|Adult Eastern Comma (Polygonia comma)|
|Overwintered adult mourning cloak (Nymphalis antiopa)|
Both species breed in the spring, and this is the only time of year this territorial behavior is observed. Apparently my theory of defending breeding areas has largely been dispelled in recent years according to a local entomologist, but it seemed the easiest and most obvious explanation. More appealing than, "the commas get confused and can't tell the mourning cloaks from a female comma").
Where: Centennial Woods