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Author Topic: Lethal virus from European salmon found in wild BC salmon  (Read 245520 times)

alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #495 on: January 04, 2012, 07:25:46 PM »

Interesting smorgasbord of diseases the salmon feedlots are breeding...
 
Gill Disease (Proliferative Gill Inflammation
Epitheliocysts/Chlamydia & Amoebic Gill Disease)
Paranucleospora theridion
Parvicapsulosis (Parvicapsula pseudobranchicola/Paranucleospora theridion)
Gyrodactylus (‘Salmon Killer’)
Furunculosis (Aeromonas salmonicida)
Infectious Hematopoietic Necrosis (IHN)
Viral Haemorrhagic Septicaemia (VHS)
Cardiomyopathy Syndrome (CMS)
Heart and Skeletal Muscle Inflammation (HMSI)
Plasmacytoid Leukemia (Marine Anemia)
Bacteria Kidney Disease (BKD)
Myxobacterial Infection (Piscine Tuberculosis)
Spironucleosis (Spironucleus salmonicida)
Francisella (Francisellosis)
Yersinia ruckeri (Yersiniosis/Enteric Redmouth/ERM)
Flavobacterium psychrophilum (Bacterial Cold Water Disease/Rainbow Trout Fry Syndrome)
Vibriosis (Cold Water Vibriosis/Hitra Disease)
Moritella Vicosa (Winter Ulcer)
Hemorrhagic smolt syndrome (HSS)
Mad Fish Disease
Botulism (Clostridium botulinum)
Parasitic Meningitis
Costia (Ichthyobodo species)
Tapeworm (Diphyllobothriasis)
Microsporidian encephalitis
Nephrocalcinosis (urolithiasis)
Malignant Intestinal Tumours
Desmozoon lepeophtherii (Paranucleospora theridion) & Autumn Disease and Salmonella.

It's easier to understand why they need to use all those antibiotics.  ::)

Edit: I missed Infectious Salmon Anaemia (ISA) and Infectious Pancreatic Necrosis (IPN)
« Last Edit: January 04, 2012, 07:31:39 PM by alwaysfishn »
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Sandman

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #496 on: January 04, 2012, 07:53:19 PM »

That chart IS a correlation.

What exactly IS the correlation you refer to?  That the Sockeye began their precipitous decline in 1993, falling from an average return of 6 million fish over the previous 15 years (1977-1993) to a low of just over a million fish in 2008 (15 years later) at the time when the Alaskan releases stabilized at an average of 1.5 billion fry (an average that was maintained over 15 the years of the sockeye's steady decline (note there was no steady decrease over the 15 years that the releases were steadily increasing by over 1000% (from 1 million released in 1977 to over 1.4 billion released in 1993), and it was not until the numbers of fry released stabilized at an average of 1.5 billion that the steady decline began). Is THAT the correlation to which you refer?  It would seem to me that a "correlation" would be reflected if the chart showed a steady decline in return as the numbers of fry released increased (this would be a "negative correlation" where function a changes in an opposite response to function b, as opposed to a "positive" correlation where function a increases as function b increases or visa versa).
« Last Edit: January 04, 2012, 07:59:10 PM by Sandman »
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #497 on: January 04, 2012, 09:02:15 PM »

I thought that was rather self evident. The chart correlates the trends in hatchery releases to the trend in sockeye returns.
« Last Edit: January 04, 2012, 09:10:45 PM by absolon »
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #498 on: January 04, 2012, 09:24:55 PM »

I thought that was rather self evident. The chart correlates the trends in hatchery releases to the trend in sockeye returns. You seem to be venturing into the area of attempting to interpret the trends. As I mentioned earlier, I would consider any effort to interpret the meaning of the trends based exclusively on the minimal amount of knowledge provided by that chart to be a fool's errand so I'm happy to leave it to others who find the task rewarding.

It kind of detracts from the shock value of that headline when i) you see the paper and the article was published in 2008, ii) you realize that it is based on a statistical evaluation of gross trends and doesn't take into account trends that existed prior to salmon farming or any other factors that would affect wild survival, iii) the study indicates specifically that "In British Columbia (Pacific Canada), only pink salmon showed significant declines correlated with salmon aquaculture." and those results for Pink Salmon are largely based on Kroksek's work.

You're hilarious Absolon. You chastise a poster for quoting an article published in 2008 and then you come on here with a correlation argument using 2 year old data......

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aquapaloosa

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #499 on: January 05, 2012, 07:38:27 AM »

Quote
It's easier to understand why they need to use all those antibiotics.  Roll Eyes

This fish farms I work on have not used antibiotics for 5 years.  If it is festering as you suggest, how come the fish do not or have not been dieing at an accelerated rate at any point during all that time?

AF, no matter how many times you are reminded  about antibiotic use on salmon farms being quite low you insist of reintroducing the idea that it is very high.  It just is not true.


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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #500 on: January 05, 2012, 08:54:51 AM »


AF, no matter how many times you are reminded  about antibiotic use on salmon farms being quite low you insist of reintroducing the idea that it is very high.  It just is not true.


It would be great if we could all accept your word that antibiotic use is quite low, as you seem to be an honest person.....  :D  

It's a known fact that although the salmon farming industry collects disease and antibiotic usage data, not all farms comply with submitting their data (the requirements seem to be voluntary) and the ones that do, likely pick and choose which data they want to send in. When you have a voluntary reporting system like this the data can't be relied on! I suggest that they have little incentive to be honest with their reports as it would affect the marketability of their product.

I realize that DFO audits some of the farms on a random basis, however with the limited resources they have (and less next year) they are auditing a very small percentage of the farms. DFO reports that the antibiotic use is low are just opinions, and probably the equivalent of false advertising for the industry.

Can you provide evidence of accurate reporting by the industry? I need more than just your personal experience on a few farms.
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Bassonator

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #501 on: January 05, 2012, 09:00:17 AM »

It would be great if we could all accept your word that antibiotic use is quite low, as you seem to be an honest person.....  :D  

It's a known fact that although the salmon farming industry collects disease and antibiotic usage data, not all farms comply with submitting their data (the requirements seem to be voluntary) and the ones that do, likely pick and choose which data they want to send in. When you have a voluntary reporting system like this the data can't be relied on! I suggest that they have little incentive to be honest with their reports as it would affect the marketability of their product.

I realize that DFO audits some of the farms on a random basis, however with the limited resources they have (and less next year) they are auditing a very small percentage of the farms. DFO reports that the antibiotic use is low are just opinions, and probably the equivalent of false advertising for the industry.

Can you provide evidence of accurate reporting by the industry? I need more than just your personal experience on a few farms.


Actually AF how about you provide some evidence, I need more than just a trio of fear mongers..... :D
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #502 on: January 05, 2012, 09:21:25 AM »

Actually AF how about you provide some evidence, I need more than just a trio of fear mongers..... :D

Here you go.....  I provided the evidence several days ago. :)


I agree.....   a little poison is your system is a lot more tolerable than a lot of poison.  ::)

I accept that they have been forward with you and open to your questions but I'm not sure why you would bother sharing that irrelevant bit of information.  ???

I don't feel any confidence whatsoever, that they are being forward with the public when reporting (or not reporting) their diseases. It appears the reporting is entirely voluntary and highly likely that the farms having disease outbreaks choose not to submit their data. Makes the data pretty useless!

http://www.agf.gov.bc.ca/ahc/fish_health/BCSFA/BCSFA_Fish_Health_Quarterly_Report_Review.pdf

There are currently 13 companies operating private aquaculture facilities in British Columbia. Eight of these (or 62%) are providing data to the database.

The public sector facilities have agreed to also provide data to the database. As of October 2003, information has been provided from eleven Salmon Enhancement facilities operated by DFO and two FwFS hatcheries. While this does not represent all public facilities, it does provide a sampling of the fish health concerns facing the public sector operations.

It should be noted that in each quarter, the number of facilities providing data (i.e. thesample size) does vary, causing some variation in the calculations and results provided.



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Sandman

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #503 on: January 05, 2012, 04:38:35 PM »

I thought that was rather self evident. The chart correlates the trends in hatchery releases to the trend in sockeye returns.

As I pointed out, there does not appear to be a "correlation" (either positive or negative) between the "trends".  When the releases were increasing (1977 - 1993) the returns were more or less stable, and when the releases stablized (1993 - 2008) the returns were declining.  As I pointed out, a correlation between these trends would show the returns decreasing as the releases increased (a "negative" correlation), or perhaps as the releases increased the returns also increased (a "positive" correlation).   What you seem to suggest is that there is a "negative correlation" whereby when the trend of the releases was increasing the trend of the returns was stable, and then when the trend of the returns was stable, the trend of the returns was declining.  This hardy seems like a correlation at all.  What it appears to be is that both changes in the trends occurred at the same time.
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StillAqua

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #504 on: January 05, 2012, 05:52:18 PM »

As I pointed out, there does not appear to be a "correlation" (either positive or negative) between the "trends".  When the releases were increasing (1977 - 1993) the returns were more or less stable, and when the releases stablized (1993 - 2008) the returns were declining.  As I pointed out, a correlation between these trends would show the returns decreasing as the releases increased (a "negative" correlation), or perhaps as the releases increased the returns also increased (a "positive" correlation).   What you seem to suggest is that there is a "negative correlation" whereby when the trend of the releases was increasing the trend of the returns was stable, and then when the trend of the returns was stable, the trend of the returns was declining.  This hardy seems like a correlation at all.  What it appears to be is that both changes in the trends occurred at the same time.
If you're really interested in the time series data and you have the stomach for some heavy statistical modeling (or just want to read the summary), there is a technical report on the Cohen Commission website that looked at sockeye productivity, competing pink salmon, ocean sea surface temperature conditions and fish farm production over the last 60 years or so. Conclusion is basically, yeah we see correlations but we don't know if they mean anything.
http://www.cohencommission.ca/en/pdf/TR/Project5B-Report.pdf#zoom=100

"The results of this analysis suggest that increasing farmed salmon production, (sea surface temperature) SST and pink salmon abundance increases sockeye salmon mortality. In addition, the influence of aquaculture production on sockeye mortality was predicted to be greater when SST anomalies are negative (i.e., cool for British Columbia populations) and when pink salmon abundance in the North Pacific Ocean is high. However, there was large uncertainty around these estimated effects, which precludes drawing strong inference from these results. The relationships described in this report are correlative, do not on their own establish causation and should be re-examined as more information becomes available."
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #505 on: January 05, 2012, 06:01:36 PM »

The juxtaposition of the two data series shows a common point in time where both trends change. Based on the sparseness of the information presented I can't say that is significant or if it's coincidence, but it certainly catches my eye. I think it is an interesting phenomena and so far, I've run across nothing that indicates the events are unrelated or that would suggest the correlation of the data series' is "0".


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Sandman

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #506 on: January 05, 2012, 06:43:03 PM »

The juxtaposition of the two data series shows a common point in time where both trends change. Based on the sparseness of the information presented I can't say that is significant or if it's coincidence, but it certainly catches my eye. I think it is an interesting phenomena and so far, I've run across nothing that indicates the events are unrelated or that would suggest the correlation of the data series' is "0".

Is there another data series that we could juxtapose that might offer a true (negative) correlation?  How about the meteoric expansion of production at salmon farms in the 1990s, which (despite a freeze on new tenures) grew from 15,500 tonnes in 1990 to 68,800 tonnes in 2001?   Hmm...as salmon farm production increases in the 1990s, Sockeye returns are decreasing?  Now THAT is a correlation (still does not prove causation perhaps, but a lot more "interesting" to my eyes).
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aquapaloosa

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #507 on: January 05, 2012, 08:57:57 PM »

Quote
http://alaskasalmonranching.files.wordpress.com/2010/08/alaskareleasecomparison1.jpg

I think the chart above could be viewed a little differently to better establish a relationship between the two quantities.  The Fraser river sockeye return line (red) should be moved back 3 or 4 years to better represent the time those two groups were in the ocean together at the same age perhaps competing or interacting on the same level.  Seems to me that Alaskan fry released in 1993 would have nothing to do directly with sockeye returns to the fraser the same year.  Those 1993 returned socks were out in the ocean with the 1989 Alaska fry.



« Last Edit: January 05, 2012, 08:59:52 PM by aquapaloosa »
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #508 on: January 05, 2012, 09:27:52 PM »

Is there another data series that we could juxtapose that might offer a true (negative) correlation?  How about the meteoric expansion of production at salmon farms in the 1990s, which (despite a freeze on new tenures) grew from 15,500 tonnes in 1990 to 68,800 tonnes in 2001?   Hmm...as salmon farm production increases in the 1990s, Sockeye returns are decreasing?  Now THAT is a correlation (still does not prove causation perhaps, but a lot more "interesting" to my eyes).

Indeed, the more data series that are considered, the more complete the picture becomes until eventually, some real understanding is achieved. The errors arise when one decides that some particular correlation is sufficient to provide that understanding and stops considering other inputs.
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shuswapsteve

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #509 on: January 05, 2012, 11:16:19 PM »

It would be great if we could all accept your word that antibiotic use is quite low, as you seem to be an honest person.....  :D  

It's a known fact that although the salmon farming industry collects disease and antibiotic usage data, not all farms comply with submitting their data (the requirements seem to be voluntary) and the ones that do, likely pick and choose which data they want to send in. When you have a voluntary reporting system like this the data can't be relied on! I suggest that they have little incentive to be honest with their reports as it would affect the marketability of their product.

I realize that DFO audits some of the farms on a random basis, however with the limited resources they have (and less next year) they are auditing a very small percentage of the farms. DFO reports that the antibiotic use is low are just opinions, and probably the equivalent of false advertising for the industry.

Can you provide evidence of accurate reporting by the industry? I need more than just your personal experience on a few farms.


Once again you are confusing your own interpretations as reality, but I have come to expect this from you.  In the website you provide as proof of your argument you concluded that “not all farms comply with submitting their data”.  This seems to imply that some farms wilfully will not participate which is not necessarily true nor is it outlined in the website you attached (but you probably knew that already…right?).  Why don’t you stick to what was actually said instead of exaggerating?  The next beauty comment is “…and the ones that do, likely pick and choose which data they want to send in”.  Really?  How do you know?  Again, you are assuming that fish farmers are being manipulative and dishonest in this regard.

When the Province was in charge they chose a sampling regime which focused most of the effort where there were active farms (called weighting).  This type of sampling is not that uncommon because it focuses your resources (which can be limiting) where most of the fish are – not where they are not.  Sampling does not necessarily mean that you get to every place all the time with maximum effort.  That’s why they call it “sampling”.  Secondly, you also have to know the difference between active and non active farms.  Not all farms are active at the same time, so they are not all going to be visited for audits.  Thirdly,  sometimes farm audits are cancelled due to adverse weather, or overriding health issues such as plankton blooms, low marine oxygen or other unforeseen circumstances.  When this happens the Province (when they were in charge) would try to reschedule the audit in the same quarter.  If you cannot do the audit for these reasons that are beyond your control this could cause variation in the calculations and results provided.  Again, you quotation from your source does not explain any other reasons for this variation.

The only thing I can see somewhat eye-to-eye with you is that budget cuts to the federal public service could affect the enforcing of the new regulations.  That is not the problem with the regulations, staff or DFO – it is with the people holding the purse strings in Ottawa.
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