Sabtu, 16 Februari 2008

The Tragedy of Artificially colored Live Corals


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Magenta “Colt” coral.
Fading yellow "Cup" coral.
Pink “Finger” coral.

The trade in reef animals for the aquarium hobby has seen a recent and abhorrent novelty manifested in the occurrence of artificially dyed corals. Normally pigmented octocorals (soft corals) and scleractinians (stony corals) have both been subjected to unnatural pigmentation in gaudy, unreal colors of pink, magenta and bright yellow, just to name a few. Most experienced aquarists recognize such animals as inherently unnatural (and inevitably compromised) and almost intuitively avoid purchasing them. Regrettably, however, enough uninformed aquarists continue to discover such wonders of incredulous color and fuel the trade and practice of dyed corals with their purchases. Some of the most commonly dyed corals include, but are not limited to: "Leather/Finger" coral (Sinularia), "Colt" coral (Klyxum), "Cup" coral (Turbinaria peltata), "Flowerpot" coral (Goniopora), and "Trumpet" coral (Caulastrea), as well as sebae and "carpet" anemones.

One could be tempted to say that responsibility for suffrage imposed upon dyed corals by this technique sits partly upon the shoulders of the dealers of marine livestock. Dealers could choose not to order such animals deliberately or pay for those sent as so-called "substitutes" to effectively tantalize a vendor and its customers. Part of responsible retail, in my opinion, does indeed include a conscientious decision by merchants to not make inappropriate animals available for impulse purchases by uninformed customers that are largely represented by impressionable new aquarists. These are the hobbyists least likely to be able to successfully care for diseased, stressed or dying animals. The argument would proffer the notion that a merchant should want to take the long-view of farming more satisfied and loyal customers for the trade with helpful sales and products to encourage the long-term participation and investment in the hobby by consumers. A responsible retailer should take heed of such matters out of sober consideration for the future of their very livelihood, if not with empathetic concern for (or moral obligation to) the living resource of the reef environment. It may not even be enough for a good dealer to simply avoid bad products when another merchant is willing to sell them; however, educating the consumer is in everyone's best interest. Some of the world's best aquarium products dealers guide their customers with detailed livestock husbandry placards, seminars and workshops, good book recommendations and, of course, honest and accurate advice. Indeed, successful aquarists are the lifeblood of a dealer's trade in the aquarium hobby, and every merchant should be intimately concerned with attracting and keeping customers when the rate of attrition (aquarists leaving the hobby) is unnecessarily high. Obviously, failing and disillusioned hobbyists are not inspired to continue spending money in the trade while watching stressed and dying animals in their aquariums. In plain language, however, the ultimate weapon for empathetic participants in the industry of aquarium science against dishonorable practices is truly, instead, the educated consumer.

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A pink “Finger Leather” (Sinularia).
A yellow branching “Colt”(Klyxum…also known as Cladiella or Alcyonium).
A magenta branching "Colt."

The Educated Consumer

Aquarists owe it to themselves, if not the reef denizens that they admire so well, to research prospective livestock and their captive needs with consideration for the care that they are willing or able to provide for said animals before making a purchase. Part of this process of discovery should reveal the history of a coral's fundamental viability in captivity. Let there be no doubt that educated consumers alone and single-handedly can make or break the trade in an animal. Regardless of how many dyed corals are "produced" by exporters or ordered by dealers, the consumer has the final word on the lifespan of any such product offered on the market. In a brief segue, let me offer a topical analogy for comparison. There has been concern in our society for the escalating portrayal of violence in popular cinema and what effect it might have on people and, more specifically, how it might shape the minds of our children. In any event, let there be no doubt that the creators of such movies would not continue to produce multi-million dollar films with extreme violence, for example, that failed to draw a single paying customer to the theater. Movie producers, quite like coral exporters and dealers, are not operating charities! Rest assured that they do not wish to ever offer a product that will not sell well, let alone incur a loss or debt. And so, the educated consumer need only vote with their feet by leaving the establishment selling inappropriate animals and not spending their money. This will promptly and directly impact what is offered in the market. On the contrary, a dyed coral purchased by an aquarist is a vote for the product and will likely be replaced by another in kind. With this article, I intend to introduce aquarists to the practice of dyed live corals. I hope to succeed in helping folks to identify and avoid artificial specimens, and to assist those with dyed specimens inadvertently in their charge.

Identifying the Problem

The notion of dying aquatic animals is hardly new even among cnidarians (stinging-celled animals). For many years, exporters have dyed anemones in a dreadful practice that unequivocally compounds shipping stress and rates of morbidity in such animals that have an already high rate of mortality. In the early years, the practice was applied in a myriad of colors before aquarists and dealers began to realize the dismal impact it had on the anemone's survivability. Alas, the practice has not been entirely eliminated, as the occurrence of dyed sebae and carpet anemones is still observed, albeit limited in scope and color. Artificially dyed yellow sebae anemones are perhaps far and away the most common perpetration of the act. Like carpet anemones (Stichodactyla sp.), sebae anemones are naturally brown or green colored and occasionally a very pale yellow cream color (but NO vivid yellow). And while uncommon color morphs may exist, they are rare and priced accordingly. More often, aquarists will find unusual colors in stressed, bleached or dyed animals. Stressed animals will appear to have a thin or watery visage as with yellow or lime colors in naturally green specimens and tan or crème colors in formerly brown pigmented animals. The most severely stressed anemones will appear to be white colored. Bright colored tips (often purple) will remain if they were natural originally, as they generally are not a zooxanthellate pigment or readily aborted under duress.

The paling change of color in stressed cnidarians (coral and anemones) approaching white is the expulsion of life-giving symbiotic algae (zooxanthellae) under stress. Without zooxanthellae to provide food/carbon through photosynthesis with adequate light, a "bleached" animal is resigned to starve to death in weeks or months without extraordinary diligence from an aquarist with compensatory feeding of particulate and/or dissolved foods to the dyed victim. The coral or anemone will continue to execute normal polyp cycles, at least in the early weeks after the assault, and this will make direct supplemental feeding easier. We should assume that a dyed coral or anemone would require the same due care and consideration as a pale stressed or bleached animal. The fundamental problem with dyed corals and anemones is likely that the saturation of their tissue with dye impedes the penetration of light into, and the refraction of light within, their cnidarian tissue for the proper stimulation of zooxanthellae in symbiosis. Even without definitive scientific proof to confirm this, our present understanding of the dynamics of zooxanthellae in symbiosis with a host cnidarian lends a very informed assumption of the deleterious possibilities of dying live coral tissue. Any shading or corruption in the illumination of these symbiotic algae as with dye-stained tissue surely impedes their function and ability to feed and support their host. The animal at this point would be stressed and must photoadapt, if even possible, like a shaded coral, with the hope that a compensatory source of carbon (organismal or absorptive feeding, for example) will carry it through until the dye fades and zooxanthellae recover or return.

Of course, the previous suggestion also assumes that dye causes no other harm than impediment to symbiotic algae and this may very well not be the case. The entire dilemma is underscored by the everyday reality seen by aquarists in dyed animals with increased stress of acclimation and subsequent mortality as depicted in the series of photos below. Such corals appear otherwise "normal" at first with full polyp expansion and cycles (below left). Soon, however, the natural and full extent of polyp cycles becomes diminished (below center) and the intensely dyed pigment begins to fade. The paling color soon reveals an animal that has also lost its natural pigmentation. What better proof, I say, against ignorant or unscrupulous dealers of dyed animals that this practice is harmful than the very absence of natural coloration (life supporting zooxanthellae) after the dye fades? Volumes have been written on the function of zooxanthellae and it is unmistakably clear what happens to a cnidarian that loses or expels its symbiotic algae: loss of vitality and increased rates of mortality. Without zooxanthellae, these animals suffer ever more each day and become more vulnerable to pests, predators and diseases, not to mention the consumption of their own tissue from starvation without their zooxanthellae. In severe cases, tissue necrosis begins to ravage the animal (below right) and death is imminent. Under the best circumstances (often with the otherwise durable Turbinaria peltata "Cup" coral), the animal will require months to recover resident zooxanthellae in a process of abnormal blotchy color that lends one to think that the animal is recovering poorly. Even when such animals survive, their rates of growth will have been significantly reduced and they may even have lost mass to consumption. Essentially, we might be able to equate the compromise between a bleached coral to a dyed coral by virtue of the apparently reduced translocation of carbon from like diminished populations or activities of zooxanthellae.

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Stressed, dyed Sinularia bleaching of pigmentation (dye and zooxanthellae).
The dye is gradually fading in this Sinularia.
Tell-tale signs of a severe necrotic infection on the blackened tips of this newly imported Sinularia.

How to Identify a Dyed Coral

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Photos: Turbinaria peltata at left, dyed yellow and center, blotchy dye - fading and recovering natural color, and at right, a natural color of the "Cup" coral. Natural colors include variations of solid or combined brown, gray, tan and green… but never such bright yellow. There are naturally occurring bright yellow Turbinaria in other species for which this animal may be mistaken. However, a cursory exam by even laymen can distinguish most every T. peltata from any other popular species in this genus by the presence of large sparse polyps on the corallum in contrast to the generally tiny polyps of other yellow Turbinaria.

Identifying a dyed coral can be a difficult obstacle for the novice aquarist, for whom the marvel of so many naturally wondrous colored corals has not yet afforded an eye to distinguish the few unnatural or corrupted specimens from the many innate naturally pigmented beauties. For all aquarists, the best weapon in defense of such unwise purchases is, again, being an informed, educated consumer. This entails conducting adequate research on an animal before and beyond the biased assurances of a dealer, however well intended that person may seem. A responsible aquarist will not indulge in impulse purchases of animals for which they know nothing. As empathetic admirers of the coral realm, we are obligated to research a coral's fundamental needs of husbandry such as light, feeding, water quality and especially viability (hardiness). Unfortunately, some unscrupulous dealers have been marketing dyed corals as super-colored or very rare specimens (often at a premium price: the ultimate insult to the consumer). Such tactics exploit the mesmerized and uninformed consumer's inclination to make the impulse purchase for fear of missing the chance to acquire something "special". If one could see these dyed corals on import, however, the "special" nature of their color would often be more apparent as their shipping water is often not-so-mysteriously the same color as their tissue. In some cases with scleractinians, the most conspicuous evidence that such animals are "manufactured" is the presence of exposed corallum (skeleton) that is stained the same color as the coral tissue! Let's be clear about this; scleractinian "skeletons" almost without exception are white calcium carbonate. The non-scleractinian but stony-like octocorals Tubipora and Heliopora do produce a red and blue "skeleton" respectively, but no corals produce bright canary yellow or neon pink "skeletons" naturally. Indeed, it cannot be stated any simpler or more emphatically: information is the oxygen of understanding.

Caring for Dyed Coral

For aquarists that find themselves in the service of a dyed coral for any reason, the single most important dynamic to remember for improving the animal's chance of survival is feeding. Beyond the essentials of good water quality for reef invertebrates, it is critical to feed dyed corals as well or better than natural corals to compensate for their loss of production from shaded or expelled zooxanthellae. Dyed corals are likely starving animals. Their immunity is weakened and they may very well be dying. How much to feed will depend on the coral species, of course. But take heed that most reef aquarists drastically underfeed their corals and too many others at large inappropriately feed their tanks (such as with heavy feedings of phytoplankton to zooplankton feeders).

Another significant consideration for aquarists in the charge of dyed corals is the effect of bright reef lighting systems on a new and stressed animal. Indeed, a dyed or bleached and recovering animal can be quite sensitive to excessive illumination, which can and does increase rates of mortality if misapplied. Under-illumination, however, can often be compensated for with appropriate feeding or perhaps most only with what appears to be inadequate light (more about this below). There has been a popular and abused trend in modern aquarium keeping towards, what is in my opinion, the obscenely intense illumination of shallow reef aquaria with unnecessarily high wattage metal halide lamp. While some corals tolerate or even need such lighting (favored by many SPS coral keepers), the overwhelming majority of popular corals can often suffer in shallow water under banks of 400-watt bulbs. In fact, prior to the application of "lava-making", high intensity lighting schemes, most every coral kept successfully in the last decade was maintained nowhere near its saturation point for photosynthesis. However, a coral does not need to be illuminated so closely near its saturation point to thrive, but rather can fare quite well simply meeting or slightly exceeding its compensation point. And with the reality of sensible lighting schemes and regular feedings, such coral not only maintain but also grow very well without being radiated by the most extreme end of the spectrum. And so, let me suggest that dyed and recovering bleached corals be kept in low to moderate light, likely in the bottom third of a well-lit aquarium. In time, and with evidence of recovery, the specimen can be slowly moved up the rockscape to brighter light and gain slowly improved natural pigmentation. For additional tips on acclimating stressed symbiotic animals, please refer to the chapter on lighting in my Book of Coral Propagation, Volume 1 or visit our Wet Web Media internet site where the revised excerpt is posted.

Responsible Aquariology...

In parting, what can you do to help? First and foremost, don't buy these animals! Vote with the strongest weapon you have… the consumer dollar. If the shippers that execute this abhorrent practice are too ignorant to know or care about a better way, and the local retailers are similarly ignorant or worse, then send a quiet and powerful message: don't spend your money on them. If you feel compelled or are in a position to be able to help a good dealer who would embrace a polite education on the practice, then by all means speak up and please do it respectfully. Perhaps share a copy of this article or any other bits of information that might seem topically helpful. Indeed, for every day there is a better way.

The single greatest threat to our industry and the hobby of aquarium science at large is not restrictive legislation on the importation, transportation and sale of exotic aquarium life: it is the attrition of participating aquarists! At times the number of new aquarists entering the hobby and then leaving prematurely soon seems like a great revolving door. If such aquarists could be better educated and advised to succeed, then the hobby at large would benefit tremendously, from the profits of the merchants through to the body of knowledge that we know collectively as aquarium science. For this we all need to do our parts with collectors delivering healthy and appropriate livestock, retailers providing honest and accurate service and aquarists promoting education and good fellowship.

Note: as an interesting and redeeming aside… The manager of one of the shops where some of these corals were photographed was given a copy of this article. He took it to his owner and they quite plainly agreed on the substance and merit of the matter. For various reasons, not the least of which was honest ignorance in the hectic schedule of the everyday workweek, the significance and reality of dyed coral had slipped by them. A regular customer of this shop and mutual friend of mine had politely proffered the article. As reasonable and intelligent retailers they simply recognized the problem and agreed to stop ordering or paying for shipped dyed animals. Although they have certainly helped themselves and their customers by choosing not to support such practices, I give them my thanks and admiration for making a decision that serves the greater good of the industry for all.


If you have any questions about this article, please visit my author forum on Reef Central.

From the upcoming second volume of the Book of Coral Propagation: REEF GARDENING FOR AQUARISTS, by Anthony Calfo 2002/2003.

A special thank you to Doug Brummet of the Bay Area Reef Enthusiasts club (B.A.R.E.) and Amy Larsan for their assistance in helping to secure useful photos for this article.

Photographs by Anthony Calfo and Tom Cook.

Questions for the author or regarding the Book of Coral Propagation, Volume 1 may be directed to: anthonycalfo@readingtrees.com.

Please look us up on the Web at: www.readingtrees.com.



From : http://reefkeeping.com/issues/2002-09/ac/feature/index.php

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