Tracy Menzies had been struggling with slugs in her backyard garden, often losing the battle for her harvest. However, this year, her strawberries flourished beautifully. The reason behind this success seems to be the presence of European wall lizards, an invasive species known for rapidly spreading and devouring various creatures, including slugs.
Living near the Gorge Waterway in Saanich, Menzies noticed a surge in the number of wall lizards in her yard recently. These small reptiles, ranging from a few inches to larger sizes, have been seen feasting on slugs, as observed by Menzies, who attributes their disappearance from her yard to the growing population of wall lizards.
Gavin Hanke, the curator of vertebrate zoology at the Royal B.C. Museum, estimates that there are approximately 800,000 to a million European wall lizards in British Columbia, primarily concentrated on Vancouver Island. These lizards have spread as far as Campbell River, causing concerns about their environmental impact due to their voracious appetite for invertebrates.
Biologist Nicholas Wong from the Invasive Species Council of B.C. mentioned the lack of official management programs to control the lizard population growth. The competition for food and space with native lizards is another issue raised by Wong, indicating the potential ecological disruptions caused by the invasive species.
The origin of the wall lizard population in B.C. dates back to an intentional release of 12 lizards in 1970. The lizards find a suitable habitat in Southern Vancouver Island’s climate, enabling their rapid expansion. Despite the challenges posed by their spread, Hanke emphasized the difficulty of eradicating the lizards due to their adaptability to various environments.
To prevent further spread, Hanke recommended maintaining a minimalistic garden to deter the lizards. Cooperation among neighbors is crucial in controlling the population, as individual efforts may prove futile if neighboring properties harbor the invasive species. The curator also cautioned against relocating the lizards to new areas, as this could exacerbate their spread.
In conclusion, the invasion of European wall lizards on Vancouver Island underscores the complex challenges posed by invasive species and highlights the importance of proactive conservation measures to mitigate their impact on local ecosystems.