[Coral-List] Sunscreen, corals, and the usual suspects (Curtis Kruer) and much more.

Gene Shinn eshinn at marine.usf.edu
Sun Dec 9 14:12:46 EST 2007

Curtis, I think we are in agreement. I agree with most everything you 
said. We seem to both recognize that government agencies have rushed 
in and made promises they can not keep. Lots of $$ being 
spent...but...coral continues to die. Its not just the Florida keys. 
Its all over the Caribbean but government and various foundations 
continue to promise that they will save it...yeah! The most effective 
measure to date is installation of mooring buoys and I commend 
everyone involved with that activity.
    I  know many on the people on the Acropora recovery committee and 
realize they are under the gun to do something. Some will admit in 
private that they can do little that is significant. It's unfortunate 
the species was listed without knowing what is killing it and what to 
protect it from. I have become very frustrated with it all. To see 
more questionable use of tax payers money go to the website for the 
Coral Reef Conservation Act meeting advertised in the coral list a 
few days ago. For contrast also look at the comments that were sent 
in as per the Federal Register announcement. They range widely from. 
"do not streamline the permitting process because researchers do 
damage to the reef'" (think stem cell research) to  "we are not doing 
enough research" and one that says "the legal definition of a reef 
could include a thumbnail-sized coral polyp growing on an iron 
(Those are not exact quotes because there is a warning that they 
should not be quoted???) That is all really scary. I suspect that 
some day we will see lawyers enforce that definition of a reef. It 
all boils down to justifying more and more bureaucratic expansion 
that's not likely to save corals.  I think we are all guilty for 
letting it all happen because we overstepped "useful" basic science 
that could of lead us in the right direction. Again I do not 
criticize mooring buoys . On the other hand no research has clearly 
shown that sewage is the major problem (I spent almost 10 years 
trying) or that sediment is the main problem etc. The public just 
wants something done in a hurry and government makes promises while 
we all fall into a bureaucratic malaise. Isn't that the history of 
past civilizations?  Hey am I sounding like an angry old guy?  Guess 
I am.
     Through all this morass of conflicting information what serves as 
my guide, or light in the dark, is reef geology. The proof is in the 
rocks as we like to say in geology. When I was with government we 
spent many years mapping the keys reefs. We core drilled many of 
them. We did Carbon 14 age dating. We did years of seismic surveys to 
map the reefs and sediment thickness. All that information is now 
published and readily available. Also we installed over 100 
water-monitoring wells in the Keys chasing sewage polluted 
groundwater. We did learn that it flows rapidly toward the Atlantic 
where most of the corals reside. That was not known before.  So how 
does it all add up? 
      More than 90 percent of what everyone likes to call a coral reef 
in the Florida Keys is a just a coating of coralline and algal 
limestone ranging between 1 and 3- feet thick and overlain by 20 to 
45 ft of water! We know these areas have been underwater for at least 
6,000 to 7,000 years (since the last ice age) and that the growth 
rate of any of the slow growing species of corals out there could 
have grown right up to the surface in less than 2000 years and that 
the fast growing reef builders (Acropora for example) have the 
potential to have grown hundreds of feet above sea level which of 
course they can not do. Even in this marginal coral area something 
clearly prevented corals for reaching their full potential and that 
was long before modern civilization invaded the Keys. Only a few 
percent of the reefs have kept pace with sea level rise and the rate 
of sea level rise during that period is pretty well known. The few 
reefs that reach the surface are 20 to 45 ft thick and are usually 
the same places where there are lighthouses (put there to protect 
ships). Those are the places where the pretty underwater photographs 
are taken. That's what the public usually sees and that's what we 
would all like to protect. Unfortunately those reefs represent less 
than 2 percent of the entire Keys reef tract! Why?
     Off Ft. Lauderdale in about 50 ft of water there is a very 
extensive topographic feature locally called the 3rd reef. When it 
was living it would have been the most extensive and thickest 
Acropora reef in all of Florida. The Acropora that built it died 
7,000 years ago and sea level continued to rise leaving the dead reef 
behind, complete with spurs and grooves and reef flat, all laid out 
in place. ( see the latest issue of Coral Reefs for a complete 
description). There were no government agencies, foundations, (or 
people for that matter) around to save it.  The truth is we don't 
know what killed it but clearly it was not the usual suspects 
involving humans.
     One of the most revealing observation for me was when I did a 
mission in the Aquarius habitat 14 years ago. We drilled a 50 ft core 
(45 ft of water) in what many would call a reef adjacent to the 
habitat. We picked a flat area to drill so as to avoid the scattered 
100-year-old heads and large sponges. We found that what had 
accumulated there in the past 6 to 7 thousand years was  just 6 
inches thick!! The rest of the underlying core consisted of a soil 
stone-capped Pleistocene reef that had formed more than 80,000 years 
ago. It had been dry land for many thousands of years until about 
7,000 years ago.  A 6-inch coating of reef material (gorgonians, 
algae, sponges, etc.) is what geologists would normally call a hard 
bottom community or more technically a biostrome. That's not a reef! 
No ships, anchors, sewage, etc., prevented that biological community 
from growing up to the surface. So with all that background 
information...and there is much more... I seriously question whether 
the usual suspects have been the major cause of coral demise during 
the past 30 years. Remember the same demise has occurred around tiny 
Caribbean islands where there are very few if any people. Scientists 
at the San Salvador research Lab in the Bahamas watched their 
Acropora thickets die within months in 1983. Diadema died throughout 
the Caribbean at about the same time and diseases affected seafans 
simultaneously. There is just a lot we don't know but the public and 
some scientists keep beating the drums for action and agencies and 
foundations  keep moving in and making promises. They also compete 
with each other for limited funds. Truth is we just don't know what 
has been repeatedly killing corals for the past 6,000 years so how 
can we be so sure we know what has been killing them in the past 30 
       And then there is the experience factor to consider. I grew up 
in the Keys/Miami area and started diving in 1950, I was a 
spearfisherman like most everyone who started diving back then. I did 
my share of damage to the fish population. While diving we seldom saw 
other boats and if we did they were not other divers. Only a few 
crazies did what we were doing. I also worked as a diver on a salvage 
boat...yes we used dynamite to salvage iron ($65 dollars a ton and 
coral encrusted lead and brass up to 35 cents per lb) from turn of 
the century wrecks. Remember corals were healthy and concern for 
coral reefs was still many years in the future. When I stopped doing 
all that around 1960 I began measuring coral growth rates. I can 
honestly say that back then you could stomp, break, and even dynamite 
around live corals and they would began healing in days. A little 
later we documented that hurricanes Donna, and Betsy, devastated 
reefs on a grand scale. They reduced wide expanses of live coral to 
rubble but they came right back! It was not until Hurricane Gilbert 
hit Jamaica in the early 1980s that corals no longer recovered. Its 
been that way throughout the Caribbean ever since. Yes, the 
combination of hurricanes and lobster traps is an especially deadly 
combination. They move all over the place smashing corals as they 
thrash about (also make big holes in turtle grass beds) but they 
still recovered before the late 1970s. Many traps remain on the reefs 
and grass beds long after the season is over. And there are many more 
than in the 1950s through early 1970s. State and federal laws prevent 
anyone or government agencies from removing them.
      Of course fish and lobster grow larger in MPAs but unfortunately 
they do little for the corals. The corals in MPA's just keep on 
dying.  So in conclusion my observation and just about anybody who 
has been diving for more then 40 years in Florida is that the turning 
point came in the late 70s and early 1980s. I have documented this 
coral demise with serial photographs of individual corals starting as 
early as 1959. Corals remain sickly and continue to die and average 
coral cover on the outer reef tract is now under 10%. We still don't 
know why corals continue to die and the research needed to find out 
why is not likely to be funded by those preaching doom and gloom. If 
you have ideas just get out there and do it and then publish your 
     For reasons we do not understand the greatest percentage of 
corals per unit area are on inshore patches in the lower keys where 
visibility is seldom greater than 20 ft and very often less than 5 
ft. How do we explain that?  Isn't continually turbid water supposed 
to kill corals? I agree that anchors and groundings do the reefs no 
good however they are the visible and highly publicized events that 
keep the bureaucracies humming. Sorry I have to sound so negative 
with this rant. I suppose its just what people do when they can look 
back with 20-20 hindsight.  And just think this all started over a 
silly issue about sunscreen and lead diving weights.  Best Wishes and 
happy Holidays, Gene


No Rocks, No Water, No Ecosystem (EAS)
------------------------------------ -----------------------------------
E. A. Shinn, Courtesy Professor
University of South Florida
Marine Science Center (room 204)
140 Seventh Avenue South
St. Petersburg, FL 33701
<eshinn at marine.usf.edu>
Tel 727 553-1158---------------------------------- 

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