[Coral-List] Coral killing continues in Florida

Eugene Shinn eugeneshinn at mail.usf.edu
Tue Sep 15 12:46:12 EDT 2015

I suppose no amount of apologizing will undo the wrath generated from 
coral biologists about my comments concerning Sarah’s comments regarding 
Miami ship channel dredging. (Supportive letters offline however did 
salve my ego a little)I would be the first to agree that dredging is 
never a pretty sight.

I do appreciate the comments of Andrew Baker. His comments reflect a 
biological perspective/bias while mine are more geologically biased. I 
have not personally visited the Government cut area during the recent 
dredging but have talked with scientists involved in monitoring, 
transplanting and mitigation related to the project. I was also unaware 
of Great Lakes using draglines and loading of dredge spoil on 
barges/scows. I had assumed they were doing only conventional suction 
dredging with cutter heads and piping spoil offshore similar to what 
they did during the earlier deepening of government cut in the early 1970s.

My association with the area goes back to high school days. I learned to 
dive and spear fish off the north Jetty. (I used homemade flippers made 
from truck inner tubes because I could not afford the Owen Churchill 
flippers that had just come on the market)During my UM years 1953-1957, 
I built a 14 ft. Chris-Craft kit boat that I used for spearfishing the 
entire Government cut area out to what we called the third reef.There 
were enough fish and lobster then to keep my growing family fed. I 
continued that activity for a year following graduation while working as 
a low paid technician at the U. of Miami Marine Lab (Now RSMAS). During 
that year I also photographed experimental mines and the bottoms of 
destroyers off Ft. Lauderdale for the Navy. Later I was fortunate enough 
to land a job, with a livable salary, when I was hired by Dr. Robert 
Ginsburg who operated a small geological research lab in Coral Gables 
funded by Shell Development Co. My original training at U of Miami was 
biology but under Ginsburg’s guidance, several assignments in Texas, and 
because of self-funded coral reef studies and other publications (one of 
which won the annual best paper award) I was promoted to geologist. My 
specialty and publications then were on modern and ancient reefs as well 
as tidal flats. (Ancient analogues of those environments produce oil 
worldwide so understanding distribution, how to recognize them, 
thickness and geometry of modern examples was useful to other geologists 
exploring similar subsurface formations millions of years old). That 
conversion to geology and stratigraphy (I liked to call it geo biology) 
led to 3-years conducting similar research and diving in the Persian 
Gulf.I left Shell after 15-years and a final 2-years wearing a 3-piece 
suit as Staff Biologist in their Houston head office. We were hated by 
anti oil environmentalists (little has changed since then). It was 
disheartening to realize that what many really wanted was funding for 
their pet projects. (In later life I have seen that motive repeated over 
and over in various fields of endeavor.) I left the company in 1974 to 
set up a USGS field station on Fisher Island and get back to doing 
geo/biological research. Our office over looked Government Cut. (We 
worked there 15-years). Our first priority was to develop an underwater 
coring device pattered after the one pioneered by Walter Adey and Ian 
Macintyre.During the early years at Fisher Island we dove in the sewer 
trench that was cut through the outermost dead reef off Ft. Lauderdale, 
monitored dredging effects of beach nourishment off north Miami beach, 
and measured sections in the trench dug for extending the Virginia Key 
sewer pipe out to its present location. These excavations provided 
valuable views into the interior composition reefs in those areas. Those 
observations made it abundantly clear those reefs had been constructed 
by /Acropora palmata/ but were no longer growing. Carbon 14 age dating 
showed the outer most reefs had died around 7,000 years ago. Many reef 
workers know that Vaughan published in 1917 that reef development ended 
north of Fowey reef.Of course there were scattered corals of various 
species on the surface but they were no longer building the reef. The 
Fisher Island location also allowed us to observe the operations of 
Great Lakes dredging company when they first deepened the Miami ship 
channel. Their suction dredge vessel sucked up a piece of iron that 
damaged the vessel causing it to sink in the channel opposite the 
present day cruise ship port. There was little concern over those 
dredging activities back then. The environmental movement was still in 
its infancy in Florida while in California activists were chaining 
themselves to trees.

At that time no one was studying coral diseases and genomic studies of 
corals was unheard of. The new concept that those hardy species that 
survived prior dredging and other threats may pass on their resistant 
genes for future growth in tainted environments is a new and interesting 
field. I assume this possibility applies to most all survivors of 
declining reefs throughout the Florida Keys.

I would like to point out that our seismic and core-drilling studies 
indicated there were earlier die-offs of coral reefs that predated human 
occupations. Our published 14C study of fossil A. /cervicornis/ (A 
/cerviconis/ and /palmata/ are now threatened species) indicated it was 
absent for a 500 year period centered around 4.5ka and later there was 
one centered around 3ka. Furthermore, extensive coring indicated they 
never lived in much of what became classified as “critical habitat” 
areas, especially those areas West of Key West Florida.

Furthermore, many reef workers remember that both species of /Acropora/ 
began to die in the late 1970s culminating in 1983 when rapid demise 
occurred throughout the Caribbean. During the same year the urchin 
/Diadema/ experienced near extension throughout the Caribbean. Our most 
surprising discovery resulting from Keys wide seismic mapping, and 
coring was that coral accumulation thickness in more than 90 percent of 
the so-called reef-tract is no more than 2 meters. That the Keys reef 
tract has been underwater because of rising sea level for around 6,000 
years verify that there have been previous periods of reef demise of 
Florida corals. In addition our 49-foot core of Pleistocene coral 
drilled adjacent to the Aquarius underwater habitat revealed about 6 
inches of accumulation during the past 6,000 years. What looks like a 
coral reef to biologists is simply a hard bottom coral and sponge 
community.Can the numerous biological studies conducted from the habitat 
explain why so little coral accumulation has taken place there during 
the past 6,000 years? These are important questions that beg for 
answers. I would like to say more but all of this and more is  
documented in our upcoming book, “Key Limes” coauthored by Barbara Lidz. 
Finally I still emphasize that one year after this dredging ends the 
casual diver will not notice any changes in the areas adjacent to the 
deepened channel.

However who knows what effect the giant ships that will pass through may 
have on the city of Miami? Gene


No Rocks, No Water, No Ecosystem (EAS)
------------------------------------ -----------------------------------
E. A. Shinn, Courtesy Professor
University of South Florida
College of Marine Science Room 221A
140 Seventh Avenue South
St. Petersburg, FL 33701
<eugeneshinn at mail.usf.edu>
Tel 727 553-1158
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