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Mutagen
01/27/2001, 08:24 PM
This one is for Dr. Ron,

I am interested in knowing what are the "typical" bacterial and planktonic densities in various eco-systems. I would like to see a comparison between:

Open ocean (Tropical)
Water over barrier reef with much water movement
Water inside lagoons or atolls with limited water exchange

Having this information in hand, it would then be interesting to compare this data to our captive systems using the various techniques frequently described, such as skimmed vs. unskimmed vs. "heavy" loading, etc. If available, it would also be interesting to have a sumamry of the types of corals found in the open, semi-open, and semi-closed systems in nature.

Is this data available for either captive or oceanic systems? Could you suggest a means to find this data or make such determinations myself.

Finally, if you have already given this data in previous publications, forgive my ignorance, and point to the article!

Thanks in advance for your time, Mutagen

rshimek
01/27/2001, 09:01 PM
Originally posted by Mutagen
I am interested in knowing what are the "typical" bacterial and planktonic densities in various eco-systems. I would like to see a comparison between:

Open ocean (Tropical)
Water over barrier reef with much water movement
Water inside lagoons or atolls with limited water exchange

Some data are there, but I don't have a lot of them in my references. I don't mean to obfuscate here, but it really doesn't appear that there are typical values for a lot of these areas.

What we as hobbyist might think of as interesting, microbiologists in the field have not addressed. For example, bacterial concentrations can vary over several orders of magnitude in just the surface layers down to about 15 cm below the open ocean surface. So there really isn't a typical value.

To the best of my knowledge, nobody has yet addressed the "water over barrier reefs with much movement," simply because this is an amazingly hard place to sample, or to put a mechanical sampler.

....Is this data available for either captive or oceanic systems? Could you suggest a means to find this data or make such determinations myself.

I would suggest you go to your local large university and do a series of data base searches (using Biosis and maybe Fisheries abstracts) using the terms you mention. See what you come up with. I did this a couple years ago and got zilch. Maybe things have gotten better.

I know Bob Stark is trying to get some data on bacterial levels in our tanks, as at least a first attempt. I don't know how that project is progressing.

Finally, if you have already given this data in previous publications, forgive my ignorance, and point to the article!

No can do, sorry.

saltshop
01/28/2001, 12:33 AM
Don't know if this exactly what you are looking for or just how accurate the numbers are but this is what I have:

Bacterioplankton: (varies by depth and location etc.)

Lizard Island GBR: 1-2.5 x 10(6) /ml

Majuro atoll Marshall Island: .89-1.36 x 10(6)/ml

Heron Island GBR: 1.26-1.78 x 10(6)/ml

Open Ocean; .05-.01 x 10(6)/ml

(Moriarty, Linley, Kopp, Sorokin)

Phytoplankton: (varies by season)

New Guinea: 12-44 x 10(3)/l

Takapoto atoll: 1 x 10(4) -10(6)/l

GBR (lagoon); 1 x 10(4) -10(5)/l

Seychelles; 3.7 x 10(6)/l

(Sournia, Ricard,Relevante, Gilmartin)


Zooplankton (biomass): (varies by time of day, season, location etc.)

Bikini atoll Marshall Islands; daytime- 147 mg/m(3) nearby ocean- 71 mg/m(3)

Heron Island GBR; night- 720 mg/m(3) nearby ocean- 55 mg/m(3)

Heron Island GBR lagoon; 850 mg/m(3) nearby ocean- 55 mg/m(3)

(Porter, Moore, Sander, Geptner)


Microzooplankton;

Lizard Island GBR
zooflagellates: 0.1 - 10.0 x 10(5)/l

ciliates: 0.5 - 18 x 10 (3)/l

(Sorokin)


Probably no such thing as "typical" but it is at least a little something to go on. How you measure these in a closed aquaria and compare them is beyond me. :)

Mutagen
01/28/2001, 01:01 AM
JB

THANKS!

When/where did you accumulate this data? Did you find it in the "usual" hobbyist literature?

I'm still not sure I'd agree there is no such thing as typical, even though some of the numbers show a wide range. Its just that there is a wide range. However, if in our aquaria we consistently find numbers an order magnitude higher or lower than the ranges given, then maybe we can begin to find sources for certain problems.

I would assume we could use the same techniques to measure said populations in captive systems as are used in natural systems. Actually, I thought Dr. Ron might have some insight on this subject. It seems to me, it would add some weight to arguments about skimmed vs non skimmed, heavy feeding vs. light feeding, DSB vs. bare bottom, etc. It would also be interesting to track these planktonic concentrations over time in a single captive system. One might expect to see cycle generated by water changes, feeding regimen changes, fish additions, lighting changes and the like. Then finally, we could at least attempt to compare the planktonic water quality parameter to coral responses.

Thanks again JB, Mutagen

saltshop
01/28/2001, 11:12 AM
Mutagen,

Couldn't find any data in the hobbyist literature regarding coral reef ecology so on Dr. Ron's advice I started hitting the University of Michigan library. The bulk of what I could find came from scientific journals, articles submitted to the International Coral Reef Symposia (now ICRcongress) and the book Coral Reef Ecology by Yuri Sorokin. My favorite jounals are probably Coral Reefs, Plankton Research, and Marine Biology FWIW. I am in the process of putting some information about coral feeding behaviors on my web site so I happened to have the numbers above right in front of me. :) Keep in mind those are numbers from a given spot on a particulart reef at a given time so if they were to collect a sample from 10 feet away they would have gotten a different number and likewise if it was done on a different day, but these are at least some place to start. I think it would be safe to say however that the bacterioplankton, phytoplankton, and zooplankton levels over the reefs all exist at much higher levels than in the open ocean, sometimes at levels 2-6 times more.

Mutagen
01/28/2001, 01:16 PM
Hi again JB,

First off, post the URL for your web site. Given the research you are doing for the web site, it sounds like it going to be a good one!

Second, I am about 2 hrs from the Scripps library at UCSD, I was just hoping someone else had already done the leg work. If there is a specific journal you are looking for that U of M doesn't have, I might be able to try Scripps for you.

Third, do the references checked so far give an indication about what type of areas have been tested vis a vis open system, semi open, etc. I don't know much about Lizard Island or some of the other locations tested. Obviously, those listed as lagoon or atoll or open ocean are clear.

Forth, I'll see what I can do about some specific testing in our closed systems. This will no doubt take some time to figure out. I welcome any suggestions on techniques.

Good reefing, mutagen

rshimek
01/28/2001, 02:42 PM
Hi Guys,

Good discussion!!! :D :D :D :D :D :D :D :D

Another thing you have to keep in mind when read these data, is to consider how they are collected.

Many of the earlier studies - say 1990 and before - use larger meshed plankton nets for zooplankton, and have far different values than do some of the later data using smaller meshed nets. There is a signficant mass of microzooplankton (down in the 10- to 100 micrometer range) that is not recorded in those earlier papers. These data have given rise to the myth of no plankton over reefs.

You might check this one out...

Hamner, W. M., M. S. Jones, J. H. Carleton, I. R. Hauri and D. McB. Williams. 1988. Zooplankton, planktivorous fish and water currents on a windward reef face:Great Barrier Reef, Australia. Bulletin of Marine Science. 42:459-479.

The values for bactioplankton and other picoplankton are very dependent upon the sampling method. Different menthodologies can give values that vary as much as 5 orders of magnitude for the same area.

Bottom line - caveat emptor - let the buyer beware, a lot of these data have to be considered in context and are hard to compare one to another.

saltshop
01/28/2001, 02:57 PM
Mutagen,

Once it is completed I will post the URL, hopefully Dr. Ron can check it for me beforehand to make sure I didn't screw anything up. :) It is maybe 50% done so far and could be considered somewhat of a summary of what I have managed to scrounge up. Therefore, it is somewhat simplified as to regurgitate all of the data sets etc. would be way too lengthy.

U of M's library is pretty big so I cannot think of any journals that I am hunting for at the moment since it has all of the "big" ones.

As to your third question, there isn't a whole lot of detail as to the exact locations tested. Lizard Is. is a fringing/barrier reef as far as I know while Heron Is. is a ring reef. Hunt down "Reptillicus" on one of the boards or BMW from ozreef and they can probably give you some good info as to more specifics as far as the GBR is concerned since they live there.

If you want to do some specific testing for reef tanks I would suggest getting with Bob Starks as Dr. Ron mentioned for the bacterioplankton, probably Rob Toonen/biogeek for the phytoplankton counts as he seems to be the resident phyto expert :), and Dr. Ron probably for the zooplankton as he would be my best bet for ID'ing under a microscope. Hope this helps.

saltshop
01/28/2001, 03:16 PM
Hey Doc!

I tried to pick the most recent numbers I could find whenever possible. I noticed the vast differences in collection myself which is why I mentioned that it may vary from day to day. I couldn't believe the older reports that used stationary traps for the zooplankton! I can't believe a group of scientists didn't take into consideration that zooplankton can literally crawl out of the traps or that some would use it as a refuge and give unrealistic higher numbers...DOH! I believe the microzooplankton numbers came from the late 1980s and counted those down to at least 15 microns. (Sorokin 1984, Le Borgne 1989, Blanchet 1989). Thanks for the reference...will find that one next.

rshimek
01/28/2001, 04:15 PM
Hi Saltshop,

A lot of the earlier data were collected biological oceanographers, not by biologists. These folks use the biota to track water masses, for example, and they really aren't concerned about the animals themselves, and sometimes they seem to simply not know about some of the biological properties of the animals.

Keep examing the data critically!!