Homeless in Vancouver: Spotting my first fake ladybug of spring
All winter I miss the sight of ladybugs. Then comes the warmer temperatures and flowers and birdsong of spring and I still miss them.
I will apparently go on missing them because, near as I can tell, the native Canadian ladybugs that I grew up with are a thing of my childhood, permanently replaced by a nearly lookalike invasive foreign species.
The little beetle that I saw March 14, roaming around on a window, was one of these fakes. At first glance it answered to the general description of a proper ladybug.
It had the ladybug’s characteristic six spindly legs, a wee head and—most characteristic of all—a glossy, reddish orange, domed wing-case (or elytron) marked with many black spots.
It was these spots, however, that gave it away—there were too many of them.
The native ladybug, once ubiquitous in B.C. and across Canada, is the Coccinella novemnotata; better know as the nine-spotted ladybug because it always has exactly nine spots. The lookalike I spotted on Wednesday had twice too many spots to be the real thing.
Not your grandmother's ladybug
What I saw was a Harmonia axyridis, commonly known as an Asian ladybeetle in North America and as a harlequin ladybird in Europe.
This native beetle of eastern Asia takes a dizzyingly wide number of spotted and unspotted colour forms and was introduced into North America, beginning in the 1970s, to help native ladybugs perform agricultural pest control.
Thanks to its fast reproduction cycle and a hardiness to survive fairly harsh winter temperatures, the invasive Asian ladybeetle has survived and thrived over the last 40-plus years to become one of the main beetle species in Canada and the United States.
In the process it has completely supplanted native North American ladybug species, including the nine-spot ladybug, the two-spot ladybug (Adalia bipunctata), and the traverse ladybug (Coccinella transversoguttata).
Entomologists say that this overturning of native ladybugs by an invasive foreign species has happened so suddenly that the consequences (if any) are still to be determined and public initiatives like the decade-old Lost Ladybug project are trying to discern and document the effect on the North American biosphere.
I cannot speak to reports that Asian ladybeetles can bite. I have had the little blighters running all over me but I’ve yet to be so much as nibbled on by one.
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