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mkirda

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John_Brandt":2n27o551 said:
Why would you seek to limit the number of alternative hypotheses?

That a CDT test is non-functional or unreliable must always remain as alternative hypotheses. That there may be inconsistencies as to how a CDT is applied must also remain.

I don't seek them, they just jump out at me.

Ok, I now see three possibilities. Well, four now...

1) CDT is correct.
2) CDT is inaccurate.
3) Accuracy of CDT depends on how it is done.
4) Accuracy of CDT depends on how much money is handed to the lab technician doing the test.

To me, #3 is just #2 put in a different light. And #4 is going to be a problem as long as there is corruptable human nature involved, but it still does not take away from the actual real result...

Am I missing any, really, when I limit it to it either works or it doesn't?

What does MAC have to do with any of this?

I've asked you the point of this thread a few times, which you have chosen not to respond to. This is unfortunate, John. At first, it seemed that you used an unfortunate title for the thread, one which by its very provocativeness implied an attack. Yet the post seemed to seek clarification, so I left it alone. Knowing that Peter was instrumental in bringing the CDT to BFAR to begin with, and knowing the history behind MAC's dismissal of the test, and your affiliation with MAC, the question gets painted in a completely different light though, John. You must always be aware of this. People will always, and I mean ALWAYS, think this way.

Do you disagree with Peter's numbers? Do you think that they are too high? Do you have anything to base your opinion on?

These are the questions that come to my mind.

Let me also make something clear here:
I think the numbers Peter has given are probably too high to be an average. I have always understood them to be upper estimates when applied across the board, especially given the known variability in physiological responses to cyanide exposure and the differences in species composition in various areas of the Philippines.

The hallmarks of scientific methodology are reproducibility of results, falsifiability, ability to withstand alternative hypotheses (most importantly being the null hypothesis) and "fitting in" with other generally accepted theories.

All fine and dandy, agree 100%. But the numbers listed here were always understood to be incomplete upper estimates, not based on extensive laboratory testing, were they not? I don't have some of the early papers (80's), but no where did Peter ever claim that such testing had been done... These have always been estimates based on observations and field communications. The fact is that such work would not pass such rigorous testing by scientific methodology as outlined...

Come to think of it, why would you think it could/would/should? At this point you just have me curious.

Regards.
Mike Kirda
 
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mkirda":35c0luf6 said:
If this is true, why would MAC support a CDT that doesn't work?

I really don't think that this thread has a direction. It just sort of meanders from asking why Peter's numbers have changed over time, to insinuating that the MAC-supported CDT doesn't work. What gives?
Is there a point to this? Forgive me if I don't see the connection.

Mike,

This thread has a very obvious direction: the discussion of the accuarcy of published mortality statistics and their applicability to the marine ornamental trade today. This has a huge impact in determining the level of impact the ornamental trade has on the reefs.

Mike, as far as I see the only people that are trying to turn this into a MAC thread are the typical cadre of MAC-bashers. Mike, what makes you think MAC is considering the IMA CDT via Ion-Selective-Electrode (ISE) as their CDT? Everything I've seen regarding MAC and their CDT would lead me to believe that they have never been completely satisfied the ISE and that MAC is investigating other analytical techniques. Thus MAC's delay in accepting a CDT.

mkirda":35c0luf6 said:
The only other plausible alternative hypothesis is that the CDT doesn't work.

Well, if the analytical data does not logically make sense that certainly is a plausability. One could also hypothesize a number of other things, such as possible exposure to cyanide from activities other than collection, for instance.

-Lee
 

mkirda

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John_Brandt":cgus0ik8 said:
Scott Meyerscough you have proven to be not worth a nanosecond of my time or attention (though that sentence took more than that) :wink:

John,

You are digging yourself a hole here, my friend... He was just being far more succinct than I was.

Regards.
Mike Kirda
 
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Back to the subject. How realistic are the numbers today? How realistic were they when they were published?
 

PeterIMA

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I think Ferdinand meant he had witnessed mortalities as high as 80% in exporters' facilities. It probably is not an average figure. It would be hard to make a profit if the mortality was 80% most of the time (on the average).

Response to Lee,

I would assume that the mortality figures in the trade represent both fish caught with cyanide and those caught by other means. A controlled experiment by Hall and Bellwood (1995) found that when groups of damselfish (Pomacentrus coelestris) were exposed to a concentration of 10 mg/L (ppm) cyanide ion for 85 seconds that 37.5% died (delayed mortality) over a 13 day experimental period (cyanide-alone condition) after being placed in holding tanks with clean water. With fish exposed to a stressor (coral rubble removed from holding tank) 25% died over the 13 days (stess-alone condition). With fish exposed to starvation (not fed) none died during the experimental period. The combined effect of all three factors led to 41.7% mortality.

Hanawa et al. (1998) exposed humbug damselfish (Dascyllus aruanus) to various concentrations of CN ion (25 ppm and 50 ppm) for different time intervals (10 seconds, 60 seconds, and 120 seconds) and then observed the mortality over 96 hours (four days). With the lower two concentrations and short durations (10s, 60s) no mortality was observed. With concentration of 25 ppm and a 120s exposure the mortality over 4 days was 60%. With a 50 ppm exposure for 120s the mortality was 100%. Of interest was that fish exposed to 50 ppm for 60s and then stressed (by being put into a plastic bag) 100% died during 96 hours.

The experiments demonstrated that a 2 minute pulse exposure to CN ion (25 and 50 ppm) was lethal for most test fish. With fish exposed to 50 ppm for 60 seconds and stressed by being bagged there was 100% mortality.

There was much higher mortality if the fish were exposed to cyanide and stressed in a manner similar to that used during transport/shipping. The addition of a stress immediately on recovery (after being removed from the cyanide and placed in clean water) by being placed in a plastic bag for 10 minutes to mimic conditions during transport killed all the fish. Hence, fish exposed to cyanide at concentrations and durations approaching "the lethality threshold" are extremely sensitive to post-capture stress. This could in part explain the low survival success observed in fish suspected to have ben captured with the aid of cyanide.

It should be noted that the concentrations used by Hall and Bellwood (1995) and Hanawa et al. (1998) are well below the levels used by the collectors in their squirt bottles (greater than 1500 ppm) Rubec et al. (2001). These scientific experiments confirm that delayed mortalities do occur with exposure to cyanide-alone, and that cyanide plus shipping stressors (like being chased wth a net, or put into a bag) contribute to higher rates of mortality.

Peter Rubec

References

Hall, K.C. and D.R. Bellwood. 1998. Histological effects of cyanide,stress, and starvation on the intestinal mucosa of Pomacentrus coelestis, a marine aquarium fish species. Journal of Fish Biology 47: 438-454.

Hanawa, M, L. Harris, M. Graham, A.P. Farrell, and L.I. Bendall-Young. 1998. Effects of cyanide exposure on Dascyllus aruanus, a tropial marine fish species: lethality, anaesthesia, and physiological effects. Aquarium Sciences and Conservation 2: 21-34.

Rubec, P.J., F. Cruz, V. Pratt, M. Oellers, B. McCullough, and F. Lallo. 2001. Cyanide-free net-caught fish for the marine aquarium trade. Aquarium Sciences and Conservation 3: 37-51.
 
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If species that really are not typically caught via cyanide keep showing up test positive, is there: 1) cross contamination from fish to fish in the holding tank, 2) secondardy cross contamination of samples, 3) adequate QA/QC of the analysis, 4) inadequate cleaning of lab equipment between analytical runs, 5) possible sources for exposure of animals to cyanide other than collection (eg. via mining operations), 6) possible exposure to cyanide via food fishing operations, 7) cross contamination of fish via residual cyanide on hand nets?
 

mkirda

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SciGuy2":393qci00 said:
Mike,

This thread has a very obvious direction: the discussion of the accuarcy of published mortality statistics and their applicability to the marine ornamental trade today. This has a huge impact in determining the level of impact the ornamental trade has on the reefs.

Mike, as far as I see the only people that are trying to turn this into a MAC thread are the typical cadre of MAC-bashers. Mike, what makes you think MAC is considering the IMA CDT via Ion-Selective-Electrode (ISE) as their CDT?

At the recent IMAC, David V. passed on the information that MAC would be using the IMA set-up, BFAR-run lab for their CDT, at least for the short term. So, what makes me think this? It was publicly stated by MAC...

Everything I've seen regarding MAC and their CDT would lead me to believe that they have never been completely satisfied the ISE and that MAC is investigating other analytical techniques. Thus MAC's delay in accepting a CDT.

MAC made the announcement back in May that it would be running in six weeks. The deadline came, then they said two more weeks, and that the delay was at BFAR's request. No one has bothered asking them yet what is up, even though that two week time window was surpassed maybe two weeks ago...

While MAC may have other rabbits up their sleeve wrt a newer CDT, my understanding is that research into other methods is on-going, but some efforts may be stalled for lack of funding. All of these methods are being worked on here in the US at different university laboratories. It remains to be seen how quickly a lab test could be commercialized, accepted by various testing agencies, and implemented in the Philippines. My guess is that this remains a longer term goal, to be implemented over a 2 to 5 year timeframe.

lee":393qci00 said:
mkirda":393qci00 said:
The only other plausible alternative hypothesis is that the CDT doesn't work.

Well, if the analytical data does not logically make sense that certainly is a plausability. One could also hypothesize a number of other things, such as possible exposure to cyanide from activities other than collection, for instance. -Lee

Unless the fish were caught down range from a mine tailings dump, cyanide exposure is exceedingly unlikely if not due to collection. I guess that the argument could be made that a non-cyanide caught fish kept in the same tank as a cyanide-caught one could possibly absorb some from the water. It would seem to me that this would be exceedingly easy to test for. Just try it, grind and test each. That ought to give you the results you need.

Regards.
Mike Kirda
 

dizzy

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mkirda":1pw5ejy2 said:
Mitch,
If you had been paying attention, you would also have read that a certain percentage of mandarins have tested positive for cyanide. Either you believe the results, or you believe that the test is flawed: There is no other option here.

Mike the other options here is that the exposure to the cyanide was coincidental and not intentional.

As for capturing clownfish, yes, I believe I could easily do it with my bare hands. Might get slightly stung, but they are not difficult to capture when inside an anemone. Certainly a net would be easier still, but in absence of a net, hands should work nicely...

Here I would reply that not all clownfish and all anemones are created equal. While you might be able to take a common clown by hand an A polymnus would likely be a far different feat. I can't hardly even catch them with a net in a 20-gallon tank.

As for the numbers, yes, they are mindboggling.
Go out into the islands sometime: You will find that they are not so mindboggling crazy afterwards. Realize that these are upward estimates, not givens on each and every shipment.

The numbers I am more familar with are the ones after the fish have been purchased. The collectors have the luxury of cheap replacements. The stateside numbers seem wrong to me. I hope the field numbers are off on the high side as well.

[Regards.
Mike Kirda

my 2cents
 

PeterIMA

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Lee, Are those questions? I sent you IMA's rebuttal to all those concerns voiced in an unpublished review by the MAC of the CDT methodology. The answer to all the questions is NO! I am willing to provide the documentation to reasonable people (it looks like Lee works for the MAC).

Peter Rubec
 

PeterIMA

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Lee, Are those questions? I sent you IMA's rebuttal to all those concerns voiced in an unpublished review by the MAC of the CDT methodology. The answer to all the questions is NO! I am willing to provide the documentation to reasonable people (it looks like Lee works for the MAC).

Peter Rubec
 

clarionreef

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LEE,
"CROSS CONTAMINATION VIA RESIDUAL CYANIDE ON HANDNETS?
Did you really say that? ["Thats a good one.]
Steve
PS. Dang, lost another humu-humu! Must've been more of that handnet cyanide residue contamination!
 

mkirda

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SciGuy2":2ilr99pc said:
If species that really are not typically caught via cyanide keep showing up test positive, is there: 1) cross contamination from fish to fish in the holding tank, 2) secondardy cross contamination of samples, 3) adequate QA/QC of the analysis, 4) inadequate cleaning of lab equipment between analytical runs, 5) possible sources for exposure of animals to cyanide other than collection (eg. via mining operations), 6) possible exposure to cyanide via food fishing operations, 7) cross contamination of fish via residual cyanide on hand nets?

Ok, there are two categories here:

1) Lab tech error.
2) Cross-contamination.

I think all of the cross-contamination options could be tested in a lab fairly easily. The only way to test for lab tech error is to introduce specimens that are known cyanide caught vs. cyanide-free, then see how the results come up...

Regards.
Mike Kirda
 
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Peter,

Thank you for your reply. Thanks to you I have been able to read some of the primary source information that you have listed. So I have seen many of the numbers you have just provided.

The question that I should have asked: is it safe to use the Hall and Bellwood (1995) laboratory data in conjunction with the reported mortality data gained by IMA survey?

For instance is the 50%, 30%, 30%, 30%, 30%, 30% = 91.6% total collection to retail mortality rate high due to statistical double-counting (as it were)? Conversly, should we conclude that Hall and Bellwood's (1995) observed mortality rate of 41.7% for stressed, cyanide exposed, and unfed fish be assumed to be the cumulative expected average mortality rate from collection to retail rather than the 91.6%?

Not wishing to provoke a fight, just discussion. Thank you for publishing much of the data that currently exists on this topic.

-Lee
 

PeterIMA

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John Brandt claims that my work was not peer reviewed. My paper Cyanide-Free Net-Caught fish was peer reviewed by Dr. George Dixon Head of the Department of Biology at the University of Waterloo. He also reviewed the flawed review by the MAC of the CDT Standard Operating Procedure (SOP) and concluded that Paul Holthus was wrong in the faulty conclusions reached (similar to Lee's false accusations). The studies by Hall and Bellwood 1995) and Hanawa et al. (1998) also were in peer reviewed scientific journals.

Finally, John go back to school and learn how to calculate mortalities. If 1000 fish are exposed to cyanide and 500 die that leaves 500 fish. Take 30% of 500, then take 30% of the remainder again. Don't use fish that died previously in your subsequent calcuations of cumulative total mortality.

Peter Rubec
 
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mkirda":22imig3s said:
Ok, there are two categories here:

1) Lab tech error.
2) Cross-contamination.

Mike:

There are many other things to consider beyond the two categories.

And yes, surrogate samples, duplicate blind samples, spike samples, and blank samples, etc. all play a part in a comprehensive QA/QC program.

-Lee
 

clarionreef

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Guys,
If it helps. I'm certain the cyanide positive on mandarins is explained by one of the anomalies offered. I worked with collectors of these for a few months and these guys were juicers. They complained about the difficulties involved with mandarins on account of impossibility of getting them with cyanide.
1st] The mandarins live deep into and under the interstices of coral branches and even if you could knock em out, you can't get to em without crowbarring all that coral out of the way.
and 2nd] They are cyanide proof and clam up and tough it out when assaulted with cyanide! From my interviews with a number of divers I found this to be a general consensus.
so...
The tradition is among all the mandarin collectors to spear them in the pectoral fin and pull them back out thru the coral braches. Sometimes they wiggle off and often they dont. As this became a superior method and more productive, the method spread and for decades has been the only method employed.
No mandarins are juiced and therefore all are 'netcaught' anyway. So...the CDT of this particular fish can be regarded with reference to this.
Steve

PS. Of course they have other negatives ie. the need for the myriad of worms and organisms found on fresh live rock [or one per large reef tank] to do well.
 

PeterIMA

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Lee, The answer is that the experiment by Hall and Bellwood only looks at mortality over 13days. Fish died from each factor alon and more fish died when the fish were exposed to cyanide, stress and starvation at the same time (not uncommon in the real world). So, if you capture fish with cyanide, and hold them on shore in plastic bags, and leave them out in the sun one can expect all of the above at the village level (where I conservatively estimated a 30% mortality in comparison to 41.7% mortality in the experiment by Hall and Bellwood (factors combined mortality). Now put the fish into a basket and put them on a bus at 5 AM and drive from Bolinao to Manila (about 5 hour trip), get off the bus and get on another local bus to go to an export facility, dump the fish in a bin and wait while the screener screws you by discarding the net-caught fish because they have scratches (don't worrry the screeners eat the fish that die anyway even those caught with cyanide). Now the exporter packs each fish individual bags (like clowns in a teaspoon of water) and ships them to Los Angeles. But, before they are put on the plane (about 5 hours after they were packed) they are left on the tarmac to cook. Then they take a 20 hour trip on the plane and if they are lucky they clear customs and make it to an importer's facility. If they belong to a transhipper who does not have a facility in LA, they clear the broker and customs go onto another plane to New York (total time from original packing to retailer in New York 45-50 hours). Now, some idiot who does not understand the problems of ammonia toxicity opens the bags and leaves the fish in the same shipping water. The fish die (within about 20 minutes) when the pH rises and the ammonium is converted back into toxic ammonia. Need I go on?

Peter Rubec
 

PeterIMA

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Lee, The answer is that the experiment by Hall and Bellwood only looks at mortality over 13days. Stress is cumulative. So the fish that did not die at each step of the chain can be further stressed and die later. So, I stick to my cumulative mortality estimates. It is much higher than 41%.

Peter Rubec
 
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PeterIMA":w3qppowc said:
Lee, Are those questions? I sent you IMA's rebuttal to all those concerns voiced in an unpublished review by the MAC of the CDT methodology. The answer to all the questions is NO! I am willing to provide the documentation to reasonable people (it looks like Lee works for the MAC).

Peter Rubec

No, those weren't questions aimed at you. I listed those points only for discussion of how a species that reasonably would not be collected via cyanide could test positive.

I'll reread the IMA's rebuttal you provided me with. I agree that the methodology was well defended by the IMA in the rebuttal.

But that aside, how would you interpret non-cyanide target species as analytically showing up with cyanide?

By the way, I'm not paid by MAC and cannot and will not defend everything they do.

Sincerely,
Lee

P.S. the "need I go on" comment was initially made to Mike Kirda. I retracted it.
 

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