The Willamette & Rogue

For our final week of Orca Action Month’s “Stream to Sea” we continue down the coast to the southern range of the Southern Resident orcas.

View of Cannon Beach in Oregon with Haystack Rock in the background. ©Marisa Estivill

Willamette River:

The Willamette River in Oregon is part of the Columbia River Basin, contributing 15% of the Columbia’s average annual flow. It flows north for 187 miles and is the largest watershed in Oregon, draining 11,487 square miles. Willamette River spring Chinook are part of the Columbia Basin spring returns and therefore were historically important to Southern Resident orcas.

The Willamette Valley is home to 2/3 of Oregon’s population and it has been heavily impacted by development, urbanization, and industrialization. Pollution is a major concern with high levels of heavy metals, PCBs and pesticides, particularly in the section around Portland which was designated a Superfund site in 2000.

The river is heavily dammed, with 15 large dams and multiple smaller ones on some of the river’s tributaries. The primary function for most of these dams is hydroelectricity, while some provide important flood control and water storage. Poor fish passage at these dams, along with loss of habitat, have negatively impacted salmon. While historical abundance was close to 300,000 spring Chinook, recent averages are fewer than 5000 fish.

In 2008, Willamette Riverkeeper designated the full length of the river as the Willamette River Water Trail, which was then made official and expanded by the National Park Service in 2012.

Significant habitat restoration projects have taken place along the river, and the Willamette River Greenway System now includes over 10,000 acres along the river, most owned by Oregon State Parks.

Rogue River Canyon in southwest Oregon. Creative Commons

Rogue River Watershed, USGS, Public domain, via Wikimedia Commons

Rogue River:

The Rogue River in Southwest Oregon flows 215 miles from the Cascade Mountain Range to the Pacific Ocean and drains 5156 square miles. The river contains several salmon and steelhead runs, including spring and fall Chinook, summer and winter steelhead, and Coho. Both spring and fall Chinook salmon are included in the Southern Resident Killer Whale Priority Chinook stocks report, and spring Chinook returns overlap when the whales are primarily off the Oregon Coast in the late winter and early spring. Coho in the Rogue River are currently listed as threatened under the Endangered Species Act, and spring Chinook are “potentially at risk.”

While returns are still below desired target levels and fluctuate on an annual basis, generally the status of Spring Chinook is gradually improving.

The river has a long history of dam construction and removal, including a legendary incident involving an early fish-blocking dam that was blown up by vigilantes who were upset by the impacts to salmon. Concentrated dam removal efforts began along the river in the early 2000s, and by 2009, all but one of the main-stem dams had been removed. The one remaining is the William L. Jess Dam which is used for flood control and hydroelectric. It lies 157 miles inland and there are no salmon above that dam. Current ongoing issues in the Rogue River include pollution from stormwater and wastewater runoff, climate change and drought. Since flows in the river are generally quite low, extremes from climate change can be devastating.

The Rogue River is one of the original eight rivers included in the Wild and Scenic Rivers Act of 1968, which is meant to preserve rivers with outstanding natural, cultural, and recreational values in a free-flowing condition. In 2019, 140 additional miles of tributaries were added to the designation.

Sources/resources:

http://willamette-riverkeeper.org/basicsfacts

Where Do The Southern Resident Orcas Go When They Leave the Salish Sea?

This week, we travel out of the Salish Sea into the Pacific Ocean to explore some important habitat in the coastal waters off British Columbia and Washington.

Swiftsure Bank is an area of rich, productive water off the coast of Vancouver Island. It is located about 15 miles west of the entrance to the Strait of Juan de Fuca, where deep submarine canyons meet the continental shelf. As currents rise from the canyons they bring cold nutrient-rich waters to the shallow bank. This upwelling becomes the basis for plankton which in turn supports a diverse ecosystem that includes many species of fish. Many salmon migrate through Swiftsure Bank on their way to the Salish Sea, making it an important foraging area for resident orcas, and acoustic data has shown that Southern Residents are present there in all months of the year.

In 2018, Canada added Swiftsure Bank to Southern Resident orca critical habitat, which is defined as "the habitat that is necessary for the survival or recovery of a listed wildlife species.” In recent years, J, K, and L Pods have been spending more time at Swiftsure Bank during the summer months, and fewer days in their core summer habitat around the San Juan and Gulf Islands as Fraser River Chinook has continued to decline. Many people believe that these inland waters are important to the Southern Residents not just as a traditional source of prey, but for cultural reasons as well, and that their decreased presence here may have long term effects on their social structure and culture. While their absence is keenly felt, the fact that they are foraging at Swiftsure Bank during the summer, and seemingly finding abundant food is a comfort. Hopefully this prey source will continue to sustain them until we can restore the Salish Sea salmon runs to a level that will allow Southern Residents to thrive here once again.

Further south, off the coast of Washington several rivers and streams flow from the Olympic mountains to the Pacific Coast. Salmon runs in these rivers are currently relatively stable and while a number of spring Chinook runs on the west coast are in decline, they still have a good chance of recovery with robust restoration efforts. In a 2018 report by NOAA Fisheries and Washington Department of Fish and Wildlife, the Washington Coast stock was listed a priority Chinook stock for Southern Resident orcas. This stock includes Chinook salmon from the Hoh, Queets, Quillayute, and Chehalis Rivers, as well as additional small rivers that flow into Grays Harbor.

To determine priority stocks, the report looked at three evaluation factors, including: observed part of Southern Resident diet; salmon consumed during reduced body condition or diversified diet; and spatio-temporal overlap between Chinook salmon and Southern Residents. The purpose of the report was to ”identify Chinook salmon stocks that are important to Southern Resident killer whales (SRKW) to assist in prioritizing actions to increase critical prey for the whales.” Combined with additional research, this report could be an effective tool to determine where restoration and protection efforts might be most beneficial at increasing prey for the Southern Resident orcas.

Sources:

Riera, 2012. Patterns of seasonal occurrence of sympatric killer whale lineages in waters off Southern Vancouver Island and Washington State, as determined by passive acoustic monitoring

www.nps.gov.

Southern Resident Killer Whale Priority Chinook Stocks Report 2018.

Exploring the History of Salmon in the Columbia and Snake River Systems

This week, we continue further down the coast to explore the Columbia-Snake Rivers and their connection to northwest salmon and Southern Resident orcas.

Historical salmon data for The Columbia and Snake Rivers estimates that 10-16 million wild salmon and steelhead entered the Columbia River Basin to spawn, annually, with 2-4 million more utilizing the Snake River watershed. The Columbia River Basin was once home to the largest runs of Chinook salmon in the world, and roughly half of those Chinook returned to the Snake River in the spring and fall seasons about 200 years ago. Today, less than 1 million fish return to the Columbia River, and fewer than 60,000 wild fish return to the Snake each year.

What began the downfall of salmon populations in this river system?

Largely, the establishment of salmon canneries in 1867 was the first cause of decline in wild salmon populations. In 1879 it was reported that over half a million salmon, with an average weight of 22 pounds, were caught and canned in a single season. At the turn of the century, widespread concern for catch rates of salmon caused the people of Oregon to pass two laws limiting fishing on the Columbia and other rivers. While efforts to curb overfishing (by also banning seine netting) continued into the late 1940s, major modifications to the Columbia and Snake Rivers were also in progress in the form of dams and hydrosystem facilities to generate power, provide flood control, and irrigation options for farming.

Hydrosystem Complexities for salmon on the Columbia-Snake River: Dams and Salmon Don’t Mix

Dams built in the 1930s and 1950s along the Columbia River, and dams built in the 1960s and 1970s along the Lower Snake River, have impeded salmon from reaching their northernmost and easternmost spawning sites, since. By 1986, Snake River Coho were extinct. Today, all surviving Snake River salmon populations are listed under the Endangered Species Act and threatened with extinction. Per the Endangered Species Coalition, “On average, there is a major dam every 72 miles in the Columbia River Basin. The upper stretches of the Columbia and the Snake rivers are impassible at the Chief Joseph and Hells Canyon dams, respectively. But salmon can navigate past some other dams.

Four federal dams managed by the Army Corps of Engineers on the lower Snake are built with fish ladders for returning adult salmon, but out-migrating juveniles (smolts) have a very difficult time getting to the ocean.”

The nine dams along the Columbia prior to reaching Chief Joseph dam, and eight dams along the Columbia-Snake prior to Hells Canyon present massive challenges to both inbound and outbound salmon. Out-migrating salmon smolts have a perilous journey, as they must navigate through a series of hydrosystems, dam turbines, sluiceways, stagnant reservoirs, warming waters, contaminants, and various predators before reaching the Pacific Ocean.

Even if a juvenile salmon manages to reach the Pacific Ocean against these odds, there may still be ramifications leading to mortality due to the stress of navigating these hydrosystems.

While complex in nature due to a degree of variables, fish Biologists and scientists that have studied Columbia-Snake River smolts have discovered that the hydrosystem stressors experienced by out-migrating juveniles may also likely cause some salmon a delayed mortality. Hydrosystem stress on salmon leads them to delay their development and suppress their immune systems, as more energy is channeled into survival, instead. Entering the ocean in a weakened condition can increase the chance that these salmon will be susceptible to disease, parasites, or may not successfully adapt to the saltwater environment. Even if they make it downstream through each aspect of the hydrosystem, they still may not become a viable specimen in their ocean environment. Which also means they will not become accessible orca food.

Actions To Bring Wild Salmon Back to the Columbia-Snake River System:

According to Wild Orca, “NOAA Fisheries, the federal agency charged with protecting both endangered orcas and endangered salmon, has described the decline of Columbia Basin chinook salmon as, “[p]erhaps the single greatest change in food availability for resident killer whales since the late 1800s...”

Whale and Dolphin Conservation adds, “Breaching the Snake River dams, in combination with increased spill (water flow) through other dams in the Columbia River Basin, provides more certainty of long-term survival and recovery for wild Snake River Chinook salmon than any other measure… Removing the dams and increasing spill would help the river system return to more natural conditions, which can help increase survival of wild Snake River Chinook salmon to the point of rebuilding healthy populations – something that the federal agencies themselves recognized in their recent review of dam operations.”

To read more details about the 2020 Federal EIS Report, follow this link: For first time in 20 years, feds take deep look at hydroelectric dam removal on Lower Snake River | The Seattle Times

Resources: https://us.whales.org/deep-dive-snake-river-dams/ | https://www.endangered.org/orca-salmon-and-rivers/ | https://www.columbiariverkeeper.org/columbia/salmon-and-steelhead#:~:text=The%20Columbia%20River%20Basin%20once%20produced%20more%20salmon,number%20declined%20to%20less%20than%201%20million%20fish. | https://www.idahorivers.org/lsrd | https://today.oregonstate.edu/archives/2008/oct/new-study-salmon-smolt-survival-similar-columbia-and-fraser-rivers | https://www.wildsalmon.org/images/factsheets-and-reports/2015-SOS-FS-CB-salmon-status.pdf