Monarch Butterfly landing on a flower

Expect to See Fewer Monarchs This Fall Thanks to Habitat Loss, Climate Change

September 16, 2024 | Source: Discover and Share | by The Sophia M. Sachs Butterfly House

Monarch (Danaus plexippus) sightings across the country are expected to be rarer this September and October. Scientists noted a significant drop in migration numbers for the beloved butterflies last year.

Experts point to habitat loss and climate change as major contributors to their significant population decline.

During the long, warm days of summer, adult monarchs’ instincts tell them to fly north and find more milkweed to start the next generation. As fall brings shorter days and cooler weather, they stop reproducing and begin the journey to their overwintering grounds in Mexico. This yearly trek stretches several thousand miles from the Southern Canada to Mexico.

For centuries, millions of monarchs have migrated to Mexico each fall, making stops along the way and delighting communities with their annual visit. At one point, the mass of migrating monarchs even appeared on doplar radars.

Monarch caterpillars only eat milkweed (Asclepias) plants, but adult monarchs feed on flower nectar. Monarchs attempting to migrate need a constant source of nectar during their entire journey.

Asters, goldenrods and other native wildflowers that bloom during the fall months provide this nourishment.