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SITE  SUMMARY         58     Site  Summaries   RATIONALE   The  purpose  of  this  section  is  to  provide  a  more  comprehensive  survey  of  TCRMP  site   characteristics  than  can  be  achieved  in  the  overall  data  compilations.    Each  TCRMP   monitoring  site  is  each  unique  and  has  experienced  unique  responses  to  local  and  global   stressors.    Given  the  increase  in  sites  included  under  this  program  and  the  inclusion  of   more  information  at  each  site,  such  as  physical  data,  this  section  is  designed  to  provide  a   summary  that  highlights  the  each  site’s  characteristics  and  serves  as  a  quick  reference   guide  for  managers,  policy  makers,  and  academics.    The  duration  of  surveys  at  most  sites   also  now  provides  sufficient  data  from  which  to  draw  conclusions  about  longer  term  site   dynamics  and  the  processes  that  might  be  contributing  to  recent  trajectories  of  health,   development,  and  degradation.     SITE  SUMMMARY  ELEMENTS   TCRMP  site  information  is  presented  in  six  pages  that  provide  a  brief  description  of  the   setting  and  the  potential  susceptibility  to  local  and  global  stressors  and  disturbances.    Sub-­‐ sections  include  a  description  of  (1)  the  physical  environment,  (2)  the  benthic  community   and  (3)  the  fish  community.    The  benthic  data  and  coral  health  are  updated  in  each  annual   report,  whereas  the  fish  summaries  and  physical  data  are  updated  periodically.   Benthic  community  structure  is  presented  as  the  mean  (±SE)  cover  of  coral,  macroalgae,   cyanobacteria,  and  epilithic  algae.    Epilithic  algal  communities  are  diminutive  turf  and   filamentous  algae  that  cover  hardbottom  surfaces,  whilst  macroalgae  have  identifiable   thallus  differentiation  and  structure.    Any  open  hardbottom  space  is  assumed  to  host  an   epilithic  algal  community  even  if  algae  cannot  be  resolved  in  video  images.    The  loss  of  coral   cover  due  to  the  2005  bleaching  event  was  calculated  as  the  relative  change  in  coral  cover   from  2005  to  2007,  unless  otherwise  noted  for  sites  not  sampled  in  these  years.    In   addition,  the  percent  recovery  from  the  2005  bleaching  event  was  calculated  as  the  amount   of  coral  cover  regained  by  2011  (Cover2011  -­‐  Cover2007)/(Cover2005-­‐  Cover2007).    Change   calculations  must  be  treated  with  caution  for  sites  where  transects  where  not  made   SITE  SUMMARIES       59   permanent  until  after  the  2005  bleaching  event  or  where  percent  cover  is  low,  since  the   conditions  introduce  an  unknown  amount  of  error.   Benthic  community  pie  charts  were  constructed  from  all  years  of  data.    The  sessile   epibenthic  animal  community  includes  Agaricia  spp.,  Colpophyllia  natans,  Diploria  strigosa,   Orbicella1  spp.  (O.  faveolata,  O.  fransksi,  +  unidentified  Orbicella  spp.),  Orbicella  annularis,   Montastraea  cavernosa,  Porites  astreoides,  branching  Porites  species,  Siderastrea  siderea,   other  corals,  sponges,  gorgonians.    The  algae/non-­‐living  substrata  category  includes   cyanobacteria,  epilithic  algae  (“DCA”),  Lobophora  variegata,  Dictyota  spp.,  Halimeda  spp.   crustose  coralline  algae,  and  sand/sediment.   Coral  Health  is  presented  as  the  mean  (±SE)  of  coral  bleaching  prevalence  (proportion  of   population  affected)  and  extent  (proportion  of  colony  affected),  disease  prevalence,  and   partial  mortality  prevalence.   PHYSICAL  CHARACTERISTICS.       Temperature.    Benthic   temperatures  were  recorded  at   each  site  with  a  HoboTemp™   thermistor  data  logger  (Onset   Computer  Corporation,  Bourne,  Massachusetts).    Thermistors   were  affixed  within  transects  and  set  to  record  at  intervals  of  15   minutes.    Records  are  presented  as  daily  averages  across  months,   February  29th  excluded.    Each  temperature  figure  includes  the   climatological  monthly  maximum  mean  temperature  (28.5°C),   and  the  bleaching  threshold  temperature  (29.5°C)  established   for  the  region  (NOAA  2006).    Data  for  2005  was  taken  from   current  profilers  or  federal  data  sources.   Currents.    Water  currents  were  recorded  at  a  subset  of  sites  and                                                                                                                   1  The  genus  Orbicella  was  formerly  named  Montastraea,  but  changed  in  2012  reflecting  an  earlier  precedence   and  dissimilarity  with  Montastraea  cavernosa  (Budd  et  al.  2012).    Some  figures  in  this  report  may  still   abbreviate  the  genus  name  as  “M.”   SITE  SUMMARY         60     times  with  Nortek  Aquadopp™  Acoustic  Doppler  Current  Profilers  (ADCPs).    Profilers  were   set  in  bases  on  the  seafloor  and  set  to  record  current  speed  and  direction  within  predefined   depth  bins  above  the  substrate.    The  bin  closest  to  the  substrate  and  closest  to  the  coral  reef   was  selected  for  display.    Compass  rose  figures  were  developed  that  show  the  frequency  of   current  in  magnetic  directions  0,  22.5,  45,  67.5,  90,  112.5,  135,  157.5,  180,  202.5,  225,   247.5,  270,  292.5,  315,  337.5,  360°.    Within  each  direction  the  frequency  of  current  speed   within  bins  of  0.1  m  s-­‐1  were  plotted.  For  Flat  Cay,  current  data  was  retrieved  with  an   Aandaraa  2-­‐D  current  meter  that  measured  current  speed  and  direction  directly  over  the   sensor  head.   Chlorophyll  and  Turbidity.  Continuous  fluorometric  measurements  of  chlorophyll  and   turbidity  were  conducted  at  some  sites  for  short  periods  (Black  Point,  Grammanik,  Magens   Bay).    Wetlabs  ECOFLNT  fluorometers  with  antifouling  bio-­‐wipers  were  deployed  and  set  to   record  for  one  minute  at  hourly  intervals.    Water  column  chlorophyll  measurements  detect   phytoplankton  abundance.      Fluorometric  measurements  of  chlorophyll  are  proxies  for  true   chlorophyll  concentrations.    Direct  chlorophyll  measurements  to  calibrate  fluorometric   measurements  have  not  been  conducted  at  the  monitoring  sites. SITE  SUMMARIES       167   St.  Thomas     SITE  SUMMARIES       169   BLACK  POINT   Descrip(on.    Black  Point  is  a  nearshore   fringing  reef  located  at  the  mouth  of   Brewers  Bay  along  the  southwest  coast   of  St.  Thomas  in  water  depths  of  7  –  17   m.    The  reef  has  a  sharp  break  in  slope   leading  to  a  steep  escarpment  that   terminates  in  a  sediment  plain  at  the   reef  base.    Black  Point  appears  to  be  a   true  reef  with  a  well-­‐developed   carbonate  framework  over  bedrock.     Black  Point  has  been  monitored  since   2003,  with  permanent  benthic  transects   installed  in  2007.    A  ciguatera  fish   poisoning  study  with  monthly  sampling   has  been  ongoing  since  2009.   Outstanding  Feature.    Black  Point  supports  a  fish  spawning  aggregation  of  striped  parrotfish   (Scarus  iserti)  with  afternoon  mating  at  the  edge  of  the  upper  reef  break.   Threats.    Brewers  Bay  subjected  to  land-­‐based  sources  of  pollution  and  tends  to  have  turbid   water  and  overgrowth  by   heterotrophic  organisms,  such  as   sponges.    Recreational/artisanal   fishers  with  handline  and  spear   frequently  fish  this  site.     Figure  97.    Black  Point.  (top)   Location.    (right)  A  representative   photo  of  the  reef.       BLACK  POINT         170   Figure  98.    Black  point  current  speed  and  benthic  temperature  record  (8  m  depth).   Physical  Characteris.cs.    Current.    Black  Point  has  restricted  water  flow  dominated  by  weak   currents  running  counter  or  orthogonally  to  the  left  of  the  dominant  wind  direction.    This   may  indicate  that  there  is  a  counter  flowing  eddy  from  Perseverance  Bay  to  the  west  that   impinges  on  the  headland.    Current  data  are  based  on  average  data  taken  every  30  min.   (11/29/06  to  3/1/2007)  and  hourly  (4/19/07  to  9/5/07).    Temperature.    Black  Point  has   low  circulation  and  relatively  high  mean  temperatures  with  very  low  day-­‐to-­‐day  variability.     Chlorophyll  &  Turbidity.    Chlorophyll  tends  to  be  high  at  Black  Point,  likely  due  to  inputs   of  land-­‐based  nutrients  that  fuel  pelagic  productivity.    There  are  also  exists  a  very   prominent  tidal  signature  that  reflects  switching  source  currents  at  the  reef.   Figure  99.    Black  Point  chlorophyll  (left)  and  turbidity  (right)  record  (16  m  depth)     N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW Current Speed (m s -1) 0.5 - 0.6 0.4 - 0.5 0.3 - 0.4 0.2 - 0.3 0.1 - 0.2 0.0 - 0.1 Nov 2 Nov 5 Nov 8 Nov 11 Nov 14 0 2 4 6 8 10 12 14 16 18 20 Turbidity (NTU) 2006 Nov 2 Nov 5 Nov 8 Nov 11 Nov 14 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Chlorophyll (µg L -1) 2006 J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2005 2006 2009 2007 2010 2008 2011 Temperature ( oC) Month SITE  SUMMARIES       171     Benthic  Community.  Black  Point  supports  a  very  diverse  coral  community  with  very  equal   representation  by  many  coral  species.    However,  large  colonies  (>  100  cm  diameter)  of   Orbicella  annularis  and  Orbicella  faveolata  occur  on  the  eastern  edge  of  the  site,  with  a  few   occurring  within  transects.      This  coral  community  lost  40.5%  of  its  coral  cover  in  the  2005   bleaching  event;  however,  by  2011  it  had  regained  103.5%  of  its  coral  cover.    The  algal   community  at  Black  Point  is  co-­‐dominated  by  epilithic  algae  and  the  macroalga  Dictyota   spp..   Coral  Health.    Black  point  corals  were  severely  affected  during  the  2005  bleaching  event   with  nearly  all  colonies  bleached  over  100%  of  the  colony  surface.    The  prevalence  of  coral   diseases  was  moderate  with  dark  spots  disease  predominating.    However,  white  disease   outbreaks  occurred  at  least  twice  over  the  sampling  period.    Old  partial  mortality  became   very  prevalent  after  the  2005  coral  bleaching  event  and  subsided  in  the  following  two   years.     Figure  100.    Black  Point.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   BLACK  POINT         172   Figure  101.    Black  Point  benthic  cover  and  coral  health  through  time  (mean  ±SE).       Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES       173   Fish  Community.    Black  Point  is  highly  dominated  by  herbivores.    Juvenile  parrotfish  and   damselfish  are  numerous.    Brown  chromis  are  equally  abundant.    The  site  is  turbid  and   holds  very  few  large  fish,  although  the  occasional  cubera  snapper,  Nassau  grouper,  and   yellowfin  grouper  are  spotted,  a  rarity  for  nearshore  areas  of  the  USVI.    A  resident  mutton   snapper  is  regularly  observed  cruising  the  sand  line  at  the  bottom  of  the  reef.  Hamlets  are   diverse  and  common.    The  black  hamlet  is  especially  abundant  among  the  hamlets.    In  the   mid  to  late  afternoon  striped  parrotfish  (Scarus  iserti)  spawn  at  Black  Point.    They  can  be   seen  swimming  along  the  reef  edge  in  large  groups  beginning  in  the  early  afternoon.     Spawning  goes  in  to  the  late  afternoon  and  involves  tens  of  fish.    Black  Point  is  close  to   shore  and  is  not  trapped  often;  however,  divers  can  swim  to  the  reef  from  the  beach  to   spearfish.  It  is  notably  absent  of  resident  large  edible  fish.       BLACK  POINT         174   Figure  102.    The  Black  Point  fish  community  by  absolute  and  relative  biomass. Herbivores striped parrotfish stoplight parrotfish redband parrotfish threespot damsel princess parrotfish dusky damsel blue tang Beaugregory queen parrotfish doctorfish cocoa damsel bucktooth parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 12000 Invertivores creole wrasse yellowtail snapper brown chromis blue chromis tobaccofish bicolor damsel Fish Biomass (g) 0 5000 10000 15000 20000 25000 Planktivores spotted goatfish French grunt tomtate spotted drum squirrelfish yellowhead wrasse Spanish hogfish butter hamlet shy hamlet yellowbelly hamlet yellowtail hamlet indigo hamlet harlequin bass slippery dick rainbow wrasse clown wrasse Fish Biomass (g) 0 500 1000 1500 2000 2500 Piscivores graysby glasseye snapper bar jack red lionfish black hamlet trumpetfish Fish Biomass (g) 0 200 400 600 800 1000 1200 1400 1600 1800 SITE  SUMMARIES       175   BOTANY  BAY   Descrip(on.    The  Botany  Bay  site  is   located  on  the  fore  slope  of  a  nearshore   fringing  reef  in  water  depths  of  5  –  17   m.    The  reef  crest  is  a  distinct  spur-­‐and-­‐ groove,  with  a  sharp  break  in  slope   leading  to  an  escarpment  that   terminates  in  a  sand/sediment  plain  at   the  reef  base.    Botany  Bay  has  been   monitored  since  2002.   Outstanding  Feature.    Botany  Bay   supports  a  diverse  and  productive  reef   that  is  one  of  the  prettiest  nearshore   reefs  in  the  Virgin  Islands  and  is   surrounded  by  one  of  the  most   aesthetically  pleasing  locales  on  St.  Thomas.   Threats.    Botany  Bay  is  threatened  by  development  of  the  previously  fully  vegetated   watershed  and  increased  land-­‐based  sources  of  pollution.    The  area  is  open  to  fishing.       Increased  residential  development  in  the  watershed  may  lead  to  increased  recreational  use   of  the  reef,  including  fishing  and   collecting.  The  area  is  also   occasionally  impacted  by  large   Atlantic  swells,  causing  breakage   of  corals.   Figure  103.    Botany  Bay.  (top)   Location.    (right)  A  representative   photo  of  the  reef.       BOTANY  BAY         176   Figure  104.    Botany  Bay  benthic  temperature  record  (11  m  depth).   Physical  Characteris.cs.    Current.    Currents  have  not  been  measured  at  directly  at  Botany   Bay.    Unidirectional  currents  do  not  tend  to  be  strong.    Wave-­‐driven  oscillatory  currents  can   impact  the  reef  crest  and  fore  reef.    The  site  is  vulnerable  to  impacts  from  large  Atlantic   swells.    Many  corals  were  broken  and  toppled  during  the  2009  March  swell  event  when   offshore  swells  reached  heights  to  4  m.    Temperature.    Botany  Bay  tends  to  have  slightly   cooler  temperatures  than  other  nearshore  sites,  likely  owing  to  its  open  position  facing  the   Atlantic.       Figure  105.    A  large  colony  of   pillar  coral  (Dendrogyra   cylindricus)  dislodge,   toppled,  and  diseased  after   the  2009  swell  event  (Botany   Bay,  June  25,  2009).       J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2006 2009 2007 2010 2008 2011 Temperature ( oC) Month SITE  SUMMARIES       177     Benthic  Community.  The  Botany  Bay  site  coral  community  is  unique  for  the  dominance  of   branching  Porites  spp.,  particularly  Porites  porites.    The  site  lost  38.9%  of  its  coral  cover  in   the  2005  bleaching  event  and  had  regained  10.6%  by  2011.    There  is  a  high  abundance  of   gorgonians  on  the  seaward  slope  exposed  to  wave  swell.    The  Botany  Bay  algal  community   is  co-­‐dominated  by  epilithic  algae  and  the  macroalga  Dictyota  spp.,  which  tend  to  negatively   covary.   Coral  Health.    Bleaching  was  extremely  severe  during  2005,  with  nearly  100%  of  corals   bleached  or  pale  over  100%  of  their  surface.    There  was  also  a  high  prevalence  of  bleaching   in  2002  at  an  unknown  extent  and  in  2010  at  a  low  extent.    Non-­‐thermal  stress  years  have   seen  variable  bleaching.    Coral  diseases  can  be  high  at  Botany  Bay,  with  a  preponderance  of   white  and  dark  spots  diseases,  and  lesions  that  are  likely  related  to  white  disease.      Old   partial  mortality  shows  a  pattern  that  is  difficult  to  explain  before  2005.    During  bleaching   and  afterwards  consistent  observers  have  done  partial  mortality  assessments  and  this  data   is  valid.    There  was  a  large  increase  in  old  partial  mortality  after  the  2005  bleaching  event,   then  some  subsidence  and  leveling  off  after  2008.    Recent  partial  mortality  was  high   through  most  years  of  monitoring,  largely  due  to  biting  by  territorial  damselfish  (Stegastes   spp.;  data  not  shown).     Figure  106.    Botany  Bay.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   BOTANY  BAY         178   Figure  107.    Botany  Bay  benthic  cover  and  coral  health  through  time  (mean  ±SE).         Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES       179     Fish  Community.  The  fish  community  at  Botany  Bay  is  typical  of  a  well  developed  nearshore   reef  around  St.  Thomas.  The  site  is  dominated  by  herbivores,  primarily  large  stoplight   parrotfish.  Large  habitat  diversity  at  the  site  supports  fish  species  richness;  and  all  trophic   groups  are  well  represented.  Botany  had  a  highly  diverse  fish  community,  similarly  to  Cane   Bay,  St.  Croix.    These  sites  may  each  be  recruitment  sinks  owing  to  their  position  on  the   northwest  sides  of  the  islands  where  eddies  tend  to  recirculate.  Red  hind,  dog  snapper  and   several  yellowtail  snapper  were  recorded  in  fish  transects  in  2012.  On  roving  dives,  spiny   lobsters  are  nearly  always  encountered.  Grunts  and  wrasses  are  especially  numerous  and   diverse  on  the  site.  Like  most  nearshore  reefs,  large  jacks  and  balistids  are  nearly  absent,   and  the  planktivore  community  is  comprised  mainly  of  blue  and  brown  chromis.         BOTANY  BAY         180     Herbivores stoplight parrotfish yellowtail damsel queen parrotfish redband parrotfish redfin parrotfish striped parrotfish threespot damsel dusky damsel blue tang Beaugregory princess parrotfish ocean surgeonfish doctorfish redlip blenny Fish Biomass 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Invertivores smallmouth grunt red hind French grunt yellowhead wrasse tomtate spotted drum striped grunt spotted goatfish dusky squirrelfish fairy basselet harlequin bass butter hamlet yellowtail hamlet clown wrasse puddingwife Spanish hogfish Fish Biomass 0 200 400 600 800 1000 1200 1400 1600 1800 2000 Planktivores brown chromis yellowtail snapper blue chromis creole wrasse bicolor damsel chalk bass Fish Biomass 0 1000 2000 3000 4000 Piscivores dog snapper great barracuda bar jack trumpetfish spotted moray glasseye snapper graysby black hamlet Fish Biomass 0 1000 2000 3000 4000 5000 SITE  SUMMARIES       181   BREWERS  BAY   Descrip(on.    Brewers  Bay  is  a  nearshore   fringing  reef  located  at  the  mouth  of   Brewers  Bay  along  the  southwest  coast   of  St.  Thomas  in  water  depths  of  7  –  17   m.  Brewers  Bay  is  a  very  well  develop   boulder  star  coral  (Orbicella  annularis)   dominated  reef.    Brewers  Bay  was   initially  monitored  in  2002/2003,  but   was  abandoned  due  to  its  proximity  to   the  Black  Point  site.    It  was  picked-­‐up   again  in  2008  due  the  excellent  coral   development  and  resistance  to   bleaching  impacts.   Outstanding  Feature.    Brewers  Bay  is   very  good  example  of  a  nearshore  boulder  star  coral  fringing  reef  and  has  fared  better  than   other  reefs  of  this  type  over  the  2005  mass  coral  bleaching  event.     Threats.    Brewers  Bay  is  subjected  to  land-­‐based  sources  of  pollution,is  located  directly   below  a  trash  dumpster  collection  area,  and  tends  to  have  turbid  water  and  overgrowth  by   heterotrophic  organisms,  such  as   sponges.    Recreational/artisanal   fishers  frequently  fish  Brewers   Bay  with  hand  line  and  spear.     The  site  has  a  great  deal  of   marine  debris,  including  boat   hulls,  rope,  and  metal  pieces.   Figure  108.    Brewers  Bay.  (top)   Location.    (right)  A  representative   photo  of  the  reef.     BREWERS  BAY       182   Physical  Characteris.cs.       Current.    Brewers  Bay  currents  have  not  been  measured  directly,  but  both  unidirectional   and  oscillatory  currents  are  usually  very  low  in  magnitude.    See  also  the  Black  Point   physical  data,  which  was  taken  within  500m  distance.   Temperature.    Brewers  Bay  temperatures  have  not  been  recorded  directly,  but  see  the   Black  Point  temperature  data.    The  site  has  restricted  flow  and  should  develop  high  warm   season  temperatures.       SITE  SUMMARIES       183     Benthic  Community.  The  Brewers  Bay  site  is  highly  dominated  by  the  boulder  coral  Orbicella   annularis  and  exhibits  the  highest  coral  cover  of  any  nearshore  site  in  the  TCRMP,  with  a   coral  cover  of  32%  in  2011.    Coral  cover  was  not  monitored  between  2003  and  2008;   however  there  was  a  28.4%  decline  in  cover  that  could  largely  be  attributed  to  the  2005   coral  bleaching  event.    The  algal  community  at  Brewers  Bay  is  dominated  by  epilithic  algae,   with  lesser  amounts  of  the  macroalga  Dictyota  spp..   Coral  Health.    Corals  at  the  Brewers  Bay  site  were  not  monitored  for  health  over  the  2005   bleaching  event.    However,  corals  exhibited  some  of  the  highest  prevalence  of  bleaching   during  the  2010  coral  bleaching  event,  albeit  at  a  low  extent.    In  other  years  bleaching   prevalence  remained  high,  with  a  low  extent.    Yellow  band  disease  outbreaks  were  severe   and  affected  the  O.  annularis  community  in  2002  and  2003.    Old  partial  mortality  is  a   prominent  and  persistent  feature  of  the  large  O.  annularis  colonies.    Recent  mortality  is  very   high  and  largely  attributable  to  the  biting  of  large  populations  of  the  territorial  three-­‐spot   damselfish  (Stegastes  planifrons;  data  not  shown).     Figure  109.    Brewers  Bay.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.         BREWERS  BAY       184       Figure  110.    Brewers  Bay  benthic  cover  and  coral  health  through  time  (mean  ±SE) Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES       185     Fish  Community.    Brewers  Bay  is  characterized  by  high  fish  abundance,  dominated  by   herbivores.    The  site  holds  large  numbers  of  parrotfish.  Numerically  the  herbivores  are   dominated  by  juveniles  that  swim  over  the  reef  in  groups  of  mixed  parrotfish  and  wrasse.     Both  yellowhead  and  bluehead  wrasse  are  prolific,  schooling  with  the  juvenile  parrotfish.     Piscivores  are  limited  in  biomass  but  are  fairly  diverse  and  generally  include  inshore   pelagics  such  as  cero  mackerel  and  bar  jacks  or  yellow  jacks.  Hamlets  (Hypoplectrus)  are   very  common  and  diverse,  represented  by  6  to  7  species  in  each  annual  survey.  The   occasional  large  snapper  (schoolmaster,  dog,  and  cubera)  are  sighted  on  the  reef  periphery   or  around  large  coral  heads.  This  nearshore  reef  is  spearfished  regularly,  so  these  species   do  not  generally  last  long.       BREWERS  BAY         186   Figure  111.    The  Brewers  Bay  fish  community  by  absolute  and  relative  biomass. Herbivores stoplight parrotfish striped parrotfish threespot damsel redband parrotfish blue tang princess parrotfish Beaugregory dusky damsel yellowtail damsel cocoa damsel orangespotted filefish ocean surgeonfish queen parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 Invertivores mutton snapper yellow goatfish bluestriped grunt French grunt sailors choice spotted drum butter hamlet yellowhead wrasse spotted goatfish slippery dick yellowtail hamlet shy hamlet clown wrasse indigo hamlet harlequin bass fairy basselet striped grunt yellowbelly hamlet Fish Biomass (g) 0 200 400 600 800 1000 1200 1400 1600 1800 Planktivores creole wrasse yellowtail snapper brown chromis blue chromis bicolor damsel tobaccofish Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 7000 Piscivores schoolmaster red lionfish graysby tiger grouper cero glasseye snapper black hamlet mahogany snapper bigeye bar jack sand diver trumpetfish Fish Biomass (g) 0 1000 2000 3000 4000 SITE  SUMMARIES       187   BUCK  ISLAND,  ST.  THOMAS   Descrip(on.    Buck  Island,  St.  Thomas  is  a   midshelf  reef  fringing  the  northwest   coast  of  an  uninhabited  offshore  island   in  water  depths  of  7  –  20  m.    The  reef   has  a  sharp  break  in  slope  leading  to  a   steep  escarpment  that  terminates  in  a   sand/sediment  plain  at  the  reef  base.     The  monitoring  site  is  located  on  that   slope.    Buck  Island,  St.  Thomas  has  been   monitored  since  2005,  with  permanent   benthic  transects  installed  in  2007.   Outstanding  Feature.    Buck  Island,  St.   Thomas  is  one  of  the  most  important   tourist  sites  in  the  Virgin  Islands,  with   frequent  visitation  by  cruise  ship  passengers  on  day  boats.   Threats.    Buck  Island,  St.  Thomas  is  very  heavily  used  as  a  recreational  dive  site  with  the   potential  for  cumulative  impacts.    The  water  surrounding  Buck  Island,  St.  Thomas  is  open  to   fishing.    Commercial  trap  fishermen  frequently  target  this  site,  and  trap  strings  have  been   laid  over  the  monitoring   transects.    Federally  protected   Nassau  Grouper  (Epinephelus   striatus)  have  been  observed   within  traps  at  the  monitoring   site.    In  addition,  derelict  traps   are  common  around  the  site.   Figure  112.    Buck  Island,  St.  Thomas.   (top)  Location.    (right)  A   representative  photo  of  the  reef.     BUCK  ISLAND       188   Figure  113.    Buck  Island,  St.  Thomas  benthic  temperature  record  (12  m  depth).     Physical  Characteris.cs.       Current.    Buck  Island,  St.  Thomas  currents  have  not  been  measured  directly.    Moderately   strong  unidirectional  currents  occasionally  influence  the  site,  however,  in  general  currents   are  very  weak.   Temperature.    Buck  Island,  St.  Thomas  may  develop  high  temperatures.    Unfortunately  the   temperature  probe  placed  during  the  2010  coral  bleaching  event  was  lost.       J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2006 2009 2007 2010 2008 2011 Temperature ( oC) Month SITE  SUMMARIES       189     Benthic  Community.  The  Buck  Island,  St.  Thomas  site  coral  community  is  dominated  by  the   boulder  star  coral  (Orbicella  spp.),  but  shows  high  and  even  representation  of  other  species.     Coral  cover  declined  by  23.4%  due  to  the  2005  coral  bleaching  event  and  the  site  had   regained  13.4%  of  this  cover  by  2011.    Among  sessile  epibenthic  animals  a  high  proportion   of  the  community  is  composed  of  sponges.    The  algal  community  is  co-­‐dominated  by   epilithic  algae  and  the  macroalgae  Dictyota  spp.  and  Lobophora  variegata.      Filamentous   cyanobacteria  were  also  abundant  in  2008.     Coral  Health.    The  Buck  Island,  St.  Thomas  site  was  severely  bleached  in  the  2005  coral   bleaching  event,  with  over  80%  of  colonies  bleached  over  100%  of  the  colony  surface.     Bleaching  was  also  high  during  the  2010  bleaching  event,  but  at  a  low  extent  on  colonies.     Low  prevalence  of  low-­‐extent  bleaching  was  common  in  other  years  of  study.    Coral   diseases  were  usually  low,  in  prevalence  with  the  striking  exception  of  2006,  when  white   diseases  and  lesions  consistent  with  recent  white  disease  reached  extremely  high   prevalence.    Old  partial  mortality  increased  rapidly  after  the  2005  bleaching  event  and  then   declined  steadily  in  following  years.     Figure  114.      Buck  Island,  St.  Thomas.  (left)  Relative  composition  of  the  sessile  epibenthic  animal   community.    (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   BUCK  ISLAND       190   Figure  115.    Buck  Island,  St.  Thomas  benthic  cover  and  coral  health  through  time  (mean  ±SE).         Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES       191   Fish  Community.    The  fish  community  at  Buck  Island,  St.  Thomas  is  diverse  and  represents   the  utilization  of  many  habitats  and  resources.  Herbivores,  especially  parrotfishes,   dominate  the  site.  However,  in  2012  the  creole  wrasse  was  the  most  prolific  fish  on  belt   transects.  Invertivores  are  also  very  diverse  and  common,  and  include  goatfishes,  several   wrasses  and  a  variety  of  grunts.  Piscivores  in  2012  were  dominated  by  schoolmaster   snapper.  No  large  grouper  or  snapper  have  been  observed  in  belt  transects  or  roving  dives.   Although  a  Territorial  Park  on  land,  the  area  is  fished  with  hook  and  line,  traps  and   speargun.  It  is  also  a  very  heavily  dove  SCUBA  and  snorkel  site.  Tourists  and  commercial   dive  operators  are  known  to  feed  fish  at  Buck  Island  and  gregarious  yellowtail  snapper  are   large  and  numerous.  Small  reef  sharks  are  also  commonly  observed.           BUCK  ISLAND       192     Herbivores stoplight parrotfish striped parrotfish redband parrotfish princess parrotfish doctorfish threespot damsel Beaugregory dusky damsel ocean surgeonfish blue tang yellowtail damsel redfin parrotfish queen parrotfish redtail parrotfish cocoa damsel greenblotch parrotfish orangespotted filefish bucktooth parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 12000 Invertivores yellowhead wrasse French grunt Spanish hogfish bluestriped grunt saucereye porgy white grunt spotted goatfish yellow goatfish blackbar soldierfish clown wrasse yellowtail hamlet harlequin bass shy hamlet puddingwife tomtate fairy basselet butter hamlet longsnout butterflyfish yellowhead jawfish spotted drum Fish Biomass (g) 0 200 400 600 800 1000 Planktivores creole wrasse blue chromis bicolor damsel yellowtail snapper black durgon brown chromis creolefish Fish Biomass (g) 0 5000 10000 15000 20000 25000 Piscivores schoolmaster bar jack graysby trumpetfish glasseye snapper black hamlet sand diver Fish Biomass (g) 0 2000 4000 6000 8000 10000 12000 SITE  SUMMARIES       193   COCULUS  ROCK   Descrip(on.    The  Coculus  Rock  site  is  a   coral  community  on  bedrock  and   pavement  in  depths  of  4  –  7  m.    The  reef   is  formed  between  emergent  rocks  and   a  sand  plain  at  7m.    Coculus  Rock  has   been  monitored  since  2001,  with  fish   community  assessment  starting  in   2009.    A  ciguatera  fish  poisoning  study   with  monthly  sampling  has  been   ongoing  since  2009.   Outstanding  Feature.    Coculus  Rock  is   located  in  the  St.  Thomas  East  End   Reserve  and  is  closed  to  taking  of  reef   fishes.    The  site  supports  a  fish   spawning  aggregation  of  redfin  parrotfish  (Sparisoma  rubripinne).  These  100+  fish  engage   in  daily  afternoon  mating  at  southeast  reef  corner.    A  ciguatera  study  with  monthly   sampling  has  been  ongoing  since  2009.   Threats.    Coculus  Rock  is  subject  to  land-­‐based  sources  of  pollution  from  the  large   Turpentine  Gut  drainage  of  the   Tutu  watershed  and  the   numerous  industrial  maritime   activities  in  Benner  Bay.     Figure  116.    Coculus  Rock.  (top)   Location.    (right)  A  representative   photo  of  the  reef  showing  the   aggregation  of  redfin  parrotfish.       BUCK  ISLAND       194   Figure  117.    Coculus  Rock  benthic  temperature  record  (7m  depth).     Physical  Characteris.cs.       Current.    Coculus  Rock  currents  have  not  been  measured  directly.    Only  weak   unidirectional  currents  have  been  experienced.    Wave-­‐driven  oscillatory  currents  can  be   intense  from  swells  coming  from  the  southeast.       Temperature.    Coculus  Rock  can  experience  very  high  temperatures  during  the  peak  warm   season.       J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2006 2009 2007 2010 2008 2011 Temperature ( oC) Month SITE  SUMMARIES       195     Benthic  Community.  The  Coculus  Rock  site  is  a  coral  community  on  bedrock  and  thin   carbonate  pavement  that  supports  a  very  diverse  coral  community  with  no  dominance  by   any  species.    The  site  lost  10.7%  of  its  coral  cover  in  the  2005  bleaching  event,  but  had   regained  76.0%  of  this  lost  cover  by  2011.    Sponges  are  a  very  prominent  component  of  the   sessile  epibenthic  animal  community.    The  algal  community  is  co-­‐dominated  by  epilithic   algae  and  the  macroalga  Dictyota  spp.,  which  tend  to  covary.   Coral  Health.    Corals  at  Coculus  Rock  were  relatively  moderately  impacted  by  the  2005  coral   bleaching  event  in  both  prevalence  and  extent  on  colonies.    This  may  be  due  to  a  coral   species  assemblage  composed  of  small  massive  species  that  tend  to  be  less  susceptible  to   bleaching  (Smith  et  al.,  unpublished  manuscript).    A  modest  prevalence  of  low  extent   bleaching  was  also  evident  in  the  2010  coral  bleaching  event.    In  years  without  high   thermal  stress  there  tends  to  be  a  relatively  high  prevalence  of  bleaching  relative  to  other   sites,  and  prior  to  2004  this  was  at  high  extent  over  colonies.    Coral  diseases,  represented   almost  exclusively  by  dark  spots  disease,  can  be  quite  high  in  some  years.    Old  partial   mortality  has  been  fairly  high  and  consistent  over  time,  with  a  slight  increase  after  the  2005   and  2010  bleaching  events.    Recent  partial  mortality  tends  to  be  quite  low  in  prevalence.       Figure  118.    Coculus  Rock.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.       BUCK  ISLAND       196     Figure  119.    Coculus  Rock  benthic  cover  and  coral  health  through  time  (mean  ±SE).       Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES       197   Fish  Community.    The  Coculus  Rock  fish  community  is  interesting  in  several  ways  and  it   represents  an  inshore  promontory  that  aggregates  redfin  parrotfish  (Sparisoma  rubripinne)   to  spawn  every  afternoon.  For  that  reason  redfin  highly  dominate  the  site  in  biomass.  The   top  of  the  reef,  emergent  at  points,  is  turbid  and  rough  with  breaking  waves,  but  large   parrotfish,  jacks,  snappers,  doctorfish  and  damselfishes  swim  in  this  area.  At  the  bottom  of   the  reef,  where  coral  and  rock  meet  the  sand,  a  small  ledge  runs  along  the  southeast  edge.   Red  hind  and  an  occasional  Nassau  grouper  have  been  observed  hiding  in  the  ledge  here.   There  are  generally  a  dozen  or  more  juvenile  lobster  using  the  ledge  as  well.  Juvenile  grunts   can  be  particularly  common  at  Coculus  Rock,  schooling  on  large  limestone  rocks  on  the   western  side  of  the  site.    Otherwise  the  fish  community  inhabiting  the  steep  walled  rock   and  algae  covered  limestone  site  is  primarily  wrasses,  small  parrotfishes  and  acanthurids.   Coculus  Rock  is  part  of  the  Territorial  East  End  Reserve  (STEER)  and  fishes  are  protected   from  all  harvest  year-­‐round.     BUCK  ISLAND       198     Herbivores redfin parrotfish stoplight parrotfish blue tang redband parrotfish ocean surgeonfish doctorfish yellowtail damsel striped parrotfish dusky damsel redtail parrotfish princess parrotfish Beaugregory threespot damsel orangespotted filefish cocoa damsel Fish Biomass (g) 0 5000 10000 15000 20000 25000 Invertivores yellowhead wrasse saucereye porgy bluestriped grunt squirrelfish French grunt puddingwife slippery dick rainbow wrasse clown wrasse harlequin bass hogfish tomtate fairy basselet Fish Biomass (g) 0 200 400 600 800 1000 1200 1400 Planktivores yellowtail snapper bicolor damsel Fish Biomass (g) 0 500 1000 1500 2000 2500 3000 Piscivores gray snapper sand diver schoolmaster graysby black hamlet trumpetfish Fish Biomass 0 200 400 600 800 1000 Fish Biomass SITE  SUMMARIES     199   COLLEGE  SHOAL   Descrip(on.    College  Shoal  is  part  of  a   mesophotic  bank  located  in  the  Red   Hind  Marine  Conservation  District  (est.   1999)  in  depths  of  28  –  33  m.    The   densely  populated  coral  reef  is   surrounded  by  continuous  reef   structure  dominated  by  boulder  star   corals  (Orbicella  annularis  spp.).    College   Shoal  has  been  monitored  since  2003,   with  permanent  benthic  transects   installed  in  2007.   Outstanding  Feature.    College  Shoal  is   notable  for  possessing  high  water   clarity,  relatively  strong  currents,  a  high  density  of  corals  (>30%  coral  cover),  and  a  great   abundance  of  fishes,  including  commercially  important  groupers  and  snappers.    College   Shoal  is  one  of  the  most  aesthetically  pleasing  reefs  for  diving  due  to  its  relatively  pristine   condition,  high  coral  abundance,  and  high  fish  abundance.   Threats.  College  Shoal  has  experienced  coral  white  diseases  at  chronically  high  levels  (>  1%   prevalence).    This  reef  also   supports  a  high  abundance  of  the   invasive  Indo-­‐Pacific  Lionfish   (Pterois  volitans).     Figure  120.    College  Shoal.  (top)   Location.    (right)  A  representative   photo  of  the  reef.     COLLEGE  SHOAL         200   Figure  121.College  Shoal  benthic  temperature  record  (29m  depth).     Physical  Characteris.cs.     Currents.    Although  not  measured  directly,  College  Shoal  has  strong  unidirectional  driven   currents  that  seem  to  be  tidally  driven  and  follow  a  pattern  of  increasing  strength  during   spring  tides.       Temperature.    Benthic  temperatures  are  ameliorated  in  the  warm  season  by  the  proximity   of  the  thermocline.    The  presence  of  the  thermocline  causes  temperatures  that  are  cool  and   diurnally  variable  from  May  to  October.    Unfortunately  the  thermistor  re-­‐initialized   improperly  in  2009  and  the  2010  coral  bleaching  event  temperatures  where  missed  at  this   site.       J F M A M J J A S O N D 24 25 26 27 28 29 30 31 32 2007 2008 2009 2010 2011 Temperature ( oC) Month SITE  SUMMARIES     201   Benthic  Community.    College  Shoal  is  among  the  TCRMP  sites  with  the  highest  coral  cover   (38.2%  in  2011)  and,  similar  to  other  bank  mesophotic  sites  south  of  the  St.  Thomas,  is   dominated  by  the  boulder  star  coral  (Orbicella  spp.).    This  site  lost  only  10.1%  of  its  coral   cover  in  the  2005  bleaching  event,  but  had  not  regained  cover  since  then  (-­‐1.3%);  however,   these  estimates  have  some  additional  error  since  transects  were  not  made  permanent  until   2007.    Sponges  and  gorgonians  are  in  very  low  relative  abundance.    The  algal  community  is   dominated  by  the  macroalga  Lobophora  variegata  and  lesser  representation  by  epilithic   algae.    There  is  also  a  relatively  high  proportion  of  crustose  coralline  algae.   Coral  Health.    College  Shoal  bleached  at  a  relatively  low  prevalence  during  the  2005  mass   coral  bleaching  event,  although  corals  that  were  bleached  tended  to  lose  color  over  their   entire  surface.    The  2010  coral  bleaching  event  had  no  apparent  effect  above  background   bleaching  levels.    Bleaching  in  years  without  thermal  stress  tends  to  be  moderate.    Diseases   were  dominated  by  white  disease,  which  reached  very  high  prevalence  after  the  2005   bleaching  event,  with  an  outbreak  that  lasted  for  two  years  in  2006  and  2007.    This  disease   was  again  very  prevalent  in  2011  after  the2010  bleaching  event,  even  without  apparent   thermal  bleaching.    Old  partial  mortality  was  elevated  on  corals  after  the  mortality  from  the   2005  bleaching  event,  and  this  level  has  remained  stable  through  2011.    Recent  partial   mortality  is  always  relatively  high,  much  of  it  attributable  to  fish  bites.   Figure  122.    College  Shoal  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.     COLLEGE  SHOAL         202   Figure  123.    College  Shoal  benthic  cover  and  coral  health  through  time  (mean  ±SE).       Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES     203   Fish  Community.    College  Shoal  is  characterized  by  a  high  fish  biomass  and  high  species   diversity.    Large  planktivores  are  also  characteristic  of  College  Shoal,  including  ocean   triggerfish,  Atlantic  spadefish,  black  jacks  and  yellowtail  snapper.    Numerically,  the  site  is   dominated  by  creole  wrasse;  however  large  jacks,  snappers,  ocean  triggerfish  and  black   durgeon  are  common.    College  Shoal  lies  within  the  Marine  Conservation  District  (MCD)   and  is  protected  year  round  from  all  fishing.  Nassau,  yellowfin,  yellowmouth  and  tiger   grouper  are  occasionally  observed  on  the  site.    The  mesophotic,  high  coral  cover  reef   supports  less  herbivores  than  the  more  shallow  nearshore  and  offshore  sites;  however,   more  herbivores  (ocean  surgeonfish)  are  present  than  on  the  significantly  deeper  Hind   Bank  and  Grammanik  Bank.    Diversity  is  high  in  all  trophic  guilds  indicating  a  high  variety   of  micro-­‐niches  available  for  fishes.         COLLEGE  SHOAL         204   Figure  124.    The  College  Shoal  fish  community  by  absolute  and  relative  biomass. Herbivores princess parrotfish stoplight parrotfish ocean surgeonfish queen parrotfish redband parrotfish blue tang doctorfish Beaugregory threespot damsel greenblotch parrotfish striped parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 Invertivores saucereye porgy yellow goatfish red hind queen trigger permit white grunt spotted goatfish blackbar soldierfish yellowhead wrasse porkfish French grunt bluestriped grunt dusky squirrelfish Spanish hogfish slippery dick longsnout butterflyfish fairy basselet harlequin bass yellowtail hamlet Fish Biomass (g) 0 5000 10000 15000 20000 25000 Planktivores ocean trigger yellowtail snapper black durgon creole wrasse black jack blue chromis bicolor damsel creolefish boga brown chromis Fish Biomass (g) 0 5e+4 1e+5 2e+5 2e+5 3e+5 3e+5 Piscivores cubera snapper bar jack horse-eye jack schoolmaster great barracuda dog snapper yellowfin grouper cero red lionfish graysby Fish Biomass (g) 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 SITE  SUMMARIES     205   FLAT  CAY   Descrip(on.    This  monitoring  site  wraps   around  the  northwest  corner  depths  of   Flat  Cay  in  depths  of  10  –  17  m.    Black   Point  has  been  monitored  since  2003,   with  permanent  benthic  transects   installed  in  2007.    A  ciguatera  fish   poisoning  study  with  monthly  sampling   has  been  ongoing  since  2009.   Outstanding  Feature.    Flat  Cay  supports   a  lush  coral  community,  including  dense   populations  of  the  endangered  elkhorn   and  staghorn  corals  (Acropora  spp.)   outside  the  TCRMP  monitoring  site.    The   site  is  a  popular  tourist  dive  site  and  is   an  important  site  for  research  by  local  and   international  investigators.   Threats.    Flat  Cay  is  down  current  of  industrial   port  activities  and  a  major  sewage  outfall.     Mollusks,  including  the  commercially   important  queen  conch  (Strombus  gigas)  show   sterility  (imposex)  as  a  likely  result  of  exposure   to  hormone  mimics  released  from  boat  hulls   coated  with  marine  antifouling  paint   containing  Tributyltin  (Strand  et  al.  2009).  The   area  experiences  heavy  fishing  and  damage   from  anchoring  within  the  reef.   Figure  125.    Flat  Cay.  (top)  Location.    (right)  A   representative  photo  of  the  reef.     FLAT  CAY       206   Figure  126.    Flat  Cay  benthic  current  speed  (left)  and  temperature  record  (right)  (14m  depth).     Physical  Characteris.cs.       Current.    The  benthic  current  at  the  Flat  Cay  site  is  weak  and  dominated  by  a  south-­‐ southwesterly  flow.    This  may  be  an  effect  of  the  wrapping  of  the  generally  westward  and   occasionally  strong  surface  current.    Currents  were  measured  with  an  Aandaraa  2-­‐D   current  meter  measuring  1m  above  the  seafloor.   Temperature.    Flat  Cay  experiences  moderate  warming  for  a  shallow  water  site  and  rapid   cooling  with  the  passage  of  tropical  storms.       J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2003 2004 2005 2006 2009 2007 2010 2008 2011 Temperature ( oC) Month N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW Current velocity (m s -1) 0.2 - 0.3 0.1 - 0.2 0.0 - 0.1 SITE  SUMMARIES     207     Benthic  Community.  Flat  Cay  supports  a  diverse  coral  community  with  dominance  of   boulder  star  corals  (Orbicella  spp.).    The  sessile  epibenthic  animal  community  also  shows  a   high  abundance  of  sponges.    The  site  lost  a  moderate  21.9%  of  cover  in  the  2005  bleaching   event  and  had  regained  159.3%  of  this  cover  by  2011.    A  caveat  is  that  transects  were  not   made  permanent  until  2007.    Epilithic  algae  and  the  macroalga  Dictyota  spp.,  with  lesser   amounts  of  Lobophora  variegata,  dominate  the  algal  community.    Sand  in  pockets  between   coral  also  makes  up  a  fair  amount  of  the  non-­‐living  substrate.   Coral  Health.    Corals  were  severely  affected  during  the  2005  coral  bleaching  event,  with   over  90%  of  corals  bleached  at  100%  extent  of  the  colony  surface.    Bleaching  was  also   moderately  prevalent  in  the  2010  bleaching  event,  but  at  low  extent.    Coral  diseases,   particularly  dark  spots  disease  can  be  very  prevalent  at  Flat  Cay.    There  was  an  unusual   outbreak  of  black  band  disease  in  2004.    This  disease  is  rare  at  the  depths  of  Flat  Cay.     White  disease  was  somewhat  prevalent  after  the  2005  bleaching.    Old  partial  mortality   increased  rapidly  after  the  2005  bleaching  event  and  has  not  decreased  in  the  intervening   years.    Recent  mortality  can  be  moderate  and  is  due  to  a  variety  of  causes.     Figure  127.    Flat  Cay  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.    (right)   Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   FLAT  CAY       208     Figure  128.    Flat  Cay  benthic  cover  and  coral  health  through  time  (mean  ±SE).       Benthic Community Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae Bleaching Prevalence/Extent 0% 20% 40% 60% 80% 100% Prevalence Extent Disease Prevalence 0% 5% 10% 15% 20% 25% 30% All disease Black Band Lesion Dark Spots Intercostal White Disease Yellow Band Unknown Partial Mortality 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Prevalence 0% 20% 40% 60% 80% 100% Old Recent SITE  SUMMARIES     209     Fish  Community.    Flat  Cay  is  characterized  by  a  large  diversity  of  fish  evenly  distributed   across  tropic  guilds.    There  is  a  higher  biomass  of  invertivores  than  other  groups  due  to  the   regular  occurrence  of  large  schools  of  creole  wrasse.    Herbivores  are  dominated  by  redband   and  striped  parrotfish;  however,  there  is  a  diversity  of  parrotfish  species.    Juvenile   parrotfish  are  prevalent.    Carangids  frequent  the  reef  and  dominate  the  piscivore  trophic   group.    Occasional  large  groupers  (Nassau,  yellowfin,  black)  have  been  observed  on  Flat  Cay   over  the  past  eight  years.    The  occasional  occurrence  of  black  grouper  is  notable,  since  this   species  is  absent  throughout  the  majority  of  monitoring  sites.    The  reef  is  highly  used  as  a   recreational  dive  site  and  spearfishing  occurs  regularly.    Where  the  reef  meets  the  sand   offshore,  schools  of  grunts,  gray  snapper,  and  goatfish  occur.    Small  reef  sharks  are  seen  out   over  the  sand  regularly.           FLAT  CAY       210   Figure  129.    The  Flat  Cay  fish  community  by  absolute  and  relative  biomass. Herbivores stoplight parrotfish redband parrotfish striped parrotfish queen parrotfish threespot damsel doctorfish princess parrotfish blue tang Beaugregory dusky damsel greenblotch parrotfish ocean surgeonfish cocoa damsel orangespotted filefish Fish Biomass 0 2000 4000 6000 8000 10000 Invertivores French grunt yellow goatfish squirrelfish bluestriped grunt spotted goatfish tomtate saucereye porgy yellowhead wrasse white grunt Spanish hogfish porcupine indigo hamlet yellowtail hamlet butter hamlet shy hamlet bandtail puffer blackear wrasse harlequin bass striped grunt fairy basselet Fish Biomass 0 1000 2000 3000 4000 Planktivores brown chromis yellowtail snapper creole wrasse bicolor damsel blue chromis black durgon chalk bass tobaccofish Fish Biomass 0 1000 2000 3000 4000 5000 Piscivores bar jack graysby great barracuda schoolmaster trumpetfish dog snapper black hamlet redspotted hawkfish Fish Biomass 0 1000 2000 3000 4000 SITE  SUMMARIES     211   GINSBURGS  FRINGE   Descrip(on.    Ginsburgs  Fringe  is  a   mesophotic  lettuce  coral  (Agaricia  spp.)   reef  at  depths  of  60-­‐75m.    The  reef  is  on  a   steep  escarpment  dropping  into  the   abyssal  Virgin  Islands  trough.    Ginsburgs   Fringe  has  been  monitored  since  2011  and   permanent  transects  have  been  installed.   Outstanding  Feature.    Ginsburgs  Fringe  had   the  highest  2011  coral  cover  among  all   TCRMP  monitoring  sites  (44%),  with   living  colonies  of  lettuce  corals  over  6m   (20’)  wide.    This  site  is  the  epicenter  of  a   multispecies  fish  spawning  aggregation,   including  the  threatened  Nassau  grouper  (Epinephelus  striatus).    The  site  name  honors  the   father  of  comparative  sedimentology  and  mesophotic  coral  studies,  Dr.  Robert  N.  Ginsburg.   Threats.  Although  little  is  known  about  conditions  in  deep  mesophotic  lettuce  coral  reefs,   Ginsburgs  Fringe  appears  to  be  almost  unscathed  by  recent  mass  coral  bleaching  events.     Lettuce  corals  at  these  depths  are  potato  chip  thin  and  fragile,  making  them  vulnerable  to   damage,  such  as  the  laying  of   benthic  cables.    The  site  is  being   heavily  invaded  by  the  Indo-­‐ Pacific  lionfish  (Pterois  volitans).     Figure  130.    Ginsburgs  Fringe.  (top)   Location.    (right)  A  representative   photo  of  the  reef  showing  whorled   lettuce  coral  colonies  up  to  7m  in   width.     GINSBURGS  FRINGE       212     Figure  131.    Ginsburgs  Fringe  current  speed  (50m  depth).     Physical  Characteris.cs.       Current.    Currents  have  been  measured  above  the  site  in  50  m  depth.There  is  a  strong   offshelfdownwelling  (southward)  that  occurs  just  above  the  site,  potentially  carrying  larvae   and  heterotrophic  food  supplies  to  the  site.       Temperature.    Temperature  loggers  have  not  yet  been  retrieved  from  the  site,  but  a   thermistor  string  is  in  place  at  and  above  the  site,  with  loggers  at  30,  40,  50,  and  63  m   depth.       N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW Current Speed (m s -1) 0.4 - 0.5 0.3 - 0.4 0.2 - 0.3 0.1 - 0.2 0.0 - 0.1 SITE  SUMMARIES     213     Benthic  Community.  The  coral  community  at  Ginsburgs  Fringe  is  almost  exclusively  lettuce   corals  of  the  genus  Agaricia.    Among  the  agariciid  genus,  the  rank  abundance  of  species  is  A.   undata  (30.8%  absolute  cover),  A.  grahamae  (8.2%),  and  A.  lamarcki  (2.3%),  with  no   colonies  of  A.  agaricites  and  A.  fragilis  occurring  in  transects.    Although  not  well   represented  in  cover,  individual  colonies  of  Montastraea  cavernosa  and  Siderastrea  siderea   also  occur  at  the  site.    The  algal  community  is  dominated  by  the  macroalga  Lobophora   variegata,  which  is  surprising  for  these  depths,  and  epilithic  algae.    Crustose  coralline  algae   are  also  in  high  abundance,  as  well  as  a  variety  of  unidentified  algal  species.       Coral  Health.    Coral  health  is  not  directly  monitored  at  Ginsburgs  Fringe  due  to  the  depth   and  difficulties  assessing  colonies  greater  than  3m  width.    However,  some  observations   have  been  made.    What  appears  to  be  warm  season  bleaching  appears  to  occur.    Colonies   have  a  fair  degree  of  partial  mortality  and  recent  mortality  is  very  common.    In  some  cases   it  appears  that  shaded  colony  portions  die  back  due  to  lack  of  light.    The  corallivorous  snail,   Coralliophila  abbreviata,  has  been  observed  feeding  on  lettuce  corals.     Figure  132.    Ginsburgs  Fringe.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.     GINSBURGS  FRINGE       214     Figure  133.    Ginsburgs  Fringe  benthic  cover  through  time  (mean  ±SE).         Benthic Community 2001 2002 2003 2004 2005 2005 BL 2006 2007 2008 2009 2010 2011 2012 Cover 0% 20% 40% 60% 80% 100% Coral Cyanobacteria Epilithic Algae Macroalgae