California is home to an incredibly diverse range of caterpillar species. These crawling critters may look a bit strange, but they play an important role in our ecosystems and many transform into beautiful butterflies and moths.
In this article, we’ll take a look at some of the most common and unique caterpillars found across the Golden State.
An Abundance of Species
There are hundreds of different caterpillar species in California. They come in a huge variety of shapes sizes and colors. Some crawl along the ground, while others live in trees. The caterpillars’ diets also vary – some are picky eaters, while others will munch on just about any plant.
According to CaterpillarIdentification.org, there are 76 documented caterpillar species in California. However, there are likely many more that have not yet been identified and added to their database.
Some of the most frequently spotted caterpillars in the state include the monarch, cabbageworm, hornworms, woolly bear, parsley, and swallowtails.
Caterpillar Body Designs
Caterpillars have evolved specialized body designs to help them thrive,
Many species are camouflaged to blend in with their surroundings. The white-lined sphinx, for example, is a bright green color that resembles leaves.
Other caterpillars use mimicry. The two-tailed swallowtail caterpillar has fake eyespots to resemble a snake and scare off predators.
Caterpillars like the woolly bear are covered in hair or spikes. This helps protect their soft bodies.
Brightly colored caterpillars, like the monarch, tip predators off that they are toxic or taste bad.
Fascinating Traits and Behaviors
In addition to their diverse appearances, caterpillars also have many intriguing traits and habits.
Caterpillars are eating machines. A tomato hornworm can consume a whole tomato plant, leaving only the stems!
Some species, like the forest tent caterpillar, build silk nests high up in trees. This helps protect them from predators and weather.
The Hubbard’s silk moth caterpillar can actually glow in the dark due to biofluorescence!
Caterpillars go through a series of molts as they grow. Some, like the mourning cloak, can survive through winter by freezing solid!
Importance to Ecosystems
While caterpillars may damage gardens or agricultural crops, they also play key ecological roles.
Caterpillars help pollinate plants and provide food for birds, small mammals, and other wildlife. Their feces also fertilize soil.
Some species help control invasive weeds. The cinnabar moth caterpillar, for example, keeps ragwort in check.
Encountering Caterpillars
When hiking, gardening, or exploring California’s beautiful outdoor spaces, keep an eye out for crawling caterpillars. Getting a close look at them can be a rewarding experience.
Use caution though – some species have stinging hairs or spikes. Teach kids not to touch fuzzy or bristly caterpillars. Simply observing them from a distance is best.
With so much diversity, there’s always a chance of encountering a new or rare species. If you snap a photo, share it with groups like iNaturalist to help document California’s caterpillar population.
The next time you see one of these crawling insects, take a moment to appreciate the vital role they play in our state’s ecosystems. Their weird and wonderful adaptations allow them to thrive here in California.
Gardening for Butterflies and Caterpillars with California Native Plants, a talk by Susan Karasoff
FAQ
How do I identify my caterpillar?
Look for distinct physical features if the caterpillar has any. Check to see if the caterpillar has a curled tail, head horns, knobs, lashes, spines, or a split tail. These can all be good indicators for certain caterpillar species and will help you narrow down your search rather quickly.
What is the most poisonous caterpillar in California?
Puss Caterpillar (Megalopyge opercularis)
Puss, because this caterpillar is as fuzzy as a kitty; and asp, as in snake, because this is one of the most toxic caterpillars in North America. The venom comes from poisonous spines neatly concealed by the irresistibly fuzzy surface.
What are the spiky caterpillars in California?
The spiny elm caterpillar (Nymphalis antiopa) belongs to the category of “stinging caterpillars.” When full grown, this two-inch-long caterpillar is covered with bristles. Its body is black with numerous white flecks and a row of red spots down the back; the prolegs are red.
Why do I have hundreds of caterpillars in my yard?
Frequent rains have created lush lawns that are ideal for lawn pests, especially caterpillars. Caterpillars have voracious appetites and provide a free mowing service for unsuspecting homeowners.