A slough ( / s l uː / or / s l aʊ / ) is a wetland , usually a swamp or shallow lake , often a backwater to a larger body of water. Water tends to be stagnant or may flow slowly on a seasonal basis.
31-1079: Georgiana Slough , is a slough within Sacramento County, California . It is located in the Sacramento–San Joaquin River Delta , and links both the Sacramento River and the San Joaquin River above their confluence in the Delta near Pittsburg , at the head of Suisun Bay , through its connection with the Mokelumne River . The entrance to the slough on the Sacramento River is just below Walnut Grove , at 38°14′21″N 121°30′59″W / 38.23917°N 121.51639°W / 38.23917; -121.51639 and runs between Tyler Island and Andrus Island to where it has its confluence with
62-537: A $ 3.9 million federal stimulus grant . The project was a collaboration among the California Coastal Conservancy , David and Lucile Packard Foundation , DFG, Ducks Unlimited , Elkhorn Slough Foundation, NOAA, URS Corporation , and the U.S. Environmental Protection Agency The Tidal Marsh Restoration Project has been progressing since 2010. Most other Elkhorn salt marshes are projected to be drowned within 50 years. An elevated marsh plane
93-657: A Visitor Center and volunteer opportunities. The nearby Moss Landing Wildlife Area protects 728 acres (295 ha) of salt ponds and salt marsh. Limited recreation is permitted within the Wildlife Area. Harvest of finfish (by hook-and-line only) and clams are allowed within the conservation area only. Clams may only be taken on the north shore of the slough in the area adjacent to the Moss Landing State Wildlife Area. The California Office of Environmental Health Hazard Assessment has issued
124-459: A host of other wildlife from the water is an experience that provides a unique perspective of how the slough is used by the native inhabitants. People are encouraged to keep at least 100 feet of distance between them and wildlife on the slough. The Elkhorn Slough National Estuarine Research Reserve and Elkhorn Slough Foundation provide on-site management, education, and stewardship and offer public access via 5 miles (8.0 km) of trails, as well as
155-547: A part of an endangered environment: wetlands. They act as a buffer from land to sea and act as an active part of the estuary system where freshwater flows from creeks and runoff from the land mix with salty ocean water transported by tides. Restoration is a big effort in California wetlands to restore slough and ridge landscapes. Examples of restoration projects on slough landscapes include The Elkhorn Slough Tidal Wetland Project, Dutch Slough Tidal Restoration Project, and
186-459: A river over time. The development of this landscape is thought to occur by the preferential formation of peat in bedrock depressions. Multiple of these deposits mounted on top of the surrounding bedrock can become elongated alongside the slough and create flow diversions within the system. Different rates of this peat accumulation could be triggered by variations in microtopography that alter plant production and vegetation type. Water flow might be
217-559: A safe advisory for any fish caught in Elkhorn Slough due to elevated levels of mercury and PCBs. In addition, there is a notice of "DO NOT EAT" for leopard sharks and bat rays for women 18–45 years old and children 1–17 years old. California’s marine protected areas encourage recreational and educational uses of the ocean. Activities such as kayaking, diving, snorkeling, and swimming are allowed unless otherwise restricted. The Moss Landing Harbor District has jurisdiction over
248-399: A study done on Elkhorn Slough in California the mean prey richness for fish was greatest near the ocean and lowest inshore. This allows for a higher availability of food to enhance the function of inshore habitats and emphasizes the importance of invertebrate prey populations and how they influence plant production. Birds also inhabit sloughs, making them hotspots for birdwatching , with
279-430: Is a channel in a wetland . Typically, it is either stagnant or slow flowing on a seasonal basis. Vegetation patterns in a slough are largely determined by depth , distribution, and duration in the environment. Moreover, these same variables also influence the distribution, abundance, reproduction, and seasonal movements of aquatic and terrestrial life within the sloughs. Sloughs support a wide variety of plant life that
310-864: Is adapted to rapidly changing physical conditions such as salinity , oxygen levels and depth. In general, sloughs are microhabitats high in species diversity. Open water sloughs are characterized by submerged and floating vegetation which includes periphyton mats dominated by sawgrass typically. The topographical and vegetation heterogeneity of ridge and slough landscape influences the productivity and diversity of birds and fish adapted to that wetland . Fish that typically inhabit sloughs include tidewater goby, California killifish , mosquitofish , and topsmelt . Food habits of fish within sloughs consist of preying upon invertebrates ; mostly epifaunal crustacean followed by epifaunal and infaunal worms and mollusks. Fish can feed on zooplankton and plant material. Research on prey species for fish in sloughs found that in
341-661: Is being created at Hester Marsh to establish a functional salt marsh ecosystem. As specified by the Marine Life Protection Act, select marine protected areas along California’s central coast are being monitored by scientists to track their effectiveness and learn more about ocean health. Similar studies in marine protected areas located off of the Santa Barbara Channel Islands have already detected gradual improvements in fish size and number. More than 8,000 acres (3,200 ha) of
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#1732773284992372-978: Is home to California's greatest concentration of sea otters , as well as populations of endangered Santa Cruz long-toed salamander and the threatened California red-legged frog . The population of sea otter living in Elkhorn Slough reflect that the species is well-adapted for estuarine habitat, and may be a model for the historical sea otter populations now extinct in San Francisco Bay . Elkhorn Slough hosts year-round residents tightly associated with estuaries, such as pickleweed , eelgrass , oysters , gaper clams , and longjaw mudsuckers , as well as important seasonal visitors such as migratory shorebirds, sea otters, and sharks and rays. Habitat types include mudflats, tidal creeks and channels. Other vegetative species include such wildflowers as yellow mariposa lily, Calochortus luteus . Conservation groups have worked to remedy indirect harm from human activity in
403-695: Is prohibited. It includes the waters below mean high tide within Elkhorn Slough lying: The Elkhorn Slough State Marine Conservation Area (SMCA) covers 0.09 square miles (0.23 km ). It includes the waters below mean high tide within Elkhorn Slough: The SMR and the SMCA were both established in September 2007 by the California Department of Fish and Wildlife (CA−DFW). It was one of 29 marine protected areas adopted during
434-757: The Moss Landing Harbor District and the Monterey County Parks Department The Moss Landing Wildlife Area protects the land north and west of the Slough. The Moro Cojo Slough State Marine Reserve just south of Elkhorn protects a similar wetland area. Along with hiking and bird watching, kayaking and stand-up paddle boarding are popular activities on the slough. Watching sea otters , sea lions, seals, brown pelicans , American avocets , cormorants , egrets , terns and
465-587: The Elkhorn Slough Foundation. The Foundation already managed conservation on these parcels. The Elkhorn Slough State Marine Reserve (SMR) covers 1.48 square miles (3.8 km ). The SMR protects all marine life within its boundaries. It is managed by the California Department of Fish & Wildlife (CA-DFW) in cooperation with the National Oceanic and Atmospheric Administration . Fishing and take of all living marine resources
496-779: The Elkhorn Slough being one of the premier birdwatching sites in the western United States. Over 340 species have been seen visiting, including several rare and endangered species. Bird species seen in sloughs include acorn woodpecker , brown pelican , Caspian tern , great blue heron , great egret , great horned owl , snowy plover , and white-tailed kite . Sloughs are largely influenced by human development such as urban and agricultural expansion , industrial and agricultural practices, water management practices, and humans influence on species composition . Uses of identifying these aspects of human involvement can help to better predict restoration efforts to be made in managing sloughs. Examples of attributes that are affected by human stress upon
527-694: The McDaniel Slough wetland enhancement project. [REDACTED] Wetlands portal Elkhorn Slough Elkhorn Slough is a 7-mile-long (11 km) tidal slough and estuary on Monterey Bay in Monterey County, California . It is California's second largest estuary and the United States' first estuarine sanctuary. The community of Moss Landing and the Moss Landing Power Plant are located at
558-658: The Mokelumne River at 38°07′49″N 121°34′40″W / 38.13028°N 121.57778°W / 38.13028; -121.57778 northwest of Bouldin Island just above that rivers confluence with the San Joaquin River. Georgiana Slough was first used by steamboats in the 19th century as a shortcut between Sacramento and Stockton . It is named after the Georgiana , the first steamboat to use
589-672: The Pacific Ocean north of Moss Landing. In 1909 winter storms modified the course of the Salinas River to its present location south of Moss Landing, while Elkhorn Slough persisted as a tributary to the Old Salinas River channel. Construction of jetties at the Moss Landing Harbor in 1946 provided a direct link between the Pacific Ocean and Elkhorn Slough. At this time, salt marshes began to retreat from
620-498: The axis of Elkhorn Slough as it evolved into its present form as a relatively stable estuarine embayment. Carneros Creek is the primary source of freshwater flowing into Elkhorn Slough. McClusky Slough to the north and Moro Cojo Slough to the south also provide freshwater inputs. Elkhorn Slough, one of the largest estuaries in California, provides essential habitat for over 700 species, including aquatic mammals , birds, fish, invertebrates , algae and plants. The slough area
651-407: The environment include periphyton , marsh plant communities, tree islands, alligators , wading birds , and marsh fishes, invertebrates , and herpetofauna . A slough can form when a meander gets cut off from the main river channel creating an oxbow lake that accumulates with fine overbank sediment and organic material such as peat . This creates a wetland or swamp environment. One end of
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#1732773284992682-511: The first phase of the Marine Life Protection Act Initiative, a collaborative public process to create a statewide network of marine protected areas along the California coastline. The Elkhorn Slough National Estuarine Research Reserve is one of 28 National Estuarine Research Reserves established nationwide as field laboratories for scientific research and estuarine education. Additional land protected by
713-427: The key to preventing an accumulation of organic sediment in sloughs due to the fact that accumulation leads to lowering water depths and instead allows for the growth of vegetation. Overall little quantitative data on the degradation of slough landscape exists. Slough and ridge landscape has been greatly degraded in terms of both topographic and vegetation changes over time. Topographical changes create an increase in
744-443: The mouth of the slough on the bay. Elkhorn Slough harbors the largest tract of tidal salt marsh in California outside the San Francisco Bay and provides much-needed habitat for hundreds of species of plants and animals, including more than 340 species of birds. It has been designated as a protected Ramsar site since 2018. The name of the slough derives from the native tule elk Cervus canadensis nannodes , now extirpated from
775-492: The oxbow configuration then continues to receive flow from the main channel, creating a slough. Sloughs are typically associated with the ridge formations found in their presence. Such a landscape consists of mosaic linear ridges, typically of some sort of grass such as sawgrass ridges in the Florida Everglades , that are separated by deeper water sloughs. Edges of sloughs are layers of sediment deposited by
806-643: The region in addition to preventing direct damage to the ecosystem by harvest of resources and conversion of land. A steel weir was built in 2010 at the mouth of the Parson's Slough, a fork of the Elkhorn. The weir or "sill" is intended to reduce the excess erosion of the marsh caused by the dredging of the Moss Landing Harbor and the redirection of the Salinas River . Primary funding came from
837-539: The region. Elkhorn Slough occupies the western reaches of Elkhorn Valley, a relic river valley eroded by drainage pouring out of the Santa Clara Valley and/or Great Valley of California (before the Golden Gate opened) into Monterey Bay during the early Pleistocene. In the mid-1850s A.D. Elkhorn Slough was a minor tributary to the much larger Pajaro-Salinas River system which shared a common entrance to
868-546: The relief between ridge crests and slough bottoms. Vegetation changes consist of an increase in the amount of dense grass and decrease in the area of open water, creating a blurring of the directional ridge and slough pattern. Historical everglade and slough landscape has been greatly affected and degraded by human activity. Open water sloughs support important ecological functions that have been seen to be sensitive to hydrologic and water quality problems stemmed from human activities. Sloughs are ecologically important as they are
899-401: The river's source. In the Sacramento River , Steamboat Slough was an alternate branch of the river, a preferred shortcut route for steamboats passing between Sacramento and San Francisco . Georgiana Slough was a steamboat route through the Sacramento–San Joaquin River Delta , from the Sacramento River to the San Joaquin River and Stockton . A slough, also called a tidal channel,
930-554: The route in April 1850., Slough (hydrology) In North America, "slough" may refer to a side-channel from or feeding a river, or an inlet or natural channel only sporadically filled with water. An example of this is Finn Slough on the Fraser River , whose lower reaches have dozens of notable sloughs. Some sloughs, like Elkhorn Slough , used to be mouths of rivers, but have become stagnant because tectonic activity cut off
961-599: The watershed's 45,000 acres (18,000 ha) are protected under a mosaic of private and public ownership. The nonprofit Elkhorn Slough Foundation is the single largest land owner in the watershed, with nearly 3,600 acres (1,500 ha). The nonprofit Nature Conservancy was the first to buy Elkhorn Slough property with the goal to protect the area's habitat and wildlife. The Nature Conservancy started with only 60 acres in 1971 and through gifts and purchases of disjointed parcels, gained over 800 acres (320 ha) by September 2012, when it transferred 750 acres (300 ha) to