Organisms+of+the+San+Francisco+Bay+Estuary

Organisms that call the Estuary Home The San Francisco Bay is home to many organisms, some are autotrophs and make their own food and others are heterotrophs, which eat other organisms to survive. The autotrophs are called primary producers because they are the ones everyone relies on. In the San Francisco Bay Estuary, phytoplanktons are the major primary producers. A phytoplankton is a very small plant that floats in water; they include diatoms, algae, and cyanobacteria. In addition, aquatic plants are primary producers such as Pacific Cordgrass, Pickleweed, Gumplant, Saltgrass, Marsh Lavender, Suisun thistle, California Tules, Mason’s Lilaeopsis, Common Reed Grass, and Soft Bird’s Beak which are generally found in the saltmarshes and mudflats of the estuary.

 

 The estuary is also filled with organisms that eat the primary producers called primary consumers. In most cases, the primary consumers in the estuary are zooplankton, which eat the phytoplankton. Some examples of primary consumers are water fleas and tiny opposum shrimp, which are then eaten by larger organisms called secondary consumers. A few secondary consumers are anchovies, herring, shad, and smelt. Lastly, these consumers are eaten by the consumers at the top of the food chain called tertiary consumers and they include river otters, harbor seals or people. 