Swallow-tailed Kite is a long-distance migrant, vacating North America for the winter. Trans-Gulf migration takes place mainly from late February through April, and August through September. Large flocks stage in late summer in southern Florida. Migrants leave Florida on favorable winds and cross directly to the Yucatan Peninsula, Mexico, where they stage again before continuing south over land to winter in northern South America. A fair number move through the coastal bend of Texas. A few are seen along the East Coast as far north as southern Canada every spring and fall.
A folklore tradition in the Southeastern United States says that holding hands with someone when you see the swallow-tailed kite means you will be friends for life. Because seeing the birds during their 10000 mile migration from the U.S. to South America and back is rare, some elementary schools still hold the tradition and allow their students to run outside whenever the birds fly over their school.