European fire ant sightings have been reported in Maple Ridge as well as other Lower Mainland communities, and if they spread as far as experts believe they will, they could end up costing the province more than $100 million annually in 20 years.
In a new report commissioned by the B.C. Ministry of Environment’s Ecosystems Branch, a team of ecologists, environmental economists, and city planners speculates that, if left unchecked, the fire ant (Myrmica rubra) invasion of the Lower Mainland could render gardens, schoolyards and golf courses unusable if the ants were “to eventually occupy all areas where they could physically survive and thrive.”
The report, Preliminary Damage Estimates for Selected Invasive Fauna in B.C., attempts to estimate the total costs, including damage and control efforts, if the ants eventually spread all along the coastline.
“It’s the doomsday ant scenario,” said lead author and ecologist Donald Robinson of Vancouver environmental consulting firm ESSA. The stinging pests could invade more than half a million homes.
The associated costs include health care and veterinary bills, as well as pesticides and lawncare spending. There is also a chance they could spread from green spaces and community gardens to profitable crop land. The estimates do not include declines in property value.
Calculations are based on the known costs associated with the red imported fire ant (Solenopsis invicta) that has established itself in the southern U.S. and Pacific regions. For example, that species costs Hawaii roughly $211 million annually and Texas $580 million.
In B.C., sightings have more than doubled since last year, and the fire ants have been reported in Vancouver, including the University of B.C. Endowment Lands, an equestrian park and a botanical garden, as well as in North Vancouver, Victoria, Burnaby, Chilliwack, Maple Ridge, Courtenay and Richmond, where even pet dogs were suffering from attacks, according to Thompson Rivers University entomologist Robert Higgins. They can strike any time, but swarm and sting particularly if the nest is disturbed.
The report’s hypothetical scenario is based on Higgins’ research into how the ants have spread in the last 15 years and projections over the next two decades.
“A myriad of problems have spun out of this one species,” he said. “It could be quite expensive.”
Higgins estimated 2,000 to 3,000 homes are currently affected.
Fire ant colonies are “cryptic and difficult to locate,” according to the report, but can have up to 15 queens in a nest and 1,000 workers that can sting, causing painful, ugly red welts and allergic reactions.
There are very few known effective treatments for fire ants. Boric acid solutions are commonly used, but rarely work, and Higgins is now experimenting with trapping the bugs in a container, where they can be destroyed. So far it has worked on one nest in North Vancouver.
Experts believe the ants are arriving in garden soils and plants, and advocate soaking roots in cold water before transplanting to halt the invasion.
- Zoe Mcknight is a reporter with the Vancouver Sun
@ Copyright 2013