Wild-salmon advocates and supporters of fish farms are going online to debate a recent report on the impact of sea lice on young salmon.
On its website, the Raincoast Conservation Foundation reacted to criticism of the report that had been posted by local fish farmers and by a Norwegian-based site. Some excerpts from the response:
Raincoast biologist Michael Price is lead author on the recently released peer-reviewed paper Evidence of farm-induced parasite infestations on wild juvenile salmon in multiple regions of coastal British Columbia, Canada. Co-authored by Alexandra Morton and John Reynolds, and published in the Canadian Journal of Fisheries and Aquatic Sciences, the paper suggests that salmon farms in multiple regions elevate levels of sea lice on wild juvenile salmon. Below, Michael addresses some of the criticism leveled against the paper from the fish farm industry.
Positive Aquaculture Awareness – November 9, 2010. Criticism: “What we have here is a deliberate failure to communicate. When you look closely, the authors make their data say all sorts of things that it doesn’t really support. And at the end of the day, they are repeating the same tired old unproven mantra (“there are lots of sea lice on fish around salmon farms, therefore they are coming from salmon farms, therefore we must put all salmon farms on land”). Any Logic 101 student could point out the flaws in that argument. Correlation does not equal causation.”
Response: Because independent scientists in British Columbia do not have access to salmon farms or farm data, and are thus restricted to field-based correlative analyses to test the effect of salmon farms on sea lice infestations, evidence becomes compelling only after extensive replication. Associations between wild juvenile salmon and farm-induced sea louse infestations have been repeatedly documented in the Broughton Archipelago (Morton et al. 2005; Krkosek et al. 2005a, 2006) and the Georgia Strait (Morton et al. 2008).
BC Salmon Farmers Association – November 10, 2010. Criticism: “The trouble is that their overly-simplistic analysis has significant gaps, reuses questionable methodology and is based on flawed assumptions. For example, the ‘control site’ – the area with no farms where they collect samples to compare with fish from near farms – has significantly lower salinity levels than the other locations. Since sea lice levels are naturally lower where salinity is reduced, this makes it a poor comparison.”
Response: Salinity readings were lower on average in Bella Bella where there are no farms, but were within the tolerable range for both sea louse species. It is true that this may have accounted for the exceptionally low lice levels on juveniles in the Bella Bella region. However, we also compared lice levels within each salmon farm region between sites of Low Exposure to farms and High Exposure to farms. Juvenile salmon assessed at High Exposure sites consistently hosted significantly higher lice levels than juveniles at Low Exposure sites in all 3 salmon farms regions, even though salinity values were similar at all sites. This suggests that salmon farms are a contributing factor to louse infection levels. ...
Fish Farming Xpert – November 11, 2010. Criticism: “The number of sea lice in the natural environment is affected by the salinity of the ocean. There is a genetic difference between sea lice in the Pacific Ocean and the Atlantic Ocean. Wild salmon in BC have a natural ability to shed sea lice once the fish have reached a certain size. These are all important points proven in the expansive body of sea lice research that need to be considered when reviewing the latest paper from anti-salmon farm campaigner Alexandra Morton, Michael Price and John Reynolds.”
Response: Salinity is one factor among many that may influence the number of sea lice in coastal areas; temperature of the ocean is another. However, a more influential factor is the presence and abundance of host fish for lice to successfully reproduce and complete their life cycle. Salmon farms host millions of domesticated hosts in crowded conditions for long periods of time – a classic scenario for pathogen proliferation, and sea lice are one such pathogen that proliferates on salmon farms. ...
Crawford Kilian is a contributing editor of The Tyee.
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doggone
1 year ago
Meantime, back at the (fish) ranch
Lest this discussion becomes entirely dominated by numbers and details such as: How many sea lice can stick to a salmon smolt at this or that salinity? I would like to point out the difference in tone of the above "call and Response".
The Crits make claims such as:
What we have here is a deliberate failure to communicate. When you look closely, the authors make their data say all sorts of things that it doesn’t really support
and:
The trouble is that their overly-simplistic analysis has significant gaps, reuses questionable methodology and is based on flawed assumptions.
Seems to me those things could be said about open net fish farming supporters.
On the other hand defender of the report seem to actually read the criticism and respond directly
SharingIsGood
1 year ago
29% owner - BC's Marine Harvest admits fault
"John Fredriksen, a Norwegian shipping and oil industry billionaire who owns a 29 per cent share of Marine Harvest, surprised anglers and conservationists by directly linking fish farms to plunging wild fish populations – a link the industry has repeatedly disputed. A keen angler who is reputedly worth £3.5bn and has a home in Chelsea, he told a Norwegian newspaper earlier this year: 'I am concerned about the future for wild salmon. Fish farming should not be allowed in fjords with salmon rivers.'"
http://www.guardian.co.uk/environment/2007/sep/29/fishfarm
Note that Norwegian-based Marine Harvest produces about 1/3 of the world's farmed fish and is the largest aquaculture company in BC.
http://www.marineharvestcanada.com/
Illahie
1 year ago
The basic problem is that
Crawford seems incapable of practicing balanced journalism.
He could note for instance that farmed fish tend to be devoid of lice during the smolt out migration. If they have no lice how could they pass an infection along?
He could note that salinity levels tend to be so low during the smolt out migration, the salinity levels are in fact are especially lethal to juvenile sea lice (they fill up with water until they die) and even deadly to adult sea lice.
He could ask Morton how she knows that there is a yet unidentified virus out there.
Is Crawford really that gullible, or is the cause more important than the truth?
I think that there are a few in the environmental movement that make the actions of big corporations seem like saints.
SharingIsGood
1 year ago
What's to argue?
The largest shareholder of the largest fish farm company in the world has said that fish farms are responsible for the decline of wild salmon. If he is claiming responsibility, then the only responsible thing to do is follow what he suggests. Get fish farms out of the wild salmon's path.
Illahie
1 year ago
SharingIsGood, you have the wrong ocean
There are real issues with regards to wild stocks in the Atlantic. The Atlantic Salmon evolved about 20 million years ago, and has not changed much since. There are real issues with survival, and Fish Farms are part of the problem in the Atlantic.
Kilian however is writing about Fish Farms in the Pacific Ocean. The issues here are quite different. We do not have the serious issues that they have in the Atlantic.
Here we have issues such as over fishing and Urban Sprawl paving over some of the Fraser Rivers finest Coho habitat.
SharingIsGood
1 year ago
As far as I'm concerned...
It's one big ocean. Atlantic or Pacific, whenever salmon fish farms have been placed in the path of wild salmon, the numbers of salmon decline - notwithstanding one aberrant year of a large sockeye run on the Fraser due to luck.
"An average farm of 200,000 salmon produces the daily equivalent amount of feces as a town of 62,000 people. This waste accumulates on the sea floor below the farm pens and generates killer bacteria that consume the oxygen vital to wild bottom fish (3)."
http://www.circleofresponsibility.com/page/297/fish-farming.htm
Now in human terms, supose you had a toddler that had in its head a beacon to know the direction he must travel to get to his home. NOw you send that toddler out on his own through the plague-filled ghettos and open untreated sewers (fish farms) to make his way home.
Talapia, catfish, arctic char, perch and trout can be grown commercially at a profit in on-land containers - often employing aquaponics. Talapia and catfish can live and grow on vegetable matter - a win-win. I think we just need to learn how to eat more talapia and catfish while we let the oceans heal as best they can from the destructive farming, mining, fishing, transportation and construction practises we have employed over the last 100 years. We need to stop being so selfish with the resoources of the planet.
Here's a link, or google aquaponics yourself:
http://www.socialearth.org/aquaponics-the-answer-to-sustainable-farming
Illahie
1 year ago
SharingIsGood is bad I think
Just how big is the Fish Farm "problem"
Most people would probably be suprised to know that all the Fish Farms in British Columbia would easily fit into Stanley Park.
How big a problem is the waste from open net fish farms. The Fisheries Act states that "it is unlawful to deposit deleterious substances into water frequented by fish." If it was a problem, the Fish Farm owners would be charged.
If the waste from Fish Farms was a problem, would it not affect the fish in the Fish Farms?
The public is given a highly distorted view of the situation. It is regrettable that we do not get balanced information on the topic.
For a better world
1 year ago
Your shooting the messengers
Illahie, from the tone of your comments you don't like the message, Crawford Kilian or Alexadra Morton. You are also treating the other noted scientists Michael Price and John Reynolds with the same contempt.
Do you have vested interests in the fish farm industry, and that is that what you are trying to protect?
As far as charging Fish Farm for depositing deleteious substances, DFO and their political masters are loathe to charge these businesses. Often when enforcement agencies want to curb undesirable behaviour, if they reccognize it, they pursuade change rather than issue charges.
I'll ask John Reynolds for a personal opion next time I see him.