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COASTAL WETLANDS IN ORANGE COUNTY

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Clipboard researched by Rick VanderKnyff / Los Angeles Times

Coastal wetlands include a number of natural communities that share the unique combination of aquatic, semi-aquatic and terrestrial habitats resulting from periodic inundation by tidal waters, rainfall or runoff.

Most of California’s coastal wetlands--including Anaheim Bay, Bolsa Chica and Upper Newport Bay in Orange County--are estuarine salt marshes with associated tidal channels and mudflats, formed where freshwater streams meet the sea. Freshwater marshes, such as the San Joaquin Marsh in Irvine, are less

common along the coast. The San Joaquin Marsh is a remnant--along with Upper Newport Bay--of a vast wetlands that once stretched across the San Diego Creek watershed.

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Wetlands provide habitat for a vast array of organisms, including many endangered species. During peak migration periods, hundreds of thousands of birds migrating along the Pacific Flyway descend upon these coastal waters in search of refuge and food. Coastal wetlands also export nutrients and organic material to ocean waters, and harbor juveniles of many fish and

other aquatic species. Wetlands buffer the effects of storms, thereby reducing shoreline erosion, and improve water quality by filtering and assimilating many pollutants from sewage outfalls and agricultural runoff.

Coastal wetlands have suffered greatly from human disturbance. The California Nature Conservancy has estimated that statewide, 80% of coastal wetlands have been lost. Most have been filled, dredged or diked and converted to farms, pastures, harbors, cities and garbage dumps.

SEAL BEACH NATIONAL WILDLIFE REFUGE

Location: Northeast of Pacific Coast Highway, Seal Beach

History: Anaheim Bay was once part of an extensive system of coastal marshes. Farmers began draining the bay’s marshlands in the late 1880s; in 1944, the U.S. Navy acquired 5,000 acres of the bay for construction of the Naval Weapons Station. Oil drilling began in 1954. The 911-acre refuge was established in 1972 in reaction to a proposed freeway through the bay’s remaining marshland.

Description: Although oil drilling continues, the Anaheim Bay marshland receives ample tidal circulation and supports a diverse salt marsh community. The marsh and adjacent mudflats provide foraging and resting grounds for migratory shorebirds and waterfowl. The endangered California least tern and light-footed clapper rail nest here, although their numbers have declined in recent years largely because of predation from non-native red foxes. Recovery efforts are under way.

Access: The refuge is located within the Seal Beach Naval Weapons Station, and there is no public access. Information: (805) 725-2767.

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BOLSA CHICA ECOLOGICAL RESERVE

Location: East of Pacific Coast Highway, south of Warner Avenue, Huntington Beach

History: Bolsa Chica, meaning “little pocket” in Spanish, was originally a 2,300-acre estuary before much of it was drained for farming in the 1890s. In 1899, sportsmen built a dam across outer Bolsa Bay to restrict tidal flow into the marsh, and constructed ponds and levees to facilitate duck hunting. When the outer bay’s opening silted up, the hunters dug a channel into what is now Huntington Harbour. Oil was found at Bolsa Chica in 1920, and roads, drilling pads and pipelines have since been built throughout the lowland. In 1973, the state established the Bolsa Chica Ecological Reserve on 557.5 acres, including outer Bolsa Bay. Tidal flow was restored to 140 acres in 1978, and two nesting islands for endangered California least terns were built.

Description: Habitats within Bolsa Chica include open water, intertidal mudflats and a diverse salt marsh community of pickleweed, saltgrass, jaumea and marsh heather. Endangered Belding’s savannah sparrows live in the pickleweed; herons, terns and endangered California brown pelicans fish for killifish, sculpin and arrow gobies on the open water while shorebirds forage on the mudflats. Above outer Bolsa Bay is a midden known as the Cogged Stone Site, which has yielded more than 400 carved, disc-shaped stones dated to about 2,500 B.C. Cogged stones, whose purpose is unknown, have been found in only two areas in the Western hemisphere: coastal Southern California and central Chile.

Access: A trail with interpretive signs begins at a parking area on the inland side of Pacific Coast Highway between Warner Avenue and Golden West Street, across from the entrance to Bolsa Chica State Beach. A parking lot at Warner Avenue and Pacific Coast Highway provides access to outer Bolsa Bay. Free tours are offered monthly winter through spring by Amigos de Bolsa Chica. Information: (714) 897-7003.

Future: Development planned for Bolsa Chica includes a marina with ocean access, a residential community, parks and an additional 915 acres of restored wetland; local residents and environmental groups are fighting development of the wetlands.

UPPER NEWPORT BAY ECOLOGICAL RESERVE

Location: West of Back Bay Drive, Newport Beach

History: The naturally protected lower bay has been used as a harbor since the late 1800s. Established in 1975 and managed by the state Department of Fish and Game, the ecological reserve protects 752 acres of productive wetland habitat in the upper bay.

Description: Most of the shallow bay is exposed at low tide and consists of intertidal mudflats and an extensive salt marsh community of cordgrass, pickleweed, saltgrass, jaumea and the endangered salt marsh bird’s beak. More than half of the state’s breeding pairs of the endangered light-footed clapper rail make their home here. Stands of rush, cattail, tule and willow occur where freshwater runoff enters the bay, and along portions of the channelized San Diego Creek. The reserve is used extensively by migrating shorebirds and waterfowl.

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Access: Upper Newport Bay is accessible on the west side at North Star Beach, located on North Star Lane off Polaris Drive; there are also overlooks on Galaxy Drive. Backbay Drive, a one-way road that follows the east shore of the bay, provides parking, overlooks and access to a small-boat launch. Free tours are offered monthly winter through spring by Friends of Newport Bay. Information: (714) 646-8009.

SAN JOAQUIN FRESHWATER MARSH RESERVE

Location: Campus Drive near Jamboree Road, Irvine

History: Once part of an extensive wetlands system that included Upper Newport Bay, the San Joaquin marsh has suffered from a variety of human activities. Much of the surrounding wetland was drained for agriculture beginning in the late 1800s. Natural siltation probably created the first barrier between the remaining marsh and the estuarine bay; early builders made the barrier permanent with roadfill for the original MacArthur Boulevard. The dike trapped sediment behind, slowly suffocating the marsh in silt. San Diego Creek was dammed in 1934, adding to the problem. Some flow to the marsh was later restored by duck hunters, but in 1968 the Orange County Flood Control channelized San Diego Creek and cut off the flow of surface water. As a result, the marsh gained salt through evaporation and began losing its vital areas of open water as vegetation grew unchecked by the scouring action of floods. The Regents of the University of California purchased the marsh in 1970 (with a matching grant from the Ford Foundation) for inclusion in the Natural Reserve System.

Description: Although degraded, the marsh remains a diverse ecosystem that helps support 159 species of plant (54% native), 6 species of amphibian, 16 species of reptile, 24 species of mammal and 212 species of bird (about 50% migratory). Habitats include freshwater marshlands, shallow ponds and channels confined by earthen dikes. Dry bluffs are home to a remnant coastal sage scrub community. The marsh now receives some water from shallow wells; efforts to supplement the supply are under way.

Access: No one may enter the reserve without a permit. Information and applications are available through the marsh steward, (714) 856-6006 or 856-6031. Apply at least two weeks in advance.

Sources: “California Coastal Resource Guide” (California Coastal Commission, 1987); University of California Natural Reserve System; U.S. Fish and Wildlife Service; California Nature Conservancy.

LIGHT-FOOTED CLAPPER RAIL: Estimated Number of Pairs

Location 1982 1983 1984 1985 1986 1987 1988 Anaheim Bay 28 20 24 11 5 7 14 Upper Newport Bay 103 112 112 87 99 119 116 San Joaquin Reserve 5 4 1 2 1 0 NA San Joaquin Carlson Road Marsh 5 4 2 0 0 1 NA County Totals 141 140 139 100 105 127 NA State Totals 221 249 277 142 143 178 NA

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NC: No census taken

NA: Not available

Source: U. S. Department of Fish and Wildlife

CALIFORNIA LEAST TERN: Estimated Number of Pairs

Location 1980 1981 1982 1983 1984 Anaheim Bay 38-43 40-45 17-20 4 21-22 Huntington Beach State Park 70-90 105-120 85-111 85-91 68-72 Bolsa Chica (North) 20-26 31-54 70-92 110-116 82-83 Bolsa Chica (South) NC 19-21 8-10 25-30 18-22 Upper Newport Bay 2-5 0 0 9 6 County Totals 130-164 195-240 180-233 233-250 195-205 State Totals 745-793 826-830 469-553 874-919 510-527

Location 1985 1986 Anaheim Bay 20 49 Huntington Beach State Park 45 53 Bolsa Chica (North) 96 60 Bolsa Chica (South) 22 10 Upper Newport Bay 0 13-18 County Totals 183 185 State Totals 607-701 NC

NC: No census taken

Source: U. S. Department of Fish and Wildlife

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