical practices. It’s a little scary when you think about it, because there is very little left.”

When asked about how he captures and shares his work, Clarkin points me to iNaturalist, a public scientific database. He posts all his work there, which to date amounts to around 28,000 observations of trees and life forms. “I try to be quite technical,” says Clarkin. “I’ll photograph the whole tree, from some distance if possible. Then the trunk to show what the bark looks like.” Clarkin notes that while bark can be somewhat distinctive, it’s probably the least distinctive angle of a tree. “Much more distinctive are the twigs where things are currently growing.”

Clarkin works with an inexpensive, high-zoom, point-and-click camera. “I can get pretty much diagnostic detail of twig features, we’re talking buds and leaf scars and also the leaves themselves if they’re present, if it’s not winter. Also flowers and fruit if they’re present. You want to show at least a reasonable view of all of those details to say ‘I’ve got this endangered species, not that common or that invasive species’. You want to really have reasonable data to draw conclusions from.”

I want people to have the access to the data that we gather, so that either we can teach them what we’re finding, or if we were wrong on something, we want that to be known.

“I want people to have the access to the data that we gather, so that either we can teach them what we’re finding, or if we were wrong on something, we want that to be known,” says Clarkin. He has also worked with Ecology Ottawa to support their Bioblitz. These are opportunities for people to spend time outside, wherever they are, photographing and uploading the living things they observe, and that help build a stronger collective understanding of Ottawa’s biodiversity. Ecology Ottawa’s Living City Organizer Natasha Jovanovic says, “We want to help collect this information about the status of our urban biodiversity in order for policy-makers to know if the conservation policies in place are accomplishing their goals or not.” Jovanovic also notes that, “although the City of Ottawa has policies supporting biodiversity, there are no monitoring practices in place.” The organization is conducting bioblitzes to raise awareness and contribute to a baseline of evidence. They are also petitioning the city to implement a systematic way of monitoring Ottawa’s nature.


For more information on the Ottawa Field Naturalists Club, check out their website. Want to contribute to Ecology Ottawa’s #BioBlitz? Check out their page on iNaturalist.