Biodiversity of Sonoma County

Sonoma County is the largest Bay Area county and its variety of habitats and ecosystems are part of one of the most biologically diverse areas of the world.

FOUR REMARKABLE REGIONS

At Sonoma Land Trust, we approach our work regionally—developing and implementing conservation strategies that are tailored to the unique qualities of the Sonoma Coast, Russian River Watershed, Sonoma Valley and Mountains, and the Sonoma Baylands.

Sonoma Coast Region

The Sonoma Coast is world-renowned for its beauty with a wild and rugged shoreline flanked by marine sanctuaries and dotted with rich estuaries where our rivers meet the sea. The coastline extends from the mouth of the Gualala River at the north down to the Estero Americano at the south. Just inland lies a mosaic of lush redwood and Douglas fir forests, open grasslands, oak woodlands, and unique geological formations developed due to tectonic shifts, volcanoes, and earthquakes.

Click the arrow to learn more about a featured landscape in this region.

Russian River Watershed Region

Only a handful of locations around the world are as rich in biodiversity as the landscape through which the Russian River flows. California’s third longest river stretches from the headwaters in the Laughlin Mountain Range north of Ukiah, to its mouth at the Pacific Ocean near the town of Jenner, traveling south for 115 miles.

Click the arrow to learn more about a featured landscape in this region.

Sonoma Valley / Sonoma Mountain Region

The Sonoma Valley / Sonoma Mountain region is a narrow, 17-mile-long valley framed by the Mayacamas to the east and Sonoma Mountains to the west. It includes over 130,000 acres of wildlands, farms and ranches, vineyards, and communities that are home to over 40,000 people. The prominent scenic and natural features of the region begin with the distinctive Sonoma Valley itself, an extraordinarily productive agricultural area that was the birthplace of California’s wine industry in the 1850s.

Click the arrow to learn more about a featured landscape in this region.

Sonoma Baylands

Serving as the southern gateway to Sonoma County, this area extends along the San Francisco Bay shoreline from Novato to Vallejo, and inland to Petaluma and Sonoma. It was once an expansive mosaic of wetland habitats, including tidal and freshwater marsh and riparian corridors connecting the baylands to the uplands. Fed by the branching estuaries of Novato Creek, Petaluma River, Sonoma Creek and Napa River, the baylands provides habitat to an abundance of species including specialists like the salt marsh harvest mouse that lives nowhere else on earth.

Click the arrow to learn more about a featured landscape in this region.

MEET YOUR NEIGHBORS

Sonoma Coast Region

Along the Sonoma Coast, land and sea come together to form a dynamic ecosystem rich with wildlife. Here you will find the iconic California sea lions, Brandt’s cormorants on the cliffs, ochre sea stars in the tidepools, and blankets of vibrant purple Douglas iris along the hills.

Collage of Sonoma County flora and fauna

Russian River Watershed Region

The Russian River Watershed boasts towering coast redwoods, vibrant wildflowers like western trillium, and wildlife that depend on cool, shallow waterways. Playful River otters and nesting ospreys are often spotted among the diverse riparian system that connects forest, stream, and ocean.

Collage of Sonoma County wildlife and trees

Sonoma Valley / Sonoma Mountain Region

Sweeping oak woodlands and grasslands characterize the Sonoma Valley and Sonoma Mountain Regions, and are home to a wide range of species, including valley oaks, mountain lions, western fence lizards, and the state bird, the California quail.

Sonoma Baylands

The Baylands are home to a range of birds, fish, and marsh vegetation adapted to salty waters. Snowy egrets, white-tailed kites, long-billed curlews, and pickleweed, among others, live in these tidal wetlands and face changing conditions, including rising waters.

BIODIVERSITY’S ROLE IN CLIMATE RESILIENCE

Protecting biodiversity is imperative to building climate resilience in Sonoma County, California, and beyond. As climate change threatens habitats and open spaces, our region risks losing the natural systems that store carbon, safeguard communities from floods and wildfires, and support thousands of interconnected species.

Guided by science, community partnership, and advocacy, Sonoma Land Trust uses nature itself—our most durable and cost-effective climate tool—as a blueprint for action. By conserving and restoring land and water, we strengthen the ecological networks that protect both wildlife and people, ensuring a healthier future for all.