Rideau Canal - Alien Nymphs and Larva Bling
What's under the rocks at Colonel By Island?
EPISODE NOTES
TRANSCRIPT
Today, I’m gonna level with you, we’re just gonna look under some rocks on the shore of Colonel By Island. But if it helps, we just might find a link to an iconic horror movie and a famous artist down there.
The most obvious underside inhabitants are these nymphs. Someday they’re going to be damselflies and dragonflies, but they actually spend way more time in this form. They can be nymphs for 2 years or longer. When they emerge from the water to molt into their adult forms, dragonflies only live about 6 months. And damselflies don’t even last that long.
These chunkier guys are the dragonfly nymphs. Even in their larval stage they’re ferocious predators. That’s partly thanks to a unique adaptation: a telescoping lower jaw that can shoot out and grab other insects and even small fish.
If that reminds you of a famous movie monster you’re not alone. There’s a longstanding rumour that HR Giger’s design of the xenomorph’s signature second mouth was directly inspired by dragonfly nymphs. But from what I’ve read, it does seem more like a creepy coincidence.
In amongst all the nymphs, we can also find these strange little structures. They’re actually home to another insect. Caddisfly larvae, who build protective cases around themselves, glued together with silk, out of whatever’s available. And that might mean plant bits, rock fragments, or snail shells. Some are mobile, others anchor to rocks, some even build ‘nets’ to catch passing nutrients.
And in the 1980s, their behaviour caught the eye of french artist Hubert Duprat. He wanted to see what would happen if you controlled their access to material. He gave them gold flakes and precious stones. And that resulted in some totally blinged out caddisfly larvae.
Duprat’s intent was high-minded. He wanted us to think about the roles of the artist and the larva in this endeavour, and whether we could call their instinctive behaviour ‘creative’.
But you can’t deny the simple aesthetic value of the result. So now? Caddisfly larva are hard at work in Etsy stores, where you can buy their bespoke jewellery.
It might seem a little exploitative but whether for art or commerce, the larva actually gets a pretty good deal out of this. They’re kept in a safe place and fed, and their cases are only collected after they’ve discarded them to become adults. Turns out it’s a pretty symbiotic relationship. But you should still support them if they decide to unionize.