Pacific tree frogs can be heard across the qathet region beginning each March. Many residents and visitors to the northern Sunshine Coast know about the hundreds of western toads that migrate together, crossing the Inland Lake trail in late summer.
Both are native to the area and considered species-at-risk due to habitat loss. But, there is another threat: the American bullfrog, considered an invasive species that has caused havoc to aquatic ecosystems in BC.
American bullfrogs are just one example of invasive, non-native species in the qathet region.
According to the World Conservation Union, invasive plant and animal species are the second most significant threat to biodiversity after habitat loss. But, what is the big deal about non-native/invasive species and should people living in qathet be concerned?
Invasive Species Council of British Columbia (ISCBC) science and research manager Nick Wong said we should all be concerned about invasive species.
"They are one of the greatest threats to biodiversity globally," said Wong. "Preventing the spread is still our most effective management tool."
Many folks have heard of the Broombusters, a dedicated group of volunteers who go out every spring to cut down Scotch broom, an invasive plant. The names given to many invasive species are telling: knotweed, ragwort, hogweed, creeping buttercup and bull thistle conjure up images of a stubborn weed that won't go away.
“It goes without saying that every community should take invasives seriously and when it comes to cutting Scotch broom, it is the single most effective thing to do next to a Fire Smart program," said former Powell River Fire Rescue fire chief Terry Peters, who also sits on the ISCBC board. "Get involved with the local Broombusters and help stop this highly flammable weed from infesting your community."
Peters said Powell River has been tackling the Scotch broom problem for nine years and has more than 125 registered cutters.
"There is a role for each person and organization to be alert and reporting," said Wong. "Coastal Invasive Species Committee (Coastal ISC) and ISCBC work together and provide information and resources for reporting."
qathet Regional District (qRD) adopted an Invasive Plant Management Strategy in 2017 out of concern that: "Invasive plants reduce biodiversity, alter ecosystem functions, create management costs to natural resource industries, reduce recreational opportunities, reduce property values and ultimately cost taxpayers millions of dollars each year."
Unfortunately, releasing a seemingly harmless pet snapping turtle, for example, into the ecosystem can create predators, competitors, parasites, hybridizers and diseases of native and domesticated plants and animals.
"Some of the most popular pets that seem so harmless can cause catastrophic damage outside the tank," said Wong. "These include goldfish and red-eared slider turtles."
Wong said releasing pets into the wild is inhumane, dangerous and illegal.
"American bullfrog populations have been established in parts of BC, including the Lower Mainland, Vancouver Island and the Sunshine Coast," said Wong. "The frogs were first brought here in the 1930s and 1940s for frog-leg farming, and for stocking backyard ponds."
Wong said American bullfrogs can grow up to 20 centimetres long, and that's not including the legs, and they are the largest frogs in BC.
"They are predators with a big appetite and will eat almost anything they can fit into their mouths, including salamanders, young turtles, small rodents, many insects, garter snakes and even other frogs," said Wong. "This diet makes American bullfrogs a serious threat to BC’s wetland wildlife, including the northern red-legged frog and the western painted turtle, both species at risk. "
The American bullfrog is designated as a regional containment/control species by the BC Provincial Priority Invasive Species List.
"Invasive species such as knotweeds and Scotch broom require effort [to eradicate], but the result is reclaimed and restored lands," said Wong. "You will have also prevented these species from spreading to new areas."
The knotweed was introduced to BC for use in gardens and landscaping due to its rapid growth and attractive appearance, according to Wong.
"Knotweeds can grow through concrete and asphalt, damaging infrastructure resulting in significant control, management, and repair costs," added Wong.
Getting rid of invasive species seems like a never-ending and impossible task but Wong warns about the consequences of not taking action.
Eurasian watermilfoil creates dense mats which reduce oxygen levels, impede water flow, and outcompete native aquatic plants. It also reduces salmon and trout habitat and can even cause lake closures due to dangers to swimmers and boaters.
Eastern grey squirrels compete with native squirrels and eat the eggs of native birds. Common burdock can trap bats and small birds.
Yellow flag iris chokes out natural vegetation and blocks turtles’ paths to lay their eggs. Scotch broom forms dense thickets that restrict movement of wildlife and displace native plants. It is also very flammable, increasing wildfire severity and chance of spread.
European green crab damages eelgrass beds, which juveniles of BC’s iconic pacific salmon use as nurseries.
Wong said invasive species also impact traditional Indigenous practices.
"Invasive species can restrict access to harvesting sites for first food and traditional medicines, destroy wildlife habitat and threaten traditional ways of life," added Wong.
qathet is a coastal community and many folks use boats for fishing and crabbing. Many species can cling to boats, equipment and gear. Cleaning the bottom of a boat before transporting it to another body of water is important to combat invasive species.
"For most species only a small fragment of the plant is needed to take root and grow a new colony," said Wong. "Similarly, zebra mussels and their larvae can be extremely small and can attach to boat hulls, trailers, motors, equipment, and gear."
ISCBC has an education program called Clean Drain Dry that outlines rules for boaters in BC.
Wong said there are many ways individuals and communities can help stop the spread of invasive species, including in our own gardens.
"In the garden, practice the PlantWise principles and choose native or non-invasive plants for your yard," said Wong. "When it’s campfire season, never move firewood and always buy local wood."
Wong said using local wood prevents the spread of invasive insects that love to hide in firewood.
Aside from Japanese knotweed and Scotch broom, Coastal ISC has identified invasive species to be on the lookout for in the qathet region
Giant hogweed: This aggressive invader was first introduced to North America as a garden ornamental. It looks a lot like the native plant cow parsnip, but giant hogweed can grow up to six-metres tall. Giant hogweed stem hairs and leaves contain a clear, highly toxic sap that can cause burns, blisters and scarring.
Common periwinkle: This ornamental ground cover popular for its fast growth and dense coverage was deliberately introduced from Europe. However, it has since escaped captivity and spread rapidly through BC forest’s understories, choking out native plant species.
"All invasive species are a concern because they outcompete native species for habitat," said Wong. "Many invasive plants are a real worry especially with climate change, and the high oil content of Scotch broom, for example, makes these plants a serious fire concern."
To find out what invasive species are here in qathet, plus to know the difference between an invasive, native and introduced species, check out ISCBC interactive map: bcinvasives.ca/invasive-species-contacts-in-british-columbia. Coast ISC also has invasive species resources and ways to report them: coastalisc.com and qathet Regional District has information about invasive plants here: qathet.ca/services/waste-management/invasive-plants-in-the-region/.
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