Recent research in the Salish Sea and off the Washington coast examined the orca’s seasonal diet. It is well documented that orca prefer Chinook, presumably because of their larger size, but it turns out “Chinook salmon were identified as an important prey item year-round, averaging ~50% of their diet in the fall, increasing to 70–80% in the mid-winter/early spring, and increasing to nearly 100% in the spring. Other salmon species and non-salmonid fishes, also made substantial dietary contributions.” How did the researchers establish this detailed diet analysis? Poop. More specifically, analysis of feces collected from October to May 2004-2017. The authors reach a number of conclusions, ranging from noting that most Chinook consumed consisted of 50-80% hatchery fish, and that the unexpected diversity in species consumed suggests that a successful orca recovery strategy include more than just Chinook enhancement.
Brian Foote, co-founder of EarthViews, sent us a special treat: a view of Issaquah Creek from the hatchery weir down to Confluence Park. This amazing technology gives you the ability to virtually ‘walk’ down the middle of Issaquah Creek, spinning your head for a 360 degree view — all from the comfort of your desk chair or smartphone! Check it out. We’d love to get your feedback! Should we do more of the Creek — maybe from the mouth to the headwaters? Maybe do this multiple times per year? Tell us what you want.
When one hears about farming fish, you think about the net-pen rearing of Atlantic salmon or trout — which we know pose threats to our resident and migratory salmon. Cramming thousands of salmon into a small pen creates a continuous, concentrated plume of fish excrement for the local environment. This plume pollutes the environment, and since many pens are built in inlets to reduce wave action, the effluent concentrates in these areas.
The collapse of the net pens off Cyprus Island in 2017, moreover, demonstrated how the largest net pen operators can fail to comply with existing regulations, which should cause all of us to closely reconsider this type of farming.
Thankfully, Canada is addressing these problems by phasing out pen-rearing of salmonids (including salmon and trout) and encouraging a whole new form of aquaculture: Recirculating Aquaculture Systems (RAS). RAS are land-based, closed systems which eliminate the problems and risks of net pens. The fish are raised in tanks, and the water goes through several stages of treatment before recycling back into the closed system. No effluents are released, and potential disease is contained.
Last year, Canada’s Prime Minister Justin Trudeau committed to a transition from net pens in coastal waters to RAS systems by 2025. British Columbia is carrying out this national policy locally, detailed in this excellent article in RASTech Magazine: Canada Begins Transition for Salmon Net Pen Farms. Check it out!
An agreement has been reached between California, Oregon and PacifiCorp company to remove four hydroelectric dams along California’s second largest river (it flows between the two states on its way to the sea in Northern California). The project will be the largest, most ambitious of its kind, removing four hydroelectric dams on the Klamath River, opening up hundreds of miles of river to salmon.
Negotiations have been ongoing for years between the three entities, and an agreement has finally been negotiated.
Background:
PacifiCorp (which is owned by Warren Buffet’s Berkshire Hathaway) owns the four dams:
- Iron Gate Dam
- Copco 1 Dam
- Copco 2 Dam
- J.C. Boyle Dam
The dams are strictly hydroelectric (generating a combined 163 MW of power, which is considered relatively small) and do not provide water for irrigation. The lowest dam on the river (Iron Gate Dam) provides no passage for fish, thereby locking salmon and steelhead out of hundreds of miles of upstream habitat. The river supports coho, spring Chinook, fall Chinook and steelhead.
Historically, the Klamath supported a large spring Chinook run which — despite the installation of a hatchery when the lowermost dam (Iron Gate) was built in 1964 — did not rebound. It is estimated that the Klamath supported up to one million returning salmon each year prior to the dams. Today, with the assistance of the hatchery, it averages between 100,000 to 200,000 salmon.
Causes for decline:
In addition to the blocking of fish passage, upstream management of other dams — in the cold headwaters of the Klamath — have prioritized irrigation management over salmon management, which presents a particular problem in the Klamath River. While all salmon require cool/cold river water, in the Klamath there is a lethal parasite (called Ceratonova shasta) which thrives in warmer water temperatures, and which is lethal to juvenile salmon. In 2014 and 2015, when the Bureau of Reclamation held water behind their headwater dams on the Klamath for irrigation, the parasite population exploded in the low flow. It is estimated that 80-90% of juvenile Chinook were killed in those two years by the parasite. The Klamath tribes have been fighting in court (and winning) for improved dam management for salmon.
The agreement
PacifiCorp has been operating the four lowermost dams on the Klamath for years under an expired hydroelectric license, which pre-dates modern environmental laws. The company has determined that the cost to renovate the dams with fish ladders is greater than participating in their removal.
In the original deal to remove the dams (which fell through):
PacifiCorp wanted to transfer its license and contribute $200 million to bow out of the removal project. An additional $250 million would have come from a voter-approved California water bond. But regulators would only agree to it if PacifiCorp remained a co-licensee, which PacifiCorp considered to be a non-starter.
In this new deal:
Oregon, California and PacifiCorp each pay one-third of the cost of removal. The project is on track to begin in 2022, with removal in 2023, and restoration work to follow beyond 2023.
This is a remarkable success story about people working in partnership to benefit salmon.
Sewage plants release 26 million pounds of nitrogen in Puget Sound each year, according to the Department of Ecology. This is a serious problem for salmon, orcas, and the Puget Sound food web.
If you’re a gardener, you know that nitrogen is a key component in manure, infusing our vegetable gardens with explosive harvest potential. Likewise, in water, concentrated nitrogen fuels explosive growth (blooms) of phytoplankton (algae) — particularly from spring to early fall when there is more sunshine and the temperatures are warmer. As algae blooms use up the nutrients in the surface water, their growth slows and they eventually die. Their cells sink to the ocean floor, where they are decomposed by bacteria, which consume oxygen in the water (and release CO2). Large algae bloom die-off’s can create oxygen-depleted dead zones where aquatic life cannot survive. Even when they don’t create dead zones, the CO2 released by the bacteria during decomposition mixes with H20, increasing acidity, which impacts shellfish. No matter how you look at it, these blooms are bad for aquatic ecosystems, and the 26 million pounds of nitrogen introduced into the Puget Sound from wastewater treatment plants creates a devastating problem for the food web, all the way up to salmon and orcas.
Our wastewater treatment plants fall short. The article points out that Washington state treatment plants are behind the times. Requirements for upgrades were last made in the 1980’s, where they adopted technology developed in the early 20th century. Most treatment plants in Washington today simply do not remove nitrogen.
The article posted on Crosscut.com presents more details on the current debate on how we can meet Clean Water Act standards for dissolved oxygen for the Puget Sound, but where there is no debate is that nitrogen from human activity is to blame. We encourage you to read the article to learn more about the timeline, costs and interim measures associated with upgrading our wastewater treatment plants throughout the Puget Sound.
Our coho have a perilous journey from the Chittenden Locks to the Issaquah Salmon Hatchery — and researchers at the University of Washington, Tacoma and Washington State University, Puyallup have identified the chemical responsible for mass pre-spawning deaths of adult returning coho in our urban streams.
According to the article, 1% of adult returning coho typically die before spawning. But in these mass death events, anywhere from 40% to 90% perish in the most affected streams.
The article highlights an amazing piece of research and we encourage you to read it. Investigating thousands of potentially lethal pollutants, the research team narrowed it down to just one elusive culprit: 6PPD-quinone, a fish-toxic compound generated by the breakdown of automobile tire particulate. In other words, a chemical preservative found in tire dust is broken down by ozone, creating this highly toxic 6PPD-quinone. This is a remarkable feat of scientific research and determination.
Interestingly, this study suggests that 6PPD-quinone specifically, mortally impacts coho — and not other species of salmon.
It is worth considering just how quickly this chemical affects adult returning coho as they return to their home streams.
Researchers call for the development of a “green” chemical alternative to the offending tire preservative. While we agree that better treatment and management of stormwater runoff would also be ideal and should be pursued, it is challenging to implement.
We encourage you to read the article and enjoy their embedded, instructive videos.