It’s been a surprisingly good month for butterflies at the Eagleson storm water ponds. The highlight, of course, was the American Snout seen there on August 11th, but in addition to that particular rarity I’ve seen members from all five butterfly families – not a difficult achievement over the course of a month, but one that is almost impossible to do in a single outing. Swallowtails are large butterflies with long tails, and their wings are mainly yellow and black with iridescent spots of blue and orange. The whites and sulphurs in our area are medium-sized butterflies with either yellow or white wings, most of which perch with their wings closed. The gossamer-winged butterflies are very small butterflies that also perch with their wings closed, and come in many different colours. The brushfoots are large to medium-sized butterflies with only two functional pairs of legs; they count the most well-known butterfly species among their number, and many are migratory. Skippers are small butterflies mainly dressed in orange or brown, and many species hold their forewings and hindwings at two different angles, giving them a characteristic “fighter jet” appearance.
Swallowtails are not common at the ponds, and usually the only species I see here is the Black Swallowtail – however, today I was startled by an Eastern Giant Swallowtail floating over the grass next to the southern-most pond. I hoped it would land so I could get a photo for my iNaturalist project as this was the first one I’ve ever seen here, but it kept flying and I lost it as it headed toward Hope Side Road. Black Swallowtails are much more common at the ponds, and even so I might only see one or two here each season; however, they, too, are difficult to photograph, as they don’t often feed in one spot for very long, and tend to flutter their wings to support their heavy bodies as they nectar on the flowers. Black Swallowtails have two generations each season, and fly from May to early September in our region. This individual was seen on August 11th feeding on the Purple Loosestrife; the larger patch of blue and disappearing upper row of yellow spots on the top wings indicate that she is a female.
Of the whites and sulphurs, both Clouded Sulphur and Cabbage White are common at the ponds. Both have multiple generations, and fly from May to October. I usually see multiple individuals of both species on each visit, particularly later in the summer. Cabbage Whites – the abundant, non-native white butterfly seen even in urban gardens and backyards – are more likely to be seen resting on a leaf or nectaring on flowers, and it is much easier to photograph them than the Clouded Sulphurs. I found a pair mating on some goldenrod today; I don’t often find them in photogenic settings such as this, and thought them worth photographing.
Gossamer-winged butterflies are usually more difficult to find as most only have one generation per season in our region and are restricted to particular habitats. Some of my favourite butterflies are included within this family, which includes the blues, the coppers, the hairstreaks and the elfins. The blues are generally more widespread than the other members of this family, and the Eastern Tailed Blue is one of the easier species to see as it is found in many open habitats, including old fields, roadsides, woodland clearings, and urban parks. It has been increasing in Ottawa over the last 20 years, and I usually see them on most visits to the ponds. They have two or three overlapping generations each season and are one of our latest-flying butterflies.
The Bronze Copper is another gossamer-winged butterfly with two generations each season, and this is the first year they’ve shown up at the pond. I tend to see them around the marshy edges of wetlands, and have observed them at Roger’s Pond, Petrie Island, and Mud Lake in the past. I don’t encounter them very often, so it has been a real treat to have them at the ponds this summer. This individual was photographed on August 11th:
A week later, I encounter another Bronze Copper, this one nectaring on a thistle blossom. Males can be distinguished from females only from the upperside of the wings; the upper forewings of the male are a deep copper colour with small black spots, while the upper forewings of the female are pale orange with thick brownish-black borders. From the little that is visible in these images, I am guessing that both individuals are males.
I’ve also encountered a few different brushfoots at the ponds this month. Both American Lady and Painted Lady have shown up in the past, but they are not common visitors to the pond. As migratory butterflies, their population in Ottawa fluctuates depending on whether there is a large influx of these species from the south. I saw one Painted Lady here earlier this year, but my last American Lady sighting was in 2016. When I saw this butterfly land in the dew-laden grass early one morning, I expected it to be a Painted Lady and was surprised instead when it turned out to be an American Lady – there are only two large spots on the hindwings, instead of a row of four nearly equal-sized spots.
I encountered another American Lady (or perhaps the same individual) a week later. This time I saw just enough of the upper wings to see the single white dot in the first submarginal orange cell below the black cell. This white spot is not always seen in every American Lady, but it is never present in the Painted Lady.
The Common Ringlet is a common species in open grassy areas, and the Eagleson ponds are no exception. Unlike other members of the brushfoot family, this species rarely perches with its wings open. Most individuals have a small black ring near the apex of the forewing; however some, such as the one shown below, are missing this eponymous black ring.
Crescents (genus Phyciodes) are common in the Ottawa area, however, this is only the second one I’ve seen at the Eagleson ponds. Crescent identification is tough, and anyone who has read this blog over the years may recall that I’ve publicly declared my intention of giving up on this genus once or twice. Males of both Pearl and Northern Crescents are mostly black and orange, while females often have shades of both yellow and orange in the forewing. This is a female, which has a much “busier” pattern than the male. Seen on August 16th, it was identified for me by Ross Layberry on iNaturalist. I presume this is because the black veins crossing the orange cells of the hindwing are quite noticeable in this individual; they are absent in Northern Crescents.
Monarchs have been found in good numbers at the ponds over the last few years, although they are usually most frequently seen in August and September after they have started migrating. Here they feast on the asters and thistles, the Black-eyed Susans and goldenrod, and all the other late summer flowers blooming at the ponds. Although the Common Milkweed has stopped flowering, it is worth checking the leaves to see if any caterpillars are present. These two adults were photographed on August 17th and August 28th.
The lookalike Viceroy, however, does not show up here very often. This one appeared on August 5th, and is only the second one I’ve photographed at the ponds. While it looks similar to the Monarch, it has a thick black line crossing the width of its hindwing which is visible on both sides of the wing. It is also smaller than the Monarch, and has a more direct flight style. Unlike the Monarch, the Viceroy is capable of surviving our northern winters, which it spends as a caterpillar inside a shelter made from a rolled leaf tip. By late May the Viceroy caterpillars have metamorphosed into adults, which live long enough to breed and lay the eggs that will form the second generation which generally flies from late July to late September.
The last family of butterflies, the skippers, were once thought to be an intermediate life form between butterflies and moths. Their antennae are neither clubbed like butterflies, nor feathered or threadlike like the antennae of male and female moths. Instead, they are slightly hooked at the end. Their heads are large and their bodies are thick and furry, giving them a mothlike appearance. However, skippers fly during the day and are more closely related to true butterflies than they are to moths. There are three types of skipper in our region, two of which breed at the storm water ponds. Spread-winged skippers are characterized by their dull colours (usually brown with some white spotting) and tendency to perch with their wings held open along a single plane; the intermediate skippers, or skipperlings, of which only one species is found in Ontario (but not at the ponds); and the grass skippers, named for the caterpillars which typically feed on grasses and sedges, while the adults hold their forewings and hindwings at two different angles, giving them a characteristic “fighter jet” appearance.
The Wild Indigo Duskywing, one of the spread-winged skippers, looks similar to several other species in our area, notably the Columbine Duskywing. This species has been breeding at our ponds for a few years now (at least since the reconstruction in 2016), feasting on the abundant Purple Crown Vetch in its caterpillar stage. As it has two to three generations per year, I usually see them in small numbers throughout the warmer months – perhaps one or two most visits.
Of the grass skippers, only the tiny Least Skipper breeds here – I have been seeing them regularly at the ponds since 2018, with multiple individuals each visit. The smallest butterfly in Ontario, it is easily overlooked as it flutters through wet, grassy areas next to wetlands, lakes, wet meadows, and even roadside ditches. Its body is slim, and the abdomen extends well past the base of the folded wings – a trait especially noticeable in males. There are two overlapping generations per year, so they are present throughout the summer.
I never spent much time at the ponds looking for bugs before the reconstruction (2014-2016), but all the flowers that have been planted since then have turned it into a great spot for butterflies – especially later in the summer. Not only is there a nice variety of breeding species in this small suburban area, but the flowers and plants seem to hold a strong attraction for butterflies which breed nearby, as well as wandering migratory butterflies such as the American Lady and American Snout. The ponds are worth visiting any time when the water isn’t frozen, but summer is my favourite season when the butterflies (and dragonflies) add colour and charm to the abundant flowers that grow along the water’s edge.