Thursday 11 March 2021

Dragonflies and Damselflies of Middlesex County

I recently wrote an article on the dragonflies and damselflies (odonates) of Middlesex County for The Cardinal, the publication put out by Nature London (formally the Mcllwraith Field Naturalists). I thought I would share it here as well. The bonus if you get to see more photos than what was in print! Enjoy! 


While many are familiar with the birds, plants, and butterflies of Middlesex County, seemingly very few are aware of the diversity of damselflies and dragonflies, known as odonates, or simply odes, that can be found in the county. In fact, as of time of writing, 98 species of these insects have been found within Middlesex. Not much is known about odes in the county, and new discoveries happen all the time. I will walk through the checklist taxonomically, and discuss a few of these awesome odonates.

First up, we have the damselflies (Zygoptera). Four species of broad-winged damsels (Calopterygidae), all of the ones that knowingly occur in Ontario, can be found in the county. Ebony Jewelwings, with their striking all black wings, are quite common along streams and rivers. These can start to be observed at the end of May. River Jewelwings are similar in appearance, but are apparently much more uncommon. We have two species of rubyspots as well, American Rubyspot, which is fairly common, and Smoky Rubyspot, very rare and local, restricted to the Thames River in the extreme southwest of the county. 

American Rubyspot

Next we have the spread-winged damsels (Lestes), represented by eight species. Slender Spreadwing is one of our most numerous spreadwings, followed by Emerald Spreadwing. Amber-winged Spreadwing is much more local, with one of the best spots to see it in Middlesex being the Sifton Bog. Later in the season, you may come across the Spotted Spreadwing, which is also one of our latest flying odonates. 

Slender Spreadwing

The dancers (Argia) are always a favourite, and six species can be readily seen around almost any flowing watercourse, with some of the best spots being the Thames River, the Ausable River, and Medway Creek. Our most common species is the Powdered Dancer, which can number in the hundreds at the right time of year. Violet and Blue-fronted Dancers can often be found mixed in as well. Rarer and more local species include Blue-ringed, Blue-tipped, and Dusky Dancers, all of which are provincially uncommon. 

Violet Dancer

Bluets (Coenagrion and Enallagma) are often something that casual ode enthusiasts dismiss, as to identify them, you often need to catch and examine the genitalia of the males. It may come to a surprise to some that 16 species of these damselflies have been recorded in the county. Many are quite common, such as Familiar, Marsh, Stream, Skimming, and Orange Bluets. Others, such as Tule, Double-striped, Azure, and Rainbow are much more uncommon. The best places to see bluets are often around ponds, and the many stormwater management ponds in the London area are a great place to start!

Stream Bluet

Rainbow Bluet

The forktails (Ischnura) and sprites (Nehalennia) are our smallest damselflies, the sprites especially. Three species of forktails have been recorded, with Eastern Forktails being the most common, followed by Fragile Forktails. Citrine Forktail, an uncommon to rare vagrant to Ontario, has been recorded once, but is very likely to be found again. We have two species of sprites. Sedge Sprites are quite common, but Sphagnum Sprites are much more local, restricted to sphagnum bogs, such as at the Sifton Bog.

Next, the dragonflies (Anisoptera). The darners (Aeshnidae) are often a crowd pleaser, with ten species having been reported from the county. The season starts off strong with the return of Common Green Darners in late April to early May, and these migrants can be seen throughout the summer into the early fall, which is when they head south. Springtime Darners and Swamp Darners start to appear near the end of May, with Springtime finishing up for the season by the end of June. Another early flier is the Spatterdock Darner, a provincially rare species first found in 2019 at the Sifton Bog. This is a striking insect with its bright blue eyes. Later in the summer, the Aesha darners start to appear, and may gather in feeding “swarms” in the evening. Shadow Darner is the most common. Occasionally, a Lance-tipped may be mixed in. A rarer species is the Black-tipped Darner, which can be found in the Sifton Bog. Along streams and rivers, watch for Fawn Darners working the edges looking for their next meal.

Fawn Darner

Common Green Darner

One of our most unique groups of dragonflies are the clubtails (Gomphidae), and 13 species have been seen in the county. These dragons are by no means common, and are always a treat when they are come across. Stormwater management ponds can be good places to look for Unicorn and Pronghorn Clubtails, both of which are provincially uncommon. Along rivers, keep an eye out for Black-shouldered Spinylegs and Midland Clubtails. Rusty Snaketails have only been seen once, but should be looked for along the Sydenham River, where they were first discovered in 2019. Later in the summer, you may come across an Arrow or Zebra Clubtail, members of the highly sought after Stylurus genus. There was a flurry of excitement in June 2020 when the provincially rare Rapids Clubtails were discovered for the first time along the Ausable River, representing the first record of this previously thought extirpated species in the county since 1989. Green-faced Clubtails, another provincially rare species, were also found for the first time in Middlesex County. 

Rapids Clubtail

Spiketails (Cordulegastridae) and river cruisers (Macromiidae) are a pair of unique dragonflies, two species of which have been found in the county. Delta-spotted Spiketails are apparently uncommon and local, with Komoka Provincial Park being a good spot to see one. Swift River Cruisers can be seen along most of the major rivers in Middlesex, with its large yellow spot on the tip of its abdomen making for easy identification. 

Swift River Cruiser

Emeralds (Corduliidae) are represented by five species. The most numerous is Common Baskettail. Prince Baskettails can be found in smaller numbers. Beaverpond Baskettails are rarely encountered, and may just be vagrants, but should be looked for. The only member of the rare genus Somatochlora we have is Mocha Emerald, a provincially rare species found mostly in the southwestern part of the county, but has also been seen along the Ausable River. Racket-tailed Emerald has been seen once at the Sifton Bog, and an eye should be kept out for more! 

Our largest group of dragonflies is the skimmers (Libelluidae), of which 25 species have been recorded. Many are very common, such as Common Whitetails, Widow Skimmers, Eastern Pondhawks, Blue Dashers, Twelve-spotted Skimmers, Eastern Amberwings, Black Saddlebags, and Dot-tailed Whitefaces. Halloween and Calico Pennants, Slaty Skimmers, Chalk-fronted Corporals, and Carolina Saddlebags are more uncommon. Painted Skimmer, a rare vagrant, can occasionally be seen. Ponds are great places to see all of these species. Six species of meadowhawks have been seen as well, with Ruby, White-faced, and Autumn Meadowhawks being the most common. Band-winged, Cherry-faced, and Saffron-winged Meadowhawks are much more local. Two species of gliders, Wandering and Spot-winged Gliders, can also be found, but numbers of this highly migratory species vary year to year. 

Black Saddlebags

Wandering Glider

White-faced Meadowhawk

Of course, there are many holes in the Middlesex County list. There are several species that may occur in the county that have not yet been found, which I have listed. Many occur in neighbouring counties, some along the same rivers. Habitat and flight periods are from The Dragonflies and Damselflies of Algonquin Provincial Park and the Surrounding Area by Colin D. Jones, Andrea Kingsley, Peter Burke, and Matt Holder, as well as Dragonflies and Damselflies of the East by Dennis Paulson. Provincially uncommon to rare species are indicated by an asterisk: Vernal Bluet (ponds and rivers, May-July), *Lilypad Forktail (ponds and slow streams with water lilies, June-September), *Comet Darner (ponds, June-August), *Cyrano Darner (wooded wetlands, June-July), *Harlequin Darner (conifer swamps and bogs, May-July), Variable Darner (ponds, June-September), Mottled Darner (ponds and bogs with abundant emergent vegetation, June-October) , *Flag-tailed Spinyleg (rivers, July-August) *Riverine Clubtail (slow moving creeks and rivers, July-August), *Elusive Clubtail (rivers, June-October), *Arrowhead Spiketail (wooded streams and seepages, May-July), Twin-spotted Spiketail (fast flowing rivers and wooded streams, June-August), Stream Cruiser (rivers, May-September), *Royal River Cruiser (wooded streams and rivers, July-September), Spiny Baskettail (ponds and slow streams, May-August), Williamson’s Emerald (quiet forest streams, June-September), *Clamp-tipped Emerald (forest streams with rapids and pools, July-September), Brush-tipped Emerald (streams through wetland habitat, June-August), and *Variegated Meadowhawk (highly migratory, breeds in ponds and slow streams, April-November).

Elusive Clubtail

Watching dragonflies and damselflies is a very enjoyable, and addicting, pastime. Much like birding, you never know what you may find! Hopefully your eyes have been opened to the amazing world of odonates right on your doorstep!

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