Observation of the week – August 17-23

Good afternoon Butterfly Blitz participants. We are into the home stretch of the 2020 Butterfly Blitz, with only four weeks left to add to your butterfly observations.

We are starting to get into the late butterfly season, with a different mix of species around. Maybe you can add an Orange Sulphur to your list, or maybe you will see a Common Buckeye or a Fiery Skipper. We can’t wait to see what you find!

Our twelfth OOTW is this Great Spangled Fritillary by Christine Elliott (@c-elliott).

Christine saw this beautiful butterfly in the pollinator garden at Willow Park Ecology Centre in Norval. She says, “The first thing that struck me when I saw it was the size, it was huge! With the wings open it reminded me of other very large butterflies like the Monarch.”

Although Christine normally uses Rick Cavasin’s pocket guide for butterfly ID, she didn’t have it with her at Willow Park. Says Christine: “This is the only Fritillary species that I've seen in person, so I relied on iNaturalist to confirm my hunch that it was a GSF.”

Great Spangled Fritillary is a good guess if you see a fritillary, as it is the most observed species of that group in our region – especially in somewhat urban areas. When trying to separate it from other species, seeing the underside of the wings is key. Great Spangled Fritillary has a relatively large pale-yellow band on the hind wing, whereas other fritillaries have a narrow yellow band.

The caterpillars of Great Spangled Fritillaries eat the leaves of violets, like all fritillary species you can find in our area. Great Spangled Fritillary females lay their eggs near, but not on, violets. This is because the caterpillars don’t actually eat after they emerge from the egg – they bury themselves in the leaf litter to spend the winter and then begin feeding once it warms up in the spring.

If you have native violets in your yard and you would also like to see Great Spangled Fritillaries there, do not clean up the leaf litter in your garden until early spring. If you remove the leaves, you will also remove the caterpillars and many other insects that spend the winter there.

Check out this page from the Xerces Society for Invertebrate Conservation for more information on 'leaving the leaves'.

Posted on August 24, 2020 07:21 PM by lltimms