what size of wild reef does the hobby consume?

[threeheaddog]

eg. does all the biomass in the hobby as of now compare to the reef biomass of lets say all the mashall islands?

how could you calculate this?

what does this mean? impact level?

what is the total biomass and habitat consumed by the hobby?

where can you reference this?

[PRC]

If you really want to know, you can probably get a pretty decent estimate, but it's going to take some work. You can start at the CITES web site ( http://www.cites.org ) where you can find quotas for all protected species. Try looking under 2003 since I don't think the 2004 data is complete yet. There you will find quotas on specific species for specific countires (Fiji for example: http://www.cites.org/eng/resources/q...003/fiji.shtml ).
Next you'd need to estimate the density of these organisms on the reef. You could do this as a general estimate for all species or, if you really want to go all out you could try to estimate it for each individual species. Not sure where you'll find this type of info, though I'm sure someone has done some studies on this. You might try asking Eric over in his forum.
Live rock should be easy. Just estimate the mass per unit volume(ie. kg per cubic meter) and divide. For example, Fiji exported about 1.4 Million kg of LR in 2003. Let's say LR is 400kg/cu meter (just a guess). So that's about 3,500 cubic meters of LR, or a reef one meter high by three meters wide by about 1.2 km long.
My guess is it won't be nearly the size of all the Marshall Islands reefs, but more likely several good sized South Pacific patch reefs.
Be very interesting to see, definitely let us know what you come up with. Oh, and always include your assumptions in any conclusions.

[PRC]

OK, since no one else is biting on this I'll give it a try. I think you can put together some reasonable estimates with very little effort. I'm going to make a lot of guesses here so feel free to shoot holes in it wherever you feel necessary.
According to the CITES data referenced above for Fiji in 2003, 155,481 corals were harvested in that country that year.
My first assumption will be that about two corals were removed from the reef environment for every one that CITES counted. I have very little to base this on, but I feel that every coral certainly was not counted for many reasons, the 2/1 ratio is a complete guess but it should get us in the ballpark. So we'll say that ~300,000 corals were removed from the reefs of Fiji in 2003.
The vast majority of these corals were acropora (48,180) and Pocillopora (33,202), mostly very fast growing species. The next most popular coral was Turbinaria at 7,398 specimens. These two species together account for more than half of the total harvest.
The next guess is how much reef area would be necessary to sustain this type of harvest. While we could also guess at how much reef would be stripped bare by this rate of removal, I'd rather go the more optimistic (and useful, I believe) route of determining the amount of reef necessary to provide sustainable harvest. So here's the next guess: one square meter of wild reef could provide five corals per year on a sustainable basis. This guess is based on the fact that the majority of the corals removed are fast growing Acropora and Pocillopora species. I think this is a very conservative estimate.
So what does this leave us with? To harvest 300,000 corals per year from a reef environment that could sustainably produce five corals per square meter per year would require 60,000 square meters of reef. That's an area a little less than 250 meters square. Don't know about you, but that's a whole lot less than I was expecting. This would be a very insignificant amount of Fiji's total reef area. Am I missing something major here?
Even if we drop the estimate down to one coral per square meter per year we end up with 300,000 square meters of reef, or about a 550 meter square. A little more substantial but certainly a small percentage of Fiji's total reef area.
According to the "World Atlas of Coral Reefs" Fiji currently has over 10,000 square km of reef. If the above assumptions are anywhere near right then .01% of Fiji's reef area could sustain the coral harvest for the aquarium industry more than three times over!
All this being said, I think the real problems are more subtle and become more apparent when you look into the details. I think the issues are more around specific types of corals which either grow much slower than Acropora and Pocillopora or have dismal survival rates in captivity.
Either way, I'll continue to buy aquacultured corals whenever possible and avoid any species that may be at risk of overexploitation. At least I'm a bit less worried about the impact of the hobby on the reefs of the world now than I was before.

[PRC]

Fiji reef area reference:
http://www.reefbase.org/resources/re...=0&country=FJI

[RustySnail]

Just a couple of thoughts/observations:

First the reefs are pretty damn vast; although they are suffering from climate change, pollution, and destruction (all forms including natural forces).

The collection is a form of destruction; and I'm not sure anyone has quantified the net impact of collection of specific ornamental species. As a whole the impact is probably low; but some specific species that reproduce/grow slowly may be impacted more than others. But the overall impact is considered by far less than any other form of reef destruction.

Your calculation may be valid; but you may still need to consider over-collection of a specific species (causing reproduction problems, and local loss of that species). Also the amount of area that a specific species can live in may be limited by many environmental factors; not simply 'reef area', but specific zones within a reef environment. So the net area that all corals collected require might be quite a bit higher than your estimate. But nonetheless; the amount of corals that inhabit a healthy reef is pretty amazing.

I am more concerned with over-harvest of specific very popular species, like turbinaria, efflo, frogspawn, hammer, brain, etc. There is much more diversity on the reef than we keep in our tanks; and much more colors than we see in stores. Most of the non eye-popping colors are simply not collected, and many colors that we would say WOW are not collected because the collectors dont know we want them (like blue LPS corals, oranges, yellows, etc).

[bookfish]

In a recent article that Eric Borneman co-wrote for Earth Island Journal he says the annual take is:
"one to two million corals"...and "40,000 to 60,000 kg of live rock"-Jim
ps. Hi Russ!

[Ira NZ]

40-60,000 KG of live rock? That seems WAY too low.

[RustySnail]

I still consider the amount collected small by comparison to the amount of reef that exists. If you just put a 'number' on it like 'millions collected' without context, it sounds like a huge impact; but if you start comparing things in volume ratios I think you might see that the amount collected is much smaller than you would otherwise think. Many/most of the colonies we see as collected specimens are miniscule in size by comparison to mature reef colonies (think of them as reef frags). The areas that corals are collected from are limited to collection stations where the reef is easily accessed and holding/shipping facilities are established (a small portion of a vast resource).

Look at a healthy reef tank for a comparison. If a reef tank were as packed with coral as a wild reef; the growth rate would be such that you would need to prune regularly, and the amount you harvest would be enough to 'starter' another tank of the same size with frags more than a few times per year. If you take that and multiply it by about a trillion (just an estimate) you would have the amount of biomass that the oceans reefs produce.

Thats JMHO; you may feel or believe differently. Personally I think the factors of pollution, and destruction by mining for concrete aggregate (yes this is being done) is destroying the reefs far faster than our 'pruning'.

[snarfe]

Originally posted by Ira NZ
40-60,000 KG of live rock? That seems WAY too low.

yeah thats what i thougth too, but i was thinking that alot of people are starting to pay attention to the conservation side of things. there are a lot of people that are getting TBS (dont' know if this would be included since it doesn't come from a reef), and people are using a lot of base rock lately. so its possible.

[bookfish]

I meant sad in the sense that we're not farming more of the corals consumed by the hobby. I know our hobby does a lot less damage than some other industries.-Jim

[squidlips02]

I personally think more coral is lost to natural attrition in the form of weather effects, going back a few years I was snorkeling around some of the islands on the great Barrier Reef, about three months after a cyclone had passed through their, all that was left was coral rubble and there was hundreds of square miles of it, cyclones in and around the Great Barrier Reef are quite common around December January. my point is one cyclone or storm can destroy more coral reef life, than we can use in our liftimes, by the way I returned to the area a few years later and you would'nt know a cyclone had been their.

[Paul B]

Although I could not even venture a guess as to how much coral we remove from the sea I do have an idea of how much of the oceans coral are dying from other causes whatever they may be. I do a lot of diving in the Caribbean and I just came back from a dive trip in Tahiti. I dove on four Islands there and I was amased that a place so isolated from anywhere had so much dead coral. Tahiti is between Australia and South America. I won't say it is half dead but I will say maybe 15% of the coral is in trouble. There are all sorts of opinions and it may be a combination of all of them.
I also dove in the Caribbean after a large hurricane a few years ago and for miles around the island the coral was covered with soil and dead. Thousands of large (6') sea fans littered the beach. I saw a brain coral almost 8' wide upside down and mostly bleached.
They don't even grow pearls anymore on most of the Tahitian Islands due to pollution, they come from a few isolated Tahitian islands away from the tourist islands.
Paul
The top pictures are all dead corals in Bora Bora. I took these pictures a few weeks ago.
I don't know exactly what type of corals these are but I saw no live ones. I also saw hundreds of dead tongue corals.

[firefish2020]

Now imagine if these "harvested corals" instead of being ripped from the oceans were just fragged out responsibly by trained individuals. The total number of frags would be 10 times the amount rendered by taking entire mother colonies. Plus the mother colonies would grow back out within a year or two and be ready for harvest again.
Just an idea,
Ron

[PRC]

Originally posted by RustySnail
Your calculation may be valid; but you may still need to consider over-collection of a specific species (causing reproduction problems, and local loss of that species)....
I am more concerned with over-harvest of specific very popular species, like turbinaria, efflo, frogspawn, hammer, brain, etc.

Agreed. Sorta what I was trying to say with: "All this being said, I think the real problems are more subtle and become more apparent when you look into the details. I think the issues are more around specific types of corals which either grow much slower than Acropora and Pocillopora or have dismal survival rates in captivity."

The main point I was trying to make was that which several others have now repeated. It does not appear as though collection for the aquarium industry is a significant contributor to reef destruction given all the other issues at hand. Once again, as mentioned above, I think collection can be an issue in some circumstances and we should all be very aware of these special issues.

The numbers I generated where just to try to get a rough idea of the situation. A lot more detailed analysis could, and probably should, be done. However, even if those numers are off by two orders of magnitude (which, I'd like to think is pretty unlikely), collection in Fiji could be done sustainably on less than 1% of the total reef area. While this doesn't account for all the details, like types of reef area, etc., I think it gives a decent rough idea of the situation.

All the numbers I used were from CITES web site. This is the organization whose responsibility it is to monitor international trade in coral (actually in all endangered species, while the corals referred to here are not recognized as endangered under CITES regulations, they are still monitored). If anyone knows how much coral is shipped internationaly from Fiji, it's CITES. Other issues may impact the total number of corals taken vs. those actually shipped, I tried to adjust for that by arbitrarily doubling the CITES count. I could see where the overall number for all corals collected everywhere could be in the one to two million range, although it seems a bit high, I guess I could still buy that number. 40,000 - 60,000 kg of LR seems way too low to me. For one it's 1/20th of the CITES number from Fiji alone. There were some strange issues with LR calculations from CITES in the past which may account for the difference, but I believe they have been addressed. Just think about it a little though and it doesn't really make sense. I have 200 kg of LR in my system alone. At these rates that would mean only 200 - 300 large (~200G) systems per year for the whole world? I don't think that adds up.

[Frick-n-Frags]

sign me up for 100kg of LR. But beyond that, it has been several years since I picked up a wild colony. I live by frag swaps almost exclusively and I know of at least one person whom I have fixed up with a pile of my frags to keep it going.

Cultured stuff(both terrestrially grown and in-situ cultured) has become almost as viable as straight harvesting and I'm sure that a growing healthy % is derived from those sources.

GO FARMERS GO!!!!!!!!!!!!!!!!!!

(just trying to shed a ray of light )

[drwonga]

I believe the aquarium industry plays a very small part in the destruction of the reefs when taken from a global sense. The big destroyers are industrial pollution, over fishing, and global climate changes (from pollution again...). I think as aquarists, we have exposure to tons of creatures that most people only see in public aquariums. We have a responsibilty to protect and educate the general public. (When you realize we know more about space then we do about our own oceans, you see what a incredible world we still have left to see. It would be ashame to have it die before we even discover it.) Whenever possible, I only purchase aquaculture live rock, or make my own. (Check out www.floridaliverock.com or www.tbsaltwater.com and www.garf.org) Aquacultured rock really looks great, and the stuff you make yourself can be custom pieces. I have a lovely cave rock that is now covered in coralline algae and looks great. Also purchasing captive raised critters, or aquacultured corals instead of wild caught species helps the environment as well as the aquarium industry (such as www.coraldynamics.com). We need to remember that we live in an ecosystem. Everything is tied to something else. For example, those wild harvested anemones are an entire ecosystem of themselves. Each is a key component to their ecosystem, if we remove that piece, it can affect animals above and below it, not to mention taking a 30+ year old anemone for yourself and having it die, is rather selfish. Regardless, right now I think if we focus on aquaculture, we can have a self-sustaining hobby that is environmentally friendly, and that's extra karma points for everyone! Inform the people, teach them, make them care. Frag a coral, save the world!