Klamath Estuary

• Category: Marine and Oceanic Biomes.
• Geographic Location: North America.

Summary: The Klamath Estuary is located within the Redwood National Park and the Yurok Reservation in northern California and is an important habitat area for Indigenous peoples, salmon, and other wildlife.

The Klamath Estuary connects the Klamath River with the Pacific Ocean in northern California. The area at the mouth of the estuary is shared by the Yurok Indian Reservation and Redwood National Park. The estuary and river are important for fish migration; this was once the third-most-productive salmon river on the Pacific Coast, as more than one million salmon returned here to spawn each year. The estuary is home to coho salmon, a federally protected species.

The estuary area has been home to the Yurok Tribe of for 7,000 years. The Yurok depend on the estuary fishery for sustenance, and on culturally important plants including some of the willows (Salix spp.) and ferns (Pteridophyta), which are essential for basket-making and regalia. Many plants here also are important for their medicinal qualities and are used for healing and in Yurok ceremonies.

The Klamath Estuary biome provides habitat support for a great many animal and plant species, as well as opportunities for hunting, fishing, hiking, and bird watching. It plays important overall ecological roles as well; the wetlands here control floods by hydrologic absorption and storage of large volumes of water. They collect sediment, adding to vital bank and bottomland structure, while filtering water so that channels within the estuary are clear for species requiring low-turbidity conditions, and water is clean for the many species that live in it.

Fauna

The estuary is an important habitat to resident and migratory birds, particularly waterfowl. This is a vital part of the Pacific flyway between the Klamath and Siskiyou mountains. The endangered willow flycatcher (Empidonax traillii) is one species that makes its summer home in these wetlands. The great blue heron and mallard ducks are common to the area, and the Yurok use their feathers in ceremonies.

The Klamath River has a higher diversity of anadromous fish—which are born in the river, migrate to the sea, where they live, and then return to their birthplace to lay their eggs—than any other in California. The population of such fish has declined over the years, and the ongoing restoration programs require strong partnerships between the government and local people, all dedicated to preserving their numbers. Coho (Oncorhynchus kisutch), chum (Oncorhynchus keta), and chinook salmon (Oncorhynchus tshawytscha), as well as steelhead species, are key anadromous fish found here.

Chinook salmon, the largest species of Pacific salmon, is often referred to as king salmon because it can grow to 100 pounds (45 kilograms) or more, and 22–56 inches (56–142 centimeters) long. Chum salmon—from the chinook word tzum, which means spotted—are the second-most-abundant salmon species of all the Pacific varieties, and are sometimes called dog salmon.

Salmon populations are at risk when any part of their life cycle is disrupted. All species require adequate spawning habitats, such as a clean river location that is cool and well oxygenated. Without these conditions, salmon roe (eggs) may not develop properly. The salmon species of the Klamath estuary require such food as planktonic diatoms, copepods, kelps, seaweeds, jellyfish, and starfish that are found in these brackish waters. When young, they feed on insects, amphipods, and other crustaceans. They typically feed on other fish when older.

There has been great controversy over water use in the Klamath Basin. Dams damaged the salmon migration, and much of the water from the upper basin has been diverted for irrigation. Industrial pollution, mining, roads, and logging also have contributed to poor water quality. Most of the river basin is sparsely populated and rural. This may make it easier for restoration of the salmon populations, compared to rivers in more urban areas.

Flora

Vegetation of the Klamath Estuary biome occurs in five layers: aquatic, short, medium, tall, and extra tall vegetation. The aquatic layer includes macrophytes such as ditchgrass (Ruppia cirrhosa), water buttercup (Ranunculus aquatilis), and leafy pondweed (Potamogeton foliosus), which create floating or buoyant canopies at or near the water surface. This layer also includes non-rooted aquatic plants such as duckweed (Lemna spp.) and water hyacinth (Eichhornia crassipes).

Short vegetation, plants taller than 20 inches (50 centimeters), includes small emergent vegetation and plants such as watercress (Rorippa nasturtium aquaticum), saltgrass (Distichlis spicata), jaumea (Jaumea carnosa), creeping buttercup (Ranunculus flamula), and arrowhead (Sagitaria spp.), among others.

Medium vegetation never exceeds 29 inches (75 centimeters) tall; this includes pickleweed (Salicornia virginica), saltbrush (Atriplex spp.), rushes (Juncus spp.), and curly dock (Rumex crispus).

Tall vegetation, plants up to 59 inches (1.5 meters) high, includes emergent vegetation and larger shrubs such as broad-leaved cattail (Typha latifolia), bulrush (Scirpus californicus), California blackberry (Rubus ursinus), and coyote brush (Baccharis piluaris).

Very tall vegetation includes plants such as shrubs, vines, and trees that are taller than 59 inches (1.5 meters) high. These include trees like western sycamore (Plantanus racemosa), Fremont cottonwood (Populus fremontii), red alder (Alnus rubra), blue elderberry (Sambucus mexicanus), and hazelnut (Corylus californicus).

In addition to the native plants, the Klamath estuary is home to a federally endangered plant, the western lily (Lilium occidentale). This species relies on bogs, freshwater marshes, and similarly moist habitats.

Because of habitat degradation and disturbances from development, the region’s wetlands can be invaded by aggressive, highly salt-tolerant, nonnative vegetation, such as reed canary grass (Philaris Urundinacea), purple loosestrife (Lythrum salicaria), water hyacinth (Eichornia crassipes), and salvinia (Salvinia molesta). The most prevalent invasive species in the area, across several of the height layers, are reed canary grass (Philaris urundinacea), Himalayan blackberry (Rubus procerns), common reed (Phragmites australis), and the yellow pond lily (Nuphar lutea).

Environmental Restoration

In 2010, restoration and recovery projects began in the Klamath River basin. In the estuary, efforts were initiated to improve in-stream and streamside river habitats to benefit threatened coho salmon, as well as chinook salmon and steelhead trout. These included tree planting and expansion of a local plant nursery by the Yurok Tribe that was started in 2009 with funding supplied by the American Recovery and Reinvestment Act.

The tribe also installed complex in-stream structures and stabilized more than 1,000 feet (304 meters) of eroding stream bank. Ponds were built off these streams to provide winter habitat for the threatened coho salmon. Preliminary results show that 250 juvenile coho and 1,500 young chinook salmon were using this new habitat within the first year. However, drought in the 2020s has caused the main irrigation canal of the Klamath Reclamation Project to dry up. Thousands of juvenile salmon have died as a result.

The Klamath Basin Restoration Agreement also started in 2010; it included a plan to remove four dams. Scientific studies and reports were conducted to determine the impact of dam removal as a way to increase the chances of fish survival as they migrate upstream to spawn. Entities involved agreed to the resulting plan in April 2022, and in June, the Federal Energy Regulatory Commission approved transfer of the operating licenses for the dams to the nonprofit Klamath River Renewal Corporation and the states of California and Oregon as co-licensees. In September 2024, crews completed the project to remove the four dams. It was noted as the largest dam removal project in United States history. The project was not without its ordeals, however. In March 2024, hundreds of thousands of juvenile salmon died after being deposited into the Klamath River. The salmon were deposited near one of the dams and were believed to have died from gas bubble disease caused by the environment created by the dam. Environmentalists hoped that the removal of the dams would alleviate previous obstacles to salmon spawning and safe migration.

Climate Change

A report by the National Research Council suggested that the sea level offshore in this region would rise by 4 inches (10 centimeters) by 2030, and as much as 2 feet (61 centimeters) higher by 2100, which could cause wetlands within the Klamath Estuary biome to disappear. The plants in these areas require more sediment to keep up with the rise in sea level. The deposition of sand and sediment is unlikely to change, however. Therefore, eventually these wetlands could be underwater.

The wetlands also could migrate inland if there is sufficient room. Removing upstream dams has been viewed as a way to increase sediment flow into the estuary and potentially offset sea-level rise in part. Further, sea-level rise in northern California is lessened slightly by upthrust in the land through plate tectonics and the ongoing uplift along the San Andreas Fault.

Climate change already is affecting the fragile estuary; scientists continued to prepare weather and climate models to help officials at all levels forecast and deal with the oncoming changes. Three such models agreed that future summers would be drier than historical records, with precipitation declining 11–24 percent. Vegetation was considered likely to shift to favor grasslands such as sagebrush and juniper in the upper basin; oaks and madrone would be favored over maritime conifer forest of redwood, Douglas fir, and Sitka spruce, which were all projected to decline. Projections also indicated that wildfires would increase 11–22 percent by late century. Heat waves, severe precipitation, and prolonged drought were all expected to increase.

Scientists have continued working to find ways to help increase the resilience of local plant and animal communities, to blunt the negative impacts of climate change. This sense of environmental stewardship has seemed to be on the upswing in the Klamath River area.

Bibliography

Barr, Brian R., Marni E. Kooperman, Cindy Deacon Williams, Stacy J. Wynne, Roger Hamilton, and Bob Doppelt. Preparing for Climate Change in the Klamath Basin. Ashland, OR: National Center for Conservation Science & Policy and the Climate Leadership Initiative, 2010.

Flaccus, Gillian. "Farmers, Tribes in Klamath Basin Get the Grim News on This Year's Water Restrictions." Oregon Public Broadcasting, 11 Apr. 2022, www.opb.org/article/2022/04/11/farms-fish-klamath-basin-drought-water-restrictions/. Accessed 6 Nov. 2024.

Kuta, Sara. “Hundreds of Thousands of Salmon Die After Release in Northern California’s Klamath River.” Smithsonian Magazine, 8 Mar. 2024, www.smithsonianmag.com/smart-news/hundreds-of-thousands-of-salmon-die-after-release-in-northern-californias-klamath-river-180983914/. Accessed 6 Nov. 2024.

Patterson, William D. Klamath River Estuary Wetlands Restoration Prioritization Plan v1.0. Klamath, CA: Yurok Tribe Environmental Program, 2009.

Powers, Mary B. "Largest-Ever US Dam Removal Project Gets Federal Agencies' Nod." Engineering News-Record, 21 Apr. 2022, www.enr.com/articles/53978-largest-ever-us-dam-removal-project-gets-federal-agencies-nod. Accessed 6 Nov. 2024.

Ramirez, Rachel. “The Largest Dam Removal Project in the US is Completed—A Major Win for Indigenous Tribes.” CNN, 1 Sep. 2024, www.cnn.com/2024/09/01/climate/klamath-dam-salmon/index.html. Accessed 6 Nov. 2024.

Terence, Erica, et al. “Restoring the Shasta for Coho Salmon.” Klamath River News 8 (Summer 2012).