By mid-August most dragonfly species are on the wane. A few families are still quite abundant, particularly the darners and meadowhawks, while small numbers of other skimmers and a few clubtails often linger into September. Forktails, bluets, and some spreadwings are also still common in the appropriate habitats in August and September. This makes it worth going out to good dragonfly habitats such as large rivers, lakes and marshes to see a decent variety of species.
Large dragonflies this time of year are particularly interesting; while Common Green Darners are the most frequently encountered large dragonflies of late summer, you might come across a Black-shouldered Spinyleg basking on the rocks along the river, a Wandering Glider zipping over a meadow, a Twelve-spotted Skimmer flying above a pond, or a group of mosaic darners swarming through the air late in the afternoon. The mosaic darners are a particular favourite of mine; they are large brownish-black dragonflies with mottled spots of blue, green or yellow depending on the sex. While they spend most of their time flying through the air hunting for small insects, I often come across them perching vertically on thick stalks of vegetation below knee-height in open grassy areas early in the morning. We have several different species in Ottawa, and trying to find something other than the ubiquitous Canada and Lance-tipped Darners is a fun exercise.
The gliders are particularly interesting as they do not overwinter in Ottawa, but instead migrate from the south in the early summer, lay their eggs, emerge from the larval stage, reach adulthood, and migrate south again all in the same season. Two species breed in Ottawa: the Wandering Glider, which is found on almost every continent on earth, and the Spot-winged Glider, which is found throughout the Americas. Both have long, wide wings that enable them to travel long distances and spend most of their time hunting on the wing. Of the two, the Wandering Glider is much more common in Ottawa, but both are typically found near shallow, still or slow-moving water such as storm water ponds and the protected, vegetated shoreline along rivers. Both species often hunt over grassy fields and other open areas away from water. I was very surprised when I scared a glider up while walking through the sparse grass of the open alvar at the Rideau Trail on Old Richmond Road one early morning in mid-August. There is no water close by, and the day was heavily overcast so no dragonflies were flying. I saw where it landed in a tree and followed. I was even more surprised when it turned out to be a Spot-winged Glider rather than the more common Wandering Glider – it’s been a while since I’ve seen one.
The adults are usually reddish or reddish-brown in colour with dark spots running up the center of the abdomen, while immature Spot-winged Gliders have paired beige spots against a dark brown background. You can see the adult colouration coming in at the tip of the abdomen.
Wandering Gliders were not as common this year as they were in previous years. The Eagleson Ponds are a great place to see them (as is Hurdman, though I haven’t been there since last year), and I think I saw one there briefly once. It wasn’t until mid-September that I had the chance to photograph one at Steeple Hill Park. They are much yellower in colour than Spot-winged Gliders. The shiny wings that indicate this is a teneral.
I didn’t have much luck with darners other than Common Green Darner (Anax junius) this year. I didn’t see many mosaic darners, and of those that I did, only a few landed where I could identify them. The first was a Canada Darner on June 12 at Marlborough Forest, the second was a Shadow Darner which I caught at Andrew Haydon Park on July 24 and the last was a Lance-tipped Darner seen at Bruce Pit on September 18 with Chris T. The third sighting, however, was the best. I was checking out a few grassy areas at the Beaver Trail when I scared up not one, but two in the area adjacent to the parking lot. With one step one flew up and landed on a tree trunk….then with the very next step a second one flew up and landed on the adjacent tree trunk. I edged closer and was able to photograph both, and at first I thought I had found some Lance-tipped Darners. One was a male and the other was a female (note that her terminal appendages, called cerci, are missing). In the photo below, the anterior green stripe on the side of the thorax looks rippled rather than notched, which is how Lance-tipped Darners appear to me.
While the female had mostly greenish markings, the male had green markings on the thorax and blue spots along the abdomen.
The female flew off as soon as I circled around to get a better look at the stripes on the side of the thorax; the male was much more cooperative and remained on the tree bark. Here the anterior green thoracic stripe doesn’t look rippled, like a Lance-tipped Darner; it appears more strongly notched on one side, similar to a Canada Darner…though the notch in the Canada Darner is much deeper.
It wasn’t until I got home and uploaded images of both individuals to iNaturalist that I realized both were Green-striped Darners based on iNaturalist’s suggested identifications. I took a close look at the male’s appendages and realized they did not have the tiny spine at the tip which would be expected in Lance-tipped. In fact, when I uploaded separate photos of the thorax, the appendages, and the dorsal view of the full body, iNaturalist identified each photo as Green-striped Darner, proving how accurate its computer-based identifications (called Computer Vision) can be.
Interested in finding more darners, I headed over to Bruce Pit two days later. I started my outing with a walk down the toboggan hill to look for odes around the water. Meadowhawks were quite numerous, and I even saw a Band-winged Meadowhawk. This site is one of the most reliable for this species, which has a wide reddish-tinted band at the base of the hindwings.
White-faced Meadowhawks were also still flying. Colin Jones, one of the co-authors of the Algonquin Field Guide, verified for me that it is virtually certain that all meadowhawks with pristine white faces in our region are in fact White-faced Meadowhawks. Further south, this species does not always have a clean white face and interbreeds with Cherry-faced and Ruby Meadowhawks, causing identification issues… meadowhawks south of the border need to be examined in the hand to reach a positive identification. However, in our area this is not an issue. Colin Jones spoke at a virtual OFNC event a few months ago and I was thrilled when he answered my question.
The Autumn Meadowhawk was my third meadowhawk species of the day. This female is brownish-red, her pale brown legs and triangular ovipositor hanging below the end of the abdomen making her easy to identify.
From there I walked around the pit to check out the open areas at the back of the pond. Both the grassy field and the openings onto the water can be good for dragonflies, and I decided to head for the water first. A Spotted Spreadwing perching on a branch was great to see; this is one of the darkest spreadwings in our area, and is widespread throughout the region. Note the deep sapphire blue eyes and the stubby lower claspers at the tip of the abdomen of this male.
I was surprised when I saw a second spreadwing perching right above the water. This one was blue in colour, with distinct shoulder stripes. It was another male, so I caught it in order to examine the shape of the upper claspers; it turned out to be a Northern Spreadwing. This species is quite similar to the Sweetflag Spreadwing, both in physical appearance and clasper shape, and the best way to tell males apart is by examining the upper claspers under magnification. These two species have two teeth on each upper clasper; in the Sweetflag Spreadwing the distal tooth is quite small, and quite distant from the proximal tooth. In the Northern Spreadwing, the distal tooth is larger and close to the proximal tooth, giving it a more jagged appearance. Almost all of the confusing spreadwings I’ve examined here with my hand lens have been Northern Spreadwings.
After I finished checking the water I headed to the grassy field at the back of the trail. This is the same area where the Summer Tanager turned up in November 2016, and where I’d had both Green-striped and Lake Darners on September 9, 2019. A few darners were soaring about 20 feet up in the air, but every one I checked turned out to be a Common Green Darner. I found one perching, and took a quick photo:
Eventually I spotted a mosaic darner patrolling the shady edge of a group of trees. I waited to see if it would turn around and fly back the way it came, but it shot up over the trees and disappeared. To my disappointment, this was the only mosaic darner I saw.
I noticed a tiger beetle flying along the sandy path ahead of me, and waited for it to land. This one was extremely cooperative and allowed me to not only walk up to it, but lean in close with my camera. I was surprised to see the greenish patch down the center of the elytra; it was a Festive Tiger Beetle, a species I’d seen for the first time at Burnt Lands in May! Tiger beetles are quite fascinating…I never knew how many species there were in our region until I started paying attention to the dull brown ones, each having its own pattern of pale spots.
A few days later, on September 18th I visited Steeple Hill park in search of migrants. It was a great day for birds; I had ten species of warbler (Tennessee Warbler, Nashville Warbler, Common Yellowthroat, American Redstart, Magnolia Warbler, Bay-breasted Warbler, Chestnut-sided Warbler, Palm Warbler, a male Black-throated Blue Warbler, and several Yellow-rumped Warblers), a Scarlet Tanager, a Brown Thrasher, a House Wren, two Gray Catbirds, a Red-eyed Vireo and a Blue-headed Vireo, a Ruffed Grouse, and a Dark-eyed Junco. With a start time of 7:30 am I didn’t expect to see many dragonflies, but after 9:00 I found two. The first landed on a low-growing shrub between me and the sun, and with the light shining behind it the first thing I noticed was the gleaming golden band on the leading edge of the forewings. I circled behind it to get a better look, and confirmed it as a Saffron-winged Dragonfly. I found a second one in a different field hunting from the shrubs, although this photo doesn’t show the reddish leading edge very well. This is the first time I’ve seen this species here, and I wondered if they were breeding in one of the quarries.
Later that day I had a chance to see another when my friend Chris T. and I met at Bruce Pit. We were mainly interested in looking for darners, but spent some time along the water at the bottom of the toboggan hill first. A few meadowhawks were still flying, including a Band-winged Meadowhawk.
We were also happy to see a Saffron-winged Meadowahawk perching on the sand along the north shore of the pond…it’s been a while since I’ve seen this species here, so it was good to know they are still around.
We retraced my route to the back of the pond and found one mosaic darner in the open area on the east side of the pond, a Lance-tipped Darner perching among a group of reeds. We weren’t able to catch it and didn’t see any other mosaic darners on our outing. We also looked for tiger beetles in the sandy areas but couldn’t find any.
Although I was disappointed with how few darners I found this year, I was happy with the ones I did manage to see. I was also happy to photograph both glider species, and to find Saffron-winged Meadowhawks in three different locations close to home. Bruce Pit is an amazing place for a wide variety of species, and is worth visiting throughout the dragonfly season. It’s too bad our season is so short here in the north, as many species are only on the wing for a few weeks (some only in a few specific places), and there are too many locations to visit during the prime months of June and July while working full time. At least the friendly little meadowhawks will still be around for another six weeks or so, making it possible to see dragonflies on the wing well into November.