Estuary

The Importance of the Smith Estuary

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The Smith River estuary plays a very important role in the life history of its salmonids. Young fish migrate to the estuary from the fresh water tributaries of the Smith from higher elevations in the watershed. A biologically rich environment, the estuary is where the river reaches salt water creating a mix called “brackish” water. In this environment, their bodies of young fish adapt to salt water and they learn to consume new sources of food and to avoid a new set of predators. This major change causes young salmon to become less active and more vulnerable to predators such as birds and larger fish.

To survive, young salmon must find places to hide and feed. Ocean-bound young salmon may spend days or months in estuaries and near shore waters as they adjust to saltwater and grow, getting ready for an ocean journey. The estuary provides habitat year round for steelhead and is particularly important in summer and fall seasons when the river headwaters and tributaries typically have low stream flows and higher water temperatures that may limit the carrying capacity for larger fish.

In general, restoration on the lower Smith is focused on enhancing riparian vegetation including removal of exotic plant populations, reconnecting existing off-channel wetlands to tidal waters to decrease stranding, removing barriers to fish passage, and creating additional foraging grounds for rearing salmonids.

All plans identify the estuary and lower river as nature’s nursery for salmonids as the most degraded habitat in the entire river ecosystem due to development, road building, and agriculture. Two consensus based planning documents provided guidance for restoration work on the Smith River. Both plans identified the estuary and lower reaches of the Smith river as a high priority targets for restoration. The existing habitat has been degraded and habitat conditions have been simplified in nature’s nursery for aquatic species. The two documents are:

The Smith River Anadromous Fish Action Plan

The Recovery Strategy for California Coho Salmon

Recently published studies confirm the importance of restoration in the Estuary.

BEAVER BANK LODGE USE, DISTRIBUTION AND INFLUENCE ON SALMONID REARING HABITAT IN THE SMITH RIVER, CALIFORNIA

SRA builds consensus among differing local interests including government agencies at every level  and non-profits involved in fisheries work like CalTrout, Native Fish Society, Save-the-Redwoods League, Trout Unlimited and others.

2018 Smith River Coastal Plain Report

Estuaries and riverine habitats along the coastal plain represent a small fraction of a watershed but they play a large role in salmonid productivity throughout the Pacific Northwest. All anadromous fish use the estuaries prior to ocean entry. Low gradient streams, sloughs, backwaters, and off-channel habitats provide low velocity refuge habitats are the habitats that provide food and shelter for rearing juvenile salmonids.

These low gradient areas are also popular locations for human use and development. Like many of the estuaries in the Pacific Northwest, the Smith River estuary has undergone diking, dredging, and road building resulting in reduced quantity and quality of available stream habitat. The Smith River Anadromous Fish Action Plan (SRAC 2002), Recovery Strategy for California Coho Salmon (CDFW 2004), and the Recovery Plan for the Southern Oregon/Northern California Coast Evolutionarily Significant Unit of Coho Salmon (NOAA 2014) all identify the estuary and lower reaches of the Smith River as a high priority for restoration initiatives. However, these plans lack specificity regarding restoration actions needed to enhance the quantity and quality of instream habitat and overall ecosystem function of the estuary and streams in the Smith River Plain.

In partnership with the Del Norte County Resource Conservation District, with a grant from the California Coastal Conservancy, SRA has developed a Restoration Plan for the Smith River Plain. We used recent salmonid monitoring data, historic and present day aerial imagery, fish passage data, topographic information, and landowner and stakeholder engagement to identify and prioritize potential restoration projects. The purpose of the plan is to provide options for multiple ecosystem benefits including improved: salmonid habitat, riparian and floodplain connections, water quality, and overall protect and restore natural channel structure and function.

The final report is now available and can be used by landowners, restoration practitioners, and agency members to advance efforts to improve fish and stream health in the Smith River Plain. Get a copy of the report here.

Morrison Creek Multi-Benefit Project

SRA is working to identify and advance restoration opportunities to reduce impacts of overbank flooding and improve habitat for salmonids in Morrison Creek.

With Prop 1 funds from the California Coastal Conservancy and California Department of Fish and Wildlife, the SRA Team working on the project includes Michael Love & Associates, Inc. who is performing geomorphic and hydraulic evaluations of existing conditions in Morrison Creek and identifying potential restoration actions for the community to consider. SRA is engaged with stakeholders and landowners in this process, which will identify and advance actions resulting in long-term improvements to the channel form and function of Morrison Creek.

The Morrison watershed originates in the steep forested hills east of Highway 101 and tributaries cross an alluvial fan on the Smith River coastal plain before meeting the main stem of the Smith River near the head of the tidal estuary. Downstream of Highway 101, the gravel and cobble dominated stream has reduced channel capacity which has impacted the quality and quantity of instream habitat, reduced fish passage, and increased flooding of the surrounding landscape.

Morrison Creek watershed encompasses 3.64 square miles and contains 6.41 miles of anadromous fish habitat across the mainstem and multiple small tributaries. Spawning gravel and rearing habitat are present throughout the majority of the basin for all four salmonids native to the Smith River, coho salmon, Chinook salmon, steelhead trout, and coastal cutthroat trout.

Stotenberg Creek Fish Passage

SRA’s recent estuary monitoring efforts has shown that Stotenburg Creek provides important winter rearing habitat for juvenile Coho salmon, unidentified trout and Coastal cutthroat trout.

Stotenburg Creek is a small coastal tributary of the Smith River that contains 1.78 miles of potential anadromous fish habitat. The sub-basin originates in the forest upstream of Highway 101 and flows under South Fred Haight Drive to meet the Smith River near the County Public Boat Ramp.

Although the creek typically dries during the summer months it flows during the spring and early winter. Fine sediment dominates the channel with suitable spawning gravels present but rare near Highway 101.

Unfortunately, multiple road crossings along the stream channel limit the ability of fish to migrate in and out of this valuable off-channel rearing habitat. In an effort to address these undersized or failing road crossings and to restore natural channel form and function, SRA has initiated a program to advance stream restoration and habitat enhancement in Stotenburg Creek.

SRA was awarded a grant from the California Department of Fish and Wildlife Fisheries Restoration Grants Program in 2018 to launch a program to remove the fish barriers. SRA is working with Stillwater Sciences to conduct topographic, hydrologic, and geologic surveys on private land that will be used to develop designs for replacement of three undersized and failing culverts, which limit passage of juvenile salmonids and access to Stotenburg Creek.

Yontocket Slough Salmonid Access & Habitat Enhancement

Yontocket Slough is a remnant river channel adjacent to the Smith River estuary, located approximately ten miles north of Crescent City, California. The Yontocket Slough/Tryon Creek system drains into the Smith River estuary approximately 1500 feet from the mouth of the Smith River.

At one time, Yontocket Slough was a bend in the main channel of the Smith River — abandoned over 900 years ago. Historic maps (1856) depict Yontocket Slough as a tidally connected oxbow tributary channel to the Smith River and shows Tryon Creek flowing into Lake Earl rather than the Slough. The Yontocket Slough played a vital role in the life history of juvenile salmonids originating from throughout the Smith River basin.

Fish production within the Slough is severely limited by blocked access and degraded habitat. Culverts at Pala Road block access to salmon, steelhead, and cutthroat trout and have lead to sedimentation of the slough. This sedimentation has facilitated the spread of invasive reed canary grass, which chokes the channel, degrades water quality, and prevents native riparian growth. A fish passage barrier located at the lower end of Yontocket Slough blocks migrating fish and invasive nonnative reed canary grass has colonized much of the slough, stream channel and riparian areas, which has a major impact on riparian vegetation and the stream channel.

A planning document has been developed to identify habitat restoration opportunities and develop restoration alternatives for the portions of Yontocket Slough and Tryon Creek that lie within properties managed by the State of California. The restoration objective will include canary grass eradication and removal of the fish passage barrier. This is a complex project that will involve many seasons of work. The 5.5 mile Yontocket Slough/Tryon Creek system drains into the Smith River estuary approximately 1500 feet from the river’s mouth. The lower 3.5 miles of the slough is a migration corridor for adult fish and contains quality juvenile salmonid rearing habitat. Yontocket Slough plays an vital role in the life history of juvenile salmonids originating from throughout the Smith River Basin.

A fish passage barrier located at the lower end of Yontocket Slough blocks upstream migrating adult and juvenile salmonids at almost all flows. Invasive nonnative reed canary grass has colonized much of the slough, stream channel and riparian areas, which prohibits riparian growth, chokes the stream channel,increases sedimentation, and inhibits the mobility of fish at lower flows. Sediment deposition to the stream channel has filled in pools and greatly contributes to colonization by nonnative riparian vegetation.

Sultan Creek Fish Passage Restoration

Sultan Creek enters the Smith River about two miles downstream of Jedediah Smith Redwoods State Park. Sultan Creek is three miles long and has the potential to support much larger salmonid runs than it does presently. An existing culvert under Highway 197 upstream from the creek mouth is a barrier to fish migration and impedes gravel transport. The objective is to complete the design and planning for replacement of the fish barrier and then replace the culvert.

Sultan Creek enters the Smith River about two miles downstream of Jedediah Smith Redwoods State Park. The creek supports chinook and coho salmon, steelhead and cutthroat trout. Sultan Creek is three miles long and has the potential to support much larger salmonid runs than it does presently. In 1991, 1994 and 2005 boulder and complex LWD structures were installed. Salmonids were observed in following years utilizing the habitat provided by these structures. An existing culvert under Highway 197 approximately .7 miles upstream from the creek mouth is a barrier to juvenile salmonid migration, may impact movement of adult fish, and impedes gravel transport. The proposed project will install two concrete culverts.

New Project Under Development

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