Migration Cycle of the Painted Lady

Africa to Europe Migration of 10,000 KM; U.S. from Canada to Mexico

Museu De Ciencies Naturals De Granollers presents a fascinating journey of the Painted Lady butterfly from Subtropical Africa to Morocco. Painted Lady are the most widespread butterfly species in the world, and uniquely, their migrations don’t follow a stringent seasonal pattern.

Ever notice a Painted Lady with faded colors, or how about worn down wings? It’s easy to lose perspective of the amazing journey these butterflies take, spanning multiple generations. Click on the graphic below for a high resolution depiction of the Africa/Europe migration.

Painted Lady butterflies (Vanessa cardui) have 6-8 generations per year, with the lifecycle of one generation lasting 1-2 months. Adults live for 3-4 weeks.

The butterflies have numerous natural enemies, including birds, and in the case of the caterpillars, parasitizing wasps. Frogs can also be a predator in some regions.

After their long migrations, many butterflies arrive having lost their bright colors and with broken wings.

U.S. Migration (West Coast)

It’s thought that the Painted Lady migratory patterns are affected by heavy rains like El Nino, which can impact the abundance of larval host plants (in Arizona this includes Arizona Thistle, Desert Cotton, Globemallows, Western Betony, Mexican Sunflower Bush, Yarrow and Western Mugwort).

It can take 6 generations for the complete migration from Mexico to Canada and back, a 9,000 mile journey, with a Northwest migratory path in the Spring and sometimes a second migration back southward in Autumn. The butterflies may fly as much as 12 hours per day, using the sun to figure out the direction.

In addition to the normal challenges that Painted Lady butterflies face in their west coast migration, wildfires are presenting additional challenges. Plants that they normally rely on may have been burned, smoke can block out the sun, and in the event of a really large fire that can create its own weather pattern, strong winds.

Resources:

The Incredible Migration of the Painted Lady (between Africa and Europe)

University of Colorado Boulder, Painted Lady Butterfly

The Washington Post: Weather and wildfires may threaten painted lady butterflies’ migration