VIDEO: Jeff Corwin explores the impacts of climate change on monarch butterflies

Autumn is one of the coolest times of year — and I don’t just mean “coolest” as in “brrr.” After all, it’s when we see leaves all over change color and fall, squirrels gather nuts and great flocks of birds head south for the winter.

But if you’re lucky, you’ll see fall’s most enchanting spectacle: 250 million monarch butterflies filling the autumn sky on their annual migration from the eastern United States and Canada to Central Mexico. You can find migrating monarchs in the Great Lakes region, in the Midwest, along the Atlantic and Pacific coasts, and in Texas.

Mysterious migration

Courtesy of U.S. National Park Service

Scientists can neither explain exactly why monarchs migrate, nor say precisely how monarchs navigate the 3,000-mile-long journey — just that the sun keeps them on course.

The monarch’s amazing instincts are also of great interest to researchers. “Migrating monarchs live for eight or nine months, compared to just two to five weeks for monarchs at other life stages,” according to a report in Defenders magazine. Yet they somehow know which direction to go, how high to fly, and other bits of knowledge – perhaps inherited from generations past.

One thing is certain, however, the mystery behind their journey makes it all the more magical.

But monarch migrations may one day disappear. Habitat loss due to logging in Mexico, agriculture,  forest fires and climate change are some of the many threats facing this “regal” butterfly.

How you can help

Become a Defenders’ Wildlife Guardian—your contribution helps save wild animals like monarch butterflies.

Learn more about butterflies.