"Fieldnotes," September 29th & 30th, 2013: "Painted Lady Butterflies," by Byron Weber / Caroline Kurtz.
http://www.montananaturalist.org/
"I first knew something was different when one of my students rushed in from recess last May and told me of all the butterflies she had seen on the playground. Later, a teacher friend reported hundreds of butterflies flying north past her home. When I got home, I grabbed my insect net and raced to a pasture covered with dandelions. The field was dancing with medium-sized butterflies, all orange with black wingtips."