The refuge is one of the only remaining salt marshes in Southern California, which has lost over 90% of its original coastal wetlands.
It serves as a primary breeding ground for the endangered California least tern, the smallest member of the tern family in North America.
The refuge protects the light-footed Ridgway’s rail, a flight-sensitive bird that relies entirely on the dense cordgrass found in these marshes.
Gunpowder Point, the location of the main visitor center, was historically used as a manufacturing site for black powder explosives in the late 19th century.
The refuge is an Important Bird Area (IBA) as designated by the National Audubon Society due to the high density of migratory shorebirds.
The South San Diego Bay Unit includes man-made salt evaporation ponds that have been repurposed into deep-water foraging habitat for sea birds.
The San Diego Bay National Wildlife Refuge protects over 3,000 acres of coastal wetland habitat essential for migratory birds and endangered species. The refuge is composed of two primary units, the Sweetwater Marsh Unit and the South San Diego Bay Unit, linked by the Southern California coastal ecosystem. The Sweetwater Marsh Unit contains the Living Coast Discovery Center, which serves as the primary environmental education facility for the refuge. The site is a critical stopover on the Pacific Flyway, supporting species like the light-footed Ridgway’s rail and the California least tern. Much of the habitat consists of restored salt marshes and mudflats that filter runoff and provide nurseries for native marine life. Public access is largely concentrated around Gunpowder Point and the Otay River estuary. The refuge functions as a vital buffer between urban development in Chula Vista and the open waters of the bay. It remains a managed conservation area primarily focused on habitat restoration and wildlife protection.
The elevated boardwalks overlooking the Sweetwater Marsh during golden hour.
Bring high-quality binoculars, as the best birding spots are often set back from the main walking paths to minimize wildlife disturbance.
Check the tide charts before visiting, as the visibility of shorebirds and marine life is significantly better during low tide when mudflats are exposed.
Wear layers, as the proximity to the bay often results in significant temperature drops and wind shifts throughout the afternoon.
Do not attempt to access the fenced-off restoration areas, as these are critical nesting zones for endangered birds.
The Living Coast Discovery Center within the refuge periodically updates its operating days; check for local site closures before planning your trip.
Stay strictly on designated trails to protect fragile nesting habitats; dogs must be leashed at all times.
