Tag Archives: Institute for Applied Ecology

Study Shows 74 Percent Loss Of Columbia Tidal Wetlands, 85 Percent Up And Down West Coast

THE FOLLOWING IS A NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION STORY

An unprecedented survey has revealed the loss of about 85 percent of historical tidal wetlands in California, Oregon, and Washington. The report, published in PLOS ONE, also highlights forgotten estuary acreage that might now be targeted for restoration.

Where West Coast rivers reach the sea, estuaries serve as critical nurseries for juvenile salmon and steelhead as they make the transition from freshwater to the ocean. They are among the most dynamic and productive habitats known, also supporting migratory birds and a variety of other fish, shellfish, and terrestrial wildlife.

A FEDERAL GRAPHIC SHOWS THE AMOUNT OF TIDAL WETLANDS UP AND DOWN THE WEST COAST, INCLUDING IN SOME OF THE REGION’S MOST IMPORTANT SALMON SYSTEMS. (NOAA)

A team of scientists applied new technologies and data to identify and estimate the historic reach of nearly 450 West Coast estuaries. Their results show that the estuaries historically extended far beyond where they exist now. More than a century of development has erased roughly 85 percent of original vegetated estuarine wetlands, especially around major river deltas.

San Francisco Bay has lost about 85 percent of its original vegetated tidal wetlands, the study found. The Columbia River estuary has lost about 74 percent. While other scientists have estimated losses for these and other well-studied estuaries, this is the first time researchers have applied consistent methods across all 450 estuaries of the contiguous U.S. West Coast.

Mapping Reveals Restoration Opportunities

“Given how valuable estuaries are to so many different species, it’s important to understand how much they have changed and what that means for fish and wildlife that depend on them,” said Correigh Greene, research biologist at NOAA Fisheries’ Northwest Fisheries Science Center in Seattle and coauthor of the new study.

The lost estuary habitat includes areas that were long ago diked and drained for agriculture, and forested wetlands that had not been widely recognized as estuary acreage, said Laura Brophy, lead author of the study and director of the Estuary Technical Group at the Institute for Applied Ecology in Corvallis, Oregon. Identifying such areas may open new opportunities for restoration of estuary habitat that otherwise might go overlooked.

BEFORE AND AFTER IMAGES FROM THE TILLAMOOK ESTUARY PARTNERSHIP SHOW THE EFFECT OF REMOVING LEVEES AND TIDE GATES NEAR THE MOUTH OF THE TRASK RIVER. (TILLAMOOK ESTUARY PARTNERSIHP VIA NMFS)

“By folding in these areas that may not have been recognized as part of estuaries, we have a better idea of just how important and extensive these estuaries were,” Brophy said. “Now we can see new restoration opportunities that people didn’t realize existed.”

The study’s high-resolution mapping also highlights low-elevation areas at greatest risk of flooding as the sea level rises with climate change. Tidal wetland restoration in these vulnerable areas can re-establish natural processes like sediment delivery. This will help these wetlands remain productive into the future.

Estuaries Once Covered 2 Million Acres

The scientists combined precise elevation mapping known as LIDAR with NOAA water level modeling to establish the extent of tides that define estuary habitat. Based on these maps, they estimated that all West Coast estuaries once covered nearly 2 million acres. This is an area nearly three times the size of the state of Rhode Island.

Scientists have data on the historic and current wetlands in 55 of the larger estuaries. Those estuaries have lost about 85 percent of their original vegetated wetlands. These 55 estuaries represent about 97 percent of historical estuary area on the West Coast, so their losses reflect almost all of the estuary losses.

Since Brophy has studied estuaries for years, she found the losses “dismaying but not surprising.” She said the good news is that fish and wildlife that live in estuaries must be adaptable because of the ever-changing tidal environment. She says “if you give them the chance to move back in, they will literally jump at the opportunity.”

The authors of the study include researchers from NOAA Fisheries’ Northwest Fisheries Science Center, the Institute for Applied Ecology, Pacific States Marine Fisheries Commission, Oregon Department of Land Conservation and Development, The Nature Conservancy, Moss Landing Marine Labs, and Pacific Spatial Solutions. The project was coordinated by the Pacific Marine and Estuarine Fish Habitat Partnership.

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NMFS Shares Salmon Habitat Gains, Flood-threat Reduction From Tillamook Estuary Work

THE FOLLOWING IS A NEWS STORY FROM THE NATIONAL MARINE FISHERIES SERVICE

NOAA’s work with community partners restoring estuary habitat in Tillamook Bay, Oregon is revitalizing tidal wetlands for threatened Oregon Coast coho salmon, and helping reduce flooding in the surrounding communities and farmlands.

The project’s benefits to fish were realized immediately—443 acres of different estuary habitats critical to juvenile salmon are now available, including mud flats, open water with vegetation, marsh and others. Often called “nurseries of the sea,” estuaries offer unique conditions, like slow moving water and tides that bring in nutrients, which keep fish safe and allow them to grow.

BEFORE AND AFTER IMAGES FROM THE TILLAMOOK ESTUARY PARTNERSHIP SHOW THE EFFECT OF REMOVING LEVEES AND TIDE GATES NEAR THE MOUTH OF THE TRASK RIVER. (TILLAMOOK ESTUARY PARTNERSIHP VIA NMFS)

A recently published report also confirms the project’s flood reduction goals were achieved. Shortly after project completion, in October 2017, a flood occurred at the site. Our restoration work resulted in widespread reduction in flood levels and duration including along Highway 101, a key commercial and transportation corridor. In total, about 4,800 acres around the project site showed reductions in flood levels.

This project, like many others we work on, shows how restoring habitat back to its natural functions can help coastal communities be more resilient against severe weather. Nature-based approaches are being shown to provide these, and many other economic benefits, along both the the east and west coasts of the United States.

Almost 90 percent of the Tillamook Estuary’s historic tidal wetlands have been lost to development and agriculture. Like many other species relying on estuary and wetland habitats, loss of these areas is a primary contributor to the decline of Oregon Coast coho salmon.

Additionally, Oregon’s winters bring storm surges, heavy rainfall, and snow melt. Combined with high tides, this often causes flooding in the area. Flood losses in Tillamook County exceeded $60 million from 1996 – 2000.

ESTUARIES ARE IMPORTANT HABITAT FOR COHO SMOLTS ALONG WITH THE YOUNG OF OTHER SALMON SPECIES. (ROGER TABOR, USFWS)

To achieve the mutually beneficial project goals, old levees, fill, and tide gates were removed to create tidal estuary habitat. This functions as a “flow corridor,” allowing flood waters to move freely and quickly away from the town of Tillamook. Now, nearby properties and more than 500 structures are protected from flooding. It’s estimated that $9.2 million in economic benefits will accrue from avoided flood damages over the next 50 years.

The project reconnected hundreds of acres of marsh habitat and restored 13 miles of new tidal channels. This will significantly benefit Endangered Species Act-listed Oregon Coast coho salmon. Historically, more than 200,000 of these salmon would return to Tillamook Bay each year. That number was down to just 2,000 in 2012. This habitat is critical for juvenile salmon to feed and grow, and will help with the broader goal of species recovery along Oregon’s entire coast.

The Southern Flow Corridor Project is the result of tremendous community support and collaboration. NOAA Fisheries’ Restoration Center, within the Office of Habitat Conservation, and the West Coast Regional Office, worked with more than a dozen local, state, federal, tribal and private partners on this effort.

BRYCE MOLENKAMP PREPARES TO NET A SALMON ON TILLAMOOK BAY. (MARK VEARY)

Key partners include the Port of Tillamook Bay, Tillamook Bay Habitat and Estuary Improvement District, Tillamook County, the State of Oregon, FEMA, U.S. Fish and Wildlife Service, the Institute for Applied Ecology, and the Tillamook Estuaries Partnership. We provided funding for the project through the Community-based Restoration Program and the Pacific Coastal Salmon Recovery Fund, and on-the-ground technical assistance.