Residents in the Comox Valley on central Vancouver Island are uniting to eradicate invasive American bullfrogs from local lakes and waterways. The Tsolum River Restoration Society is launching workshops to help individuals install tadpole traps, citing the significant threat these large bullfrogs pose to indigenous species.
American bullfrogs, which can grow twice the size of other frogs in British Columbia, have a voracious appetite, preying on various creatures such as frogs, salamanders, insects, and even small mammals and reptiles, as reported by the Invasive Species Council of B.C.
One resident diligently monitors the tadpole traps set in Maple Lake, just north of Cumberland, every two days in an effort to safeguard fragile ecosystems. Bruce Moffat, a society volunteer, initially adopted a “live and let live” approach towards bullfrog tadpoles a few years ago. However, after encountering a proliferation of invasive tadpoles in Maple Lake last year, Moffat recognized the urgent need to intervene to prevent the detrimental impact on local wildlife.
Moffat emphasized that a thriving population of American bullfrogs could severely disrupt local amphibian, fish, and insect populations, ultimately affecting birds and larger species. The Invasive Species Council of B.C. warns that the bullfrogs’ insatiable appetite poses a threat to endangered species like the northern red-legged frog and the western painted turtle.
Gail Wallin, the executive director of ISCBC, stressed the illegality of relocating tadpoles or mature American bullfrogs to new areas, as the species have been established in B.C. for decades. While complete eradication may be unfeasible, Wallin advocates for population control efforts, suggesting documentation of their activities as a crucial step.
Wallin encouraged trapping and euthanizing American bullfrogs using safe methods to mitigate their impact. The tadpole traps installed by Comox Valley residents are expected to have a short-term effect on local populations, underscoring the need for ongoing community engagement to manage bullfrog populations effectively.
To engage the community further, the Tsolum River Restoration Society is hosting workshops to educate residents on constructing tadpole traps. These traps are designed to attract and temporarily capture bullfrog tadpoles using readily available materials, costing around $25 each to make. Katie Gair, the society’s project co-ordinator, aims to empower community members to utilize these traps with proper authorization on their properties and in public spaces.
Gair highlighted that bullfrog tadpoles can be distinguished from native species in B.C. by their larger size, cream-colored belly, and mottled green markings. Removing bullfrogs is just one component of a comprehensive strategy aimed at safeguarding local species, as outlined by Gair and the Tsolum River Restoration Society.