After spending many childhood summers in the Laurentian Mountains, one significant highlight will always remain in my memory: the arrival of the fireflies! These little beetles have always been special to me because their arrival marked the end of classes and the start of summer. What could be more magical for a schoolboy? For someone like me who loved walking through meadows, this was like an explosion of nightlights, a fireworks display just for me!
At the time, my brothers and I would fetch a few jam pots from my father’s workshop to go firefly hunting. The hunt always began at dusk, without a net. We had to capture these little Lampyridae with our bare hands.
I remember well that in the heat of the moment, we would sometimes end up crushing the bug’s body between our fingers. This was a sad event for the insect but a spectacular event for me, watching the green light spread over my fingers. I couldn’t understand why this light had no effect on my fingers, other than leaving a very characteristic odour. This odour is in fact produced by toxic substances that the bug uses to protect itself.
It was only later, as a teenager, that I started understanding the secrets of this green light by reading books on entomology. It was also at this time that I realized that one of the most common beetles in Quebec, Ellychnia corrusca, was also a member of the Lampyridae family. However, unlike the twilight and nocturnal varieties, it does not produce any light. How can a firefly not produce any light? Simply because it is a diurnal or daylight species that cannot possibly compete with the sun.
Nevertheless, several kinds of fireflies produce light. But why? Bioluminescence, which is at the heart of our new exhibition Creatures of Light: Nature’s Bioluminescence, is a phenomenon that emerged a number of times in several groups during evolution. This ability therefore has more than one purpose.
In the case of our fireflies, it is a means of communication between males and females. What better way to attract a partner in the dark than by using light signals? Several species of fireflies can however be active at the same time and place. Each of these therefore evolved different features that make up as many “languages”. Flashing signals can be observed at various frequencies and colours, ranging from yellow to green to a reddish colour.
Fireflies are usually rarer in cities. You can, however, see them in parks, especially near the edge of a forest, in small, slightly damp valleys. There are 31 species of fireflies in Canada, including about 15 in the National Capital Region.
You can go firefly hunting with me on Friday, June 20, 2014, in Gatineau Park. Let’s hope we’ll be as lucky as I was in my childhood memories!
Translated from French.