Painted Lady Migration Colors the Southern California Skies

Swarms of painted lady butterflies fill the Southern California skies, captivating onlookers as they make their way north for migration. 

There are reports of the butterflies in Temecula, north of San Diego, and in Anza-Borrego Desert State Park, as well as in Pasadena and in the Coachella Valley. 

These painted ladies travel annually from the deserts of Southern California to the Pacific Northwest.

Painted ladies are found on every continent except Antartica and South America. The entire North American population of painted lady butterflies migrates to west Texas and northern Mexico during the winter. 

There are waves of migration as the first generation makes it to northern California and breed, then the next generation makes the trip to the Pacific Northwest, then the following generation will begin making the trip south. 

This year we see a huge increase from previous years, possibly due to the abundant California rains. The sheer number of butterflies this year is the largest its been since 2005, when about 1 billion painted ladies were counted.

Substantial rainfall in the deserts near the Mexican border where the North American painted ladies lay their eggs gives the caterpillars plenty of food. As catepillars, they feed on desert annual plants, including families of mallows, borages, and thistles and their relatives. 

Check out all the painted lady butterflies on the 101 in Encino. Perhaps this is why traffic is moving so slowly. pic.twitter.com/LBVsKa0Cdx

— Jeff Nguyen (@jeffnguyen) March 16, 2019

Front row seats to the painted lady #butterflymigration! #butterflies #paintedladies #Irvine #OrangeCounty pic.twitter.com/4w55GfF8VT

— South Coast Research (@UCSouthCoast) March 12, 2019