Tag Archives: the nature conservancy

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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Coquille Valley Restoration Work Wraps Up, Win For Fish, Farmers

THE FOLLOWING IS A NATIONAL MARINE FISHERIES SERVICE STORY

Partners representing natural resource, tribal, and agricultural stakeholders recently gathered in the Coquille River Valley in Oregon to celebrate the completion of the Winter Lake restoration project that will help ensure local cattle farmers continue to thrive, while providing almost 8 miles of tidal channels and 1,700 acres of habitat for the threatened Oregon Coast coho salmon, and other fish and wildlife.

AN AERIAL IMAGE SHOWS NEW CHANNELS FOR FISH HABITAT CREATED AT WINTER LAKE, PART OF THE OREGON DEPARTMENT OF FISH AND WILDLIFE’S COQUILLE VALLEY WILDLIFE AREA. (CBI CONTRACTING VIA NMFS)

Habitat restoration and agriculture are often considered competing interests. This partnership between natural resource entities and agricultural landowners demonstrates that the two can benefit from a strategically planned project.

Lowlands in and around the Valley’s Beaver Slough Drainage District are rich pasture for cattle, and are in high demand. In the past, levees were built, channels straightened, and acres of wetlands were filled to create agricultural land.

A SIGN PUT UP FOR THE RESTORATION PROJECT DECLARES “WE GROW BEEF IN THE SUMMER AND FISH IN THE WINTER.” ACCORDING TO NMFS, THE LAND WHERE THESE CATTLE GRAZE WILL BECOME FISH HABITAT LATER IN THE YEAR. (NMFS)

But the tidal gates managing water and helping keep the land dry for grazing started failing recently and had to be replaced. The Drainage District saw this opportunity to establish a new partnership to reimagine how water is managed there.

Their vision of ‘working landscapes’ was to improve water control and protect the land from flooding during prime grazing season in the warmer months, and rebuild high-quality habitat for juvenile coho salmon in the winter.

The project’s cornerstone is a set of new state-of-the-art tide gates that can better control flooding, allowing for seasonal use by agriculture, and fish and wildlife. The tide gates, working with reconnected channels and new habitat will provide the best of both worlds.

THE PROJECT INCLUDES NEW TIDE GATES TO IMPROVE THE FLOW OF WATER. (BCI CONTRACTING VIA NMFS)

NOAA helped Beaver Slough Drainage District, the Nature Conservancy, Oregon Department of Fish and Wildlife and nearby land owner China Creek Gun Club develop plans for this comprehensive project, and supported it further with restoration and resilience grants totalling $2.7 million.

It is expected that the project could generate up to $3.4 million and 25 new jobs in the regional economy, and could then contribute an additional $3.2 million due to increased outdoor recreation spending over a twenty year period.

Along the Pacific Northwest coast wild salmon populations continue to decline. Like many northwestern rivers, the Coquille has lost much of its estuary habitat; nearly 95 percent of prime salmon spawning and rearing waters there are gone.

Habitat restoration through innovative public-private partnership projects like this are the key to success, and eventually will assist in the recovery of salmon and other fish species critical to this region’s ecosystems and communities.