fish farm siting criteria & politics

[agentaqua]

gimp, you write:

quote:
I have a question. I am looking for information on the hatching times for sealice. I know they are in egg sacks attached to the mother but do they really release and free float or do they hatch right from the egg sack

The best answer I have - is that the egg strings can detach when they are nearing their hatch time, and they sink (not float); but are not particularly heavy, and could be transported some distances - not sure how far - depends on currents.

The egg sack could be thought as a long tube of tennis balls, where the balls (i.e. nauplii) roll out the far end (which splits open) at maturity. The egg strings that are sandy-coloured (not white), are ready to go.

Other info you may find helpful:

The lifecycle of the parasitic copepod (Lepeophtheirus salmonis) consists of 2 planktonic naupilus stages, 1 infective free-swimming copepodid stage, 4 attached chalimus stages, 2 mobile preadult stages, and 1 adult stage (Bjorn and Finstad 1997). Typical development time from egg to adult is 38 days at 10oC (Finstad 2002). Adult sea lice survive up to 22 days off their host and have a life span on a host in seawater for 75 days at 9-10oC; or 191 days at 7.4oC (Pike and Wadsworth 1999).

One gravid Lepeophtheirus salmonis female louse (on Atlantic salmon) has ~300 eggs per female (Johnson and Albright 1991)., with egg to adult survival typically around 40% (Finstad 2002). Sea lice can survive in freshwater for up to 3 weeks, with 60% survival for up to 1 week, although development stops at 16‰ (Finstad 2002).

The eggs survive and hatch at 15‰ but survival of nauplii is nil; complete development occurs only at salinities >30‰ (Pike and Wadsworth 1999). The nauplii survive best in sea water; copepodids at 15‰; the survival of copepodids is higher at 15oC than at 5oC (Pike and Wadsworth 1999).

The copepodids remain infective for 4-6 days at 15oC (Pike and Wadsworth 1999), and have an infection success rate of 65% on wild sea trout (Salmo trutta) in Ireland (Bjorn and Finstad 1997).

 

[gimp]

Aye….. Thanks I am more familiar with the rest of the life cycles as I have been trying to educate myself better on sea lice. It's just been difficult finding info on the hatching and gestation periods. You are a wealth of knowledge Aqua

thanks

 

[OneWay]

Start sending letters and e-mails to our premier (gordon.campbell.mla@leg.bc.ca )and to Pat Bell ( pat.bell.mla@leg.bc.ca) Voice your concerns...tell them what you'll be voting if something isn't done before our last wild BC salmon dies.

Here's a quick way to get your MLA's email address:

http://www.leg.bc.ca/mla/3-1-1.htm

 

[agentaqua]

quote:Originally posted by gimp

Aye….. Thanks I am more familiar with the rest of the life cycles as I have been trying to educate myself better on sea lice. It's just been difficult finding info on the hatching and gestation periods. You are a wealth of knowledge Aqua

thanks

No Probs Gimp. Go get them...

 

[agentaqua]

Further to my previous posting where I briefly commented on the development of DFO (only since 1979) as the main organization to both regulate fisheries and perform fisheries research, and the subsequent dismantling and disintegration of the Fisheries Research Board (FRB) of Canada (in 1979) – I’d like to share what I’ve been able to piece together for everyone.

The reason I think it is important, is that we are dealing with the effects of that decision today within the science, funding, and management of our fisheries resources – including assessing and managing the impacts of the open net-cage industry today.

I believe the way forward is to learn from our mistakes, and take back the management of our resources.

Well, what was the Fisheries Research Board of Canada (for those who are not old enough to remember)?

The Fisheries Research Board of Canada was an independent fisheries science advisory and research agency of the federal government. Its job was to carry-out independent, peer-reviewed science for the benefit and management of Canada’s aquatic resources.

Fisheries management decisions were purposely outside of the purview of the Fisheries Research Board, and were most often delegated to the the Department of Marine and Fisheries (Circa 1898, divided into separate Fisheries and Marine Services in 1930), Fisheries Patrol Service after 1910, The Department of Fisheries and Forestry (1969-1971), or (1971-1979) to the Department of the Environment.

This separation between science and fisheries management was deliberate; which then allowed independent research into fisheries matters. Everyone understood the checks and balances necessary for good governance and democracy to function.

The work that the Fisheries Research Board of Canada did – was by all standards – world-class, ground-breaking, and enviable. So enviable, that I believe – was its demise. Government found it hard to silence or restrict its findings.

The Fisheries Research Board of Canada had a long history. It earliest beginnings started through a Board of Management of the Marine Biological Station in 1898 for a laboratory on a barge in the Gulf of St. Lawrence (Johnstone, 1977). This was followed by the Go Home Bay station in Georgian Bay in 1901 and permanent stations in St Andrews, New Brunswick and Nanaimo, British Columbia in 1908. The Biological Board of Canada was then established in 1912.

In the 1920s, the board hired full-time employees and opened laboratories concerned with the fishing industry and food processing. Investigations began into practical fisheries problems. By 1937, when the Biological Board of Canada became the FRB, it had a distinguished record of marine biological and physical oceanographic research, and was eventually placed under the wing of the National Research Council.

After WWII the FRB opened new laboratories and expanded its work on physical oceanography, Pacific salmon, Atlantic fish stocks and eastern Arctic marine biology. From the 1950s through to the early 1970s – Canada has such a world-class fisheries science that it drew world-class scientists from all over the world (and many ground-breaking fisheries science papers were published); either in its employ directly, or to work with the acknowledged world-class Fisheries Research Board scientists.

Those names of those prestigious scientists live on today, often as names of research vessels or research institutes. Every one of those scientists also trained and motivated many other younger scientists in Canada, who then went onto serve Canada’s science needs and reputation with honour and distinction. This legacy was truly something that every Canadian had a right to feel proud of.

The names of a few of those eminent fisheries scientists included:

1. Dr. W.B. (Bev) Scott – has a research vessel named after him; wrote the bibles for Canadian fish ID and life histories which are still used today, including: A.H. Liem and W.B. Scott. (1966) Fishes of the Atlantic Coast of Canada; W.B. Scott and M.G. Scott. 1988. Atlantic Fishes of Canada; W.B. Scott and Dr. E.J. Crossman. 1973. Freshwater Fishes of Canada; and many other publications.
2. Dr. Archibald Gowanlock Huntsman - who has a marine research facility named after him, due to his ground-breaking work; served as the board's scientist, curator, director, editor and consulting director from 1934-53.
3. Dr. William Edwin Ricker OC, FRSC, LLD, DSc – the very same famous scientist who invented the of the Ricker Curve for describing fish population dynamics – still used by fisheries managers today,
4. Dr. Wilfred Templeman – A pioneer in the scientific study of the Newfoundland fishery. In 1982 a fisheries research ship was named in Wilfred Templeman’s honour.
5. Dr. Michael Smith - Won the Nobel Prize in chemistry in 1993 for discovering site-directed mutagenesis: that is, how to make a genetic mutation precisely at any spot in a DNA molecule. In 1961 Smith took a job as chemist at the Fisheries Research Board of Canada laboratory in Vancouver and published many papers about crabs, salmon and marine mollusks.
6. Dr. Frederick Ernest Joseph Fry - Developed a model for estimating fish populations using VPA (virtual population analysis). This is the same type of analysis that both Krkosek and Ford used to assess open net-cage salmon farming effects.

Truly, an illustrious history to be proud of. You can compare where we have slid with our fisheries science since then; when you look at the “science” DFO has been using since then to try to prop-up the defense of the open net-cage salmon farming (we discussed many examples in the past postings). What will be DFO’s legacy now, in comparison? Something to be proud of?

So, how did it happen? How was the Fisheries Research Board of Canada dismantled? How was DFO constructed? What reasoning did they use? Who did it? – and why? Most importantly - what can we do to take back the management of our resources from DFO?

 

[sockeyefry]

Agent,

I agree with you that we should have never gotten rid of the FRB. DFO should have its mandate to regulate fisheries. It should not have any function in the development of aquaculture. That should be the domain of say Agriculture Canada.

If the FRB was doing the research about sea lice under the old format, there would be less doubt of its authenticity by people such as yourself. As much as I say that Morton and Krkosek are controlled by anti agenda, you also have pointed to the same for DFO. I find it unfortunate that agendas tend to cloud conclusions, and a lot of "science " is done to provide evidence, or support a position, rather than simply finding out about something.

 

[agentaqua]

DFO lies said to be root of a bigger problem; [Final Edition]
Neil Frazer. Courier - Islander. Campbell River, B.C.: Mar 29, 2003. pg. A.10 (Copyright Courier-Islander (Campbell River) 2003)

It's often forgotten that BC's wild salmon fishery is a form of aquaculture in which you take care of the rivers and then you harvest the salmon when they come home.

The history of this type of aquaculture shows the need for humility in fisheries science and why we should be suspicious of convenient beliefs.

A century ago, for example, salmon canners said that salmon didn't care which stream they went up to spawn, so it was OK to catch every salmon in the most convenient stream. It wasn't until 1920 or so that science was able to show that most salmon return to their natal streams to spawn.

About fifty years ago governments decided that salmon could be produced by hatcheries, so we didn't need rivers to make salmon. This was convenient for loggers and dam builders, but it hasn't produced salmon, mainly because scientists don't understand salmon well enough to successfully breed them over a long period.

Until recently, the big salmon canners assured us that very few spawners were needed in a stream, so they could let a few necessary spawners go up, and then catch every salmon that came later. Science has only recently shown that the carcasses of extra spawners feed the microscopic creatures that salmon fry eat after they hatch. If you let some extra spawners go up the river in the fall, more fry survive in the spring. (Putting dead salmon in the stream has the same effect, which is how scientists proved the concept.)

In its time, each of the bad ideas noted above was championed by industry and government with the same fervor now reserved for open netcage salmon farming.

If you've read this far, you know why biologists tend to be more humble than engineers. Biologists know that it is better to work with nature as much as possible rather than trying to replace nature. In the case of salmon, that means it is better to try to give salmon the kinds of streams they prefer, even though we don't know exactly how those streams work, rather than trying to duplicate everything that happens in a stream.

Now let's look at open netcage salmon aquaculture (ONSA). Politicians and industry love ONSA the way they once loved hatcheries, which ought to make you suspicious right away. They love it because it creates jobs (in the short term), it's capital intensive (and thus good for big companies), it's easy to automate (making everyone feel very modern), and it removes the need for rivers (loggers and dam builders like that).

British Columbians love their wild salmon, so there was some early resistance to ONSA. Many of Canada's fisheries scientists didn't like it because they knew of the problems it had caused for wild fish in Europe.

Also, they did some experiments: When they raised sockeye in a tank on land the sockeye did fine, but when they tried raising them in an ocean netcage the sockeye all got sick and died.

However, politicians trying to push ONSA had one big asset, which is Canada's Department of Fisheries and Oceans (DFO).

DFO was created in 1979 to prevent fisheries scientists from contradicting the Minister of Fisheries. Before DFO was created, money for fisheries science was distributed by other scientists through organizations like the Fisheries Research Board. Fisheries scientists weren't required to agree with the Minister, and the public had access to their research.

Politicians hated the Fisheries Research Board, but Canada had the best fisheries science in the world because of it.

To make a long story short, the politicians sold ONSA to the public by forcing DFO to lie. Politicians and the ONSA industry now go around quoting the lies as science. This strategy succeeded remarkably well because people do not expect government scientists to lie.

Most of the lying at DFO is done by DFO Aquaculture. Two techniques are mainly used. One technique is to tell half the truth (the unimportant half), and the other technique is to promote phony science like the BC Salmon Aquaculture Review (SAR). Politicians can then go around citing the phony science as if it were real science.

The first lie promoted by DFO is that it's unlikely that wild fish get disease from farm fish. The truth is that farm salmon are exposed to disease from adult wild salmon swimming by the netcages on their way to the rivers in the fall. If the farm salmon get the disease, as sometimes happens, then juvenile wild salmon are exposed to that disease when they swim past the netcages on their way to the ocean in the spring. The farm salmon don't always get disease from the adult wild salmon, and they don't always give it to the young wild salmon, but that's the way to bet.

Medicating sick farm salmon keeps them alive, which is helpful to farmers, but it never quite eradicates the disease, so it isn't much help to wild salmon.

The second lie promoted by DFO is that the probability of colonization by Atlantic salmon (the species of choice in BC netcages) is insignificant.

The important part of the truth is thatif you are continually introducing Atlantics by escapes, the probability of colonization grows exponentially with duration and eventually becomes significant. The other important part of the truth is that regular escapes of Atlantic salmon are a de facto colonization.

Colonization by Atlantics is an issue because Atlantic salmon aren't susceptible to exactly the same diseases as Pacific salmon. Thus it is possible for Atlantics to spread a disease that doesn't kill them, but kills Pacific salmon. (If this seems unlikely, remember how smallpox and influenza decimated BC's First Nations and that they still haven't recovered.)

Occasionally DFO Aquaculture deceives people by pretending to be doing something it is not actually doing. For example, in the spring of 2001 young pink salmon became mortally infested with sea lice while migrating past salmon farms in BC's Broughton Archipelago. The species of sea louse responsible (Lepeophtheirus salmonis) is a common salmon farm pest that has never been known to infest young wild salmonexcept when they happen to be near salmon farms. The part of DFO responsible for wild salmon should have immediately investigated this, but they didn't.

They let DFO Aquaculture conduct the investigation. This is like sending a fox to look for missing chickens.

DFO Aquaculture waited three weeks (giving the infested young wild salmon time to die or migrate out of the area) and then went up to the Broughton and dragged a trawl net in deep water, well away from the shallows where young pink salmon are found. The DFO pathologist assigned to count the lice refused to sign the count because the net was dragged at a speed that would have removed many of the lice. DFO published a report saying sea lice levels were normal, even while salmon farm operators were telling them that sea lice levels were high. The investigation was a sham.

The men who perpetrated it are clever men who knew what they were doing. (I know they are clever because I've read their scientific papers.)

Why haven't fisheries scientists at the University of British Columbia and Simon Fraser University blown the whistle on DFO Aquaculture? Actually, they have, but they've been so polite about it that hardly anyone noticed.

University professors know that if you want to study fish in Canada you have to get along with DFO because DFO controls most of the research funding and research facilities. You can't take a fish out of the water without a permit from DFO.

Why doesn't DFO management stop DFO Aquaculture from lying to the public?

At the level of the working scientist DFO has many excellent people, but the upper management of DFO science is very weak. It consists of nice men and women who arrived at their present positions by not contradicting politicians. Remember, DFO was created in 1979 to stop scientists from contradicting politicians. Present DFO management came up through that system.

DFO management also wants to believe in ONSA because DFO has been such a failure at managing fisheries. (As far as I know, the only BC fisheries doing well are black cod, probably because it is managed by black cod fishermen, and halibut, which is managed by international agreement.)

Desperate for success, DFO management lurches from one bad idea to another like an investor who buys one bad stock after another and never learns from his mistakes. The difference between DFO and the investor is that the public keeps giving DFO more money to lose.

Ironically, while DFO was throwing money at ONSA, wild Pacific salmon have apparently been increasing. The All-Nations catch of Pacific salmon has been climbing since about 1976. Of course, it's a mistake to confuse catch size with population size, but still, there are a lot of wild salmon coming home every fall. Those salmon could be a high-margin business. They aren't a commodity like farm salmon.

Marketing experts tell us that the profits are in branded goods, not commodities. I imagine every stock of wild salmon could be marketed like vintage wine to gourmets all over the world. Remember when Gallo was the only California wine? Look what people pay for California wine now.

The California wine makers got to here from there by cherishing the differences between different grapes and educating their consumers. Fishermen will do the same with wild salmon, given half a chance. It's the kind of salmon aquaculture that's compatible with BC's biggest industry (tourism) and it doesn't require any lying.

(Neil Frazer was born and raised on the coast of BC and returns there every summer to survey the coast from his own little boat. He studied engineering at UBC and geophysics at Princeton. Curently he is a professor in the School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii. His scientific research has been supported by the National Science Foundation, the Office of Naval Research, and the American Chemical Society. He is not financially supported by any environmental organization.)

 

[sockeyefry]

Agent,

Frazer's comments are irrelevent. It is his opinion, and adds nothing to the debate. This was a letter to the editor, which anyone with a pen and a piece of papaer can write. After such a good run with the science articles, you come up with that?

 

[agentaqua]

sockeyefry - you know - your responses are quite predictable.

I found the letter to the editor by Neil Fraser while I was looking for more info on the Fisheries Research Board, after my posting about the same. I threw it in - not only because it contained many good points to consider for everyone on this forum - but also to see if you would try to discredit the letter by the association of the author. You did.

I noticed that you initially agreed with my last posting on the Fisheries Research Board, but when you saw Neil Fraser's signature on the letter (which agreed with both our comments on the Fisheries Research Board), you responded with:

quote:Frazer's comments are irrelevent. It is his opinion, and adds nothing to the debate. This was a letter to the editor, which anyone with a pen and a piece of papaer can write. After such a good run with the science articles, you come up with that?

Fraser's comments on DFO and the Fisheries Research Board are anything but irrelevant in the context of our discussions.

I feel that you have bought in fully to the pro-fish farm lobby's vitriol and propaganda by attempting to discredit the author; rather than disagree with the posting, using logical arguments, back by science and references. At least you have continued to demonstrate this common methodology utilized by the pro-fish farm lobby to everyone else who reads this forum. Thanks for that, at least.

 

[gimp]

Calculating the true cost of salmon farming
By Chris Genovali

There has been a strong push recently by governments in both the United States and Canada for citizens to increase their fish consumption because of health benefits. This presumptive dietary shift, along with the fact that the bulk of seafood caught in Canadian waters is exported, serves as the raison d’être for the development of the salmon-aquaculture industry.

“We need to meet the seafood demand” is the mantra of eager government and industry representatives who are keen to reap the associated profits. But the first question is whether or not the demand for species such as salmon, tuna, halibut, and cod is actually sustainable. Is it really possible for these species to “feed the world”, as the industry’s proponents are wont to assert?

In order to farm salmon, harvesting of wild fish (for example, sardines, whiting, and anchovies) for fishmeal and fish oil is required to produce the feed. A recent report by the International Council for the Exploration of the Sea suggests that deep-sea fish in the North Atlantic are being fished at more than twice the rate they can withstand to provide food for farmed salmon. While the debate over local impacts continues, the global impacts of salmon farming have received little attention in British Columbia.

Let’s consider the ecology of farming carnivores like salmon. Corey Peet is an ecologist researching the impacts of aquaculture on the marine environment. As he explains: “Natural food webs take the shape of a pyramid. At the bottom of the pyramid lies an abundance of organisms that gain their energy directly from the sun or chemical processes. The next step up the pyramid are the slightly less abundant organisms, mostly herbivores, that feed on those below them. With each step up the pyramid, only 10 percent of the energy is passed on to the next step, as 90 percent of energy is lost to heat. Therefore, fewer organisms can be supported as you step up the pyramid, leaving only a few predatory species at the apex. In other words, there is a reason why we only see a few carnivores in the wild; nature only has so much energy to go around. Thus, when we consider the farming of salmon against the fundamental basics of ecology, it makes no sense to claim that this practice is sustainable.”

(On a related note, Agriculture Minister Pat Bell should be commended for instituting a moratorium recently on fish farm expansion for B.C.’s north coast, although the province simultaneously approved two new farms for the south coast.)

Leading fisheries experts—such as Daniel Pauly of the UBC Fisheries Centre—caution against “farming up the food web” because of the inefficient and wasteful use of biological resources, all of which are already used by humans and other organisms, and some of which are commercially valuable. Recent estimates indicate that farming salmon requires anywhere from two kilograms to four kilograms of wild fish to produce one kilogram of farmed fish. In contrast, farming herbivorous species (like tilapia and carp) requires minimal inputs of fishmeal.

With the majority of the world’s fisheries in crisis, scientific evidence suggests that salmon farming is hurting more than helping the global fishery problem. In fact, the volume of harvested fish required to support the salmon-farming industry in Europe is larger than the productivity of the entire North Sea, requiring the industry to depend heavily on fishmeal imported from South America. The practice of taking protein sources from impoverished countries in the Southern Hemisphere to produce a luxury product for populations in western countries raises significant ethical as well as ecological concerns. Although the industry will claim that it is continuing to lower its dependence upon marine-derived protein through the development of alternative feeds (such as soy protein), these gains have been offset by the rapid growth of the industry.

Peet also points out that more than 85 percent of the world’s aquaculture production (primarily in Asia) involves the use of noncarnivorous species (freshwater fish, shellfish, and seaweed), and this has resulted in global aquaculture production adding to world seafood supplies. However, while the global aquaculture industry is a net fish-protein producer, aquaculture of carnivorous fish is a net fish consumer. The rapid expansion of the farming of salmon and other high-value carnivorous species (tuna, halibut, black cod) is occurring mainly in the industrialized countries where the fish are primarily consumed. The reality is that the salmon-aquaculture industry is being driven by short-term economic motives and not the lofty egalitarian goal of “feeding the world”.

Past and current scientific information suggests that farming salmon and other carnivores is not sustainable, contrary to government and industry claims. Salmon farming is not feeding the world but, in actuality, is doing the opposite: it takes resources from poor countries to produce a luxury item for consumers in rich countries. With the growing concern about sustainability issues on a global level, we must ask ourselves if we should be supporting industries that take more than they give back.

 

[agentaqua]

Thanks for the last posting, Gimp (Calculating the true cost of salmon farming By Chris Genovali).

Let's see if we can predict sockeyefry's response:

* Chris Genovali is part of Raincoast Conservation - one of those terrible eco-freaks from a terrible eNGO,and
* Chris has the feed conversion ratios all wrong, and
* deny that feeding carniverous salmon is a net loss of protein out of the ocean.

Okay - So now I'm ready to be proven wrong and apologize for assuming sockeyefry's response. Go ahead sockeyefry. Let's hear your side.

 

[Dave H]

Here he comes now.

 

[Nimo]

OK, I've tried to resist and apologize in advance[V] Is that who shot SFK?[]

 

[finaddict]

CRRRRRRAAAAAAZZZZZZZZZZEEEEEEEEE

VAAAAAAAAARRRRRRRRMITTTTTTTTS!!!!!!!!!!!!!!!

 

[gimp]

hey aqua whats your take on this (just another politician lying?)

A smart parasite doesn’t kill its host, said Ron Cantelon.

That fact is important to remember, the Nanaimo-Parksville MLA said last week, in relation to a decision to halt approvals of fish farms on B.C.’s north coast.

Cantelon said recent studies cast doubt on claims of mortality among parasite-attacked salmon smolts running as high as 90 per cent, and the basic reality of life as a parasite is one reason why.

“Think of a parasite that’s latched onto a fish that’s dying and toxic,”

he said. “It would affect the lice.”

Cantelon cited a study by the Pacific Salmon Foundation that indicated mortality rates significantly below those suggested in high-profile research by fish farm opponent Alexandra Morton.

“This group of scientists went up and dipped nets to get fries, much the same as Alexandra Morton, but instead of putting them on the dock, where the sun changes the temperature in the tank, they put them into a lab, where they could maintain ocean conditions,” Cantelon said. “Only about 30 per cent of the fish had attachments, one or two lice on them. In two weeks, the lice fell off. They just dropped off.”

Cantelon said the fish showed no changes in their body chemistry, with the exception of their glucose levels, which dropped, and then rose back to normal levels once the lice were gone.

“There were no other pathological abnormalities whatsoever,” he said. “The ones with lice on them had no impairment of mobility whatsoever.”

The research, he said, casts doubt on the widely-held belief in the harm done by fish farms to migrating salmon fry.

Rather than closing fish farms, he said, people who want to save the wild salmon have a better, more efficient option.

“Stop hunting them commercially for food. They are the last wild animal we hunt commercially for food.”

The halt to fish farm approvals on the north coast, he said, was one of the recommendations put forward by the sustainable aquaculture committee, but he said it’s likely going to be the only one that gets implemented.

“I don’t anticipate any other recommendations being implemented,” he said.

That doesn’t sit well with Alberni-Qualicum MLA Scott Fraser, who also sat on the committee.

While Fraser called the halt a good first step, he also wants to see fish farms in the Broughton Archipelago to go fallow.

“There’s a real gauntlet the pink and chum salmon have to run there and the chance of exposure is huge,” he said. “All the peer-reviewed science that’s coming out says wild pinks in the Broughtons are in severe danger of extinction and the minister’s alternative was to use more SLICE, which is a neurotoxin used to control sea lice.”

This compound, he said, is toxic and illegal to use without a special warrant from a veterinarian. Not only does it kill sea lice, Fraser said, but it also impacts on other species.

“Prawn fishermen said they saw a direct impact on their fisheries because of the use of SLICE,” he said. “It kills not only sea lice, but potentially larval prawns as well.”

 

[sockeyefry]

The statement he makes is true, that a successful parasite wants to live off of, but never kill its host. Unfortunately in nature, things don't necessarily go according to the "book". Parasites sometimes do kill their hosts. In additon, parasite loads which, according to the Book, are supposed to kill hosts don't.

There exists some debate regarding how many sea lice does it take to kill a salmon fry. I do not believe there is a definitive answer to this important question. Images of fry with "bugs" on them certainly look horrific (and are intended to be so for the desired reaction), but in reality may represent an entyirely survivable condition for the fry. It has been suggested that pacific and atlantics have different susceptibility to lice loadings, and that a number of lice which would kill an atlantic wouldn't cause a pacific any problems. I think it had something to do with the growth rates of the different fry, and that the pacifics outgrew the lices effects.

Aqua Do you have any Lice load lethality studies at your disposal?

It seems that Cantelon has some reservations regarding Morton's methodologies. If he is correct, then leaving fry in tanks in the sun certainly would shorten their live span, irregardless of how many lice they had on them

Scott Fraser made the comment:

"he (Fraser) said. “All the peer-reviewed science that’s coming out says wild pinks in the Broughtons are in severe danger of extinction"

This is not an accurate statement, as to my knowledge there has been only 1 such study, the conclusions of which have been called into question. In addition, population counts of salmon in the last 50 years indicate actually the opposite, that since farms have been in the Broughton, the population has actually increased. Now I am sure that it is due to probably better practises in the watersheds, and a reduction in commercial fishing, but I think I'll claim that it is because of Salmon farms that the highest runs of Pinks on record occurred in the Broughton. Think I'll get media attention, probably not. Not doom and gloom enough, I guess

BTW, Nice picture of Yosemite Sam, and nice Pun Nimo. Who shot SFK? LOL

 

[agentaqua]

sockeyefry - the best numbers I can find on numbers of lice per gram of fish that can cause mortality are in the range of 0.7 – 1.6 lice per gram of fish. The 1.6 lice/g reference is from Bjorn and Finstad (1997) work on sea trout, while the 0.7 lice/g reference is from McKinley et al. (2002).

This means that for the small, outmigrating pink and chum smolts - they would need only an average of some 1-2 lice/fish to cause population-level effects. Krkosek et al. (2007) field work findings concur with these hypothetical levels.

gimp - good posting.

Ron Cantelon was the BC Liberals plant (the BC Liberal Party contributed over $70,000 to his 2005 election campaign) on the Committe on Sustainable Aquaculture. Ron's riding is "NANAIMO" - home of PBS Nanimo, BC Centre for Aquatic Health Sciences (http://www.cahs-bc.ca/), Malasipina University College with their aquaculture prorams, etc.

Okay - so having stated some of the more obvious biases that we can find - is there any validity in his arguments?

quote:A smart parasite doesn’t kill its host.”

Parasites (at least the non-human ones) are not inherently "smart", or "dumb". The system that they have evolved into, normally has built-in checks and balances. Disrupting these balances (like providing a place for large quantities of overwintering lice on farmed fish in open net-cages) dramatically alters the balance. See Neil Fraser's explanation of this, on this forum.

quote:“Think of a parasite that’s latched onto a fish that’s dying and toxic,”he said. “It would affect the lice.”

Duh!! - lice loading also affects so-called "healthy" fish. Called sub-lethal or causes of morbidity - which affects both growth and survival rates. Healhy fish are not immune from the effects of sea lice (although they may live slightly longer); it's the larger fish that can take more lice.

quote:Cantelon cited a study by the Pacific Salmon Foundation that indicated mortality rates significantly below those suggested in high-profile research by fish farm opponent Alexandra Morton.

Cantelon said the fish showed no changes in their body chemistry, with the exception of their glucose levels, which dropped, and then rose back to normal levels once the lice were gone.

“There were no other pathological abnormalities whatsoever,” he said. “The ones with lice on them had no impairment of mobility whatsoever.”

I believe he is talking about the study "B.14 Effects of sea lice on the physiology and health of pink salmon", p.32
(http://www.pacificsalmonforum.ca/pdfs-all-docs/2007InterimFindingsFeb8-08.pdf).

First-off - it's not peer-reviewed (not yet, anyways). Thought we were going to call peer-review articles "science", and everything else "opinion". If this is of peer-review quality - then the authors should submit it - and then we will talk about it as science. To just say "a study" here or there is very disingenuous and misleading.

I noted some very important additional "facts", not relayed by Cantelon:

1/ "Duration of survival [of infected smolts] decreased with increasing lice loads but artificial infections were deemed to have been too high to make any comparisons with natural lice infection rates in juvenile salmon" - very important point!!! yet Cantalon is tryin to make that comparison.
2/ "A relationship was observed between increased mortalities of pink salmon when lice enter a moulting stage of their development" - yes, that relationship is that lice eventually kill the fish, they just admitted it - we already spoke about this in earlier postings.
3/ "Skin lesions and lower glycogen stores were associated with the presence of sea lice". - Why not call it what it is - sub-lethal and morbidity effects were noted. Yet Cantelon boldy lies: "There were no other pathological abnormalities whatsoever". They also did not look at the other physiological factors such as plasma chloride levels, lactate levels, or cortisol levels - why the H**L not? Didn't want confirmation?
4/ "Water temperature increased (from 8.5oC to 12.5oC) and salinity decreased (from 26 ppt – 19 ppt)".

Did you get this last point???

Salinity was decreased (purposely???) from 26 ppt to 19 ppt. WHY THE H**L did they do that? Why didn't they keep the salinity at 29-30 ppt? A "mistake", perhaps???

We know that complete development of sea lice occurs only at salinities >30‰ (Pike and Wadsworth 1999). Did they purposely attempt to skew the studies of the findings? Did they try to kill-off the lice? Looks like they succeeded.

That's where the peer-review process would question the findings of this report.

It doesn't really add much to the available science. taxpayer monies wasted again.

 

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Dang you beat me

Actually he said. A smart parasite doesn’t kill its host. So I wonder what studies Ron has to show how smart or dumb a sea lice is. Can they communicate with each other? Example (One sea lice says to the other sea lice "hey get the hell off my salmon!!!! There are too many here already and our meal ticket is goanna die or get eaten by a larger predator cause we are weighing him down and stealing valuable life blood outta this guy!!!) Do you know what a low glucose level in humans does?????? Its called Hypoglycemia. What are the symptoms from human hypoglycemia? Trembling, anxiety hunger, and heart palpitations. Because the brain is deprived of glucose, a second set of symptoms follows, difficulty in thinking, confusion, seizures, coma, and untreated…. death. I believe that Cantelon has not studied Morton's methodologies fully and is talking out his butt. You state,
"It has been suggested that pacific and atlantics have different susceptibility to lice loadings, and that a number of lice which would kill an Atlantic wouldn't cause a pacific any problems. I think it had something to do with the growth rates of the different fry, and that the Pacific's outgrew the lice effects.

I must agree and disagree Atlantic's are more likely susceptibility but they are also not place in a net pen until their 12 to 18 months old while Pacific's (pinks and chum) are leaving the rivers after 3 weeks. That is a big difference. So how can you truly compare Atlantic's to Pacific's? Unless Atlantic's are spawning and coming out of the rivers passing by the same fish farms. That’s not something any of us want to see

 

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quote:Originally posted by agentaqua

4/ "Water temperature increased (from 8.5oC to 12.5oC) and salinity decreased (from 26 ppt – 19 ppt)".

Did you get this last point???

Salinity was decreased (purposely???) from 26 ppt to 19 ppt. WHY THE H**L did they do that? Why didn't they keep the salinity at 29-30 ppt? A "mistake", perhaps???

We know that complete development of sea lice occurs only at salinities >30‰ (Pike and Wadsworth 1999). Did they purposely attempt to skew the studies of the findings? Did they try to kill-off the lice? Looks like they succeeded.

That's where the peer-review process would question the findings of this report.

It doesn't really add much to the available science. taxpayer monies wasted again.

Anyone had or have a saltwater fish tank. I have a 150 gallon salt water reef tank and I can tell you if I let my salinity get out of the desired range my tank goes bonkers. IT doesnt take long to kill fish of if your salinity drops more that 6 to 7ppt. The range I like to keep it is 30 to 34 ppt. If I let it go down to say 23 to 27ppt stuff starts to die.


http://www.nodc.noaa.gov/cgi-bin/OC5/WOA05F/woa05f.pl?navigation=s_0_0_2_up

 

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Some time later this year, federal regulators will vote on allowing commercial fish farming in the Gulf of Mexico. Before they decide, they should consider the cautionary tale of Chile's aquaculture industry. Once-pristine coastal waters of that country's Gulf of Reloncavi are now seriously degraded by pollution from unchecked salmon farming.

Raised in closely packed pens the size of houses, farmed salmon became Chile's third-largest export industry, with much of it entering the United States. Then the fish started dying off by the millions from a viral plague called infectious salmon anemia, the New York Times reported. Not only have hundreds of fish farming workers lost their jobs, but wild fish stocks in the area have been decimated as well.

"All of these problems are related to an underlying lack of sanitary controls," said Dr. Felipe Cabello, a professor who has studied Chile's fishing industry.

Fish kept in such confining conditions become stressed and must be fed high doses of antibiotics. Both fish waste and excess food release parasites, drug-resistant diseases and contaminants into surrounding waters. Local fisherman near the farms have seen a sharp drop-off in wild-fish stocks and an unnatural appearance of their catch from the colorant used to make farmed salmon flesh appear healthy.

Chile's fish farming problems might be more acute than those in other places, but they are hardly unusual. Salmon farmed throughout the North Atlantic have been stricken with a similar virus. Such outcomes have led Wolfram Heise, director of a marine conservation project in Chile, to a sobering conclusion: "It is simply not possible to produce fish on an industrial scale in a sustainable way."

Those hoping to farm the gulf will undoubtedly argue that the outcome will be different here. With fish farms farther from shore, currents would disperse the waste and contaminants, advocates say.

Maybe not, says a Pew Oceans Commission report. A 200,000-fish farm produces fecal waste equivalent to the raw sewage from 65,000 people, and the pollution spreads 500 feet beyond each site.

The Gulf of Mexico Fishery Management Council will take up proposed fish-farming regulations this summer, after which the National Oceanic and Atmospheric Administration will make the final decision. Before regulators approve fish farming here, they ought to visit Chile, but be wary of the poached salmon on the menu.