• Tips for Visitors
• Nature

There's always wildlife to be seen at Bolinas Lagoon, a 1,100-acre tidal estuary. Snowy egrets, blackbirds, warblers, and dozens of other bird and animal species live in and around this Marin County Open Space District wildlife preserve. Seasonal avian highlights include ducks in the winter, herons in the springtime, and pelicans in the summer. Between April and June, harbor seals and their pups often appear on Pickleweed Island.

Bolinas Lagoon's diverse wildlife, pristine marshes, and water-snaked mud flats make it one of the richest wetlands within the parks. This bird-watcher's paradise is bordered by the seaside village of Bolinas, Highway 1, and the Stinson Beach sandbar.

Audubon Canyon Ranch is a nonprofit, private, thousand-acre wildlife sanctuary and nature education center on Bolinas Lagoon. During the spring, over a hundred pairs of great egrets and great blue herons nest in the tops of the ranch's redwoods. The adjacent lagoon provides these wading and fishing birds with ample food for their young. The nestlings hatch in May and June, which makes those months the best time for a visit. Several miles of ranch trails are open to the public mid-March through mid-July, including the 0.75-mile, self-guided Harwell Nature Trail; the Bourne Trail, which climbs 1,400 feet to Bolinas Ridge; and the Kent and Rawlings trails, which lead to the rookery overlook. Trail maps are available at the Ranch. Visiting hours are limited, so be sure to phone ahead.

Harbor Seals
As you drive Highway 1 along Bolinas Lagoon, look for harbor seals hauled out on Pickleweed and Kent islands, and on the lagoon's tidal sandbars. Harbor seals have a physiological need to come onshore (haul out) almost daily to rest. They also haul out to give birth and rear their young during the pupping season. Though Bolinas Lagoon is not a major breeding area, 150 or more seals and their pups can often be seen on the lagoon's haul-out spots. The best seal-watching months are April through June. Apart from their smaller size, torpedo shape, and stubby flippers, harbor seals differ from sea lions in two ways: on land, they move, inchworm fashion (sea lions progress on all fours); and they lack the external ear pinnae seen in sea lions.

Invertebrates
A muddy lagoon awash with freshwater runoff and saltwater tides may seem an uncomfortable sort of place to live. Yet a hardy group of organisms called invertebrates thrives in the ooze. These tiny, spineless shrimps, worms, and other creatures regulate their internal salt levels to accommodate constant changes in salinity. The presence of invertebrates is one reason why estuaries are one of the most productive types of ecosystems on the planet.