A Rare Life Butterfly: the American Snout

American Snout

The American Snout is a rare-to-uncommon butterfly in Ontario which, like the Monarch butterfly, breeds here but is unable to survive the winter. It is a tropical butterfly, found as far south as Argentina, and its permanent range reaches only as far north as the southern United States. However, it is strongly migratory, and southern populations in the U.S. undertake large-scale migrations through most of the eastern United States and into southern Canada each breeding season. It is found regularly in the Carolinian Zone of southwestern Ontario, with strays reaching as far north as Algonquin Park, Manitoulin Island and Ottawa, where it was found each year at the Fletcher Wildlife Garden in the years between 2008 and 2012. I never went to see them there, and thought if I ever wanted to add this species to my life list I would have to look for this butterfly in southern Ontario.

I was surprised when I checked the Eagleson Ponds iNaturalist project on the evening of August 10th and saw that this species had been reported there only a few hours earlier! The observer had taken an excellent photo of this butterfly, and there was no doubt in my mind as to what it was – this butterfly has a distinctive profile with its long snout (actually the labial palps, which are part of the butterfly’s mouthparts that function as sense organs), scalloped wing edges and a squared-off forewing. Like many other brushfoots with irregularly-shaped wings, the underside of the hindwing contains various shades of gray and brown which gives it the appearance a dead leaf, while the underside of the forewing contains a large orange patch along with a couple of smaller white spots that can be sometimes be seen if the wings are partially open.

I headed over the following day after lunch. I saw a few other good butterflies and odes (more on that later!) and I was about to give up on my search for the American Snout when I finally found one on the mudflat in the southern-most pond where it projects into the water like an unfinished boat ramp. It was sipping moisture from the damp soil, and its wings were entirely closed, showing no hint of orange. If I hadn’t seen it walking around I might have missed it altogether.

American Snout

This individual showed a lot of brown on the underside, and was so fresh that it appeared metallic; some individuals can show a violet sheen if seen from the right angle. While I was photographing it I caught a glimpse of another orange butterfly flying by. I couldn’t relocate it, though I believe it might have been a second one. I continued walking around the southern pond, and eventually found a second individual nectaring on some purple thistle flowers. This one was displaying the orange and white patches on the forewing. It is clearly a different individual than the one in the above photo, as there is a distinct dark brown mark in the middle of the hindwing shaped like a sideways harp that is quite different from the butterfly shown above.

American Snout

As this was a lifer, I followed it around for a while, hoping it would perch with its wings open. It never did, but instead spent its time actively feeding on the thistle nectar. Adults are also known to feed on fermenting fruit; the flower nectar of aster, dogbane, dogwood, and goldenrod; and minerals found in damp soil, mud puddles, and even human sweat.

American Snout

I didn’t understand this species’ connection to the Eagleson ponds until I reported this sighting to Ottawa’s version of the “Rare Butterfly Alert”. Others were able to refind two or three individuals over the next few days and mentioned seeing Hackberry trees in the area. American Snout caterpillars feed exclusively on different species of Hackberries, including the local Common Hackberry. As such, most American Snouts spend their lives in areas where these trees grow (for example, the Fletcher Wildlife Garden) looking for mates and laying their eggs on the Hackberry leaves. So at some point earlier in the spring, a female American Snout must have found her way to the Hackberries at the ponds, mated with a male, and laid her eggs on the leaves. Unlike Monarchs, however, they do not migrate south in the fall, and as they cannot survive the winter here, each year we must wait and see if these species will migrate north to Ottawa again.

Common Hackberry with its distinctive ridged bark

Ottawa butterfly enthusiasts will be familiar with Hackberry trees because the only population of the Hackberry Emperor butterfly in eastern Ontario is found on Petrie Island, where a number of the distinctive Common Hackberry trees grow. Like the American Snout, the caterpillars of the Hackberry Emperor feed exclusively on various species of Hackberries. I went looking for these trees at the storm water ponds, and found a line of them at the extreme southern end of the pond next to Hope Side Road. The familiar ridged bark caught my eye, and I checked the leaves to be sure – the leaves are alternately arranged on the branch, with a rounded asymmetrical base, a long tapering tip, and toothed edges.

Common Hackberry

The American Snouts were last seen at the ponds on August 15th. Not everyone who looked for them found them, suggesting there were only a handful of individuals present. I went two more times and never saw them again, though I was still hoping to see and photograph one with its wings open.

Still, it was a treat to see the ones I did find there. It was also a beneficial learning experience in that the Eagleson Ponds are now on my radar as a potential spot for future American Snouts to show up. This is just another situation showing that it really does pay to visit the same spots over and over again at different points in the year – different insects have different flight seasons, and so much can be missed by not visiting your favourite conservation areas and green spaces regularly.

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