There only a few known sites in Ontario for this day-flying moth that emerges in mid-September and flies until end of the month. It is considered an endangered species in Ontario. There has been debate over the species name because south of us in New England (US), the moth there is called New England Buck Moth. It looks virtually identical but it seems this is a probable subspecies and is provisionally called Hemileuca maia menyanthevora. These moths belong to the silkmoth family and as you can see are fairly large. There were scores of them fluttering over the fen in the sunlight. The individuals apparently live for only a few days, long enough to mate and the female to lay eggs, but they emerge over a period of a few weeks, so there are always moths around for the few weeks of their flight period.