[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
bulkhead!!"
(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
years?
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
results.
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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