A review and discussion on the research of Dr. Peter Rubec

[John_Brandt]

"The collectors get paid by the number of fish caught, and they can catch more fish per day using cyanide than using nets." Rubec 2001

"I (also) believe that an experienced net-collector can collect more individual fish and more species than the cyanide collector." Rubec 2003

"Aquarium fish collectors using cyanide use it on all species they encounter. While, it may be easy to capture clown fish with nets, they are often caught with cyanide because the collectors don't have nets, don't use nets, and use the same tool (a cyanide squirt bottle) on all the fish they wish to collect." Rubec 2003

 

[John_Brandt]

About 50% survive the initial exposure if rapidly moved to clean water. Rubec 1986, 1987

An estimated more than 80 percent of cyanide-collected aquarium fish die in the chain from collector to aquarium hobbyist. Rubec 1988

He (Rubec) estimates that at least 10 percent of cyanide-caught fish die at each step in the trade route. From Scientific American Magazine 2001

Total mortality through the chain (over 90%). Rubec 2001

Mortality at the retail level of marine fish was on average: 60% on the east coast, 35% in the mid-west, and 30% on the west coast of the USA, during the first three days after their arrival at the stores. Rubec 2001

 

[PeterIMA]

The quote from Sarah Simpson in Scientific American incorrectly stated the mortalit was 10% at each step of the chain. Actually, I estimated that the mortality on the reef was about 50% and 30% at each step of the chain from collector, exporter, importer, to the retailer.

Lets hear your whistles.

Dr. Peter Rubec

 

[John_Brandt]

Does the collector experience both a 50% (at the time of collection) and a 30% (before selling them to an exporter) mortality?

Or, do the steps go 50%, 30%, 30% and 30% ?

 

[PeterIMA]

OK, John lets hear what you have to say.

I should note that the quote from Scientific American incorrectly stated that the mortality was 10% on average at each step of the chain from reef to retailer. Actually, I estimated the morality on average was about 30% at each step of the chain (from collector, exporter, importer, wholesaler, retailer). Cited in Rubec 1986, 1987, and Rubec and Soundararajan 1991.

Peter Rubec

 

[John_Brandt]

OK, John lets hear what you have to say.

I should note that the quote from Scientific American incorrectly stated that the mortality was 10% on average at each step of the chain from reef to retailer. Actually, I estimated the morality on average was about 30% at each step of the chain (from collector, exporter, importer, wholesaler, retailer). Cited in Rubec 1986, 1987, and Rubec and Soundararajan 1991.

Peter Rubec

Peter, it's understandable that you were misquoted by Simpson. We can mentally toss out those 10% figures.

But what numbers are you settling on? 30-30-30-30% or 50-30-30-30% or what?

 

[PeterIMA]

Based on information previously published in aquarium magazines (cited in Rubec 1986) I estimated that the acute mortality on the reef was about 50%. The collectors then hold the fish and experience about 30% mortality prior to selling their fish to the middleman or exporter. Mortality was about 30% at each subsequent step of the chain. These estimates were based on the situation in the mid 1980s (when cyanide use in the Philippines is believed to have been more prevalent than now).

Peter Rubec

 

[John_Brandt]

Based on information previously published in aquarium magazines (cited in Rubec 1986) I estimated that the acute mortality on the reef was about 50%. The collectors then hold the fish and experience about 30% mortality prior to selling their fish to the middleman or exporter. Mortality was about 30% at each subsequent step of the chain. These estimates were based on the situation in the mid 1980s (when cyanide use in the Philippines is believed to have been more prevalent than now).

Peter Rubec

Using those estimates it looks like about 86% mortality from the moment of exposure to the retailer.

 

[John_Brandt]

Based on information previously published in aquarium magazines (cited in Rubec 1986) I estimated that the acute mortality on the reef was about 50%. The collectors then hold the fish and experience about 30% mortality prior to selling their fish to the middleman or exporter. Mortality was about 30% at each subsequent step of the chain. These estimates were based on the situation in the mid 1980s (when cyanide use in the Philippines is believed to have been more prevalent than now).

Peter Rubec

Using those estimates it looks like about 86% mortality from the moment of exposure to the retailer.

This means that for every 100 fish that a collector squirts only 14 will be swimming in retailer tanks.

This would still apply now, yes? I mean cyanide is just as lethal now as it was in the mid 1980's, yes?

 

[PeterIMA]

I estimated that the cumulative mortality was over 80% (excluding the mortality on the reef (Rubec 1986). The cumulative mortality was over 90% if one included the mortality on the reef and had five steps in the chain from reef to retailer. I recognize that there might not be a wholesaler (or a middleman). So cumulative mortality varies widely (just as the acutal mortalities at each step vary widely). My estimates for the mortality are rough averages at each step of the chain.

I can accept your cumulative mortality estimate of 86%. This is similar to my own. I would not accept an estimate of cumulative mortality of about 30% (Simpson in Scientific American) or one presented in National Geographic (about 50%) published several years ago. The writers of these articles did not present how their estimates were derived.

Peter Rubec

 

[John_Brandt]

OK, are you now revising your 2001 estimate of 60% mortality at East Coast retailers down to 30%?

 

[John_Brandt]

I estimated that the cumulative mortality was over 80% (excluding the mortality on the reef (Rubec 1986). The cumulative mortality was over 90% if one included the mortality on the reef and had five steps in the chain from reef to retailer.

Five steps from reef to retailer? Is that collector, middleman, exporter, importer, retailer?

 

[mkirda]

Wasn't this always an 'up to' estimate, Peter?
When we have spoken, I've always heard you talk about mortality rates of "up to X%"...

People should also understand here that there are no really great numbers on mortality. Not sure if this is due to the obviousness of it all (Duh, cyanide kills the fish, corals and the reef itself... Why bother figuring out the exact percentage?), lack of funding, or the severe side effects of trying to expose the cyanide trade. Most of the numbers I have seen have varied, and most have seemed to have been estimates based on some field work and some interviews.

For what it is worth, I do believe that Dr. Rubec is sincere in publishing the estimates, and that they are accurate as far as he can tell.

Can I ask what exactly is the point of this thread, John?
Do you think that these numbers are too high?

Regards.
Mike Kirda

 

[Smyerscough]

Can I ask what exactly is the point of this thread, John?
Do you think that these numbers are too high?

Regards.
Mike Kirda

What is the point of this thread other than to make a respected member of community look bad.

Is MAC questioning Dr. Peter Rubec's credibility ? If so WHY ?

Or is this just John Brandt MAC BOARD MEMBER trying to discredit him ?

I really must get off this train !

Scott

Owner Imagine Ocean[/b]

 

[PeterIMA]

John, In 1986 I estimated the mortality at 50% on the reef 30% at the collectors site (village), 30% at each subsequent step of the chain. I did not mention the retailer or the hobbyists that continue to experience mortality. Your question was whether if I calcuated 60% at the retail level on the east coast (in paper published in 2002) whether this should be 30%? Obviously, not since the 2002 paper and my previous postings here stated that Frank Lallo determined that the mortality at the retail level was 30% on the west coast of the USA, 35% in the midwest, and 60% on the east coast. This is just a refinement of the earlier estimates (which confirms that mortality at the retail level was "at least " 30%.

As John Tullock stated in his article (and I stated in the Cyanide-Net Caught paper) longer distances and more time in transport contributes to higher mortaliy. This is presumably due to inceased stress on the fish with the accumulation of ammonia in the shipping bags (the drop in pH may also be harmful). If you read my paper you would know I don't lay all the blame for the mortality on the use of cyanide. Shipping and handling practices need to be addressed as well. So, what is the MAC presently doing about this?

 

[PeterIMA]

Reply to Mike Kirda, I acknowledge that mortality rates vary widely at each step of the chain. For example, Don Dewey noted in 1979 that mortality in exporter facilities often varied from 15 to 75%. Ferdinand Cruz in email to me stated that the mortality in exporter's tanks was 80%. I have used 30% as a rough average of this variation at each step of the chain. It is of interest that for the past 20 years, no one in the trade has attempted to contradict this by providing other data or claimed that I was wrong.

Peter Rubec

 

[PeterIMA]

John, Yes, the five steps in the chain could be collector, middleman, exporter, importer, and wholesaler. One could eliminate one (either the middleman or the wholesaler), but still have five steps if one includes the retailer.

Basically, the fish die because they were caught with cyanide and then poorly handled (packed too tight in the shipping bags and shipped for to long a time period). Fish caught with cyanide experience higher rates of respiratory metabolism in the liver (Hanawa et al. 1998). So, there is experimental evidence to confirm that cyanide exposure detrimentaly affects the physiology of the fish, contributing to high delayed mortality. Please read my discussion of this in the Cyanide-Free Net-Caught paper I wrote posted on the Live Reef Fish Information Bulletin Vol. 7 or send me an email, and I will send you the scientific reprint from Aquarium Sciences and Conservation Vol. 3 (2002).


Peter Rubec
Email: [email protected]

 

[Anonymous]

Ferdinand Cruz in email to me stated that the mortality in exporter's tanks was 80%.

Peter,

Please explain this 80% number. It is new to me. Was Ferdinand saying that 80% mortality is typical in exporter's tanks? Was he saying that he has seen motality as high as 80% in their tanks?

Thanks,
Lee

 

[Anonymous]

Reply to Mike Kirda, I acknowledge that mortality rates vary widely at each step of the chain. For example, Don Dewey noted in 1979 that mortality in exporter facilities often varied from 15 to 75%. Ferdinand Cruz in email to me stated that the mortality in exporter's tanks was 80%. I have used 30% as a rough average of this variation at each step of the chain. It is of interest that for the past 20 years, no one in the trade has attempted to contradict this by providing other data or claimed that I was wrong.

Peter Rubec

All of these numbers are specific to fish collected via cyanide, correct?

It isn't possible that the exporter mortality rates are for a mixture of cyanide and non-cyanide collected fish?

 

[mkirda]

It isn't possible that the exporter mortality rates are for a mixture of cyanide and non-cyanide collected fish?

Yes, Lee, of course.

There are really two components here, that people are getting messed up...

1) Cyanide exposure
2) Handling

Net-caught fish can die of mishandling just as cyanide fish can. Actually, their mortality rates *should* be less because they are less stressed typically, but they can still die in high numbers if handled inappropriately.

I wish we had really good numbers, but they are not known. In talking with Ferdinand and Marivi and many of the collectors, one thing that became clear was that not all fish handle cyanide exposure in the same way. Some species suffer mortality rates of close to 100% right there on the reef when exposed to cyanide. Other species seem to tolerate it and survive on down the line, typically for months, before dying in hobbyist's tanks. Other species seem to take it in stride, with fairly high recovery rates. In other species, if they survive exposure, they seem to make a full recovery. (And no, I do not have a list of species in each of these categories...)

Taken collectively, and given a specific species composition in a given area, you can see how estimates of mortality can vary due to the varying level of effects. You also need to stop and think for a bit: Do we ascribe the cause of death to cyanide or poor handling? Or is it a combination? If someone chooses to eat the wrong food and smoke a lot, do you ascribe the cause of death to smoking or heart disease? Or both? Where to draw the line?

It kills me when I read about clownfish testing positive for cyanide exposure: There is absolutely no need for it! Even I, a city boy with limited diving experience and absolutely zero fish collection experience, could collect clownfish with my bare hands, no net required. My understanding of mandarin fish habitat and life history leads me to the same conclusion: There is no reason why they should be caught with cyanide either...

This is why education and net-training are so vitally important, IMO.
To make an analogy, this is like giving someone an axe, pointing them to an orchard and telling them to go get some fruit. Not knowing about a ladder, and only having an axe as a tool, the only way to get the fruit is to cut down the trees. It is a great way of getting the fruit. For one season. After that, no more fruit...

Regards.
Mike Kirda