At Petrie Island

Reticulate Fruitworm Moth

On July 17th, Chris Lewis and a few other friends and I went dragon-hunting at Petrie Island. Although the morning started out cool, it quickly warmed up, and as a result we saw lots of great bugs. We started our outing by searching the vegetation between the parking lot and the first small bay, usually a productive area for some of the smaller dragonflies and damselflies. This is the only spot at Petrie Island where I’ve seen Vesper Bluet and Orange Bluet, and we spent a good half hour examining the shrubs for these small damselflies. Although both species are considered common in the Northeast, Petrie Island is the only place where I’ve seen them. However, both species are more active later in the day, and since I usually do my birding in the morning and early afternoon, it is possible I’ve missed them in other places.

A Lifer Lost

In July 2011, I photographed a large Arigomphus dragonfly at Petrie Island. It had greenish eyes, a dark abdomen with rusty-coloured spots on the bottom of the last couple of segments, and an entirely yellow tenth segment. I only got two photos of the clubtail before it flew off, but the two angles showed that there was no black on the sides of the final abdominal segment. According to my research, only one species in Ontario has an entirely yellow tenth segment – the Unicorn Clubtail, a southern species that wasn’t even on the Ottawa checklist. Based on my photographs, which show the completely yellow tenth segment, a few of Ottawa’s most knowledgeable students of the odonata concluded that it could only be a Unicorn Clubtail – a new record for the region, and the 123rd species observed in the Ottawa area.

Unicorn Clubtail

Unicorn Clubtail

In July 2012, I was part of a team of dragon-hunters which went looking for this species at Petrie Island. The team included Bob Bracken, Chris Lewis, and Mike Tate. Bob and I spotted a large Arigomphus dragonfly, and I took one quick photo before he tried to net it. His attempt failed, and this photo is the only record we have of that 2012 clubtail. Again the image shows an entirely yellow tenth segment.

Unicorn Clubtail

In June 2015, Chris Traynor and another member of the OFNC Facebook group photographed Arigomphus dragonflies with what appeared to be entirely yellow tenth abdominal segments west of Ottawa. It seemed strange for the Unicorn Clubtails to pop up suddenly in the west end, especially since there had been no Unicorn Clubtail sightings anywhere in the region since 2012. Chris Lewis, Chris Traynor and I decided to post our photos to the Northeast Odonata Faceboook Group, which includes many prominent members of the Dragonfly Society of the Americas, several professional writers, bloggers, and authors, and other really knowledgeable dragonfly enthusiasts who have been studying these insects a lot longer than Chris, Chris, and I have.

After studying the images I posted, Ed Lam, the author of Damselflies of the Northeast: A Guide to the Species of Eastern Canada & the Northeastern United States (2004), noted that the cerci (upper claspers of the terminal appendages) appear shorter than the epiproct (the lower appendage) in the photos, which supports the similar-looking Lilypad Clubtail (A. furcifer) rather than Unicorn Clubtail (A. villosipes). He then took the time to photograph these two species with the appendages in the exact same position as the ones in my photos. The resulting diagram he put together was conclusive:

Arigomphus appendages (by Ed Lam)

Not only are the upper claspers shorter than the lower clasper, they are even the same shape with a heavy downward arch.

In the Facebook discussion, Chris Lewis responded with the comment that “structure rules again” – that is, structure is more important than colour or pattern when it comes to identifying odes. She also asked about the extensive pale yellow colour on the tenth segment of the two dragonflies I photographed. According to the Algonquin field guide and other online resources, the Lilypad Clubtail has only an elongated yellow spot on top of the tenth segment- the sides of the segment are very dark. She asked Ed if the extent of the paleness down the sides was variable in both species. Ed answered that in his experience, the amount of darkness on those last segments is variable on both Lilypad and Unicorn Clubtails.

So there it is – there are no Unicorn Clubtails in Ottawa (that we know of), and the next time someone spots a clubtail with an entirely yellow tenth segment, it’s best to check the shape and size of the claspers, as these are the most reliable field marks for identifying an odonate to species.

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Author’s Note: Many thanks go to Ed Lam for the use of the image comparing the claspers of each species, and for his helpful comments on Northeast Odonata. Even though I lost a lifer, I gained a lot of knowledge about these two species and how to differentiate them. This knowledge will hopefully serve me well in the years to come, and is worth more than a tick on a checklist. Though it was kind of cool having a first Ottawa record while it lasted…! 🙂

An OFNC outing at Petrie Island

Eastern Amberwing

On August 2nd, 2015 I led a dragonfly outing at Petrie Island for the Ottawa Field-Naturalists’ Club. Because I would be leading it on my own, and because the small size of dragonflies and damselflies makes it difficult to point them out to large groups, I decided to limit the group to ten people. Fellow dragon-hunters and Birds Committee members Chris Traynor and Lorraine Elworthy signed up for the outing, as did Jakob Mueller, who led the reptile and amphibian outing at Sheila McKee Park earlier in the year. I recognized Lynne Ovenden from the OFNC; the others were all unknown to me.

I started our outing by talking about the differences between dragonflies and damselflies, as well as the different groups belonging to each family. We would be looking for spreadwing damselflies, which hold their wings out at a 45° angle instead of parallel to their back; emeralds and darners, which are most commonly found flying through the air searching for aerial prey; and skimmers, which tend to hunt from a perch and are usually the most approachable types of dragonflies for photography. As I was speaking, a bright green female Eastern Pondhawk was hunting from a perch in the vegetation, often flying out to snatch an insect from the air. At one point it even landed on one of the group members!

Dragon-hunting: Petrie Island Specialties

Blue Dasher

If you are a dragon-hunter in Ottawa, summer isn’t the same without a stop at Petrie Island in July. It is a great spot to see a number of species that are difficult to find elsewhere, so I try to get out there a couple of times each season. On July 6th Chris Lewis, Mike Tate and I visited Petrie Island together. The weather was not the greatest – the sun danced in and out of the clouds all morning, and it grew very hot and humid as the morning wore on. By the end of our two-and-a-half hours there, we were hot, sticky and uncomfortable and I only wanted to go home to my air-conditioned house. The intermittent overcast conditions meant that we didn’t see as many species as we would have liked, but we did manage to see several Petrie Island “specialties”. The birding was good, too, though we didn’t see anything really exciting. An Osprey was the best bird of the outing, though the usual House Wrens, Tree Swallows, Common Yellowthroats, American Redstarts, Eastern Kingbirds, and Great Crested Flycatchers were present.

In Search of the Boghaunter

Hudsonian Whiteface

The Ebony Boghaunter is a rare dragonfly that spends its life in the forested sphagnum bogs of the northeast. It is a small dragonfly, approximately 1.1 to 1.4 inches in the length, and is black with white rings near the base of the abdomen. The face is dark metallic brown; males have bright green eyes while females have gray eyes. In Ottawa their flight season occurs in May and June, making them one of the earlier species on the wing. Because of their preference for acidic bogs, fens and wetlands dominated by sphagnum, they are not easy to find. Fortunately eastern Ontario is home to two large bogs, Mer Bleue and Alfred Bog further east, both of which have boardwalks that provide access onto the bog. Mer Bleue is close to the city and the only place I’ve ever seen them. These small emeralds are not as skittish as other dragonflies; look for them perching on tree trunks or on the boardwalk itself where they can be easily approached.

Red Faces and Amber Wings

Eastern Amberwing

On the Friday before the August long weekend I spent half an hour of my lunch break at Hurdman. I would have stayed longer but several dark, threatening clouds began moving in and I got caught in a brief shower. I didn’t expect to see many migrant birds yet, but at least three Eastern Kingbirds were around, and when I started pishing in the woods two American Redstarts, two Red-eyed Vireos, a Gray Catbird, and a Yellow Warbler all popped into view. All of these guys will be leaving in another month or so, though some (such as the Yellow Warbler and Eastern Kingbirds) will be leaving sooner rather than later. There weren’t many butterflies around, but I saw an Eastern Tailed Blue along the path between the bus station and the bird feeders (all of which are empty in the summer) as well as a couple of Ambush Bugs. These tiny predators sit motionlessly in flowers such as Queen Anne’s Lace and wait for unsuspecting insects to land on the colourful flowers.

Return to Petrie Island

Vesper Bluet

On Sunday I returned to Petrie Island with Chris Traynor, a friend from the Ottawa Field-Naturalists’ Club who has recently taken an interest in the odonata. He was so intrigued by the Vesper Bluet photos I posted on Facebook that he decided to try and find them for himself; I offered to meet him there as I wanted another chance to see them, as well as the Swamp Spreadwings and Unicorn Clubtail. I had also just gotten a new camera, the Sony Cybershot DSC-HX200V, that I wanted to try out. It has a 30x zoom and a few other bells and whistles I was hoping to play with.

Petrie Island and Mer Bleue

Belted Whiteface

I was off work on Friday, July 5th, so when Chris invited me to go out dragon-hunting with her, Bob and Mike Tate, I jumped at the chance to spend some time with them in the east end. I did not know that it would be the last time that the four of us would go dragon-hunting together or the last time I would see Bob.

We started off the morning at Mer Bleue. It was very warm and humid, and thick, dark clouds kept blocking out the sun. Although it constantly looked as though it might rain at any time, we were lucky that it held off until the afternoon, after our outing had ended.

Chasing a Unicorn

The following day Chris, Bob, Mike and I met up again to go dragon-hunting at Petrie Island. We had two goals: Unicorn Clubtail, a species first discovered in the Ottawa area last year by yours truly (at Petrie Island); and Hackberry Emperor, a beautiful butterfly which is rare in our area and is only found near stands of mature Hackberry trees. It was hot, and at first our quest for dragons was unproductive. We found a few Eastern Forktails and a couple of Swamp Spreadwings at the edges of the marsh, but the large number of Blue Dashers, Common Pondhawks, Dot-tailed Whitefaces, and Slaty Skimmers I remembered from previous outings were missing.

Swamp Spreadwing

Blue Dashers Emerge!

Blue Dasher

On June 16th I visited Petrie Island to look for birds and bugs. While the birds were my primary focus this outing, I was curious as to whether any Blue Dashers were present. I was hoping that last year’s colony had successfully reproduced, and given that my Algonquin field guide indicates they fly in June, this seemed as good a time as any to check.