Suisun Marsh

The marsh is home to many species of birds and other wildlife, and is formed by the confluence of the Sacramento and San Joaquin rivers between Martinez and Suisun City, California and several other smaller, local watersheds.

In an effort to maintain the wetlands, the marsh landowners sought legislation to preserve the area from residential or commercial development.

RREC is an all volunteer, non-profit organization that offers an educational program to 3rd and 4th grade students who visit the ranch on field trips.

[citation needed] Another public part of the marsh is Grizzly Island Wildlife Area which is managed primarily for waterfowl, although over 230 species of birds have been seen here as well as many mammals, amphibians, reptiles, and fish.

Grizzly Island has an unusually dense population of river otters, which can be seen swimming in its numerous sloughs, ponds, and roadside ditches.

While this system is still in use on the Sacramento-San Joaquin Delta islands to the east, it failed in the Suisun Marsh due to unacceptably high soil salinities.

Portions of the marsh were subsequently converted from farming to permanently and seasonally flooded wetlands in the twentieth century.

The rest of the year, the ponds are flooded and drained on a schedule designed to optimize conditions for plants which provide seeds preferred by waterfowl, namely alkali bulrush, fat hen, and brass buttons.

When Suisun agricultural lands reverted to wetlands, they provided habitat for waterfowl displaced decades earlier by reclamation.

The wetland managers for both the private hunting clubs and the state's public land take water from major and minor sloughs throughout the marsh.

The gates span Montezuma Slough near the Roaring River intake and are periodically operated from October to May to meet the more recently established salinity standards set by Decision-1641, to block the salty flood tide from Grizzly Bay but allow passage of the freshwater ebb tide from the mouth of the Sacramento-San Joaquin Delta.

And is an important area for native fishes including the delta smelt which is protected by the federal Endangered Species Act.

[7] The Suisun thistle is perennial and stays in its juvenile stages of life until it is ready to flower and once the rosette reaches its mature phase it can take up to a year or more to develop the leafy stem.

Suisun Marsh
Mount Diablo as seen from the Suisun Marsh:
Schedule for flooding ponds during the fall hunting season, then leaching, and finally drying them during the summer.
Montezuma Slough, to the north and east of Grizzly Island, is the key to wetland management.
Suisun Marsh Salinity Control Gates, open to allow freshwater into the Montezuma Slough.