Mysteries of the Mud

The flocks of birds you often see on the mudflats of the bay perch on top of a dynamic ecosystem teeming with life. A single handful of Bay mud can contain over 40,000 organisms! These organisms are the result of the tidal system that pulls ocean water into the Bay twice daily, depositing decaying organic matter that the invertebrate and bacterial communities in the mud need to survive. This dynamic system of nutrient delivery makes mudflats and wetlands like those found in the Bay some of the most productive ecosystems on earth!

Community Action

The Palo Alto Baylands is one of the only wetland areas in the South Bay that was spared from development. Lucy Evans, Harriet Mundy and Emily Renzel are three community members who worked tirelessly to protect the area and now have local landmarks bearing their names.

Now Save The Bay volunteers plant native species in the park in partnership with the Palo Alto Open Space District. Thanks to the efforts of these local citizens, tens of thousands of native plants have been planted in the park since 2003. Sign up to volunteer with us today!

Bay 101

For thousands of years, more than 25,000 Ohlone and Miwok people populated the Bay, and wetlands covered over 200,000 acres. Beginning during the Gold Rush, about 90% of these wetlands were destroyed. The Bay’s remaining wetlands perform the following services to bay area residents:

  • Filter the bay’s water, helping reduce the impacts of urban runoff.
  • Protect communities from floods and sea level rise by absorbing water from rainstorms and high tides.
  • Provide habitat for 400 species of wildlife including 105 threatened and endangered species such as the California Clapper Rail and the Salt Marsh Harvest Mouse.
  • Provide open space and recreation for bay area residents.
Click Critter Icons on the Map to Learn More!
Intact Transition Zone Pickleweed Dragonfly Fox Fish Marsh Hawk

A Window Into the Past

While San Francisco Bay has lost around 90 percent of its wetlands, it has lost a higher percentage of its wetland transition zones or ecotones. Tidal marsh ecotones, referred to here as simply ecotones, are the areas where tidal marshes meet upland areas. Save The Bay focuses on restoring this zone, and like other people practicing restoration around the Bay, we look to the remaining ecosystems to help inform our restoration projects. Historically, these ecosystems would have stretched over miles and provided continuous habitat for creatures that use the wetlands. China Camp provides us with a reference for restoration at other sites.

Cultural History

Chinese fishermen began fishing for shrimp in California probably around the mid-1860s. As the enterprise grew in the 1870s and 1880s, numerous villages or "shrimp camps" were established on the shores of both San Francisco and San Pablo Bays. China Camp was one of the largest and longest-lived of these camps. Records indicate that the village had three general stores, one marine supply store, and a barber shop. Shrimp fishing was a long-established industry in China, and many immigrant Chinese arrived with knowledge of fishing and preservation techniques necessary to develop a shrimping enterprise in California.

*From the National Park Service

Bay 101

For thousands of years, more than 25,000 Ohlone and Miwok people populated the Bay, and wetlands covered over 200,000 acres. Beginning during the Gold Rush, about 90% of these wetlands were destroyed. The Bay’s remaining wetlands perform the following services to bay area residents:

  • Filter the bay’s water, helping reduce the impacts of urban runoff.
  • Protect communities from floods and sea level rise by absorbing water from rainstorms and high tides.
  • Provide habitat for 400 species of wildlife including 105 threatened and endangered species such as the California Clapper Rail and the Salt Marsh Harvest Mouse.
  • Provide open space and recreation for bay area residents.

Hydrology

In the middle of nineteenth century, San Francisco Bay maps show massive expanses of tidal saltwater marshes along the East Bay shoreline, but no sign of Arrowhead Marsh. In the late 1860’s, during the construction of the Lake Chabot Reservoir, strong rains and flood conditions caused a massive failure in the new earthen dam. Not long after that breach, maps of the area indicate the existence of a small pointed plot of land jutting out from the Oakland shoreline. Local ecologists now believe that the existing marsh is a direct result of that flood.

Birds of the Bay

Each year, millions of birds pass through the Bay as a stop on the Pacific Flyway. Over 300 species have been documented in the Bay. The bay attracts birds due to its abundant mudflats and tidal marshes and its protection from the waves and winds of the Pacific Ocean. Many birds, such as the endangered white pelican, the eared grebe and the forester’s tern stop here to feed and regain their strength before completing their migration.

Bay 101

For thousands of years, more than 25,000 Ohlone and Miwok people populated the Bay, and wetlands covered over 200,000 acres. Beginning during the Gold Rush, about 90% of these wetlands were destroyed. The Bay’s remaining wetlands perform the following services to bay area residents:

  • Filter the bay’s water, helping reduce the impacts of urban runoff.
  • Protect communities from floods and sea level rise by absorbing water from rainstorms and high tides.
  • Provide habitat for 400 species of wildlife including 105 threatened and endangered species such as the California Clapper Rail and the Salt Marsh Harvest Mouse.
  • Provide open space and recreation for bay area residents.

Trash Trivia

The urban surroundings of Damon Marsh make it a hotspot for pollution. Water from the communities surrounding the Bay runs off into storm drains, which empty directly into the Bay. A wide range of material, from microscopic heavy metals such as mercury to fast food bags to airplane tires are filtered out by the Bay’s marshes. Some of the biggest positive impacts you can have on the Bay are picking up litter in your community, washing your car at a car wash to reduce heavy metal deposition, and keeping your car tuned up to prevent harmful fluids from leaking into the Bay.

Urban Environment

Given that it is surrounded by the Oakland Coliseum, Highway 880 and the Oakland Airport, the Martin Luther King Jr. Regional Shoreline is an unlikely place to find high levels of biodiversity. However, it hosts thousands of birds, including one of the largest populations of the endangered California clapper rail in the world. It is a rare urban wildlife island that attracts thousands of visitors per year to its hiking trails, picnic areas and excellent bird watching opportunities.

Bay 101

For thousands of years, more than 25,000 Ohlone and Miwok people populated the Bay, and wetlands covered over 200,000 acres. Beginning during the Gold Rush, about 90% of these wetlands were destroyed. The Bay’s remaining wetlands perform the following services to bay area residents:

  • Filter the bay’s water, helping reduce the impacts of urban runoff.
  • Protect communities from floods and sea level rise by absorbing water from rainstorms and high tides.
  • Provide habitat for 400 species of wildlife including 105 threatened and endangered species such as the California Clapper Rail and the Salt Marsh Harvest Mouse.
  • Provide open space and recreation for bay area residents.

Salt Pond History

Beginning with Ohlone tribes gathering salt from naturally occurring salt pannes, salt harvesting has been a part of the Bay’s ecosystems. In 1853, Captain John Johnson used levees at Eden Landing to create evaporation pools in shallow, salty areas. This began the modern era of salt evaporation in the San Francisco Bay, and over the next century, tens of thousands of acres were surrounded by levees, cutting off direct tidal influence and converting wetland and mudflat into salt evaporation ponds.

Landscapes In Transition

Unlike other types of bayfill, which support homes, businesses and public spaces, the Bay’s salt ponds provide an excellent opportunity to reclaim former wetland areas. The South Bay Salt Pond Restoration Project currently oversees the transition of 15,100 acres from salt pond to managed habitat, making it the largest wetland restoration project on the West Coast. Restoration starts on a large scale, with construction workers using heavy machinery to shape the ponds. Native low marsh species like pickleweed come in with the tide, and volunteers plant species above the tide line to finish the cycle.

Bay 101

For thousands of years, more than 25,000 Ohlone and Miwok people populated the Bay, and wetlands covered over 200,000 acres. Beginning during the Gold Rush, about 90% of these wetlands were destroyed. The Bay’s remaining wetlands perform the following services to bay area residents:

  • Filter the bay’s water, helping reduce the impacts of urban runoff.
  • Protect communities from floods and sea level rise by absorbing water from rainstorms and high tides.
  • Provide habitat for 400 species of wildlife including 105 threatened and endangered species such as the California Clapper Rail and the Salt Marsh Harvest Mouse.
  • Provide open space and recreation for bay area residents.

Voices from the field

" Community-based restoration means to me that the community does as much as they can to restore the land back to the way it used to be. I can see myself continuing to be a voice for protecting the San Francisco Bay because the little small things that people do affect our environment and wildlife, which ultimately affects us. "
12th Grade Student,
Emery Secondary School