A Web of Relationships
BY JEFF RENNER
The salmon made sleep impossible. The splashing from their night-time migration through the shallow water just beyond my streamside tent was almost continuous. These determined fish had not eaten in the weeks since they left the ocean. Consider running an ultra-marathon after days of fasting, and you have an inkling of the power and endurance of salmon. To witness their migration is to witness an ancient convergence of life surrendered and gifted, a cycle that reaches beyond the dawn of our own species. Forty-million-year-old salmon fossils have been found in northwestern British Columbia; their ancestors include the saber-toothed salmon, which reached lengths of nine feet and, of course, the five smaller species of contemporary Pacific salmon: chinook, coho, chum, pink, and sockeye.
Straining to track a pair of salmon upstream in the darkness, I knew persistent splashing likely marked a female excavating a depression in the gravel streambed, creating a nest for her eggs that would soon be fertilized by a nearby male. The female then moves upstream, sweeping up gravel that will drift with the current to cover and protect the embryos. She dies soon afterward.
Perhaps 20 percent of the embryos will survive to become alevins. Unable to swim, they dwell within the gravel, subsisting on the lunch bag of nutrients within their yolk sacs. Emerging from the riverbed as fry, the developing salmon begin feeding on aquatic insects. As they grow to roughly the length of your hand and develop the ability to survive in salt water, the smolt enter the vastness of the Pacific Ocean, their body weight multiplying as they feed incessantly. The imperative of their biological clock eventually drives them to return to the river or stream of their birth, intent on producing a new generation. The timing, typically one to four years, depends upon their exact species.
The salmon who survive this journey are champions of endurance. Fisheries scientists estimate that for every 3,000 eggs laid, there are two adults who return to spawn. Human activity has become a threat multiplier, further diminishing their odds of survival. University of Washington scientist David Montgomery grouped these threats into what he termed the Four H’s in his book King of Fish (Basic Books): harvest, hydropower, hatcheries, and habitat.
The challenges confronting salmon in their struggle to survive as a species along the Pacific Coast have increased more
in the last two centuries than in the preceding two million years. The magnitude and impact of the human-driven environmental damage is so great that it’s been referred to as geotrauma. A recently discovered form of rock called plastiglomerate has been held up as evidence of that trauma. A blend of plastic, sand, shells, wood, and seaweed, future geologists may use it as a fossil marker of human-driven environmental degradation.
The changes to the biosphere—the zone where life exists on Earth—are what make the determined grasp of salmon to life increasingly tenuous. These include changes in the temperature, chemistry, and movement of air and water.
One quarter of a million Columbia and Snake River salmon died before spawning in 2015. That was half of the expected migration. Water temperatures exceeded 70 degrees, increasing their susceptibility to infection and parasites and decreasing needed oxygen. In 2021, the Columbia River temperatures were even warmer. Underwater video revealed widespread fungal infections and lesions; huge clusters of salmon crowded into pockets of cooler water, desperate for oxygen; and salmon carcasses obscured warmer riverbeds nearby.
SPRING 2023 • NO. 137 8
This map, from a study by Feist et al. predicts the mortality of salmon in the Seattle area due to land use and urban development. 1
1 From: Blake E. Feist et al., “Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams,” PLoS ONE, 6(8): doi:10.1371/ journal.pone.0023424.
The Northwest Energy and Salmon Plan
The Northwest Energy and Salmon Plan, proposed by Representative Mike Simpson, is a comprehensive proposal that aims to restore and protect the migratory routes of salmon in the Columbia River Basin while also addressing the energy needs of the region and better honoring the treaties that have been established with Indigenous communities. The plan is considered one of the most significant conservation efforts in the history of the Pacific Northwest and has been welcomed by Indigenous communities in the region.
The Northwest Energy and Salmon Plan acknowledges the importance of salmon to Indigenous communities and proposes measures to restore the habitat of salmon while recognizing tribal sovereignty. Furthermore, the plan proposes to invest in renewable energy projects—such as wind and solar power—as a substitute for hydropower generated from dams that have negatively impacted salmon runs. The proposed changes to the Columbia River Basin will result in a significant reduction in greenhouse gas emissions, restore the health of the river, and create new economic opportunities for the region.
Key parts of the bill include:
• Restoring a free-flowing Lower Snake River in southeast Washington through the removal of four federal dams
• Improving water quality in the Columbia Basin, Puget Sound, and Washington and Oregon coasts
• Restoring salmon in currently blocked areas in the upper Columbia and upper Snake Rivers
• Funding the Yakima Basin Integrated Plan to protect farming communities that rely on irrigation water diverted by the dams
• Providing additional incentives to remove select fish-blocking dams in the Columbia River Basin
• Increasing tourism and recreation opportunities.
This plan can only be enacted through an act of Congress.
Take action on this bill by writing to your senators and representatives today: https://tinyurl.com/28snrmbk.
These and other die offs confirmed a 2010 University of Washington Climate Impacts Group prediction that the favorable water temperatures long enjoyed by salmon in regional waters will shrink to small, isolated patches by the end of this century.2 Such localized variation in survivability is already evident in stretches slowed by dams, which experience significantly warmer temperatures, lower oxygen levels, and toxic algae blooms. Such blooms, the result of warm water and agricultural runoff, have forced occasional summer closures of stretches of the Columbia River. Less easily detected changes in water chemistry are also killing salmon. In 2020, University of Washington scientists discovered the cause of mysterious die offs of Pacific Northwest coho salmon migrating through urban streams.3 As many as 90 percent of these salmon died before reaching their spawning grounds, because particles from vehicle tires rubbed off during travel on nearby roads and parking lots and washed into streams by rain-driven runoff. Meanwhile, the fossil fuels used by vehicles, industry, and other human activity has driven increased carbon dioxide into the atmosphere and ocean. The increased carbon dioxide levels have resulted in a process known as ocean acidification, which is threatening the insects and crustaceans salmon utilize for food.
2 N.J. Mantua, I. Tohver, and A.F. Hamlet, “Climate Change Impacts on Streamflow Extremes and Summertime Stream Temperature and Their Possible Consequences for Freshwater Salmon Habitat in Washington State,” Climatic Change 102, no 1-2 (2010): 187-223, https://doi.org/10.1007/s10584-010-9845-2.
3 Zhenyu Tian et al., “A Ubiquitous Tire Rubber-Derived Chemical Induces Acute Mortality in Coho Salmon,” Science 371, no. 6525 (2020): 185-189, DOI: 10.1126/science.abd69.
Some argue that the diminishing runs of wild salmon are an unavoidable consequence of evolution, but then so too are the shared threats to human health and survival. Research confirms the need to recognize we essentially all are Salmon People; the conditions needed for salmon to survive are also the conditions we require. Evidence of this connection includes the discovery of particular forms of nitrogen known to originate in the ocean. These isotopes of marine nitrogen, carried up rivers and streams in the bodies of salmon, have been found in the bears and birds that feed on them, in the soil that absorbs nutrients from the decaying carcasses, and in the vegetation that grows in that soil; in all life dependent upon this web of relationships. Each form of life stands as proof of the matrix of vulnerability between the elements of these ecosystems, including us.
I’m reminded of the words of University of Washington scientist David Montgomery:
“The fall of salmon populations is part of a global crisis as well, for how it unfolds may foretell the environmental future of many other regions and ecosystems. What does it say for the long-term prospects of endangered species worldwide if one of the most prosperous regions of the richest country on Earth cannot accommodate its own iconic species.”
Jeff Renner served as chief meteorologist at the Seattle NBC affiliate KING TV for over 30 years, where he also coproduced, wrote, and hosted a series of award-winning science and environmental documentaries. He remains active as an environmental activist and journalist with a particular interest in the convergence of science and faith.
9 A MATTER OF SPIRIT
“ Research confirms the need to recognize we essentially all are Salmon People; the conditions needed for salmon to survive are also the conditions we require.”
