Monarch butterfly migration is underway: Here's how to track it

Monarch butterflies are migrating south across the U.S. right now and you can join in on their incredible journey. Every year in the fall they travel thousands of miles from their springtime breeding grounds in the northern U.S. and Canada to overwintering sites in Mexico. The butterflies take signs from the environment around them like day length and temperature to know when it's time to fly. These monarchs are riding autumn cold fronts, surfing the uplifted air and catching northerly tailwinds to cover up to 80 miles a day on a 3,000 mile journey. During the day they travel alone but keep an eye out at night when they gather in trees to form roosts, a key indicator of migrating monarchs. Journey North is a project where you can help submit sightings near you which helps monarch researchers.