A 2004 survey reported 32 species of butterflies on San Juan Island. First to arrive are sky blue Spring Azures, then Pale Tiger Swallowtails, Purplish Coppers, Silvery Blues, Brown Elfins, Two-Banded Checkered Skippers, and many more. This is also home to the rare Island Marble butterfly, thought to be extinct but recently discovered on the island in 1998. You may spot one flitting around nonnative mustard plants.
Last updated: March 31, 2015