A European butterfly in Québec

The peacock is a magnificent butterfly that until very recently couldn’t be seen in Québec except at exhibitions or in books on entomology. In the natural state it’s found just about everywhere in western Europe, from Scotland down to Portugal, from Finland to Greece, but is pretty much unknown on this side of the Atlantic. However, just a few months ago, three peacocks were spotted in Pointe-aux-Trembles and in Repentigny.

The first spottings

But this wasn’t the first time the species was seen in Québec. The first North American observations of peacock butterflies (Inachis io, Linnaeus, 1758) were reported by Jacques Leclerc and André Simard in 1997, on Île Charron and at the Boisé Tailhandier in Saint-Bruno-de-Montarville. Where could these peacocks have come from, so far from their homes?

Clandestine passengers

The most likely explanation would seem to be that an egg-bearing female must have crossed the Atlantic in a container on some freighter, or wintered there. Despite a new observation in the spring of 1998, there seemed to be no other indication of a peacock population in the greater Montreal area. Then two spottings of the same butterfly happened in 2003, confirming that it had completed its life cycle in Québec.

Other individuals in the species were observed in 2006 and in 2008. In 2012, a peacock was spotted in the east of Montreal, and in 2013 another was seen in Trois-Rivières (a clue that the population could be expanding). An even more surprising turn of events, a peacock was seen for the first time in southern Ontario, in June 2014, and then in August another one was spotted in Nova Scotia. These observations outside Québec and close to international port zones support the theory that the migration of the species would have taken place onboard freighters.

Exotic, but not invasive

Just like the common blue, the other butterfly species recently introduced into Québec, the peacock does not constitute a perceived threat to our native species, who feed primarily on the same host plant, the nettle. The very gradual growth of the species in Québec, compared to the common blue, which can be found in the hundreds today at the Jardin botanique, is explained by its much slower life cycle. The peacock produces just one generation a year, as compared to three for the common blue.

Sleep all winter, and when spring comes…

The life cycle of the species includes a hibernation period in the adult state that corresponds with our winter period. These butterflies begin their period of flight at the start of spring and spend their time in places that entomologists do not explore very much. But no one can fail to be impressed by the sight of them.
With its four feline eyes on the surface of the dorsal wings, which resemble peacock feathers, the peacock succeeds in frightening off potential predators with its catlike features, an effect heightened by the whistling sound caused by the its open wings when lightly touched. It’s a striking example of the unexpected paths species take to improve their chances of survival.

Help us get to know the peacock better

Yes – you can help us deepen our knowledge about the real range of this species in Québec. Keep an eye out and share your sightings by going to ibutterfly.ca to enter the place, date, and the number of individuals you observed. It’s still possible to see the species, up to the first frost, before they take shelter under the bark of trees.

Reference : Handfield, L. 2011. Les papillons du Québec. 672p.