New Paper on Effects of Cyanide on Corals

[MaryHM]

Changes in zooxanthellae density,morphology,and mitotic index
in hermatypic corals and anemones exposed to cyanide
J.M.Cervino ,R.L.Hayes, M.Honovich, T.J.Goreau, S.Jones, P.J.Rubec

This paper can be found in the Marine Pollution Bulletin 46 (2003) pp. 573-586

I realize that most of you don't receive a subscription to this fine publication along with your "People" and "Playboy", but if you can get ahold of a copy it's worth the read.

I'm not allowed to post the paper, but with Peter's permission I'll post the results- species tested, number of colonies per species tested, and number of deaths. Let's put it this way, I think we've found a new cure for Aiptasia- just dose them with cyanide!! :lol:

 

[Anonymous]

LOL just purchasing that article online would be worth more than a couple years of Playboy =)

not that I subscribe to that filth :roll: :wink:

Here's the full abstract:

Sodium cyanide (NaCN) is widely used for the capture of reef fish throughout Southeast Asia and causes extensive fish mortality, but the effect of NaCN on reef corals remains debated. To document the impact of cyanide exposure on corals, the species Acropora millepora, Goniopora sp., Favites abdita, Trachyphyllia geoffrio, Plerogyra sp., Heliofungia actinformis, Euphyllia divisa, and Scarophyton sp., and the sea anemone Aiptasia pallida were exposed to varying concentrations of cyanide for varying time periods. Corals were exposed to 50, 100, 300, and 600 mg/l of cyanide ion (CN-) for 1–2 min (in seawater, the CN- forms hydrocyanic acid). These concentrations are much lower than those reportedly used by fish collectors. Exposed corals and anemones immediately retracted their tentacles and mesenterial filaments, and discharged copious amounts of mucus containing zooxanthellae. Gel electrophoreses techniques found changes in protein expression in both zooxanthellae and host tissue. Corals and anemones exposed to cyanide showed an immediate increase in mitotic cell division of their zooxenthellae, and a decrease in zooxanthellae density. In contrast, zooxanthellae cell division and density remained constant in controls. Histopathological changes included gastrodermal disruption, mesogleal degradation, and increased mucus in coral tissues. Zooxanthellae showed pigment loss, swelling, and deformation. Mortality occurred at all exposure levels. Exposed specimens experienced an increase in the ratio of gram-negative to gram-positive bacteria on the coral surface. The results demonstrate that exposure cyanide causes mortality to corals and anemones, even when applied at lower levels than that used by fish collectors. Even brief exposure to cyanide caused slow-acting and long-term damage to corals and their zooxanthellae.

 

[dizzy]

I guess the biggest question I have is: Would corals in the oceans be exposed to cyanide for 1-2 minutes, or would the currents and water volume dilute and wash away the cyanide after only a few seconds?

 

[Anonymous]

Too hard to tell from the abstract - however it's only logical to try to duplicate what is seen in a collection area i.e. similar current rates and dilution.

However since they used weaker solutions and still saw significant damage - the study is still interesting.

 

[dizzy]

Tom,
It could be that when the coral is discharging mucus it is also ridding itself of the cyanide in short term exposure situations. It is possible this technique might only work for a brief period until the mucus reserves run dry, which would mean longer exposure to lesser amounts could be more damaging. Anyway it was just a thought and for the record I believe cyanide does damage corals, although maybe not in every single exposure event. I think they should test it on aquacultured frags in the ocean.

 

[Kalkbreath]

I can pee in the test tank and end up with the same results, Do the test in the ocean, in the current ,out on the reef or it meaningless. The same test with copper would also kill the corals in the control tank.............................. .yet would have little effect out on the reef....................

 

[Kalkbreath]

I also would like to point out that , Having some fish in the tank ,would be nice .........not for the fish ,,,,,but this would add to the credibility ..

 

[MaryHM]

How in the world would having fish in the tank add credibility to the study. They weren't studying cyanide effects on fish.

 

[PeterIMA]

While, we can not post the Cervino paper (copyrite laws), if anyone wants a digital (PDF) copy send me an email. It may be possible to download it off the Marine Pollution Bulletin website. We are looking into this.

Peter Rubec

Email [email protected]

 

[mkirda]

I also would like to point out that , Having some fish in the tank ,would be nice .........not for the fish ,,,,,but this would add to the credibility ..

Can you expand on this line of reasoning, Kalkbreath?

Regards.
Mike Kirda

 

[mkirda]

I guess the biggest question I have is: Would corals in the oceans be exposed to cyanide for 1-2 minutes, or would the currents and water volume dilute and wash away the cyanide after only a few seconds?

Mitch,

It would be different on every single application of cyanide from every single squirt bottle. It would depend on the concentration of cyanide in the bottle, on the coral morphology, on the water flow in and around the coral, even on how the fish kicks it's tail...

The point is though that, after application, you can still see the coral bleach if you visit the site the next day. Normally followed by death if visited on subsequent days... There is no doubt that cyanide does major damage to corals.

The experiment will try to minimize the differences above by using more dilute cyanide levels than what would normally come out of the bottle. In addition, it mimics fairly calm seas (normal for collection activities) by using dilute solutions for short periods of time, i.e. 1-2 minutes.

Now, you could argue that the time is too long, that corals should be held for shorter periods, i.e. 10 seconds or 30 seconds.
I wouldn't argue with you- would like to see that data myself.
I wonder if it may then turn out to be sublethal.

I invite Peter to comment.

Regards.
Mike Kirda

 

[PeterIMA]

I believe several people have questioned whether the experiments done in the laboratory by Cervino et al. mimic the actual cyanide plume dynamis that occur in the field. In my opinion they are similar to field conditions. James Cervino visited both Papua New Guinea and the Philippines and did some field experiments that are not part of the published paper (Figure 1 in the paper shows a cyanide plume created by a collector with a squirt bottle). He also interviewed collector who showed him corals that had been exposed to one squirt of cyanide. I have a number of these photographs where one can see white patches or white streaks across various species of Acropora. So, as Mike Kirda said there is no doubt that the cyanide is harmful to the coral in the field. I should note that I interviewed collectors in the Philippines in 1986 (The Effect of Sodium Cyanide on Marine Fish and Coral Reefs in the Philippines-Proceedings of the First Asian Fisheries Forum), who also told me the same things (cyanide kills the corals).

As far as plume dynamics are concerned, it is to be expected that the cyanide concentration will stay high near the center of the plume for at least 2-3 minutes in areas without strong currents. I know this from my own research with chemical plumes (my Ph.D. research studied responses by catfish to conspecific odours in an electronic monitoring tank at Texas A&M).

If you read the paper, you will see that James actually dosed corals with concentrations varying from 50 to 600 mg/liter (ppm) over various experiments. It is true to state that the adverse affects were not as pronounced at 50 ppm in comparison to 600 ppm. When the corals did not die in the short-term, Cervino documented a number of adverse affects including a) impairment of the rate of cell division (mitosis), b) expulsion of zooxanthellae (symbiotic algae needed for coral nutrition), c) inhibition of protein synthesis (shown with gel electrophoresis). The most severe situation was when corals shed their tunics (mantle tissue) leaving bare skeletons. The paper shows three genera of corals before and after. Actually, the research was conducted on 8 genera of corals and one sea anemone. In all cases, adverse affects were documented (although not every test animal died over the three month study period).

At the coral reef symposium in Bali, I discussed research on cyanide effects with corals conducted by Dr. Oakley in Malaysia (in the field). He put glass jars over the corals exposed to 1 ppm hydrogen cyanide (HCN). He told me that even at this low concentration the cyanide was harmfull to the corals. So far, I have not seen these results published (he may have done so, but I have not seen it).

My conclusion is that results may vary depending on the environmental conditions, initial exposure concentrations, exposure duration etc. But, in all cases the effects of exposing corals to cyanide are detrimental. Cyanide fishing needs to be stopped. NOW.

Peter Rubec

 

[mkirda]

Thanks, Peter.

 

[Kalkbreath]

Geee, what would fish add to the test? The vast majority of the time a HOBBY collector fishes with juice............... the collector uses an amount so small that the fish survive and are collected alive ...........then the fish are so healthy that they survive days at the exporters holding tanks .and then a forty hour plane ride to boot...........If you want to come even close to duplicating the real world.....a scientist must find the concentration in which the fish survive the cyanide exposure [like in the wild} This crap about how most of the time the fish die on the reef when cyanide fishing is silly..................you REALLY think a collector is going to kill three out of five Blue face angles by over juicing? The vast majority of cyanide fishing for this hobby {what little exists} is done in a manor that does not harm the fish {at least for the first week} So the test must be done with the results being that the fish are not out right killed and the corals are...........even then the effects residual cyanide on the denitrifying bacteria in the tanks and size of the system would make any indoor test results suspect {How bout a swimming pool size tank ?}{any one want to ask mr.4000?}

 

[wade1]

Geee, what would fish add to the test? The vast majority of the time a HOBBY collector fishes with juice............... the collector uses an amount so small that the fish survive and are collected alive ...........

Actually, I have to agree that using fish in the study (I downloaded and read the paper) would have added little. That was not the question beind addressed and would make for poor science (not to mention it wouldn't be published unless fully tested as a separate topic). We all know cyanide is bad for all living tissues, but this goes one step further in showing the true detriment directly to corals.

Wade

 

[dizzy]

As far as plume dynamics are concerned, it is to be expected that the cyanide concentration will stay high near the center of the plume for at least 2-3 minutes in areas without strong currents. I know this from my own research with chemical plumes (my Ph.D. research studied responses by catfish to conspecific odours in an electronic monitoring tank at Texas A&M). Peter Rubec

Peter,
While it may well be true that cyanide concentrations will stay strong inside the plume for 2-3 minutes, that does not mean the plume has not moved off the coral. IMO even the very slightest current would move the plume off the coral in a matter of seconds. It would take either dead calm or very large plumes for for the concentration to remain high in the exact same spot for very long. Just how big is the average plume? I work with slow revolving aquariums and I often watch as the food gets swept in the direction the tank is turning. It doesn't take much velocity when the entire body of water is moving. Does the ocean ever get dead calm? I don't remember ever diving when there wasn't at least some current.

I agree with you that cyanide fishing is very bad and needs to end immediately. I just think testing in the ocean would be more conclusive.

 

[PeterIMA]

Dizzy, As I previously stated studies have been done in the ocean. In addition to the work by James Cervino, David Oakley, Dr. Ross Jones in Australia came up with a technique whereby cyanide exposure to corals in the field can be verified using PAM flourometry. (I need to consult the paper to remind myself what PAM stands for). There are now over 5 scientific papers concerning the effects of cyanide on corals in peer reviewed journals.


I should mention that IMA supported the research with a contract to James Cervino for $10,000. Mr. Cervino is interested in obtaining more funding to conduct field studies on the effects of cyanide on corals. At the moment, the IMA does not have sufficient funds to support this. Why not create a fund whereby the trade and/or hobby helps fund the research?

Peter Rubec

 

[dizzy]

Peter,
If the currents weren't sweeping the cyanide away, why does Dr. Oakley use the glass jars? You may be right the experiments may perfectly replicate the natural conditions. I agree with you that cyanide is bad. I just like good research experiments.

 

[Anonymous]

Geee, what would fish add to the test? The vast majority of the time a HOBBY collector fishes with juice............... the collector uses an amount so small that the fish survive and are collected alive

The coral issues however are when the colector is trying to flush an ornamental out from a coral head or a hole near a coral head. Thus the chemical plume is going to contact the coral and move across the reef causing damage - not out in open water just away from the corals.

 

[MaryHM]

You may be right the experiments may perfectly replicate the natural conditions. I agree with you that cyanide is bad. I just like good research experiments.

This is not a bad research experiment. It's a necessary step. Say I'm going to do research on treating a human disease. The research is conducted in lab animals first. Is this the primary goal, curing a disease in a rat? No. It's just one step toward accomplishing that goal. There are obvious differences between rats and humans that will affect the outcome of the experiment. However, one can use the findings made by experimenting on rats to go to the next level- getting some groundwork laid for more important experiments down the road.