Input on Herbivorous Fishes

[Ret_Talbot]

Might as well mention a book called "Surgeonfishes Rabbitfishes and their relatives" by by Kuiter and Debelius. You might find some useful information in this book.

Sorry. I ceased getting e-mail alerting me to new posts on this thread. Glad I checked in. I am quite interested in this title but can't get a hold of it for under $100. I'm going to check the library. Thanks!

 

[Ret_Talbot]

I'm curious where you write for and where your previous articles are published?

As a freelance writer, I write for a wide variety of national and international print and online publications ranging from aquaria-related stuff to educational stuff. Much of my work writing in the marine aquarium industry is copy creation for aquaria-related websites, which I generally don't publish under my own name, but I will be able to share some links on several aquarium-related projects that are in the works very shortly if you're interested (and I'd love your feedback, of course).

 

[Ret_Talbot]

Better to protect Diadema urchins as opposed to vertebrate herbivores...In the Caribbean, loss of Diadema through disease and environmental problems is a much bigger problem than removing parrotfishes. The patch reefs off Belize are covered in thallose algae and still have huge numbers of parrots - few Diadema though.

Jay

p.s. - batfishes are omnivores with a strong tendency towards being carnivores.

Hey, Jay.

I've looked into the whole urchin thing pretty extensively in both my research and in my time in the water on Caribbean reefs. I agree that the massive die-off of urchins is a huge problem, and that's actually one of the reasons IMO to focus on herbivorous fishes.

The role of herbivorous fishes on degraded reefs that have experienced a phase shift away from coral-dominated toward algae-dominated habitats (often as a result--at least in part--of urchin mortality) is poorly understood based on my research. I'd probably agree with you on the parrotfishes front, except I'm quite interested in several ongoing research projects in the Caribbean that are looking specifically at the functional role/capacity of various species of parrotfishes on degraded reefs. Some of the interesting data coming out of these studies suggests that we need to learn a lot more about parrotfishes and their ecological function before saying that their numbers are stable.

For starters, a parrotfish is not a parrotfish is not a parrotfish. Different species appear to be better at consuming different kinds of algal growth. For example, the queen parrotfish seems to rule when it comes to macroalgae like that found on reefs that have already experienced a phase shift and now have established macroalgae populations. Further, adult parrotfishes are better grazers on macroalgae than juvs, and overfishing (for food) may well be a problem as fishermen tend to target the large parrotfishes.

Nonetheless, I think there is a great danger of putting too much emphasis on parrotfishes (and surgeonfishes, for that matter) in terms of their role as primary grazers on degraded tropical reefs. Other studeies in the Indo-Pacific have clearly shown that fishes such as some rabbitfish species are much better when it comes to eating established macroalgae. In other words, and this is sort of my take home point at present, the fishes needed to keep algae growth in check on degraded reefs are not the same fishes that may best help an algae-dominated, degraded reef recover.

This brings us to batfishes, which have been shown in recent studies to outcompete ALL indiginous, known herbivorous fishes on some Indo-Pacific reefs when it comes to eating established macroalgae. Whoa! When presented with data that supports conclusions such as that, we become painfully aware of how little we really understand these fishes and their role as either primary grazers on reefs or sleeping functional groups that may be critical to tropical reef recovery.

Does all that make sense? The difference between parrotfishes, surgeonfishes, rabbitfishes, and batfishes insofar as it pertains to the marine aquarium industry is that, generally speaking, parrotfishes have the highest captive mortality of the four groups. That fact, combined with ongoing research, makes the parrotfish the best candidate for a self-imposed ban in the industry IMO.

I welcome your thoughts.

 

[Fish_dave]

I find this discussion quite interesting. Please do not take anything that I say as negative or even challenging, I am just throwing out some ideas and observations that I have as food for thought.

First off are you suggesting that the trade make a self imposed ban on parrot fish to show those outside of the hobby that we care and can organize to action, or is the purpose to actually help the wild reefs in some way. Considering the effort that it will take to bring about a self imposed ban in this industry would it be better to target something that will have meaningful impact on the reef ? As an analogy to the personal computer recycling you brought up, if we have the power to change something would it be best to have all personal computers recycled (small improvement) or go for something that will really have an impact and have all electronic products recycled ? IF the aquarium trade could agree to a self imposed ban would it not be better to ban Yellow Tangs rather than the odd parrot fish that is brought in? Or ban Tangs altogether as a family ? I don't see the good of banning something of little impact. It would be an easier job to get the trade to self ban parrot fish than it would be for tangs as we really don't want or need the parrots already, but would it really make a difference to the reef or only make some folks feel better that they are doing something. Easing the conscience to allow more disruptive behavior elsewhere, driving a Toyota Prius while still taking the private jet to Cannes.

You say that parrot fishes have the highest mortality of the 4 groups in discussion. I can belive that but I think that Batfish would be a very close second if not actually worse than parrot fish. For certain in total numbers killed in the trade there are many more (probably orders of magnitude) batfish killed than parrot fish. Many more batfish are brought in and many more in number of batfish die. But speaking just in total numbers killed in the trade then it would have to be tangs. Due to the huge numbers of tangs brought in I am sure that there are many more killed in the trade than either batfish or parrot fish. I think that the numbers of parrot fish brought in that die in the trade are almost insignificant to the reef, maybe not so insignificant with the number of tangs brought in.

I would like to know more about the study that showed batfish outcompeting both tangs and parrot fish for eating macroalgae. Was that test done in a tank or some other disrupted habitat that may have changed behavior ? I have spent a significant amount of time underwater on Indo Pacific reefs and can not remember ever seeing batfishes feeding on macroalgae. That does not mean that they do not, I have just not observed it personally. I have however watched many thousands of parrot fishes and tangs happily eating algae all day long. They rarely stop eating algae except to sleep or move on to another feeding spot. It goes in one end and out the other all day long. Batfishes on the other hand are often seen just hanging around and not feeding. It would lead me to believe that their digestive systems are different and they do not need to feed constantly as the parrots and tangs do. I am very interested to see how the study you quote comes to the conclusion that batfishes out compete tangs and parrot fishes for macroalgae as food.

Please do not take any of the above to mean that I am in favor of banning animals from the aquarium trade. I am strongly of the opinion that the aquarium trade is benificial to wild reefs as long as collection is done in a sane and thoughful manner. I have seen many, many villages that collect aquarium animals recieve the money that they need to survive from the aquarium industry. The only other option that these villages have to get needed income is to turn to food fish collection or to sell their trees for harvest by logging companys. They do not have other options, there is no infrastructure there for any other type of employment. By harvesting aquarium fish they make the money that they need for survival and their reefs become valueble to them and they will protect that which feeds them. When they have to sell their trees to survive it starts a cycle of destruction that generally ends with the end of the village, the people move to town and live with relatives and all sorts of social problems erupt ending with war and killing. If that sounds overdramatic then you need to spend some time in the Solomons, Fiji, or Papua New Guinea and you will see it first hand.

Sorry I got side tracked and turned into a bit of a rant at the end.

Back to herbivorous fishes I hope.

Dave

 

[Ret_Talbot]

I find this discussion quite interesting. Please do not take anything that I say as negative or even challenging, I am just throwing out some ideas and observations that I have as food for thought.

First off are you suggesting that the trade make a self imposed ban on parrot fish to show those outside of the hobby that we care and can organize to action, or is the purpose to actually help the wild reefs in some way. Considering the effort that it will take to bring about a self imposed ban in this industry would it be better to target something that will have meaningful impact on the reef ? As an analogy to the personal computer recycling you brought up, if we have the power to change something would it be best to have all personal computers recycled (small improvement) or go for something that will really have an impact and have all electronic products recycled ? IF the aquarium trade could agree to a self imposed ban would it not be better to ban Yellow Tangs rather than the odd parrot fish that is brought in? Or ban Tangs altogether as a family ? I don't see the good of banning something of little impact. It would be an easier job to get the trade to self ban parrot fish than it would be for tangs as we really don't want or need the parrots already, but would it really make a difference to the reef or only make some folks feel better that they are doing something. Easing the conscience to allow more disruptive behavior elsewhere, driving a Toyota Prius while still taking the private jet to Cannes.

You say that parrot fishes have the highest mortality of the 4 groups in discussion. I can belive that but I think that Batfish would be a very close second if not actually worse than parrot fish. For certain in total numbers killed in the trade there are many more (probably orders of magnitude) batfish killed than parrot fish. Many more batfish are brought in and many more in number of batfish die. But speaking just in total numbers killed in the trade then it would have to be tangs. Due to the huge numbers of tangs brought in I am sure that there are many more killed in the trade than either batfish or parrot fish. I think that the numbers of parrot fish brought in that die in the trade are almost insignificant to the reef, maybe not so insignificant with the number of tangs brought in.

I would like to know more about the study that showed batfish outcompeting both tangs and parrot fish for eating macroalgae. Was that test done in a tank or some other disrupted habitat that may have changed behavior ? I have spent a significant amount of time underwater on Indo Pacific reefs and can not remember ever seeing batfishes feeding on macroalgae. That does not mean that they do not, I have just not observed it personally. I have however watched many thousands of parrot fishes and tangs happily eating algae all day long. They rarely stop eating algae except to sleep or move on to another feeding spot. It goes in one end and out the other all day long. Batfishes on the other hand are often seen just hanging around and not feeding. It would lead me to believe that their digestive systems are different and they do not need to feed constantly as the parrots and tangs do. I am very interested to see how the study you quote comes to the conclusion that batfishes out compete tangs and parrot fishes for macroalgae as food.

Please do not take any of the above to mean that I am in favor of banning animals from the aquarium trade. I am strongly of the opinion that the aquarium trade is benificial to wild reefs as long as collection is done in a sane and thoughful manner. I have seen many, many villages that collect aquarium animals recieve the money that they need to survive from the aquarium industry. The only other option that these villages have to get needed income is to turn to food fish collection or to sell their trees for harvest by logging companys. They do not have other options, there is no infrastructure there for any other type of employment. By harvesting aquarium fish they make the money that they need for survival and their reefs become valueble to them and they will protect that which feeds them. When they have to sell their trees to survive it starts a cycle of destruction that generally ends with the end of the village, the people move to town and live with relatives and all sorts of social problems erupt ending with war and killing. If that sounds overdramatic then you need to spend some time in the Solomons, Fiji, or Papua New Guinea and you will see it first hand.

Sorry I got side tracked and turned into a bit of a rant at the end.

Back to herbivorous fishes I hope.

Dave

Dave,

I'm so glad you are inclined to engage in the dialog, and I am not offended be anything you have said. By the way, I agree with your self-proclaimed rant at the end regarding the valuable role the aquarium trade plays in remote villages of the developing world. Combine that with the fact that the marine aquarium trade, IMO, raises valuable awareness about reefs and reef species on the other end of the chain of custody, and a very strong argument can and should be made for the continuation and expansion of a robust, albeit sustainable, trade in marine ornamentals.

...but back to herbivorous fishes. You have consistently brought up tangs (and specifically the yellow tang) as a comparison. I have been trying to wrap my mind around the tang question, and I am still at quite a loss. While anecdotally there is clearly a problem that needs addressing, the science is either not there or not available (or I have simply missed it). Many of the marine researchers I have interviewed who focus on herbivores agree that there is quite a buzz about yellow tangs, but almost all are of the opinion that the jury is still out on them.

The reason I threw out the parrotfish as a "for example" earlier in this thread is because, unlike the yellow tang, other surgeonfishes and rabbitfishes, the yellow parrotfish is decidedly unsuitable for most home aquaria (e.g. most die within a month of capture). No doubt more tangs die in the chain of custody overall because more tangs are targeted, captured, shipped, held, and, eventualy, sold. I am hopeful that the continuation of better collection methods and better husbandry by collectors, wholesalers, retailers, and aquarist will continue to lower mortality along the chain of custody. Unfortunatly, the same cannot be said of parrotfishes, as successful husbandry in captivity may well remain illusive except for at public aquaria and exceedingly large private facilities. That is why my discussion has focused on the parrotfish--it has a very high mortality rate in captivity.

Add to that high captive mortality rate the notion that this is a potentially critical herbivore on tropical reefs facing phase shifts away from coral dominated environments toward coral dominated environments, AND researchers studying these fishes are actively seeking their increased protection until more is known about their functional role/capacity. Am I saying that self-regulating the industry by voluntarily banning parrotfishes will save tropical reefs? No. Stopping overfishing of adult queen parrotfishes for food would do that. What I am saying is that a self-imposed ban with associated customer education could raise awareness amongst aquarists for ALL herbivorous fishes and the critical role they play on degraded reefs.

One way to do this might be to approach the online big boys of LiveAquaria, Marine Depot Live, Blue Zoo Aquatics, Saltwaterfish.com, and maybe Vivid (who else?) and see if they would all get on board with a self-regulated ban AND (the really important part) an education campaign (e.g. press release by each company, text on the product page explaining why the company is not offering that fish for sale except for to publisc aquaria and researchers). This has the potential to be something the retailers might agree to as parrotfishes are not a huge part of their business, and, with the right educational campaign, it has the potential to educate aquarists about the role of all herbivorous fishes. To answer you earlier question directly, the benefit of the self-imposed ban would be primarily education. I don't know, just a thought....

Anyway...on to other stuff. Ya, batfish IME/IMO do better in aquaria if given the right habitat, which is, of course, a big if. In a sufficiently large aquarium, the advanced aquarist should be able to meet the batfish's dietary needs, and the batfish will adapt to captive life much better than the captive parrotfish that seems to exist in a constantly stresses state in almost every home aquarium I have seen. You are right, however, that poor purchasing decisions and poor husbandry probably kill just as many batfish as parrotfish, as more batfish are imported and sold in the trade (I have NO DATA to back up anything I am saying here...lol...just thought you should know...).

Regarding batfishes as herbivores, you will want to check out Dr. David Bellwood's work and the article “The Sleeping Functional Group Drives Coral-Reef Recovery” published in Current Biology in December 2006. To paraphrase some of Bellwood's work, it was the pinnate batfish (Platax pinnatus), generally considered an invert feeder, that outgrazed macroalgae assays (replicating a degraded, algae dominated reef habitat). The 43 herbivorous fishes in the local fauna played only a minor role in the grazing of established macroalgae when compared to the pinnate batfish, according to Bellwood's research. It was clearly the batfish that was primarily responsible for driving the phase-shift reversal of an algae-dominated reef to a coral-dominated reef. Bellwood told me that he was shocked. "[D]espite more than 50 years of SCUBA-based research on coral reefs, we were totally unaware of the fishes responsible for reversing the most widely documented phase shift in reef ecosystems.”

Does this mean we should ban the pinnate batfish in the trade? Indeed it may. If this fish is critical to the recovery of degraded reefs, and its numers are struggling (it recruits in mangrove root biotopes which are being hammered by coastal development), then we probably should take a look at the aquarium trades impact. Again, more data is needed as researchers begin to rethink what we thought we knew about herbivorous fishes.

At the very least, in my mind as both a journalist and an aquarist, it is interesting food for thought.

 

[clarionreef]

David,
You are indeed so very polite.
I to would like to borrow your disclaimer if I may;
Please do not take anything that I say as negative or even challenging, I am just throwing out some ideas and observations that I have as food for thought.

Bellwood bats;
I was intrigued by Bellwoods notions....I have no doubt it is true but what significant population of pinnatus are we talking about? I have seen schools of 30 giant two footers but they are few and far between. I wish him to be correct because that would mean that they are doing pretty well at least somewhere. The Barrier Reef no doubt.... where the tropical fish trade is an insignificant extractor of biomess from the reef and no one eats pinatus!.

Food fishes % vs. aquarium fishes...pretty much no contest. It should be obvious that the aquarium trade takes much, much smaller amounts of non breeder sized fishes in most of the herbivore genera, especially the parrots.
I just spent the day in a village that brought in more stringers of tangs, parrots and rabbits then you could shake a stick at and they do it every single day 'cept Sunday [ the day of atonement?]
I am quite sure that there is little interest to truly understand what tonnage of reef fishes is removed routinely by village fishers juxtaposed to aquarium fishers in any matchup.
The results, the comparison would be so vast as to seem insignificant! [which is by the way, why the Australian governnment has granted such huge quotas to their fish collectors. Even they were surprised by their own calculations ]
Villagers in every fishing vilage need to eat every day...and they do! They spear or gillnet every shallow water edible herbivorous fish above 6 inches and do so relentlessly!
Tropical fish collector villages are numerically tiny in comparison...many entire countries have zero tropical fish trade and their problems are often identical to the rest.[ Indo and P.I. notwithstanding]

Tokenism and the creation of alarm
Remember the song..." if ya cant be with the one ya love...love the one you're with?"
Kinda like the search for issues to be concerned about.
If ya can't be with the ones that count, be with the ones that dont....and just create a greater buzz about them.
In any search for alarms to generate interest...we have seen;
1. Responses to alarming realities to actually help the condition of coral reefs.
2. Searches for alarm to satisfy some personal need.
3. Searches for alarms to generate funding....
Clearly by now at RDO-U....[.ie. RDO University] we have learned that looking for a cause to generate funding for is the biggest and most fashionable reason to care about reefs these days.
In James Cook University in fact, an alarm went out by one researcher to save the Great Barrier reefs because if we don't a species of coral feeding butterflies ie. C. trifascialis, [ the chevron butterfly ] would be in trouble.
[ heedless of the inconvenient fact that no one in Australia takes them as they are "coral feeding worthless" ] The researcher who knew nothing of the aquarium trade simply assumed that the trade took them as there was no other possible, pin-pointable suspect and the aquarium trade always gets picked for the line-up anyway]


Hoping to find a blame that we actually have something to do with and the ability to affect is difficult I know....especially creating alarm from the West on issues in the rest of the world far away.

Many of us in the trade actually know what the worst thing we do is...and the reason we put up with outsiders nominating and playing with the issues is that they seem to always get it wrong.
If they actually listened to us, there would be more hell to pay.
Whistle blowing from within garners few allies in the trade and fewer outside...as the real, core issues are often too complicated, integrated with inconvenient cultural/political realities and are just not simple to solve from some convenient, comfortable on-line position.

NOTHING WE EVER DO IN HIS TRADE even approaches the damage we finance, subidize, enable, cause, create and pay for in the acceptance and tolerance of coral killing collecting methodologies.
Habit is the key and always has been.
Ruining, breaking, poisoning habitat deletes the next generations...or starts em down the slippery slope.
Habitat is critical, habitat is key, habitat is in fact the very environment itself which is quickly forgetten in the off track seach for the more charasmatic and limited "side issue-lets".
PS. IMHO

Steve

 

[Ret_Talbot]

David,
You are indeed so very polite.
I to would like to borrow your disclaimer if I may;
Please do not take anything that I say as negative or even challenging, I am just throwing out some ideas and observations that I have as food for thought.

Bellwood bats;
I was intrigued by Bellwoods notions....I have no doubt it is true but what significant population of pinnatus are we talking about? I have seen schools of 30 giant two footers but they are few and far between. I wish him to be correct because that would mean that they are doing pretty well at least somewhere. The Barrier Reef no doubt.... where the tropical fish trade is an insignificant extractor of biomess from the reef and no one eats pinatus!.

Food fishes % vs. aquarium fishes...pretty much no contest. It should be obvious that the aquarium trade takes much, much smaller amounts of non breeder sized fishes in most of the herbivore genera, especially the parrots.
I just spent the day in a village that brought in more stringers of tangs, parrots and rabbits then you could shake a stick at and they do it every single day 'cept Sunday [ the day of atonement?]
I am quite sure that there is little interest to truly understand what tonnage of reef fishes is removed routinely by village fishers juxtaposed to aquarium fishers in any matchup.
The results, the comparison would be so vast as to seem insignificant! [which is by the way, why the Australian governnment has granted such huge quotas to their fish collectors. Even they were surprised by their own calculations ]
Villagers in every fishing vilage need to eat every day...and they do! They spear or gillnet every shallow water edible herbivorous fish above 6 inches and do so relentlessly!
Tropical fish collector villages are numerically tiny in comparison...many entire countries have zero tropical fish trade and their problems are often identical to the rest.[ Indo and P.I. notwithstanding]

Tokenism and the creation of alarm
Remember the song..." if ya cant be with the one ya love...love the one you're with?"
Kinda like the search for issues to be concerned about.
If ya can't be with the ones that count, be with the ones that dont....and just create a greater buzz about them.
In any search for alarms to generate interest...we have seen;
1. Responses to alarming realities to actually help the condition of coral reefs.
2. Searches for alarm to satisfy some personal need.
3. Searches for alarms to generate funding....
Clearly by now at RDO-U....[.ie. RDO University] we have learned that looking for a cause to generate funding for is the biggest and most fashionable reason to care about reefs these days.
In James Cook University in fact, an alarm went out by one researcher to save the Great Barrier reefs because if we don't a species of coral feeding butterflies ie. C. trifascialis, [ the chevron butterfly ] would be in trouble.
[ heedless of the inconvenient fact that no one in Australia takes them as they are "coral feeding worthless" ] The researcher who knew nothing of the aquarium trade simply assumed that the trade took them as there was no other possible, pin-pointable suspect and the aquarium trade always gets picked for the line-up anyway]


Hoping to find a blame that we actually have something to do with and the ability to affect is difficult I know....especially creating alarm from the West on issues in the rest of the world far away.

Many of us in the trade actually know what the worst thing we do is...and the reason we put up with outsiders nominating and playing with the issues is that they seem to always get it wrong.
If they actually listened to us, there would be more hell to pay.
Whistle blowing from within garners few allies in the trade and fewer outside...as the real, core issues are often too complicated, integrated with inconvenient cultural/political realities and are just not simple to solve from some convenient, comfortable on-line position.

NOTHING WE EVER DO IN HIS TRADE even approaches the damage we finance, subidize, enable, cause, create and pay for in the acceptance and tolerance of coral killing collecting methodologies.
Habit is the key and always has been.
Ruining, breaking, poisoning habitat deletes the next generations...or starts em down the slippery slope.
Habitat is critical, habitat is key, habitat is in fact the very environment itself which is quickly forgetten in the off track seach for the more charasmatic and limited "side issue-lets".
PS. IMHO

Steve

Steve,

Thanks so much for this-I take no offence at anything said. I just love the conservation, as I think it makes us all more aqware and thoughtful in the long run.

I agree with so much of what you say, and indeed I do think habitat is critical. That's actually what brought me to herbivorous fishes in the first place. I was thinking long and hard about degraded reefs (after a recent trip to the Caribbean), and I was curious, as others have expressed here, why reefs that seemed to have huge populations of known herbivores were so completly overgrown with macroalgae.

I am not here to promote anyone's academic or enviornomental agenda. I simply in aksing a lot of questions and talking to a lot of people and letting it lead me where it does. That's one of the reasons I try to always dedicatea portion of my research on any project to initiating discussions in forums like this and soliciting all feedback. As we all know, there always a lot of talk in this industry about what we should or should not do based on anecdotal evidence, which is fine, but I'm always intrigued to apply a spattering of acadmic rigor to the mix and look to the peer-reviewed, published data. As you've pointed out, we lack a lot of data, and it's not just in the marine aquarium industry. I have been on the forefront of collecting data on global climate change from some of the most remote, unstudied places on the globe for just that reason--no data was present. In some of those cases, our methods for collecting data were unconventional at best, but they were inclusive and cheap and something that remote villagers could do withour grants and fancy equipment. A lot more needs to be learned in this way IMHO, but I digress.

Ya...the pinnates Bellwood was looking at were on a GBR reef, and it's a little scary in terms of what impact coastal development could have on them (especially as mangroves are bulldozed) if the truly do prove to be an important player in phase shift reversal. I just thought it was so damn cool to hear what he had seen--a big old batfish munching macroalgae with gusto that put all the other herbivorous fishes to shame...lol. How little we know, eh? By the way, Bellwood is an aquarists and wholeheartedly agrees that rabbits, for example, make great herbivorous aquarium fishes.

Anyway, I want to be clear that I have never once claimed that the aquarium trade is more responsible for the overfishing of just about any fish (with the exception of maybe the Banngai) than the food fishing industry. The food fishing industry needs to get its act together no doubt, as does the sport fishing industry, and I write a fair bit about both. As an aquarist, however, I am always looking for how my interest in the hobby--both personal and professional--is connected to wild ecosystems and wild populations of the species we keep in aquaria. I am not, as some may have assumed, casting around for a cause or trying to drum up support for some enviro-polit agenda. I am not scare mongering or anything else along those lines. I simply love looking for opportunitie to bring my passion for the hobby, for marine science and for thoughtful (pragmatic) conservation together, and that's what I'm currently doing with this herbivorous fishes research.

In short, I don't see my work as tokenism, and I sleep fine at night as it is...lol... Having the conversation and bringing divergant ideas to the table is, in my opinion, always beneficial. We can always do things better. Can't we? Anyway, please continue to be part of the discussion, and, Steve, I would love to sit down with you and tell the story you think needs to be told. I'll meet you wherever, as being in the field, in my experience, is the only way to get the real story.

Cheers!

 

[Fish_dave]

To clarify I brought up tangs and yellow tangs in specific because there has already been much similar discussion about tangs, their suitability for home aquaria, and their importance to reef health. I was leaning on that earlier discussion to make a point without repeating all previous points. Not proper I know but I did it anyway.

In my opinion I do not think that we should have a ban on any animal in the aquarium trade unless it can be shown to be threatened in the wild or that collection of the animal threatens the existance of itself or another species. For instance I agree totally with the ban to bring sea turtles in for commercial gain. The trade in some species needs to be banned in order to protect its existance in the wild. I do not think that is the case for parrot fish.

The problem I see with having a ban on a species due to poor survival or poor adaptation to captivity is that there are so many different opinions on what is and is not acceptable that soon a case will be made to ban virtually everything. This discussion has been made several times in this forum alone. One person wants to ban tangs and cleaner wrasse, another ribbon eels, another all wild clown fish, and you would propose a ban on parrot fish. The guy with a happy parrot fish in his tank would not be agree with the parrot fish ban. The thousands of people who enjoy tangs in their home tanks would not like to see a ban on tangs. The guys with ribbon eels that are eating and thriving love their eels and do not want to see them banned. Most of all the poor guy out on the reef collecting does not want to see anything taken away from his livelyhood. There are collectors that collect only tangs, some that collect only clown fish, etc. (I do not know of any that collect only parrot fish). When we start talking of a ban it becomes a personal agenda of folks who have strong opinions of what lives and does not, what is proper to keep and what is not.

I personally think that Pinnatus bat fish have a dismal record of living in home aquaria. I do not think that they should be banned but I chose to import very few of them. I used to think that they were virtually impossible to keep until a friend of mine purchased 6 of them and kept all 6 alive and well together for over a year. I now know that they are not impossible but I still think that they are darned tough to keep alive. Does that warrant a ban ? Not in my opinion.

You state that you feel that in your opinion batfish should have a better chance of survival in home aquaria than parrot fish. I think that this is a personal observation from a fairly limited sample and I think would exclude the pinnatus batfish. In my experience I have seen many more surviving parrot fish than pinnatus batfish. I do not think that parrot fish are great aquarium fish but I have seen many adapt and do quite well in aquariums. It would be interesting to have a survey done on reef central or somewhere average aquarists hang out to see how many have had sucess with juv. parrot fish compared to who has had success with bat fish and pinnatus bats in specific.

I do not have acess to "Current Biology" and have not read the article you reference. From my limited experience I have a hard time believing that Pinnatus batfish out grazed 43 other species of herbivorus fish. I have never seen pinnatus batfish in large enough numbers in the wild to think that they could consume more algae than a school of hundreds of parrot fish or tangs. I just realized that I am thinking of pinnatus batfish in the juv. form as that is all that interests me when diving. I suppose that an adult fish may consume quite a lot of algae. But then again I have the problem of always seeing schools of bat fish just hanging out doing nothing while the parrots and tangs seem to be in search and destroy mode when it comes to attacking the reef for algae. I will try to look up the article as the thought that pinnatus batfish could consume that much algae is interesting.

Again both the fish that we are talking about, parrot fish and pinnatus bat fish I agree do not make very good aquarium fish. I would not support a ban on the fish but in my case I bring in very few due to my feelings about them. Pinnatus are so delicate that they are often damaged in shipping and I do not like to bring in fish that I can not sell so I make the economic decision to not bring many in. Parrot fish I just don't like much so I bring in very few. I doubt if I bring in more than 20 parrot fish in a year and no more than 25 - 30 pinnatus batfish per year. It is in effect a personal ban on the fish but if someone else wants to bring in 100 or 200 or whatever I think that they should be able to unless there is a sound case made that it is threatened in the wild.

There are a few more of my rambling thoughts on things.

Dave

 

[Ret_Talbot]

Habitat is critical, habitat is key, habitat is in fact the very environment itself which is quickly forgetten in the off track seach for the more charasmatic and limited "side issue-lets".
PS. IMHO
Steve

By the way, Steve, I'm interested to know what you think of marine reserves and no take zones. When it comes to habitat, so many of the researchers I have interviewed advocate these, and they are such flash points for aquarium hobbyists and fisherman. I'd love to know your thoughts in this regard...

 

[Ret_Talbot]

The problem I see with having a ban on a species due to poor survival or poor adaptation to captivity is that there are so many different opinions on what is and is not acceptable that soon a case will be made to ban virtually everything. This discussion has been made several times in this forum alone. One person wants to ban tangs and cleaner wrasse, another ribbon eels, another all wild clown fish, and you would propose a ban on parrot fish. The guy with a happy parrot fish in his tank would not be agree with the parrot fish ban. The thousands of people who enjoy tangs in their home tanks would not like to see a ban on tangs. The guys with ribbon eels that are eating and thriving love their eels and do not want to see them banned. Most of all the poor guy out on the reef collecting does not want to see anything taken away from his livelyhood. There are collectors that collect only tangs, some that collect only clown fish, etc. (I do not know of any that collect only parrot fish). When we start talking of a ban it becomes a personal agenda of folks who have strong opinions of what lives and does not, what is proper to keep and what is not. Dave

Dave,

This is a really solid point. I hear you on all points here. In principle regarding any sort of ban on anything, we are entirely in concert. You've made me realize that I'm really looking for a delivery device for education--that's what I really want, and a ban is probably not the best way to go about it, but it is a slippery slope. This example is FAR, FAR, FAR worse than my last analogy (lol), but here goes. Even though I don't believe bans are in keeping with my own personal philosophy for many of the reasons you have brought up, I still think a ban on automatic assault weapons in urban areas is a really good idea. Anyway...thanks for your comments above...helps me to clarify. As I think you know, my job is to write, and like any profession, I appreciate it when people can help put the issues with which you deal daily into perspective. As they say in Scotland, "Good on ya!"

 

[Ret_Talbot]

I personally think that Pinnatus bat fish have a dismal record of living in home aquaria. I do not think that they should be banned but I chose to import very few of them. I used to think that they were virtually impossible to keep until a friend of mine purchased 6 of them and kept all 6 alive and well together for over a year. I now know that they are not impossible but I still think that they are darned tough to keep alive. Does that warrant a ban ? Not in my opinion.

Dave

I agree. This warrants education, not a ban. In an ideal world, every retailer (online or LFS) would educate their customers that batfishes are an expert only species with very specific husbandry requirements. When you adopt a kid, you have to prove you can care for the little shiner, right?

 

[Ret_Talbot]

You state that you feel that in your opinion batfish should have a better chance of survival in home aquaria than parrot fish. I think that this is a personal observation from a fairly limited sample and I think would exclude the pinnatus batfish. In my experience I have seen many more surviving parrot fish than pinnatus batfish. I do not think that parrot fish are great aquarium fish but I have seen many adapt and do quite well in aquariums. It would be interesting to have a survey done on reef central or somewhere average aquarists hang out to see how many have had sucess with juv. parrot fish compared to who has had success with bat fish and pinnatus bats in specific.
Dave

Yea....I agree. Let's put our heads together on this in PM and see how best to get the anecdotal data from aquarists with experience with both parrotfishes and batfishes. My comment was based on the face that my experience has been that feeding is an issue with both fishes, but let's assume, for the moment, the experienced aquarists is knowledgable and dedicated enough to meet the dietary requirements of each. Now we come to habitat, and, again for the present discussion, let's assume the experienced aquarist is knowledgable and committed enough to provide the right habitat. In my experience (and it is obviously limited, as I am only one person with a limited number of friends with an addiction to marine aquarium-keeping), the parrotfish with the right diet and right habitat is more stressed in captivity than the batfish. Again, simply IME/IMO. Let's chat more on this though, Dave. Shoot me a PM if you have time and let's set up a survey.

 

[Ret_Talbot]

I do not have acess to "Current Biology" and have not read the article you reference. From my limited experience I have a hard time believing that Pinnatus batfish out grazed 43 other species of herbivorus fish. I have never seen pinnatus batfish in large enough numbers in the wild to think that they could consume more algae than a school of hundreds of parrot fish or tangs. I just realized that I am thinking of pinnatus batfish in the juv. form as that is all that interests me when diving. I suppose that an adult fish may consume quite a lot of algae. But then again I have the problem of always seeing schools of bat fish just hanging out doing nothing while the parrots and tangs seem to be in search and destroy mode when it comes to attacking the reef for algae. I will try to look up the article as the thought that pinnatus batfish could consume that much algae is interesting.

Dave

I know it's a crazy idea to wrap one's head around. lol. Let me clear though as I don't want to misrepresnt Dave's work. I don't think he is suggesting that large shoals are commonly cruising around taking out algae. What he is saying is that bite-for-bite, and only in relation to well-established macroalgae, the pinnate batfish he observed on remote video of study sites took down the algae better than any of the known suspects. This suggests that the pinnate batfish may be a so-called sleeper functional group. These sleeper functional groups may only "show their stuff" when a phase shift has occured, and so it should not surprise us that we have not seen them munching algae on reefs already well grazed by the usual suspects. At least that's the way I understand it based on my reading of his work and the interviews I have conducted. By the way, he's a hell of a nice guy with an interest in marine aquaria to boot!

 

[Ret_Talbot]

Again both the fish that we are talking about, parrot fish and pinnatus bat fish I agree do not make very good aquarium fish. I would not support a ban on the fish but in my case I bring in very few due to my feelings about them. Pinnatus are so delicate that they are often damaged in shipping and I do not like to bring in fish that I can not sell so I make the economic decision to not bring many in. Parrot fish I just don't like much so I bring in very few. I doubt if I bring in more than 20 parrot fish in a year and no more than 25 - 30 pinnatus batfish per year. It is in effect a personal ban on the fish but if someone else wants to bring in 100 or 200 or whatever I think that they should be able to unless there is a sound case made that it is threatened in the wild.

Dave

I hear you, and I agree in philosophy, and yet there is a part of me that wants someone else to tell people living in Washington D.C. that they can't buy an automatic assault weapon....lol.

Seriously, though, I think one thing we need to consider is what "threatened" means. As Steve pointed out, it's got to be about habitat (which is, of course, the problem with CITES, but let's leave that discussion to another thread...lol).

When we talk about a species' sustainability, we should be talking about (IMO), the species' sustainability in terms of its ecological function. For example, that popular aquarium fish commonly known as the Algae Terminator (macroalgaemuchus nukealiptus), you've heard of it, right? Well anyway, it's the best algae grazer ever...and m. nukealiptus numbers are plentiful in the wild and certainly it can't be considered threatened for extinction.

But then Ineedagrant Researcher tells us, "WAIT!" While m. nukealiptus exists in numbers large enough to support species survival, the numbers are not large enough to any longer allow the species to fulfill its ecological role as a primary algae-grazer on the reef. In other words, the species will survive, but the habitat may not.

IMO we must be talking about sustainabilty in terms of ecosystem function as opposed to species extincton.

 

[Fish_dave]

These have been some interesting ideas. Leave it to Steve to point out to me where there are numbers of batfish large enough to do what was proposed, I had not thought of the fact that no one wants to eat pinnatus from the great barrier reef. Reminds me of one night long ago in the Solomons sitting next to a little fire and eating black fish, fish thrown right into the fire and then taken out when black, cracked open and eaten. I ate a goat fish and an orbic batfish. Not sure wich one it was that got me but I got sick for the next week and truely thought that I was going to die. I was SICK, much worse than the malaria that came later.

Good points here, thanks for the discussion. That's it for me today, I am off to do something other than hang around the warehouse 24/7.

Dave

 

[Ret_Talbot]

These have been some interesting ideas. Leave it to Steve to point out to me where there are numbers of batfish large enough to do what was proposed, I had not thought of the fact that no one wants to eat pinnatus from the great barrier reef. Reminds me of one night long ago in the Solomons sitting next to a little fire and eating black fish, fish thrown right into the fire and then taken out when black, cracked open and eaten. I ate a goat fish and an orbic batfish. Not sure wich one it was that got me but I got sick for the next week and truely thought that I was going to die. I was SICK, much worse than the malaria that came later.

Good points here, thanks for the discussion. That's it for me today, I am off to do something other than hang around the warehouse 24/7.

Dave

Reminds me of a similar night on the beach in Baja after being "winded-in" for 12 days with only a spear gun and a dwindling supply of freshwater. Tossed a trigger on the fire that night, but it was the water collected from a pothole and strained through three t-shirts that made me sick for the next six months (I think). Have a great night, Dave!

 

[Fish_dave]

One more though before I bow out.

I agree with the eco-system function sustainability. One large problem that I have with most science about what is and is not sustainable etc. is that there seem to me to be many more of the Ineedagrant/givememoney researchers out there saying what ever they need to get funded than there are the Itellitlikeitreallyis researchers.

One thing to keep in mind on the aquarium side of things is that we really target mainly juveniles of most species. Certainly with Bat fish we want only juveniles for the aquarium trade and the juv. mortality rate in the wild is huge. If for instance one in a thousand juv fish make it to adult hood then taking a juv fish from the reef has much less impact than say taking an adult fish to eat. Most researchers that are anti aquarium industry fail to take this into account. I have seen data from several years of research in French Polynesia and also the Virgin Islands that support the fact that with most tangs, damsels, and yes parrot fish the mortality from time of first settlement on the reef to adulthood is closer to 10,000 to one. In some species approaching 100,000 to one. By taking juv fish of aquarium size I don't think that it is unreasonable to figure that it may be close to 1,000 to one making it to full adult size.

Dave

 

[Ret_Talbot]

One more though before I bow out.

I agree with the eco-system function sustainability. One large problem that I have with most science about what is and is not sustainable etc. is that there seem to me to be many more of the Ineedagrant/givememoney researchers out there saying what ever they need to get funded than there are the Itellitlikeitreallyis researchers.

One thing to keep in mind on the aquarium side of things is that we really target mainly juveniles of most species. Certainly with Bat fish we want only juveniles for the aquarium trade and the juv. mortality rate in the wild is huge. If for instance one in a thousand juv fish make it to adult hood then taking a juv fish from the reef has much less impact than say taking an adult fish to eat. Most researchers that are anti aquarium industry fail to take this into account. I have seen data from several years of research in French Polynesia and also the Virgin Islands that support the fact that with most tangs, damsels, and yes parrot fish the mortality from time of first settlement on the reef to adulthood is closer to 10,000 to one. In some species approaching 100,000 to one. By taking juv fish of aquarium size I don't think that it is unreasonable to figure that it may be close to 1,000 to one making it to full adult size.

Dave

Once again, Dave, excellent points. For the record, I have been really clear with all researchers I have interview that while I am pro-aquarium industry, they absolutely do not have to be in order to get air time with me. Many of them, like Peter Mumby, have talked about adults being the issue for them, so I think most of us may be on the same page here. Enjoy your, Sunday, Dave.

 

[dizzy]

p.s. - batfishes are omnivores with a strong tendency towards being carnivores.

I agree. IME they (Platax teira, P. obicularis) can live quite successfully as strictly carnivores. Small batfish are vulnerable to fin nippers, but grow amazingly fast. A lot of batfish outgrow their aquarium environment and people want to trade them in to the pet store. I have seen several that had deformed dorsal fins from obviously being kept in tanks that were too small for them. They get to large for most tanks, and are not very colorful(juv pinnatus excepted), but they do have charming personalities. I remember people saying to feed the pinnatus bananas but I don't think that was the answer. I agree that occasional one can be kept. Probably once the proper juvenile food is found they won't be much more difficult than orbie or teiras. I never tried keeping one in a reef tank or feeding them nori.
Mitch

 

[Ret_Talbot]

p.s. - batfishes are omnivores with a strong tendency towards being carnivores.

I agree. IME they (Platax teira, P. obicularis) can live quite successfully as strictly carnivores. Small batfish are vulnerable to fin nippers, but grow amazingly fast. A lot of batfish outgrow their aquarium environment and people want to trade them in to the pet store. I have seen several that had deformed dorsal fins from obviously being kept in tanks that were too small for them. They get to large for most tanks, and are not very colorful(juv pinnatus excepted), but they do have charming personalities. I remember people saying to feed the pinnatus bananas but I don't think that was the answer. I agree that occasional one can be kept. Probably once the proper juvenile food is found they won't be much more difficult than orbie or teiras. I never tried keeping one in a reef tank or feeding them nori.
Mitch

There is no disagreement here as to their ususal diet. The point is that in studies they have proved a sleeper functional group capable of doing what no other fish could achieve efficiently--reverse a phase shift. That's interesting, no?