Finding the black petaltail dragonfly

I may never become a beetle, moth, or spider expert due to the large number of species in each of these groups. Yet, there is one group of insects that still gives me hope for a future as an amateur entomologist: Odonata, which includes both damselflies and dragonflies.

As they swiftly buzz past my ear, I always try to get a better look. Their large, beady eyes, prominent mouths, and beautiful colour patterns captivate my attention.

My parents used to tell me when a dragonfly lands on you it is a blessing or good luck. I feel honoured by their presence. These ancient insects date back some 300 million years, making them older than dinosaurs, birds, and flowering plants.

Although there are over a million known species of insects worldwide, only about 5,000 of them are dragonflies or damselflies—a far more manageable order than beetles with around 350,000 species, moths with 160,000, or spiders with 45,000. Here in B.C., we have 87 known species of dragonflies and damselflies.

I joined the Whistler BioBlitz scientists for their alpine survey on July 26 and 27 at Brandywine Meadows and Whistler Mountain as a volunteer photographer/videographer. As the mycologists I was walking down with quickly dipped into the forest to investigate some interesting slime mold, I heard that familiar buzz by my ear and looked around.

Two dragonflies settled down just a few metres ahead and allowed me to take a close-up shot. After watching them fly off, I rejoined the group of scientists at the car park where one of them was holding the very same type of dragonfly I just saw with excitement—the black petaltail (Tanypteryx hageni). In 2008, when naturalists Bob Brett and James Miskelly set out to find this particular dragonfly (whistlernaturalists.ca/single-post/walk-softly-and-carry-a-big-net), they were unsuccessful. Fortunately, during last year’s Alpine BioBlitz, Sharon and Mike Toochin finally found it!

There are only two species of Tanypteryx in the world, one in Japan and the black petaltail in North America. The larvae of the black petaltail are unique as they are not fully aquatic the way other dragonflies are and are only found in spring-fed mountain bogs where they tunnel into the moss near slow-trickling springs. The larvae come out at night to stalk prey like spiders on the surface of the moss. After about two years as larvae, they eventually emerge as black and yellow adult dragonflies.

Toochin also found another new species of dragonfly this year—the blue dasher (Pachydiplax longipennis)—which brings the Whistler Biodiversity Project’s total count up to 46 species of Odonata. Both dragonflies are blue listed in the Province of British Columbia’s List of Species and Ecosystems at risk, making them of special concern in the province.

Unfortunately, spring-fed bogs are becoming increasingly rare due to human activity and climate change. Another threat is increased siltation in their seeps resulting from clear-cutting forests. Dragonfly and damselfly habitat is disappearing across southern Canada and B.C. as marsh and pond habitats turn into cities, roads and farms. To help dragonflies and enjoy them as frequent flyers by your side, consider adding a pond to your yard or garden!

Naturespeak is prepared by the Whistler Naturalists. To learn more about Whistler’s natural world, go to Whistlernaturalists.ca.