Transformation

On Sunday, July 7, 2024 Jeff Skevington, known chiefly for his work on butterflies and flower flies, discovered a first record of dragonfly species for the Ottawa region: a Painted Skimmer (Libellula semifasciata) in Burnt Lands Provincial Park. This species is at the northern edge of its range in southern Ontario, though there is one record from Algonquin Park and one record from Smiths Falls on iNaturalist. This dragonfly has the body of a Four-spotted Skimmer and wing pattern of a Calico Pennant, though the spots are brown instead of red, with a wide amber patch at the base of the wings. The veins at the leading edge of the wings are colourful, too: gold in females and red in males. It is a distinct dragonfly within its range, and outside of it too: Paulson states it is probably migratory in the northern part of its range, and it has been observed moving north over the past 15 years. Perhaps it was only a matter of time before one was seen in Ottawa.

I thought briefly about trying to see the Painted Skimmer the following Saturday, but the forecast, as well as the chances of trying to re-find a bug that had been seen 6 days ago, deterred me: the forecast called for a sunny high of 29°C with the humidity making it feel closer to 40. Burnt Lands Provincial Park is a hot, shadeless alvar better suited for grassland species such as Clay-colored Sparrows than woodland species such as Wood Thrush, and with no trees, running water, or shelter I decided – reluctantly – to head elsewhere, though I would have loved to have seen the Painted Skimmer. It is a species I will have to keep an eye out for while visiting southern Ontario.

I ventured over to Pinhey’s Point instead, figuring it would be cooler along the river. I was hoping to find some interesting clubtails and emeralds, but identified only a Black-shouldered Spinyleg and a Lancet Clubtail. At one point I found an emerald buzzing around a patch of grass and tried three times to catch it to no avail. It looked like a Racket-tailed Emerald, so I wasn’t too worried about missing something terribly exotic.

From there I drove over to Sheila McKee Memorial Park, and while I was there I got a message from Chris Traynor saying he was on his way. We met up, and I was thrilled to show him the large meadow and open corridors where I had made some of my most exciting discoveries this year – emeralds and pennants and darners, oh my! The emeralds were mostly gone – I saw only two, or maybe just one, Prince Baskettail zipping around, and we didn’t see any Halloween Pennants, but there were still several Canada Darners, Blue Dashers, and a couple of female Eastern Pondhawks flying around and perching along the edges of the clearing. Meadowhawks were emerging, and we found a couple of mature White-faced Meadowhawks. We had come for clubtails, however, and it didn’t take us long to find our first Black-legged Spinyleg of the day perching in a sunny spot. This one was bright yellow; the one at Pinhey’s Point had been dull green.

We made our way down to the beach, which was still quite narrow. There we found a few Lancet Clubtails, a Cobra Clubtail which flew off before I could photograph it, and a Midland Clubtail which stayed put.

As we tried to get over the trunk of a tree leaning over the water we spotted a teneral dragonfly clutching a skinny branch above the river. We tried to get close to it to photograph without getting our feet wet, but after confirming it was a clubtail Chris went all in and stepped into the water to get a few shots. It was mostly colourless, but it had the same striped appearance of the Elusive Clubtails I had seen two weeks ago on Canada Day.

We spent some time watching it, and then something amazing happened: a dragonfly nymph in the water started crawling up Chris’s leg, looking for a place to complete its transformation! This was even better than seeing all the teneral clubtails two weeks ago, as seeing a dragonfly in its nymph, or naiad stage is much rarer: it doesn’t take long for them to crawl out of the water, find a secluded place, and begin emerging.

We found a quiet, sunny place on the shore and put the nymph on a rock where it immediately began crawling toward a secluded crevice.

Once the nymph had found the right spot, it began breaking free of the exoskeleton by creating a hole in the thorax and propelling itself backward. Here you can see the top of the thorax and back of the head just beginning to emerge from the hole above the “wing sheaths” attached to the back of the exoskeleton. Note that the dragonfly’s larval shell looks dead and inanimate compared to the living nymph in the photo above.

For some reason these wing sheaths remind me of a parachute strapped to the back of a human, as they both fulfill a similar function: to contain the structures needed to “fly” until they are ready to be deployed and expand to full size. This image shows the dragonfly from a slightly different angle; you can see the yellowish-green stripes of the thorax breaking free.

The dragonfly has now pulled its head and upper body from the exoskeleton. Most dragonflies crawl onto vertical surfaces so that by the time they reach this stage of emergence, they just need to lean backward and allow gravity to assist them in pulling the rest of their bodies free. This one was not on a vertical surface and still managed to free itself. Many dragonflies are not able to complete their emergence and die while half-stuck in their larval shell.

Here is a short video I took of the dragonfly emerging:

Once the dragonfly is free from its shell it continues to rest where it emerged, pumping haemolymph into its abdomen and the veins of its wings to extend them to full size. This is a slow process, as shown in the video in my previous blog, taking up to an hour for damselflies and three hours for dragonflies! You can see the wings beginning to inflate while the dragonfly rests on top of its cast-off exuvia.

 Fifteen minutes later, the wings are as long as the abdomen which has also expanded.

In the meantime, Chris had walked down the beach looking for more clubtails. He found another freshly emerged teneral that looked a bit odd, so he brought it back to where I was watching the first one emerge, carrying it on his hat. He put the hat down in a calm, sunny spot and we watched that one, too. The pattern of its body was much more vibrant, and it is almost certain that it is an Elusive Clubtail.

The dragonfly on the hat eventually flew away, and once the dragonfly that had crawled up Chris’s leg and emerged in the rock crevice began to unfurl its wings I held my finger beneath it to pick it up and take some more photos, confirming the species as the Elusive Clubtail.

Eventually it, too, was ready for its maiden flight, and flew up into the trees where it would be safe from predators while its body continued to harden and become less vulnerable. Dragonfly emergence and transformation is a fascinating process, and I wished I could have watched it long enough to see the body attain its mature colours. However, it’s not for nothing that it has been named the Elusive Clubtail; as soon as they are ready to fly, they spend most of their lives away from human eyes either high up in the trees or patrolling far out over the river. Safe travels little one!