Naturalist Notes

With seven-foot wingspans and giant bills, brown pelicans (Pelecanus occidentalis californicus) are hard to miss as they soar over bodies of salt water. Spotting fish, they can dive at speeds of up to 45 miles an hour, plunging head first, filling their gullets with up to three gallons of water and catch. Removed from the endangered species list in 2009 after decades of restoration efforts, as many as 20,000 individuals spend the summer in the golden state. Before winter, most will head back to warmer southern breeding grounds.  Add your sighting to iNaturalist.

Also called the California horse-chestnut, this multi-trunked deciduous tree can live as long as 300 years. Aesculus californica has adapted well to summer dry conditions, thriving from the central coast to the Sierra Nevada foothills. Striking white flower spikes appear in spring. The show continues when they go to seed–the largest seeds of any non-tropical plant species. But take care, because bark, leaves, fruits, and seeds contain a neurotoxic chemical. Add your sighting to iNaturalist.

Due to a diet high in seeds, California quails wait until many plants have gone to seed before laying eggs; this makes them one of the latest breeding birds in Marin. Young hatch late spring through summer, are born covered in down, and are able to run immediately and follow their parents to food sources. Males guard their mate and offspring during the breeding season, then neighboring families come together to form large flocks in the fall and winter, when multiple males take turns acting as sentries. Add your sighting of Callipepla californica to iNaturalist.

The reverberating noise of a cicada is synonymous with summer. How can a small insect create such mighty sounds? U.S. Naval researchers unlocked the mystery when seeking to discover how to improve underwater communication. Credit the male cicada’s tymbal organ, which has rib-like bands on a membrane that vibrates rapidly when activated by a special muscle. Males do a version of cicada Pilates 300 to 400 times a second! Cicadas don’t bite or sting, are not poisonous, and generally don’t injure garden plants. So leave them be and enjoy the cacophony. Learn more about cicada acoustic research. 

Colorful adult dragonflies grace freshwater ponds and wetlands in summer. Some prefer still water; others like running streams. Look for long, bright blue, green, or orange bodies and delicate wings.  Males do acrobatic maneuvers, patrolling back and forth in search of females, who visit ponds, lakes, and streams to lay eggs. Some species of these insects migrate long distances, and can reach speeds of up to 30 miles an hour in flight. Others are homebodies and travel more slowly. Their favorite summer snack is mosquitoes. Add your sightings to iNaturalist.

Listen for the soft, haunting call of a mourning dove in morning or evening. They are one of the most abundant and widespread bird species on the continent, living comfortably in close proximity to humans. Mourning doves even build their loosely woven nests and raise their young on house gutters, eaves, or windowsills. Males choose favorite cooing perches; regularly advertising territory with their calls. They feed in open ground, preferring seeds, and are easy to attract to a backyard with grains like millet. Add your sightings of Zenaida macroura to iNaturalist.

Pipevine swallowtails are a large, black butterfly with iridescent blue in the males and brown in the females, however, the underside of both reveal bright orange spots which advertise their toxicity. The caterpillar’s only food source, California pipevine, contains aristolochic acid which is sequestered within the caterpillar’s tissues and then retained into adulthood. When females lay eggs, these toxins are transferred to their eggs, protecting them from predation as well – a striking example of the important relationship between butterflies and their host plants. Add your sightings of Lampropeltis californiae to iNaturalist.

Otters have two layers of fur – the thickest coats in the animal kingdom – to keep them warm and buoyant. At home in water or on land, they have webbed feet and sleek tails for swimming as well as strong legs and sleek bellies for running and sliding. They can jog as fast as 15 miles per hour! Creekside dens often have an underwater entrance, helping to protect them from predators. Otters are known for playful antics and a variety of vocalizations from chuckles to chirps to growls. Due to conservation efforts and habitat improvements North American river otter populations have recently rebounded and they are once again found in many parts of the Bay Area. Add your sightings of Lontra canadensis to iNaturalist.

Common in the Bay Area, these dramatically hued butterflies are easy to spot. Look for orange dotted wing tips with a white band fanning against black. Adelpha californica can often be found fluttering near stands of native live oak trees, which are the host plants for their larvae. The oak leaf diet makes them distasteful to predators. Adults are attracted to ripe fruit, flower nectar, and mud puddles, where they drink nutrients from wet soil. Add your sighting to iNaturalist.

Also called blue-bellies, these common lizards grow up to 8 inches long, nose to tail. Males show off by doing pushups, exposing bright blue undersides. They are at home in backyard gardens, sunning on paths, rocks, and fence posts, and snacking on spiders, mosquitoes, and other insects. To regulate body heat, each individual can change color from light gray to near black. A fence lizard can live for several years, hibernating through the winter. The species thrive because each female can lay up to three clutches of eggs each year. So, watch out for the baby lizards that emerge during the warm, dry season. Add your sightings of Sceloporus occidentalis to iNaturalist.