Butterflies of Early Spring

Spring Azures

Butterflies emerge in late winter or early spring as soon as the first warm, sunny days arrive and the temperatures reach about 13-15°C. This could happen as early as mid-March here in Ottawa, although the butterflies usually don’t stay out for very long – the nights are still cold in late March and early April, and they may not become fully active until the weather warms up to a consistent 15°C in late April. The first butterflies that emerge are those that spent the winter in their adult form, hibernating in mixed or deciduous woodlands beneath the bark of trees, in brush piles, or in other nooks and crannies where they are protected from the wind and biting cold Arctic air. Only a few species hibernate as adults; others overwinter as caterpillars, eggs, or pupae contained within their protective chrysalises. Still others are unable to tolerate Canadian winters in any form, and migrate south to warmer regions – the Monarch is the most familiar of these.

The butterflies that overwinter as adults are all members of the brushfoot family. One of the largest and most diverse butterfly families, these species are all characterized by having four normal legs, while the front pair of legs are much reduced in size and covered in hairs, giving them the appearance of tiny bottle brushes. If you look at any Monarch photo, for example, the butterfly appears to have only four legs. The earliest species you are likely to see around woodlots in Ottawa are the Mourning Cloak, Eastern Comma, Compton Tortoiseshell, Gray Comma, and Milbert’s Tortoiseshell (although this species has become less common in Ottawa in recent years and is difficult to find). The first two are common along woodland trails within the Greenbelt or any forested park in the city, while the Compton Tortoiseshell and Gray Comma are less common – you may need to look a little further out of the city to see these. Compton Tortoiseshells seem to have had good years the past two years in Stony Swamp, and I photographed this one on May 2, 2020 at the Beaver Trail in Stony Swamp.

Compton Tortoiseshell

Eastern Commas are quite common, although they look quite similar to Gray Commas. The keys to differentiating the two are the number of brown spots on the hindwing wing above, and the shape of the silver comma on the hindwing below. They both come in two forms: the paler “winter form” and darker “summer form”. The winter form has orange and brown hindwings above, while the summer form has almost entirely black wings. In both forms the line of orange spots along the outer edge is visible. The summer form emerges from its chrysalis in June. It lives long enough to breed, but dies before the winter; its offspring, the winter form, emerges in August and lives long enough to overwinter and reproduce the following spring. This butterfly was photographed on May 14, 2020 at the Richmond Lagoons. It looks to be in pretty good shape for a butterfly that is about 9 months old!

Eastern Comma

The Mourning Cloak is one of our most familiar butterflies. It, like the Eastern Comma, has two broods each year, but in Ottawa they overlap so that this species can be found any time between late March and early November. Both broods are similar in appearance, with the first brood emerging in June and the second brood emerging in August. Like the Eastern Comma, the second brood is the one that overwinters in the adult form. Because of its wide range of foodplant preferences, the Mourning Cloak is not limited to woodlots but can be found in city parks and gardens as well. The one was found in Deevy Pines Park in Bridlewood on May 18, 2020.

Mourning Cloak

As the weather warms up, those butterflies that overwinter in the pupal stage begin to emerge. These include the non-native Cabbage White, Mustard White, Clouded Sulphur, all swallowtails, the elfins, and Northern Spring Azure. In fact, the Northern Spring Azure is usually the first non-overwintering adult butterfly I see each year in the woods, along with the familiar Cabbage White in city parks and gardens. I saw my first Northern Spring Azure and Henry’s Elfins at the Beaver Trail on May 2nd, but wasn’t able to photograph them; then, a few weeks later I visited Deevy Pines park on May 18th with the hope of finding Eastern Pine Elfins there. These are small gossamer-winged butterflies that breed in areas where pines grow, as the caterpillar feeds on various species of pine. My rule of thumb in looking for this species is to watch out for small butterflies any place where I hear Pine Warblers singing – I’ve had luck at the South March Highlands and the Beaver Trail extension that goes toward the Lime Kiln trail network, and thought that Deevy Pines might be worth a look too.

When I first arrived at Deevy Pines I had no luck with any butterflies. It was a warm, sunny day, without much of a breeze, so any butterflies present should be flying. Then I saw a Mourning Cloak in the woods, and circled the trail until I came to a big, sunny, sandy clearing. Several small blue butterflies were flying, and as I watched they battled each other several times, spiraling up into the air together any time one came too close to another. I counted at least six Northern Spring Azures in that small area, and had no luck in finding any to photograph – they just kept flying along without ever landing. I circled the trail one more time, and when I returned to the clearing I had better luck – I found a pair mating!

Northern Spring Azures (mating)

I saw a darker butterfly about the same size fly out of the vegetation to chase the azures from time to time, returning to its perch high up in the shrub after each sally. I thought it might be the Eastern Pine Elfin I was seeking, but it turned out to be a Henry’s Elfin instead. These butterflies are also found in sandy areas with pine trees, often in proximity to the Eastern Pine Elfins. Although they are said to visit flowers, I’ve never seen one do so; however, males often gather along damp trails and roads to sip moisture from the ground.

Henry’s Elfin

Like hairstreaks (another member of the gossamer-winged butterfly family), male elfins are territorial and sit on perches to watch for females and male intruders passing through their territory. The male guarding this spot must have been successful, for I saw a pair mating in the shrub – it’s the first time I’ve ever witnessed this species mating.

Henry’s Elfins (mating)

The Silvery Blue, a slightly larger member of the gossamer-winged butterfly, also hibernates as a pupa and emerges in early May. One generation is present in our area, so after they disappear around early July we won’t see the adult form again until the following year. It is most common in open woodlands with adjacent meadows, although they may also be seen along roadsides, in parks, or in small waste areas in cities where they feed on flowers or perch on the damp ground. This one was photographed at Shirley’s Bay on May 23, 2020.

Silvery Blue

I had another Silvery Blue, and got my Eastern Pine Elfin for the year, the following day at South March Highlands. The Eastern Pine Elfin was watching over his territory from a rock.

Eastern Pine Elfin

The duskywings are the earliest skippers to emerge in our area. They, along with the cloudywings, are members of a group called spread-winged skippers. These skippers are large, mostly brown in colour, and perch with their wings fully open or partially closed – in both cases both sets of wings are held at the same angle, and move in unison (the small orange grass skippers often hold and move their forewings and hindwings independently of each other). Duskywings overwinter as fully-grown caterpillars in the leaf litter.

The Juvenal’s Duskywing is the easiest duskywing to identify, with a small row of small, translucent white bars “stacked” together at the top of the forewing close to the outer edge, with two to four more single white spots between the middle of the wing and the lower edge. They are fairly widespread in our region, found in woodlands and woodland edges.

Juvenal’s Duskywing

Three other duskywing species are on the wing at the same time as the Juvenal’s Duskywing: the Dreamy Duskywing, which is unique in that it has no translucent white spots on its forewing, and the Columbine and Wild Duskywings, which are nearly identical and have a couple of translucent white spots on the forewing. They are best told apart by size (difficult in the field) and their association with the larval foodplants of the caterpillar: columbines for Columbine Duskywing, and crown vetch for Wild Indigo Duskywing (it is this plant that has allowed it to successfully establish itself in Ottawa in recent years).

Duskywing sp.

I got some nice pictures of several duskywings, and posted them on iNaturalist, but when even our local experts say that determining species through photos alone is impossible, I’m not going to attempt to narrow it down further myself! However, since Red Columbine (Aquilegia canadensis) is quite prevalent throughout the South March Highlands, I wouldn’t be surprised if the majority were Columbine Duskywings.

Duskywing sp.

Several were flying in the southeastern portion of the conservation area, and many landed on flowers, particularly dandelions. Note that each has a different pattern of small white translucent spots on the forewing.

Duskywing sp.

These early species often fly from May through early to mid-June. Although their time is too brief, their appearance in the spring is one of the things I look forward to every winter, and I enjoy seeing them flit through meadows and woodlands when the trees haven’t fully leafed out yet and the spring ephemerals are still in bloom.

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