The long grass almost hides the noxious weed scattered throughout the wetland. If it were not for the purple pompom-like flower that grows from their stem, you might miss them altogether.
Walking through the grass, you are reminded of their name as your legs and arms get pricked. Canadian Thistle, despite its name, is native to Europe and northern Asia. It can be spotted in disturbed areas like roadsides, riverbanks, and logged forests, where it can outgrow native species.
Bending down, you begin your work to pull the weed out by its root. Despite the heat of the day, you have donned on your thickest pants, a long-sleeved flannel, and work gloves to protect yourself as much as you can from the thistle’s sharp spiny leaves. Yet, regardless of your efforts, you still feel the leaves’ subtle prick at least a thousand times that day.
Canadian Thistle is just one of the invasive species our work-pods are working to remove from our wetland sites as part of wetland maintenance. Other invasive species that are being removed include:
- Black Locust
- Bull Thistle
- Common Tansy
- Curly Dock
- Douglas Water Hemlock
- Hounds Tongue
- Oxeyed Daisy
- Poison Hemlock
- Reed Canary
- Sow Thistle
- Wild Mustard
- Witch Grass
Maintenance of our wetland sites does not begin and end at the removal of invasive species. Our crews are doing a number of tasks to make sure our wetlands can continue to be functional.
Lac du Bois is located 20 kilometers north of Kamloops. It is a popular destination for paddling, fishing, wildlife viewing, and many other outdoor activities, some of which can harm the delicate area and threaten the species that live there. Recreational pursuits like off-road vehicle use, littering and fires all negatively impact the vegetation and the wildlife in the area.
This spring alone, the Nature Conservancy of Canada work-pod removed 2.5 tons of garbage and campfire waste from the site. This is comparable to the weight of four and a half adult male Grizzly bears that are not hurting for food.
Julie Chesley and Angela Melney, Wetland Field Technicians for NCC, point out that much of the waste, like fire pits and garbage, is left behind from the winter season when people come up to go snowmobiling. Managing this human activity has been the biggest challenge at the Lac Du Bois wetland site.
“At this site specifically, we have a lot of issues with firepits, with people off-roading, and we have a lot of weeds here because people track them in, “said Melney. “We’re trying to manage human activity on the landscape and keep our invasives back and out of our wetlands so we’ve put in a fence to help reduce human disturbance in this area.”
Since the fence was installed, the crew have seen a difference, “We’ve been up here almost every week, and we’ve noticed there hasn’t been a lot of activity beyond the fence. So, things like putting in a fence, we know can help,” said Chesley.
Although the fence still allows for people to access the wetland for recreational purposes like canoeing and fishing, it is helping to keep motorized vehicles and campfire debris a healthy distance away from the sensitive wetland ecosystem.
Herbivory Exclosures and Fencing
Fencing has been used in several ways to help protect our wetland ecosystems. One of the tasks for the Ducks Unlimited Marsh Recession work-pod was doing maintenance on goose herbivory exclosures at Sturgeon Banks. These exclosures are created with 6 PVC pipes that are wrapped around with stainless steel airplane cabling, creating a fence-like structure around certain vegetation.
Noah Haave, Field Crew Supervisor for the Marsh Recession work-pod, explained why these exclosures are being used, “Basically, what they are doing is preventing geese from getting into areas where there are particular marsh species that they like to grub the roots out of […] we don’t know the exact reason the geese don’t like these exclosures, but we know they are protecting key plant species.”
There are a number of theories why the marshes of the Fraser Estuary, which includes Sturgeon Banks, are receding. These theories include erosion, sea-level rise, increased salinity, nutrient inputs, and herbivory by geese.
As the team works to maintain the exclosures by tightening the steel cables and removing any seaweed or debris, Haave noted that more needs to be done to protect the marsh vegetation.
“These exclosures do protect a lot of the vegetation and do reduce herbivory. We are looking into potentially having it be a bit more of a larger scale so we can protect more vegetation in a larger area, as these exclosures are a bit small.”
The B.C. Wildlife Federation work-pod is using fencing to protect their wetland sites in a number of ways. Fencing has been installed at a couple of sites to prevent livestock from using them as watering holes, which can lead to vegetation degradation. They have also installed turtle nesting fencing, drift fencing for bullfrog management and repaired a number of previously installed fences.
Many of our project wetland sites have trails for people to use to view wildlife and enjoy the beauty of the wetland. These trails need to be maintained for safety but also to keep the disturbance to the vegetation to a minimum.
McQueen Slough, just north of Dawson Creek, is one of the sites managed by Ducks Unlimited. It is a popular wetland that birders and nature enthusiasts frequent to observe wildlife.
Over the summer, Katie Mitchell, Field Technician for the Ducks Unlimited Northern crew, has continued to maintain the trails and boardwalk around the slough. Much of the work the Northern Ducks team worked on pertained to the maintenance of the wetland sites.
For Mitchell, it has been a wonderful experience, “It was really awesome. We got to go to a bunch of restored wetlands that Ducks has and looks after. We did trail maintenance, monitored and maintained old dams, and removed trees where they were impacting the strength of the dam. We also got to do invasive species removal. It was super awesome because I got to go to different sites in this area and see a lot of different wetlands and different species of ducks and birds.”
A Little Care goes a Long Way
The piles of picked Canadian Thistle are quickly bagged. One bag turns to two, then three. By the end of the day, there are 20 bags full of thistle. The crew are exhausted from the day’s work, but their energy is high, knowing the reward of their labours. With the Canadian thistle gone, the native plant species will have a better chance of not being out-competed by the creeping root systems of the thistle. However, invasive species removal requires continued maintenance and monitoring to keep these pesky plants out.
Without the Wetlands Workforce project, it is unknown whether much of this maintenance work would have been possible this year, let alone for next year or the years to come.
The maintenance of our wetlands is critical to their resiliency.
“By continuing to do this work, we are able to make sure these communities stay healthy into the future. We’re able to make sure that the wetlands that we work on, and hopefully ultimately conserve and preserve, are able to help us continue to deal with flood mitigation, remove contaminants and ultimately make the landscape healthier and better for everyone in the future.”katie Mitchell, Field Technician, Ducks Unlimited and B.C. Wildlife Federation