Photo by johnslowry of a monarch nectaring on Joe-Pye Weed.

The Monarch supergeneration is on the move to Mexico and you can currently observe them migrating across Ontario.

Roosts (i.e. where Monarchs spend the night) have already been seen from Ottawa southwest to Windsor. You can observe a roost anywhere within the migratory route of Monarchs, but in Ontario they're most likely to be observed in the evenings or early morning close to the shorelines of Lake Ontario and Lake Erie. Presqu'ile Provincial Park on Lake Ontario and Point Pelee National Park on Lake Erie are two excellent locations to observe this phenomenon.

If you observe a Monarch roost, remember to add it to this project! We also appreciate all monarch observations whether they are a roost or not. If you do observe a roost, consider revisiting the location on subsequent days and recording what you see.

If you are interested in completing point counts of Monarchs anywhere in Ontario, we have a Survey123 form that can be completed using the Survey123 app or browser on your cellphone (survey link: https://arcg.is/1q5q5O0). This survey allows the capture of absences and the direction of migrating monarchs.

We appreciate any and all observations!

In the late summer, monarchs in Ontario begin their 3000 km journey south to Mexico. Unlike the spring migration north, the fall migration is undertaken by a single generation of butterflies.

Monarchs are diurnal migrants, meaning they migrate during the day. At night, migratory monarchs roost on trees or shrubs and often form large groups of butterflies. These roosts are usually near meadows or other habitat that provides good foraging opportunities for the monarchs so they can feed and gain the energy required to complete their migration.

Based on our current knowledge of monarch roosts in Ontario, roosts are typically found in proximity to the Great Lakes but they can be found anywhere with suitable habitat in southern and eastern Ontario. Locations such as Point Pelee on Lake Erie and Presqu’ile on Lake Ontario are good places to spot monarch roosts.

The best times to look for roosts are evenings and early mornings. Monarch roosts can be a single individual to many hundreds or thousands of individuals.