Monarchs on the Move
1Monarch butterflies have bright orange wings with black lines and white dots. Many monarchs that live in the eastern United States and Canada make a very long trip each year. Map 1 shows where they go.
2The trip south begins in fall, when the days grow shorter and the air turns cool. The monarchs fly during the day and stop at flowers to sip nectar. They are headed toward warmer weather.
3Why do monarchs travel so far? A cold winter would harm them, and the flowers they sip from would be gone. So they fly to the mountain forests of Mexico. There, they rest in thick clusters on fir trees until spring.
4In spring, the monarchs leave the mountain forests and fly north again. They do not fly all the way back. They stop in the southern United States, where milkweed is growing. There, the females lay eggs on the milkweed leaves. The eggs hatch into caterpillars, which eat the leaves. The new butterflies keep flying north. It takes several generations of monarchs to reach Canada again.