Friends of Mission Bay Marshes

What is a marsh?
    A marsh is a type of wetland that generally has soil inundated with water year round. Coastal marshes are a combination of aquatic, semi-aquatic, and terrestrial habitats characterized by herbaceous plants and aquatic grasses. Many of California's coastal marshes exist where freshwater streams flow into the ocean, and thus have a mix of fresh and salt water, called brackish water. The plants and animals that inhabit these brackish environments have unique adaptations, and thus many are found in no other habitat type. California's coastal marshes can be composed of as many as five micro-habitats with a gradation in salinity, and thus are extremely bio-diverse.

What types of marshes comprise the wetlands of Mission  Bay?
     Mission Bay is an estuary with brackish marshes at some of its shores. The bay is also made up of eel-grass beds, mudflats, and sandy bottom shallow water habitats. So it is important to note that the marsh is one habitat type within the wetland that is Mission Bay. And within the marsh habitat there occurs zonation, which is a gradation of inundation of water, salinity, and the associations of flora and fauna.

What types of plants support the marshes of Mission Bay?
     Marsh plants, or marsh flora, are a diverse assemblage of organisms. Most are herbaceous, or soft-stemmed, and include succulents and grasses. Most are adapted to an aquatic or semi-aquatic and saline habitat. At least 56 species from 22 families have been described within the Kendall-Frost property alone. Some of these species are non-native, or invasive, however all contribute to the ecology of the habitat. Dominant species include cord grass, pickleweed, saltwort, and saltgrass. To review a species list, click HERE.

What species of birds use the marshes of Mission Bay?
    Only a relatively few bird species are residents of the marshes of Mission Bay. Perhaps the most noted is the California light-footed clapper rail (pictured right) which has been recognized as endangered since the inception of the formal lists in 1970 of the Endangered Species Act of 1973. Migratory and visitor species comprise the majority of bird species described in the marsh. Residents and visitor include ducks, cormorants, herons, hawks, plovers, hummingbirds, and of course, the clapper-rail. At least 144 species from 38 families have been described within the marshes of Mission Bay. To review a species list, click HERE.

What other animals inhabit the marshes of Mission Bay?
     Fish, crabs, snails, beetles and flies are just some of the resident fauna that comprise the food web of the marsh. Rabbits and mice are becoming common visitors to the habitat, while relatively recent predators include opossums, crows, and domestic cats, which particularly threaten resident birds by consuming their eggs. Additionally there are algal species and a host of fungal and bacterial decomposers that play integral roles in the recycling of nutrients within the marsh habitat.

What are the functions of Marshes?
     Marshes provide critical functions not only for the local environment but for humans as well. Marshes act as a filter, absorbing nutrients from stream flow that otherwise cause adverse affects in coastline environments, they slow shoreline erosion from continual tidal flow and storm surges, and they provide food sources for migratory animals. Aesthecially they offer a unique opportunity to observe a great diversity of life.

Why should we protect, preserve, and restore California's marshes?
     As described above, marshes consist of variable habitat and thus support a great diversity of life. Primarily, only about 5 percent of coastal California's indigenous marshes remain, mostly as a result of development by humans along the coast. Most of the plants and animals that once inhabited these wetlands did not and do not occur in any other habitat type. Secondly, coastal California is part of the Pacific Flyway, one of four principle bird migration routes in North America. As noted above, the marshes of Mission Bay host mainly migratory bird species. These stopping grounds are thus critical. For more information, consult the Sources and References listed below.