Divers Jules Craynock and Derek Manzello inspected DBJM1 on Sept.11, 2007. Pin# 8 showed cracked substrate and concrete exposing 25% of the upper pin body. The T- pin was movable in bending toward the pylon, but not twisting. An approximate 5 degree listing of the pylon occurs, opposite pin 8 in a SE direction. All lashings and legs are in good condition and the installation is stable for normal conditions. Pin 1 showed slight upper substrate cracks but is sturdy. On Sept. 12, 2 qts. of 2-part u/w epoxy were applied to Pin 8 to rebuild the cracked substrate and the repair appears to have stopped the bending movement. The leg to pin 8 will have to be retensioned in the future and the behavior of the repaired pin under the tension needed to right the pylon is uncertain. No twisting of the pylon had occurred while exposed to the heavy forces of Hurricane Dean/Category 1.
Jules Craynock
This site is for providing Discovery Bay, Jamaica the CARICOM/World Bank/MACC/NOAA ICON/CREWS Station maintenance records for data management purposes. Please update this blog whenever new operations are performed in the field, so that NOAA/AOML can coordinate their efforts with the Discovery Bay ICON/CREWS station field efforts.
Sunday, September 16, 2007
Friday, September 14, 2007
Field Trip Completed
A team from AOML was at DBJM1 during the week of September 10th - 14th. The team consisted of Jules Craynock, Derek Manzello, Lew Gramer and Mike Jankulak.
Aerial work completed: the Vaisala Weather station mounting was adjusted by approximately nine degrees. The five solar panel cables were significantly shortened. The failing windbird / electronic compass combination was removed from the station and its aluminum mast put into storage. The station "brain" was removed and replaced; the logger firmware was upgraded on land and the internal barometer replaced. The barometer air tube was found to be filled with water at the outside end; this tube was removed. No damage of any kind (from Hurricane Dean) was observed above the surface. Four aluminum rungs were bent during station work but there are enough spare rungs to cover this loss.
Underwater work included adding 2-part epoxy to stabilize pin #8. Various maintenance tasks and biological survey activities were also performed (details to follow). The Groundtruth CT was connected during brain replacement to ensure that all connections were correct.
Future work: another trip will need to be scheduled to install the station "stabilization collar" and the replacement windbird and electronic compass.
-- Mike J+
Aerial work completed: the Vaisala Weather station mounting was adjusted by approximately nine degrees. The five solar panel cables were significantly shortened. The failing windbird / electronic compass combination was removed from the station and its aluminum mast put into storage. The station "brain" was removed and replaced; the logger firmware was upgraded on land and the internal barometer replaced. The barometer air tube was found to be filled with water at the outside end; this tube was removed. No damage of any kind (from Hurricane Dean) was observed above the surface. Four aluminum rungs were bent during station work but there are enough spare rungs to cover this loss.
Underwater work included adding 2-part epoxy to stabilize pin #8. Various maintenance tasks and biological survey activities were also performed (details to follow). The Groundtruth CT was connected during brain replacement to ensure that all connections were correct.
Future work: another trip will need to be scheduled to install the station "stabilization collar" and the replacement windbird and electronic compass.
-- Mike J+
Thursday, September 13, 2007
NO bleaching
I forgot to mention in my recent post that I observed little to no bleaching. There are some anecdotal reports of Agaricids starting to pale and/or bleach in deep water, but we were unable to observe this. Nevertheless, this sounds similar to the deep paling and partial bleaching of the plating Agaricids I saw in St. Croix two weeks ago. In short, nothing to write home about on the bleaching front.
FYI..in my previous post I mention the acronym YBD without defining it. YBD = Yellow Band Disease.
Cheerio,
Derek
FYI..in my previous post I mention the acronym YBD without defining it. YBD = Yellow Band Disease.
Cheerio,
Derek
Biological monitoring
Video transect surveys and urchin counts were performed today by Hugh Small, Camilo Trench, and myself. Fifteen video transects were run (16 m length transect line). All urchins within 0.5 m on either side of the transect line were identified and counted. A total of 20 urchin count transects were run (16 square meters per transect). Diadema antillarum is locally abundant near the ICON site and was the most abundant urchin surveyed. This is very encouraging as algal biomass is significantly reduced around the grazing area of individuals and where D. antillarum is absent, algal biomass is incredible (thats a scientific term).
I noted several large Acropora palmata pieces (up to 1 m in max. diameter) that had been broken and transported behind the reef crest during Hurricane Dean. Other than this, there were no indications of any negative hurricane impacts.
Nineteen colonies of Montastraea faveolata were tagged and photographed. Photos should be re-taken in 3 months to assess mortality and recovery. YBD appears to only be affecting a small proportion of M. faveolata colonies, but diseased colonies appear to have a clumped distribution. Colonies were tagged because YBD seems to be occurring throughout the Caribbean at the present time. I have received confirmed reports of YBD in the Dominican Republic and U.S. Virgin Islands to date. YBD appears to have been more abundant at the St. Croix site.
I would like to extend my utmost gratitude for the field support provided by Hugh and Camilo and to our captain Anthony.
Best regards,
Derek Manzello
I noted several large Acropora palmata pieces (up to 1 m in max. diameter) that had been broken and transported behind the reef crest during Hurricane Dean. Other than this, there were no indications of any negative hurricane impacts.
Nineteen colonies of Montastraea faveolata were tagged and photographed. Photos should be re-taken in 3 months to assess mortality and recovery. YBD appears to only be affecting a small proportion of M. faveolata colonies, but diseased colonies appear to have a clumped distribution. Colonies were tagged because YBD seems to be occurring throughout the Caribbean at the present time. I have received confirmed reports of YBD in the Dominican Republic and U.S. Virgin Islands to date. YBD appears to have been more abundant at the St. Croix site.
I would like to extend my utmost gratitude for the field support provided by Hugh and Camilo and to our captain Anthony.
Best regards,
Derek Manzello
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