By Susan Rothrock Deo Photos by Eva Cicoria
Did you see them? The clouds of butterflies fluttering through Palos Verdes in early spring?
My brother was visiting from out of state and we watched in awe as the stream of butterflies flittered past. I tried taking a picture but none of them stopped long enough for me to even focus on their beautiful wings. They were painted lady butterflies and they were on the move. Most of us know monarch butterflies migrate, the longest migration of any insect, 2,500 miles. But did you know they aren’t alone? Painted ladies migrate, as do other butterfly species like the common buckeye, American lady, red admiral, cloudless sulpher, skipper, question mark, and mourning cloak butterflies. Here are some reasons why. Butterflies can’t handle cold temperatures so some, like the monarch, move to warmer climates in winter.
They migrate to another region where there is more food if there is not enough in their home region. And, when their population grows beyond what their home territory can carry, they migrate to establish new colonies.
Painted ladies are irruptive migrants; they migrate independent of season or other patterns. They don’t migrate in large numbers every year, but this year scientists estimate their migration is in the millions. The abundant rains this winter brought abundant plant growth and a superbloom of flowers in the Southwestern deserts, where the painted ladies reside. With their early start, they have the advantage of being able to feed on the early spring plants first. The butterflies lay their pale green eggs on desert plants. The eggs hatch into grayish brown caterpillars, which gorge themselves on the nectar of about one hundred species of plants. Thistles are their special favorite. Their scientific name, Vanessa cardui, means “butterfly of thistles.” They also like asters, hollyhocks and legumes. When the caterpillars have grown enough, they anchor themselves with a bit of silk, and pupate. Two weeks later they have metamorphosed into a butterfly. The adults are a little smaller than monarchs, with similar, but muted, coloring: dusky orange wings with black spotting, black and white edges. They are part of the “brush foot” butterfly group: they use only four of their six legs, the front two being short and close to their body. The superbloom plants fed lots of caterpillars and produced lots of butterflies. With all that stored energy, the butterflies travel north, some as far as the Pacific Northwest. They fly low, only six to twelve feet above the ground, which is why we have been able to see so many. They can fly up to 25 miles per hour and up to one hundred miles a day.
Another name for these fascinating insects is the cosmopolitan butterfly, because they are the most widely distributed butterfly in the world. They are found on all continents except Australia and Antarctica! I hope you get a chance to see some of these amazing butterflies when you are out on the path—a beautiful creature we share with the world.