COLUMN: Butterflies on the move

     Through Monarch Watch tagging studies and citizen science opportunities we have learned that monarch butterflies of the eastern United States and Canada migrate to the mountains in Mexico while monarch populations from the West Coast migrate to locations in California for the winter. We have also discovered that it is the great, great, great, great grandchildren of the overwintering monarchs that make the migration each fall.

     Every spring and summer, generations of monarchs complete their lifecycle on milkweed plants in the United States and Canada before that special fourth generation heads to their ancestral overwintering grounds. Truly astounding! Right now is the peak of the monarch migration in Iowa. The awe-inspiring migration of the monarch butterfly is now well-known, but did you know that there are other species of butterflies that migrate to survive the winter?

     Many butterfly species that migrate are much less understood or studied. Butterfly species that have seasonal migrations, prompted into movement by decreasing photoperiod and declining temperatures, follow the flowers, their food source and plants they need to lay their eggs on. A few of the migrating butterflies that we know of  include the painted lady, American lady, common buckeye, cloudless Sulphur, question mark, clouded skipper, red admiral, little yellow, gulf fritillary, and fiery skipper.

     The medium sized, orange and black, painted lady butterflies are sometimes confused with monarchs. Their migration is equally amazing and fascinating and is finally beginning to become clear to scientists across the globe as citizen scientists once again help collect important data. Painted lady butterflies are noted as one of the most widely distributed of all butterfly species with individuals said to be found on almost all continents except South America and Antarctica. Painted ladies are generalists when it comes to host plants and can be found using around 300 different species of plants worldwide to lay their eggs on. Plants in our area that are suitable host plants for larva include thistles, daisy, burdock, hollyhock, aster, mallows, and most legumes. Adult painted lady butterflies migrating south during the fall in our area prefer nectar from flowers like asters, sedum, goldenrod, and zinnias.

     Painted lady butterflies in North America head to the southern United States and Mexico to survive the winter. Studies have found that in Europe and Asia epic migrations each year span thousands of miles from Africa to the Arctic and back. It has also been discovered that these small butterflies can travel at altitudes over 1,500-2,000 feet at speeds up to 30 mph. Citizen science and university based research is showing similarities here in North America.

     The bright yellow cloudless Sulphur butterflies are another seasonal migrator heading south for the winter. Males have very few, if any, markings while the female may have irregular black borders on the outer edges of the wing, and dark spot on the upper forewing visible when the wings are open, and pink-edged silver spots on the lower surfaces of the wings. These butterflies are year-round residents of southern Texas, Florida and south to the tip of South America. Cloudless Sulphur butterflies often travel within 10 feet of the ground during most of their migration. When they encounter an obstacle they tend to fly over it rather than temporarily changing direction.

     Red admirals, known by their military-like chevron orange wing markings, against their dark colored wings and body are another species that migrate into Iowa from the south in the spring and possibly migrate south out of Iowa in late summer and early fall. I’m sure you’ve encountered them in your yard during the summer when males fly franticly around you as they try to chase you out of their territory. Research is ongoing as we learn more about these beautiful butterflies with an attitude.

     If you would like to help scientists learn more about our butterfly migrations join citizen scientists around the world by visiting the following websites to learn more:  the ISU Extension Red Admiral and Painted Lady Research Site: https://vanessa.ent.iastate.edu/, Journey North:  https://journeynorth.org/, Monarch Watch:   https://www.monarchwatch.org/, and E Butterfly:  http://www.e-butterfly.org/.