They are just beginning to get noticed even if some have been established here for twenty years. They could be counted on the fingers of one hand. But with the weather and the changing climate, these three exceptional butterflies gradually spread. One of them is considered one of the most beautiful in the world, another has become the largest of all our diurnal species and the third is clad all in azure. Maybe you will have the chance to meet them this summer.
PHOTO CHARLES J. SHARP, WIKIMEDIA COMMONS
Of European origin, the magnificent peacock is now added to the list of butterflies in Quebec, which includes 136 diurnal species and nearly 3,000 nocturnal species. Well established in the Montreal area, it remains relatively rare. The specimen opposite is drinking nectar from a lilac.
Through maritime
Considered today as the most colorful of our diurnal butterflies and one of the most beautiful in the world, English io, of its scientific name, arrived at the port of Montreal, probably in 1996, to be discovered the following year, in May, at Charron Island. Of European origin, this peacock was a female that had spent the winter as an adult. Still rare, but established in the metropolitan area, the European migrant had an incredible chance of surviving in Quebec, says entomologist Étienne Normandin, author of the book Insects and other arthropods of Quebec.
“It was necessary for the insect to resist the winter, for the female to be pregnant, for her eggs to be able to develop and produce viable caterpillars and to discover a plant that was suitable for their food”, explains the researcher.
PHOTO PIERRE GINGRAS, SPECIAL COLLABORATION
Arrived by sea as was the case in particular in Halifax or New York, the peacock is unloaded at the port of Montreal to settle in Quebec. This butterfly overwinters dormant as an adult. Here is a specimen photographed in Boucherville on April 15th.
The director of the Montreal Insectarium, Maxim Larrivee, indicates for his part that the absence of predators or parasites has greatly contributed to the survival of the species, especially since it reproduces little, i.e. only one times a year, from April to May, hence its very slow growth. We can see the adult at the very beginning as well as at the end of the season. Unlike other overseas insects such as the gypsy moth or the emerald ash borer, which have proven disastrous for our flora, the peafowl caterpillar feeds on nettles, species widespread among us. So much so that it is not in competition with the butterflies here.
PHOTO FRANK VESSEN, WIKIMEDIA COMMONS
Widespread in Europe, the blue argus is an azure blue color as its name suggests. It is now well established in Montreal and Western Quebec.
By plane-cargo
Magnificent too, but more modest in size, about three centimeters long, the blue argus arrived in Mirabel in 2005, probably with freight from Europe, where it is widespread and known by several popular names, including that of common blue. But unlike the peafowl, its progression has been very rapid, as it breeds two or three times a summer. Still from Mirabel, it is now found almost everywhere in the metropolitan area, in southwestern Quebec, in Ontario, especially in Toronto, in Vermont and in summer in New York. It should eventually invade the entire continent. “By dispersing in this way, they avoid competition between them at the same time”, says Étienne Normandin.
PHOTO FRIEDRICH BOHRINGER, WIKIMEDIA COMMONS
Sexual dimorphism is marked in blue argus. In the photo, a male and a female (right) with folded wings.
As in Europe, even local ants have been called upon to adapt to Quebec soil, our experts explain. Adults will sometimes even lay eggs where ants are raising aphids for their honeydew. It is that during its growth, the caterpillar of the argus also begins to produce honeydew making the happiness of the ants. In return, they ensure the safety of their protegee instead of putting it on their menu. In addition, the blue argus does not look harmful either, insists Maxim Larrivee. It feeds on sweet clover, birdsfoot trefoil and clover, common plants, and does not compete with our native species.
PHOTO MONGO,WIKEMEDIA COMMONS
The Great Hairstreak comes to us from the United States. It is spectacular as much by its colors as by its impressive size. It is the largest of the diurnal butterflies in Quebec.
The crossing of the border
Arrived from the United States about ten years ago, the great hairstreak crossed the border on its own. Reported for the first time at the Montreal Botanical Garden in 2012, the spectacular insect experienced a very rapid expansion towards the north from the beginning of the century thanks to global warming.
With its wingspan of 12 to 15 cm, the great hairstreak is the most imposing of all our day butterflies, even larger than our famous monarch. Towards the end of the 19the century, a population had survived about fifty years in the Outaouais before dying out and the American populations even regressed towards the south for a certain time before their recent flight towards the north, without anyone really knowing why. The insect’s progression is attributable in large part to longer and warmer autumns allowing the second summer generation to complete its life cycle before the first frosts, explains Maxim Larrivee, who participated in a major study on the great frogfish. tail. The butterfly caterpillar feeds on keyboards, a large shrub also called prickly ash, but also on rue des jardins or even fraxinelle, a decorative plant. Planting rue in the garden (be careful, the plant is allergenic) also helps to attract the butterfly, as the director of the Insectarium has experienced.