Aspergillus and Cheese Sauce, Horge?

[FishDaddy]

This was in the news today and presented an alternative cause for the decline of coral reefs other than pollution and collectors for mad reefers:

SEPTEMBER 22, 15:02 EDT

Dust May Be Killing Coral

By RANDOLPH E. SCHMID
Associated Press Writer

WASHINGTON (AP) — The drought in Africa may be partly to blame for a decline in the coral in the Caribbean Sea, according to a team of
researchers who found coral-damaging fungi in dust blown across the ocean.

``Coincidental with the decline of Caribbean coral reefs over the past 25 years, there has been a sharp increase in the transport of African dust to the western Atlantic,'' reported the team led by Eugene A. Shinn of the U.S. Geological Survey Center for Coastal Geology in St. Petersburg, Fla. With the long-term drought in Africa, combined with overgrazing in many areas, the amount of dust carried across the oceans has been increasing
and is now estimated at several hundred million tons annually.

And the threat may not be limited to corals, Shinn said in a telephone interview.

``We have moved into the realm of public health because the dust is bringing lots of bacteria,'' commented Shinn, who said his research team has now added a microbiologist to study what types of microorganisms
might be carried on the dust.

In 1989 some one-inch grasshoppers from Africa made it to the windward islands in a dust storm. ``If they can make it, think of all the other things that can make it,'' he said.

``Dust often reduces visibility in the Virgin Islands, sometimes causes temporary closing of airports, and is easily verified as African in origin by tracking dust clouds across the Atlantic with ... satellite data,'' the scientists reported.

``Our hypothesis is that some of the decline of the reefs in this region is linked to the increase in dust transport,'' the team said in a paper scheduled to appear in the Oct. 1 issue of Geophysical Research Letters.

Aridity and decertification in northern Africa began increasing in the mid-1960s, worsened in the 1970s and 1980s and then began to lessen in the 1990s.

Major episodes of Caribbean coral mortality occurred in 1983 and 1987, which were also the two years of the greatest dust movement, Shinn pointed out. He said iron and other minerals in the dust affected the water
conditions.

In the mid-1990s an epidemic struck sea fans in the Caribbean and the cause was found to be the soil fungus Aspergillus, the team noted. At the time the presence of Aspergillus was attributed to increased runoff caused by deforestation on Caribbean islands, but outbreaks also occurred
around isolated islands that had no forests.

Shinn's team tested dust samples collected from the air arriving at the Virgin Islands and discovered several species of fungi, including Aspergillus.

``African dust is an efficient substrate for delivering Aspergillus spores;
spores are absent when the air is clear,'' they concluded.

Coral damage, including bleaching of corals, has also been attributed to rising water temperatures and the team agreed that this is probably also a factor.

Shinn will be presenting his conclusions next month at an international conference on coral reefs being held in Bali, Indonesia.

Working with Shinn on the study were rearchers from the University of South Carolina Aiken, University of Miami, University of South Florida, Duke University and the Geological Survey office in the Virgin Islands.

Horge, what are your thoughts on this?
Dick

[horge]

Hiya Dick , thanks for the info.

They certainly found Aspergillus fungus in test cultures made from the infected corals. But I bet cultures taken from healthy corals here in the summer would yield the same, especially with the way some corals ‘farm’ all manner of foreign lifeforms in their mucus as snacks.

Things are even uhmm…”earthier” here in the Philippines. We get four to eight months of dust and then four to eight of mud (that’s summer and rainy season to you foreigners, hehe). During the dry season, wind-borne dust, grit and plant matter can render the water very dirty indeed, not to mention the impressive floating surface-slick/crust that can develop when the summer sea gets too calm to disperse it.

We all know corals are extremely durable, capable of exposure to a wide range of temperatures, salinities, even brief siltation, and I agree that the hobby has unfairly been made a scapegoat for reef decline. Ditto boat anchors and such.

IMO it takes a severe combination of unfavorable climate, man-made pollution, and intentional abuse to kill a reef. Some studies suggest that periodic catastrophe is vital to reef’s health, as it ensures a fresh start for all. Dominance by only a few species renders the whole reef less biodiverse and thus less resilient in the face of (less frequent) disasters. There is also the healthy, general toughening of reef organisms when faced with regular, milder, environmental onslaughts.

**This touches on an issue I have with reefkeeping today: Everyone is focusing on static ideals, like the “optimum temp.” or the “optimum lighting intensity”, pegging their tanks to those rigid values.

Lord only knows what stimuli are missing, via the periodic (daily/monthly/annual/triennial, etc.) cycles of variation in params, --like the incredible drops in salinity, temp and available light during the rainy season. What about water motion? Without the proper stimuli, it is no wonder that reports of in-tank spawning of corals and anemones (and I mean true spawning, not cloning or self-fragging) are very uncommon. But I digress!

Sure, dust will affect corals, and sure reefs will (nearly) die off. But unless things are totally out of whack, they will rebound and stronger for the stress. Our reeftanks might be operated on the same principle.

Again, thanks for the info


Horge

PS:
Personally, while I make sure my corals are (randomly) well fed/lighted, I allow them to get some ‘exercise’ via judicious application of simulated environmental stress, hehe*, to toughen them. Just my crazy personal approach for the past decade or so. Of course, I baby them when they’re new arrivals….

Two months ago I came home from the US and found my corals in semi-stagnant, brackish, nearly fresh water, because the rain had breached the ‘roof’ over my basins and the powerhead had partially clogged.

I gently corrected the salinity, and the corals look none the worse for wear.

[FishDaddy]

Thanks, Horge, I knew you would have insight into this. There are so many external influences, natural and manmade, on all our eco-systems that it would seem to make it very difficult to isolate specific causes and results. I always think about the conclusions or assumptions that can be drawn from the presence of Iodine in coral skeletons. You could surmise that a) corals need Iodine; b) Iodine is simply present in all organisms or even c) Iodine kills corals!
It really is interesting to see the efforts some make for perfect aquarium conditions(thats not necessarily a bad thing) but does sometimes lead to over-reacting when a parameter changes.
Those of us who have been blessed with the opportunity to dive on actual reefs know that the sea is certainly not a static environment and attempts to duplicate it exactly would probably need application of chaos principles! The old axiom that "nature doesn't make straight lines" does have relevance as you just can't straight line the chemistry and environment of a tank since the living organisms, light and other processes will cause changes of their own. I suppose the ability of one coral specimen to rebound over another is nature's way of ensuring the survival of the fittest since the dead ones don't breed.
These are just ramblings but illustrate that we have only scratched the surface of reef knowledge and that I am glad there are folks like you who are still doing some scratching!
Dick

[RWD]

I also have to agree that MODERATE fluctuations in salinity, temperature, etc are actually good for corals. I believe that corals are like plants in that these fluctuations "harden" or "temper" the corals. This makes them more resiliant in my opinion. Something I learned from gardening is that if you slowly adapt your plants to the more extreme temps, they become more hardy. Like Horge said, Don't get caught up in the numbers. How does your tank LOOK. Bob

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Check out my new web page: http://bobsreefermadness.homestead.com/index.html

[Martyn]

Thanks Dick for bringing this thread up and your thoughts
Horge this is not the first time I have read your views on this.
I really am interested in your views you always get me thinking and this is something I have been thinking about for some time now.
Am I on the right track here and a few questions.
Roughly what months of the year are the rainy season?
In the rainy season does the salinity become lower and temperatures drop and trace elements become lower as well as the lower light available does sea levels rise during the rainy season?.
And what months are the dry seasons?
I presume the reverse is true for the dry season.
Oxygen change at different times during the day and I presume seasons weather etc
Do you have a hurricane or typhoon season
Then you have the moon cycle does this and the seasons have anything to do with mass spawning.
Do you have fluxes in plankton levels.
Don't you think algae's play a larger role in our reefs than is mentioned
Questions questions I should not be so lazy and read up more In fact I will study this more.
Martyn

[horge]

Martyn: The rainy season starts as early as July and extends sometimes into December. The best time to snorkel the reefs is March-April if you're after warmth, or December if you're after water clarity and calmer waves.

RWD: Bob, when do we get to see that 300 gallon of yours? :-)

Doug: I agree the hobby is an easy target.
The "aragonite" sold in the hobby supposedly comes mostly from naturally disintegrated skeleta of fasty-growing ramose corals. Someone (Palpalatoc?) once estimated the output of a 2 square-kilometer pocket reef here at 0.3 metric tons per year (I would have preferred a volume estimate, which would be easier to compare to hobbyist per-capita consumption).

Because each reef is unique, nobody knows how miuch dead skeleta can be harvested before you take a chunk out of reef growth, beach formation, or 'live rock' formation..

Live rock is a similar issue: you are taking out a part of the reef that might otherwise have been colonized by coral planulae and/or made refuge by fish or invert. That stuff is gold, folks, so make the most of it.

[RWD]

Hey Horge,
Here you go:


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Check out my new web page: http://bobsreefermadness.homestead.com/index.html

Wow another great thread, nice to see something other than the typical gloom and doom blaming me for the decline of the reefs.It seems that most people forget as they are reading the latest disaster predictions that nature isnt static, its in a constant state of flux. There have been radical cycles in climate and all sorts of other variables. Not to diminish the destructive influence but think about aragonite we are so fond of in our reef tanks. This is mined from fossilized reefs, is it not? I seriously doubt that the early forerunners to Homo sapiens over collected and ruined the reefs. You gotta love this hobby, the more you learn the more you wanna learn

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I thought I was me, but I was wrong

[horge]

Horge: "Anak ng tokwa!!!"
Dark Horge: "Wow!!!"
Horge's wife: "ANG GANDA!!!"

[Translation from Filipino:
"Son of a stir-fried beancurd!!!"
"Wow!!!"
"Just gorgeous!!!"]

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Bob, I just might pass through Chicago next year, and I can be a most persistent, uninvited guest.
Anybody else on TRT wanna crash Bob's house?
Mwahahahaha!!!!!

Be afraid.
Be very afraid!!!



[This message has been edited by horge (edited 09-24-2000).]

[RWD]

Horge,
Thanks for the compliment, I think (stir-fried bean curd???).You know you are more than welcome. Maybe another road trip is in order with a pit stop at HOOters. Bob

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Check out my new web page: http://bobsreefermadness.homestead.com/index.html

[Alice]

Very nice, Bob! Thank you

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Reefkeeping is my life; I can't afford a hobby too!

WOW OK anyone want a little bitty 75 predrilled AGA, I need a BIG TANK
Thanks Bob thats awesome, Horge stop by and get me on the way, hehehehe

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I thought I was me, but I was wrong

[RWD]

Hey guy's,
Thanks for the kind words. Can I have a few opinions about the lighting. All my previous tank have been vho and I loved the color. This is my first try with mh. The tank has 3 400 watt 6500k Iwasaki's and 2 6' URI actinic vho's. Although the color isn't bad, it just dosen't look as good as my other tank (125 gal with 6 vho; 2actinic and 4 50/50)I would like to stay with the 6500k's for now because they are supposed to be great for the corals. I was thinking of adding 4 24" vho actinics to get a little more blue light. I would go with the 24" bulbs because I want to keep access open to the tank. Is it me or does the tank look too yellow? Bob
ps Moderators,
Fell free to move my question or I can if you want me to. Bob

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Check out my new web page: http://bobsreefermadness.homestead.com/index.html

[FishDaddy]

AWESOME BOB!!!
Dick