Flower Gardens Update

EricHugo at aol.com EricHugo at aol.com
Sun Aug 15 21:52:03 EDT 1999

Hello all:

My recent trip to the Flower Gardens/Stetson Banks was an overwhelmingly 
positive experience.  It has been a long time since I have seen such a 
healthy reef system in Gulf/Caribbean waters. 

Flower Gardens:  East and West Banks, both reported to be on Mooring #5 at 
each reef site

There were many juveniles present of fish, corals and other invertebrates, 
and these seem well balanced by healthy populations of predators.  There were 
fairly good populations of Diadema urchins, with many spawning during the 
night dive at approximately 2100 to 2200 hours (near new moon).  The water 
temperature was 87F at the surface and approximately 84-85F at 70-90 feet of 
depth. Surface conditions were swells from 2-4 ft and no noticeable currents 
at depth during any of the dives. Bleaching was not seen on any corals, with 
the possible exception of a very large head of Montastrea annularis.  This 
particular colony had a broad flat top over five feet across and continued 
down vertically for another 4-5 feet.    The top surface of this coral was 
noticeably more light golden colored than the bottom margins, and upper sides 
became uniformly more lightened towards the upper surface.  Whether this was 
a partial bleaching or just different clades of zooxanthellae and 
photoacclimation is questionable, but it was more notably light than similar 
sized colonies on its upper surface.

Disease:  The whitened areas of parrot fish bites were obvious.  However, I 
noted a total of four corals that appeared to have WBD or a similar white 
syndrome.  West Bank had two of these colonies:  A Diploria sp. immediately 
at the base of the mooring line attachment had a uniform white band from its 
lower margins extending up approximately 1- 2"  around its circumference.  I 
found it notable that this coral happened to be at a point where it could be 
encountering repeated stresses from divers descending the mooring line.  The 
other coral with a WBD-type occurrence was tentatively identified as Madracis 
pharensis forma luciphilia. I am not confident in this identification, 
however, as my hand lens wasn't with me on this dive.  This coral had been 
injured near its lower margin, evidenced by a chunk that was missing, and it 
did not appear to be from a bite.  From this area, a white band had begun to 
partially encircle the rest of the base, but had not made a complete 
circumference yet.  The band was approximately 2-3" wide tapering off to 
healthy coral tissue some distance away.  On the East Bank, 2 Diploria sp. 
had WBD-type signs, again both adjacent to or very near the mooring 
attachment site.  East Bank also had numerous places where bare zones between 
competing corals (mostly M. annularis and Diploria sp.) had significant 
cyanobacterial accumulations. These accumulations seemed more dense than 
those on interacting corals on the West Bank. In a single case observed, the 
accumulation was quite localized near the Diploria margin and could, in my 
estimate, form a BBD in the future. No visible black consortium material was 
present yet, although the cyanobacterial mat was denser and darker than those 
present in similar competitive interactions.  No other unusual or unhealthy 
conditions were seen at either site.

A Young Ridley's sea turtle was seen at the surface while on deck grazing 
through a small patch of Sargassum.  No other sea turtles were seen by the 
group.  Two black tip reef sharks were seen at 1800 hours. No reports of 
other elasmobranchs.  

Stetson Bank:

Shouldn't the name be changed to Millepora Bank?  Heavy fish populations and 
very heavy Millepora coverage. No bleaching or disease noticed on any of the 
sparse corals covering the area.  Dictyota growth on the flats was moderate 
but not overgrowing the Madracis sp. or other isolated coral heads present. 
Some fireworms seen grazing on Millepora at 0700 hours.  One large spotted 
eagle ray was seen at 1030 hours. Fairly turbid green water with moderate 
currents at depth and a pronounced 5-7F thermocline at approximately 40 feet 
from the surface. 

For those who made specific requests for photos and specific reports, I will 
forward the pictures and reply directly as soon as they are developed.  I did 
not locate M. asperula on any of my dives. 

Eric Borneman 

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