Thursday, December 21, 2017

NO PANACEA


On it’s face, that’s hardly notable.  Last August, a complex of deteriorating metal fish pens failed, releasing at least 160,000 invasive Atlantic salmon into Puget Sound.  From there, some salmon ascended coastal rivers, and have been found as much as 50 miles upstream, not far from the spawning grounds of already badly stressed native Pacific salmon species.

The natural resources director of the Upper Skagit Indian Tribe, which has a deep cultural association with the native salmon, has reportedly caught more Atlantic salmon than natives when sampling the river to determine the size of this year’s chum salmon run.

That has a lot of people in the region upset.


“They’re kicking, they’re swimming fine, they’re still decent-looking fish.  I guess it’s not a stretch to say that they can’t go that extra 10 miles to get to the major spawning grounds.
“Is there some sort of stress that’s put on the native fish in the spawning grounds by having these other fish present?  We just don’t know.”
Jim Walsh (R-Aberdeen), sponsor of one of the bills that would outlaw the farming of non-native fish, said

“Our native stocks are like a person whose immune system is already compromised.  And the introduction of the non-native species into our native waters is like a cold. 
“Where to a healthy person the cold would just be a nuisance, to a person with a compromised immune system a cold can be fatal.”
Given such fears, taking a precautionary stance against farming foreign species makes sense.
However, not everyone sees such aquaculture projects as a threat; some see opportunity, perhaps none so much as the current United States Secretary of Commerce, Wilbur Ross, who said at his confirmation hearing that

“Given the enormity of our coastlines, given the enormity of our freshwater, I would like to try to figure out how we can become much more self-sufficient in fishing and perhaps even a net exporter.”



“develop techniques and business models to grow domestic seafood production.  A priority is to consider promising but less commercially developed technologies for finfish, shellfish, seaweed, and other relative newcomers to the domestic aquaculture industry.”
There is no requirement that the farmed species be native to the region, although

“Proposals that focus on projects that relate to enhancing the mission of [ASMFC] to rebuild fish stocks and protect essential habitats will be given priority.”
NOAA Fisheries is apparently funding such projects

“to offset a $14 billion seafood trade deficit in the U.S.”
But how to efficiently aquaculture species, both traditional and new, isn’t the most important question.  That is whether the economic benefits of the proposed aquaculture projects are sufficient to justify the possible economic, environmental and social costs.

The answer to that is not clear.

Some aquaculture projects can certainly be beneficial.  Traditional clam, mussel and oyster beds, that are seeded and harvested by their owners, and allow the public access to the waters, but not the shellfish-strewn bottom, can add needed filter feeders to once-pristine bays and estuaries, that have become murky with phytoplankton due to nitrogen and phosphorus runoff from septic tanks, fertilized lawns and the like.

Similarly, “vertical farms” of shellfish, kelp and the like can provide filter feeders and, in the case of kelp, directly remove excess nutrients from the water, but do so at the cost of public access to sections of once-public waters.  Without a robust ocean planning process, the chance for user conflicts is high.

Once you move from kelp and shellfish into fish farms and the like, the question becomes a lot more complicated.

Fish are animals, and have the same basic needs and problems that face animals generally.  They must eat, defecate and excrete.  They can contract various diseases and parasites.  And they can escape into ecosystems where they do not belong.

Those things make estuarine, coastal and ocean aquaculture problematic, because the ocean is an open system; the farmed fish may be contained in pens, but their excess food, their bodily waste and their parasites can and do flow with the current that passes through such pens, and on into the greater marine environment.

This year’s collapse of fish pens in Washington’s Puget Sound, and the escape of many thousands of Atlantic salmon into the watershed is, unfortunately, not unique.  Pink salmon, a species native to the West Coast of North America, have been caught by anglers in 236 Norwegian rivers, after escaping from Russian fish farms and establishing a self-sustaining population in the White Sea.  Biologists fear that such invasive salmon may create spawning competition, hybridizing with native sea (brown) trout; compete for food with native salmonid species; introduce diseases into the Atlantic salmon population, while serving as a vector that transmits local diseases from the White Sea to other waters; block native salmonids from their spawning grounds; and act aggressively toward native salmonid juveniles.

Stray pink salmon from Norway and Russia are now appearing in Scots and Irish rivers, as well, although biologists hope that the waters there will be too warm to allow the invasives to gain a foothold.

In Louisiana, Asian tiger shrimp, believe to be escapees from aquaculture operations in the Dominican Republic, have also established a self-sustaining population.  The big crustaceans, which can reach lengths of over a foot and weights of over a pound, breed faster than the native shrimp and happily feed on shrimp smaller than themselves, making them a real threat to native shrimp populations.  And Louisiana isn’t the only place they’ve turned up; tiger shrimp have been caught all along the coast, from North Carolina to Texas.

The threats posed by such farmed non-native species, has caused some environmentalists to ask whether the farmed animals themselves constitute a form of pollution.  At least one court has found that they do.  However, whether or not that finding ultimately becomes settled law, there’s no question that the open-water fish farming results in a lot of pollution going into the water.


“We’ve come to the point where we view these farms as hog lots or feedlots of the ocean.  They breed disease and parasites.  Like other big animal feedlots there are lots of problems.  Some of their practices are beginning to improve, but over all the impact is not lessening.”
And that’s not only the opinion of a conservation director at a conservation organization like TU.

“Salmon farming can have a variety of effects on the marine environment, through the discharge of nutrients, solid waste, medicines and antifoulants…
“The process of fish farming releases nutrients such as nitrogen and phosphorus, from fish feed into the marine environment in a soluble form.  These nutrients can enhance the growth of marine plants and algae…
“Waste feed and faeces from fish farms can collect on the seabed under fish cages.  This increase in organic matter has an impact on the benthic environment, affecting the nature and chemistry of sediments, and can reduce the diversity of animals living there.
“…Farmed salmon are susceptible to infestations of parasitic sea lice that cause considerable stress to fish and economic losses to the industry.  Sea lice on farmed fish could potentially be transferred to wild salmon and sea trout…The fish farming industry control sea lice using chemicals that can be toxic to marine invertebrates…
And even efforts to develop a “clean” solution to parasite problems can have unexpected adverse consequences.  

In the United Kingdom, Scots fish farmers have removed a large number of wrasse—a small fish that feeds on a variety of crustaceans, including sea lice—from their native habitats off England and Scotland and introduced them into salmon pens, to control the sea lice infestations.  Both anglers—who enjoy catching, but usually release the wrasse—and conservation advocates are concerned that such large-scale removals could upset the balance in local ecosystems; the salmon farmers deny that a problem exists, despite the fact that wrasse populations off Norway, where salmon farms abound, are shrinking.

Thus, there is a tension between the need for the products produced by fish farms and the harm that such farms can cause to native ecosystems.  The solution for that conundrum may be found in a very unexpected place:  On dry land.


“Raising Atlantic salmon on the West Coast has always struck me as unbelievably stupid.  The lessons of introduced species were there way before Atlantic salmon were moved [into that ecosystem].”
But he makes an exception for salmon raised on land—the only place that he believes such salmon farms belong.

In fact, once people make the conceptual leap to raising fish on land instead of in open-water pens, entirely new opportunities open up. 

First and foremost, the fish can’t escape and create environmental problems.  They’re grown in tanks, not in open-water enclosures, so if they escape their confinement, they’re stuck on dry land.  But that’s not the only advantage. 

The water from Desert Springs’ wells is somewhat salty—salty enough to kill most farm crops, but also salty enough to cause farmed fish to thrive even better than they would in pure fresh water.  And in an ocean or estuary environment, the fish’s waste products would become pollutants, excess nutrients that could lead to unwanted plankton blooms and other adverse effects.   In the piped-in water from the wells, the same waste becomes fertilizer, nitrogen and phosphorus compounds that allow Desert Springs to grow acres of wheat, sorghum, alfalfa and barley without the need to purchase any commercial fertilizer at all.

So it appears it’s possible to have fish farms, and good conservation outcomes, too.

But NOAA Fisheries’ current plan to hand out $450,000 grants for pilot projects along the East Coast is not the way to get that done. 


Better that such $450,000 be earmarked for stock assessments and better fisheries science, while farmers like those at Desert Springs—innovative entrepreneurs who have learned how to grow fish and plant crops in new and creative ways that work together—run their aquaculture operations hundreds of miles from the coast, where they can do no harm to natural populations, and produce only good products.

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