Monarchs Migrating

Nature

An orange and black traffic jam is slowly fluttering its way across Texas.

It’s made up of most of North America’s monarch butterflies, headed for wintering grounds in Mexico.

“They come from much of eastern and central North America,” said Chuck Sexton, wildlife biologist at Balcones Canyonland National Wildlife Refuge at Austin. “We have a few that linger here, but most of what we see in Texas is the migration.”

Each fall, tens of millions of monarchs leave their breeding grounds as far north as Canada and start south. Their destination is small wintering areas in the high fir forests of central Mexico.

A Pacific population winters on the Monterey Peninsula of California.

The monarch is especially different from nearly all other insects. Like birds, it has evolved the ability to fly long distances.

In their northern breeding grounds, monarchs live four to six weeks. They lay their eggs on milkweed leaves and the eggs hatch into a green and black caterpillar familiar to most children. The caterpillars feed on the milkweed, spin cocoons and metamorphose into adults.