by Stephanie Smith
September 01, 2016
A monarch butterfly (Danaus plexippus) alights on a flower to forage for nectar. The insect’s distinctive orange and black wings signal to predators that the species is poisonous. Milkweed, the preferred food source for monarch caterpillars and adults, produces toxic chemicals that accumulate in the insect’s body.
The bright, delicate flutter of a monarch is a common sight throughout the Chesapeake Bay watershed—but in the fall, when the butterflies begin their migration south, the view becomes spectacular. From early September through late October, millions of monarchs in central and eastern North America make their way to the Gulf States and Mexico (while monarchs in the west migrate to southern California).
To avoid crossing large bodies of water as they migrate, monarchs are naturally drawn to peninsulas. This makes the Delmarva Peninsula a major player in the insect’s migration—but peninsulas on both the eastern and western shores of the Bay are opportune spots to sight the migrating butterflies.