In our last post on the California Delta, we mentioned that it’s been called the heart of the California water system. It’s also a diverse ecosystem unto itself. The Sacramento-San Joaquin Delta was once a vast tidal marshland and inland estuary. The Suisun Marsh is the largest brackish water marsh on the West Coast at the Delta’s western most edge. The Delta and the Suisun Marsh have been described as one of the most biologically productive areas in the state, not just for fish, but for otters, birds, and invertebrates.
From sturgeon to salmon, there are over 50 species of fish. Some are native to the waters of the Delta, and some are invasive species brought into the ecosystem. The species invading the Delta are as distant as Siberian prawns from China, or even jellyfish native to the Black Sea. Most of the invasive species come into the estuary through ship ballast water.
The California Delta’s ecosystem is complex and constantly changing. There are species no longer to be found in the waters of the Delta, either due to fishing or invasive species, or pumping water for use further south in the state. You can listen to CAP’s full report on the Delta ecosystem and water usage here.