Dragonflies and Damselflies

White Belted Ringtail Dragonfly
Photo by Paul G. Johnson II.

The Dragonfly and Damselfly Journey at Pinnacles

Although Pinnacles National Park may seem like a vast arid landscape, a closer look reveals water sources like streams, springs, ponds, and the Bear Gulch Reservoir that sustain abundant life. In 2001, park biologists initiated a two-year project to inventory the aquatic macroinvertebrates of Pinnacles, aiming to identify every visible species of worm, snail, crustacean, arachnid, and insect living in or near water.

One prominent group is the dragonflies and damselflies, collectively known as odonates. These insects, easily spotted around fresh water, include 24 species of dragonflies and 16 species of damselflies identified at Pinnacles so far, with more likely to be discovered.

Life and Behavior of Odonates

Adult odonates are efficient predators, using their excellent eyesight and agile flight to capture insects. Their wings beat in opposite directions, granting them superior maneuverability, and they rank among the fastest flying insects. Despite their short adult lifespan, usually a few weeks, odonates are active, spending time feeding, resting, and engaging in reproductive activities.

Males often patrol or guard territories, while females lay hundreds or thousands of eggs in various locations such as shallow streams, plant stems, or moist soil. After mating, males may guard the female to prevent other mating attempts as she lays her eggs.

The young, called naiads, are aquatic, wingless, and look very different from adults. Naiads are also predators, preying on small invertebrates, fish, and tadpoles. They may live among aquatic plants, burrow in mud, or camouflage themselves in leaves on the pond bottom.

Observing Odonates at Pinnacles

Visitors can observe naiads in shallow waters or spot the exoskeletons left behind by those transforming into adults. Watching an adult emerge from its exoskeleton is a delicate process, so patience is key. Adult odonates’ aerial acrobatics offer hours of entertainment, and their bright colors make species identification fun. With practice, it’s possible to observe their behavior, such as chasing prey, laying eggs, or patrolling territories.

If you see a species at Pinnacles that is not on the Pinnacles Dragonfly Checklist, please let us know as soon as possible so that we can attempt to confirm the sighting. Give us information on date, time, location, and habitat. Include a photograph if possible. You may give the information to a park ranger or contact Paul Johnson at (831) 389-4486 ext. 4271 or e-mail us. Please remember that in order to protect the odonates and other natural features of Pinnacles National Park, no collecting is allowed.

References

Biggs, Kathy. Common Dragonflies of California, A Beginner’s Pocket Guide. Azalea Creek Publishing, 2000.
Dunkle, Sidney. Dragonflies Through Binoculars, A Field Guide to Dragonflies of North America. Oxford University Press, 2000.
Manolis, Tim. Dragonflies and Damselflies of California. University of California Press, 2003.
Merritt, Richard, and Kenneth Cummins (Eds.). An Introduction to the Aquatic Insects of North America. Kendall/Hunt Publishing Company, 1996.

Related Information

California Dragonflies and Damselflies