Pacific herring are spawning at Point Richmond on the east side of San Francisco Bay, attracting thousands of waterbirds and marine mammals in a feeding frenzy.
San Francisco Bay herring are a critical winter food source for migratory and resident birds, marine mammals, fish, and the whole estuarine ecosystem. Pacific herring are a key reason San Francisco Bay is a hemispheric Important Bird Area and key migratory stop on the Pacific Flyway. During herring spawns, which take place only in the winter and early spring, this food source is one of the most accessible and energy-rich foods available to birds. Fish-eating birds like grebes, loons, and pelicans eat the protein-and-oil-rich spawning fish, and ducks and gulls eat the oil-rich roe.
A couple days ago, we met up with Golden Gate Audubon members and birding trip leaders Tony Brake and Yvonne McHugh to witness the incredible wildlife spectacle. It was a thrill and inspiration for us to see over 700 Surf Scoters, and many thousands of scaup, Bufflehead, teal, Ruddy Ducks, Mew and Glaoucous-winged Gulls, and other birds feasting on the oil-rich herring roe. Days earlier, Cormorants, grebes, Brown Pelicans, and sea lions, gorged on the spawning fish.
It was especially heartening to witness this large spawn considering the herring population has been depressed for the last three years, well under long term averages for the bay population. This was likely due to unusual conditions, including a 5-year drought, and a marine heat wave that ended in 2017. Yet herring have persisted in San Francisco Bay for a millennia, and with help from Audubon and other agencies and organizations supporting a healthy San Francisco Bay, can thrive into the future.
Audubon is working hard to protect herring and the eelgrass and other natural communities herring need to spawn successfully. We have been a co-leader in the development of a management plan for herring in the bay and state that will put in place new regulations to ensure conservative harvest rates for the commercial and recreational herring fishery, while supporting a commercial fleet, one of the last commercial fisheries in San Francisco Bay. Audubon is also leading a campaign to protect eelgrass around the bay, including in Richardson Bay, the heart of herring spawning in San Francisco Bay.
Herring also benefit from the actions of people who live around the bay, and the Audubon network. When you vote for measures like Measure AA - the San Francisco Bay Clean Water, Pollution Prevention and Habitat Restoration Program- and Proposition 68, you are supporting protection of wetlands, shoreline and aquatic vegetation that herring need to survive and thrive. If you are interested in hearing about herring spawns and having a chance to see the incredible wildlife spectacle, you can subscribe to the Department of Fish and Wildlife’s blog and to North Bay Birds or East Bay Birds on Yahoo groups.