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SITE  SUMMARIES     215   GRAMMANIK  TIGER   Descrip(on.    The  Grammanik  Tiger   monitoring  site  is  a  primary  bank   mesophotic  reef  in  depths  of  37  –   41m.Boulder  star  corals  (Orbicella   annularis  spp.)  dominate  the  reef   structure.    Grammanik  Tiger  has  been   monitored  since  2003,  with  permanent   transects  installed  in  2007.   Outstanding  Feature.    The  Grammanik   Tiger  monitoring  site  supports  a  dense   coral  community  that  is  a  staging  area   for  annual  multi-­‐species  fish  spawning   events,  including  the  threatened  Nassau   grouper  (Epinephelus  striatus).   Threats.    Although  the  Grammanik  Tiger  site  and  surrounding  dense  reefs  are  somewhat   buffered  from  high  thermal  stress,  but  they  are  susceptible  to  chronic  coral  white  diseases.     Periodic  disease   outbreaks  follow  coral   bleaching  events.  The   Indo-­‐Pacific  lionfish   (Pterois  volitans)  has   formed  dense  populations   within  the  study  area  and   may  be  affecting  native   fish  populations.   Figure  134.    Grammanik   Tiger  (top)  Location.    (right)     A  representative  photo  of  the   reef.     GRAMMANIK  TIGER       216       Figure  135.    Grammanik  Tiger  benthic  currents  speed  and  temperature  record  (38  m  depth).     Physical  Characteris*cs.       Current.    Unidirectional  benthic  currents  at  the  Grammanik  Tiger  site  are  generally  north-­‐ south,  with  the  strongest  current  from  the  north-­‐northeast  to  the  northwest.    Currents  are   typically  weak  to  moderate,  but  occasionally  reach  strengths  greater  than  30cm  s-­‐1.    Current   speeds  are  based  on  near-­‐continuous  ADCP  deployments  from  February  2005  to  April   2009,  with  measurements  at  30  or  60  minute  intervals.    Oscillatory  currents  are  nil  at  this   depth,  with  the  possible  exception  of  long  period  swells  generated  by  tropical  storms,   although  this  has  not  been  measured.   Temperature.    Benthic  temperatures  at  Grammanik  Tiger  are  ameliorated  by  the  passage   of  tidally  driven  internal  tides  in  the  warm  season  (May-­‐November).    Even  in  2005  and   2010  when  shallow  waters  were  there  warmest  during  monitoring,  temperatures  at  this   site  were  less  than  the  shallow  water  bleaching  threshold.    However,  the  monthly  maximum   mean  of  surface  waters  established  for  the  region  is  routinely  surpassed.    Inter-­‐annual   variability  creates  temperatures  that  can  be  up  to  2°C  different  for  the  same  Julian  Day.       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 N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW Current Speed (m s -1) 0.6 - 0.7 0.5 - 0.6 0.4 - 0.5 0.3 - 0.4 0.2 - 0.3 0.1 - 0.2 0.0 - 0.1 SITE  SUMMARIES     217   Benthic  Community.  Boulder  star  corals  (Orbicella  spp.)  dominated  the  coral  community  of   the  Grammanik  Tiger  site;  however,  there  is  representation  by  a  high  number  of  other   species  that  are  also  present  in  shallow  water  reefs.    Grammanik  Tiger  lost  only  5.4%  of  its   coral  cover  in  the  2005  bleaching  event,  but  had  not  regained  any  cover  (-­‐129.6%)  by  2011.     A  caveat  is  that  transects  were  not  made  permanent  until  2007.    Other  prominent  members   of  the  sessile  epibenthic  animal  community  are  sponges.        The  macroalga  Lobophora   variegata  and  epilithic  algae  dominate  the  algal  community.    There  are  also  a  relatively  high   proportion  of  crustose  coralline  algae  and  various  other  macroalgae  species.   Coral  Health.    Corals  at  Grammanik  Tiger  were  very  weakly  affected  by  bleaching  in  2005,   with  only  about  10%  of  corals  exhibiting  bleaching;  however,  those  that  bleached  had   nearly  70%  of  the  colony  surface  affected.    The  2010  bleaching  event  was  not  detectible   above  background  bleaching  levels.    The  prevalence  of  belaching  in  normal  years  is  quite   high,  but  at  low  extent.    This  and  other  mesophotic  reefs  dominated  by  Orbicella  spp.   exhibit  a  type  of  granular  bleaching,  whereby  pigmented  spots  are  surrounded  by  bleached   areas.    Coral  diseases  are  very  prevalent  with  high  representation  of  white  disease.    Yellow   band  disease  was  reported  at  high  prevalence  in  the  first  years  of  monitoring.    Old  partial   mortality  was  low,  but  increased  rapidly  after  the  2005  coral  bleaching  event.    Recent   partial  mortality  is  typically  very  high  and  is  caused  by  disease  lesions,  predations,  and  fish   bites.   Figure  136.    Grammanik  Tiger  FSA.    (left)  Relative  composition  of  the  sessile  epibenthic  animal   community.    (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   GRAMMANIK  TIGER       218     Figure  137.    Grammanik  Tiger  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     219   Fish  Community.    The  Grammanik  Tiger  site  supports  less  herbivores  and  a  greater  number   of  piscivores  than  the  more  shallow  sites  in  the  TCRMP.    It  is  within  the  staging  area  and   near  the  spawning  site  of  an  aggregation  of  several  species  of  grouper  and  snapper.    Given   the  range  of  spawning  species  encountered,  surveys  often  coincide  with  the  occurrence  of   aggregations,  particularly  in  those  species  with  protracted  spawning  seasons  (e.g.,  cubera   and  schoolmaster  snapper).    This  drives  up  the  relative  piscivore  biomass;  however,  on  the   Grammanik  Bank  there  also  commonly  occur  members  of  the  pelagic  jack  family   (Carangidae)  as  well  as  occasional  other  large  non-­‐spawning  grouper  and  snapper  that  are   rarely  or  never  found  on  the  near  and  offshore  reefs.    Nassau,  yellowfin,  yellowmouth  and   tiger  grouper  are  present  during  non-­‐spawning  periods.    This  reef  is  protected  from  traps   year  round,  and  from  all  fishing  gear  from  March  through  May.    Creole  wrasse  dominate  the   invertivores  and  adult  stoplight  parrotfish  dominates  herbivores.    Juvenile  parrotfish  and   doctorfish  are  relatively  uncommon  on  this  and  all  mesophotic  sites.    Yellowhead  and   bluehead  wrasse  are  also  notably  much  less  common  on  the  Grammanik  Bank  than  other   sites.    In  recent  years  the  invasive  Indo-­‐Pacific  lionfish  (Pterois  volitans)  has  become  very   common,  with  tens  of  individual  commonly  observed  on  any  given  dive.       GRAMMANIK  TIGER       220   Figure  138.    The  Grammanik  Tiger  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     221   HIND  BANK   Descrip(on.    The  Hind  Bank  is  a   mesophotic  tertiary  bank  in  depths  of   38  –  42  m.    The  reef  is  part  of  a  patchy   complex  of  boulder  star  coral  (Orbicella   annularis  spp.)  dominated  reefs  that   stretch  across  the  eastern  Red  Hind   Marine  Conservation  District.  The  Hind   Bank  has  been  monitored  since  2003,   with  permanent  benthic  transects   installed  in  2007.   Outstanding  Feature.    The  Hind  Bank  is   within  a  no-­‐take  marine  reserve  and  fish   populations  are  recovering  and  robust.     The  Hind  Bank  monitoring  site  hosts  a   multispecies  spawning  aggregation,  including  a  recovering  mating  population  of  the   commercially  important  red  hind  grouper  (Epinephelus  guttatus).   Threats.  The  Hind  Bank  and  surrounding  dense  reefs  are  somewhat  buffered  from  high   thermal  stress,  but  they  are  susceptible  to  chronic  coral  white  diseases.    Periodic  disease   outbreaks  follow  high  thermal   stress.    The  Indo-­‐Pacific  lionfish   (Pterois  volitans)  has  formed   dense  populations  within  the   study  area  and  may  be  affecting   native  fish  populations.   Figure  139.      Hind  Bank  (top)   Location.    (right)    A  representative   photo  of  the  reef.     HIND  BANK       222   Figure  140.    Hind  Bank  benthic  current  speed  (40m   depth).    Benthic  temperature  record  at  20,  30,  and  40   m  depth.   Physical  Characteris.cs.       Current.    Hind  Bank  has  moderately  strong   unidirectional  near-­‐benthic  currents  that  are   dominated  by  a  north  to  south  components.     Currents  can  be  moderate  to  strong  (>20cm  s-­‐1).     Current  speeds  are  based  on  near-­‐continuous   ADCP  deployments  from  February  2005  to  May   2012,  with  measurements  at  30  or  60  min.   intervals.    Oscillatory  currents  are  not  known   from  the  Hind  Bank.       Temperature.    Benthic  temperatures  at  the  Hind   Bank  were  augmented  with  a  subsurface  buoyed   thermistor  string  carrying  thermistors  at  20  and  30m  depth.    Benthic  temperatures  show   strong  inter-­‐annual  variability,  but  were  much  cooler  than  temperatures  in  the  mixed  layer   at  20m  depth.    This  was  particularly  evident  in  2010,  when  temperatures  were  warmest  at   20m  in  late  August  during  coral  bleaching,  temperatures  were  unseasonably  cool  on  the   bottom.    The  30m  thermistor  was  intermediate,  with  warming  to  near  the  bleaching   threshold  in  2010,  but  not  surpassing  the  threshold  like  the  20m  depth.    One  caveat  for  the   accuracy  of  the  20  and  30m  thermistors  is  that  they  can  change  depth  to  some  degree  by   bowing  of  the  buoy  line  by  currents.       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 J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2008 2010 2009 2011 Temperature ( oC) Month J F M A M J J A S O N D 24 25 26 27 28 29 30 31 2008 2010 2009 2011 Temperature ( oC) Month 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     223   Benthic  Community.  The  Hind  Bank  site  is  dominated  by  boulder  star  corals  (Orbicella  spp.),   but  also  has  a  high  abundance  of  lettuce  corals  (Agaricia  spp.).    The  Hind  Bank  site  lost   21.8%  of  its  coral  cover  in  the  2005  bleaching  event,  but  had  regained  71.4%  of  this  cover   by  2011.    The  algal  community  is  co-­‐dominated  by  epilithic  algae  and  the  macroalga   Lobophora  variegata.    There  is  also  high  representation  of  crustose  coralline  algae  and   other  unidentified  macroalgal  species.   Coral  Health.    Bleaching  during  the  2005  event  was  nearly  indistinguishable  from   background  levels  of  bleaching  in  both  prevalence  and  extent.    The  prevalence  of  bleaching   was  actually  higher  during  the  2010  coral  bleaching  event.    In  later  years  the  high   prevalence  of  moderate  prevalence,  low  colony  extent  bleaching  was  often  associated  with   granular  bleaching.    This  bleaching  pattern  shows  pigmented  spots  surrounded  by   bleached  tissue.    Coral  diseases  are  common  at  the  Hind  Bank  and  may  be  increasing.     White  disease  was  the  dominant  disease,  and  2011  showed  a  peak  of  disease  signs.    In  2009   there  was  a  high  prevalence  of  intercostal  mortality  syndrome,  which  is  only  known  from   mesophotic  coral  reefs  (Smith  et  al.  2010a).    Old  partial  mortality  increased  after  the  2005   bleaching  event  and  the  high  prevalence  was  not  reduced  until  2011.    Recent  partial   mortality  prevalence  is  often  high  and  reflects  the  impacts  of  disease  and  predation.     Figure  141.    Hind  Bank.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   HIND  BANK       224     Figure  142.    Hind  Bank  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     225     Fish  Community.    The  Hind  Bank  is  characterized  by  a  high  number  of  piscivorous  fish.    The   site  is  within  the  Marine  Conservation  District  (MCD)  and  is  protected  year  round  from  all   fishing.    It  is  the  spawning  site  for  several  species  including  red  hind,  mutton  snapper,  tiger   grouper  and  schoolmaster  snapper.    Surveys  often  coincide  with  the  occurrence  of   schoolmaster  snapper.  This  drives  up  the  relative  piscivore  biomass;  however,  there  also   commonly  occurs  members  of  the  pelagic  jack  family  (Carangidae)  and  large  barracuda.     Invertivores  are  dominated  by  goatfish,  likely  a  result  of  the  proximity  of  sand  areas  around   the  reef.  Creole  wrasse  are  not  nearly  as  dominant  as  on  other  mesophotic  sites.     Herbivores  are  less  common  than  on  nearshore  sites  and  are  dominated  by  adult  or  semi-­‐ adult  princess  parrotfish.    Juvenile  parrotfish  and  surgeonfish  are  uncommon,  as  on  all   mesophotic  sites.    Yellowhead  wrasse  are  fairly  common  on  the  Hind  Bank,  however   bluehead  wrasse  are  not.           HIND  BANK       226   Figure  143.    The  Hind  Bank  East  fish  community  by  absolute  and  relative  biomass. Herbivores stoplight parrotfish queen parrotfish ocean surgeonfish redband parrotfish princess parrotfish blue tang striped parrotfish doctorfish Fish Biomass (g) 0 500 1000 1500 2000 2500 3000 Invertivores queen trigger mutton snapper Nassau grouper porkfish blackbar soldierfish permit red hind hogfish clown wrasse French grunt bluestriped grunt white grunt cottonwick squirrelfish Spanish hogfish longsnout butterflyfish yellowhead wrasse yellowtail hamlet dusky squirrelfish spotted goatfish Caesar grunt shy hamlet fairy basselet bandtail puffer Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 Planktivores yellowtail snapper creole wrasse blue chromis black jack creolefish bicolor damsel sunshinefish Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 7000 Piscivores horse-eye jack schoolmaster yellowjack bar jack dog snapper red lionfish cero mahogany snapper graysby gray snapper king mackeral black hamlet trumpetfish Fish Biomass (g) 0 2e+4 4e+4 6e+4 8e+4 1e+5 SITE  SUMMARIES     227   LITTLE  SAINT  JAMES   Descrip(on.    The  Little  St.  James  site  is  a   midshelf  hardbottom  reef  in  depths  of   16-­‐22m.    The  reef  is  a  patch  reef   surrounded  by  sand/rhodolith  plain.       Little  St.  James  has  been  monitored   since  2005,  with  permanent  benthic   transects  installed  in  2007.   Outstanding  Feature.    The  Little  St.   James  site  is  just  outside  the  St.  Thomas   East  End  Reserve  and  supports   occasionally  high  densities  of  snappers,   grunts,  and  queen  trigger.   Threats.    Commercial  fisherman  target   the  Little  St.  James  site  and  active  and  derelict  fish  traps  are  in  high  abundance.    The  site  is   down-­‐current  of  development  on  Little  St.  James  Island  and  is  potentially  threatened  by   land-­‐based  source  of  pollution.           Figure  144.    Little  St.  James.   (top)  Location.    (right)    A   representative  photo  of  the   reef.       LITTLE  SAINT  JAMES         228   Figure  145.    Little  St.  James  benthic  temperature  record  (19m  depth).     Physical  Characteris.cs.       Current.    Currents  have  not  been  directly  measured  at  St.  James.    Unidirectional  benthic   currents  have  only  been  weak  during  monitoring.    Strong  wave-­‐driven  oscillatory  currents   may  take  place,  as  evidenced  by  the  high  proportion  of  gorgonians  and  Sargassum  spp.  at   the  site.   Temperature.    Benthic  temperatures  at  St.  James  can  be  high  during  warm  years,  such  as   2010.       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     229     Benthic  Community.    The  sparse  coral  community  of  the  Little  St.  James  site  is  diverse.     There  is  a  high  proportion  of  rare  species,  such  as  Eusmilia  fastigiatum,  Madracis  spp.,  and   Mycetophyllia  spp..    The  site  lost  16.5%  of  coral  cover  in  the  2005  bleaching  event  but  had   apparently  regained  376.2%  of  this  loss  by  2011.    This  large  increase  above  bleaching   losses  may  be  explained  by  the  fact  that  transects  were  not  made  permanent  until  2007  and   were  then  sited  in  areas  with  the  densest  coral.    The  sessile  epibenthic  community  overall  is   largely  composed  of  sponges  and  gorgonians.    The  algal  community  is  dominated  by  the   macroalgae  Dictyota  spp.  and  the  Sargassum  spp.    Lobophora  variegata  and  epilithic  algae   are  also  in  high  proportional  abundance.   Coral  Health.    The  coral  community  at  Little  St.  James  was  highly  affected  by  the  2005  coral   bleaching  event,  with  all  corals  assessed  completely  bleached.    Half  the  corals  were  affected   by  low  extent  bleaching  in  2010.    Low-­‐level  bleaching  is  a  common  feature  of  the  site.     Diseases  are  less  common,  with  the  exception  of  a  white  disease  outbreak  that  preceded  the   coral  bleaching  event  in  June  2005.    Dark  spots  disease  can  also  be  common.    Old  partial   mortality  increased  rapidly  after  the  2005  bleaching  event.    Recent  partial  mortality  is  not   very  prominent.     Figure  146.    Little  St.  James.    (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   LITTLE  SAINT  JAMES         230     Figure  147.    Little  St.  James  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     231     Fish  Community.  The  fish  community  of  Little  St.  James  differs  slightly  from  those  of  the   more  developed  reef  habitats,  and  better  represents  a  hard  bottom  fish  community.    Queen   triggerfish  and  mutton  snapper  are  far  more  common  on  Little  St.  James  than  on  other   TCRMP  sites.  Red  hind  are  also  very  common,  especially  for  a  nearshore  site.  The  reef  is   outside  of  the  boundaries  of  the  St.  Thomas  East  End  Reserves,  and  fish  traps  are  observed   regularly  on  the  site.  During  parts  of  the  year,  grunts  (French,  and  white)  have  been   observed  in  huge  numbers,  and  may  use  the  site  for  spawning.  Bar  and  yellow  jacks  are   very  common  swimming  in  the  water  column  above  the  Little  St.  James  site,  and  the   schoolmaster,  gray,  and  mahogany  snapper  are  the  major  benthic  piscivores.  All  three  of   these  species  are  considered  ciguatoxic  in  this  area  and  so  are  not  targeted  by  hook  and  line   or  spear  fishermen.         LITTLE  SAINT  JAMES         232     Herbivores doctorfish stoplight parrotfish striped parrotfish blue tang redband parrotfish ocean surgeonfish princess parrotfish Beaugregory queen parrotfish yellowtail damsel threespot damsel greenblotch parrotfish dusky damsel Fish Biomass (g) 0 2000 4000 6000 8000 10000 Invertivores queen trigger bluestriped grunt mutton snapper red hind French grunt yellowhead wrasse squirrelfish spotted goatfish harlequin bass saucereye porgy white grunt Spanish hogfish clown wrasse shy hamlet Fish Biomass (g) 0 5000 10000 15000 20000 25000 Planktivores tobaccofish bicolor damsel yellowtail snapper blue chromis creole wrasse ocean trigger brown chromis Fish Biomass (g) 0 1000 2000 3000 4000 5000 Piscivores bar jack schoolmaster gray snapper graysby horse-eye jack red lionfish mahogany snapper trumpetfish sand diver redspotted hawkfish black hamlet Fish Biomass (g) 0 5000 10000 15000 20000 25000 30000 35000 SITE  SUMMARIES     233   MAGENS  BAY   Descrip(on.    The  Magens  Bay  site  is  a   nearshore  fringing  reef  located  along   Peterborg  Point  in  depths  of  4  –  14  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.    Magens  Bay  has  been   monitored  since  2001.   Outstanding  Feature.    The  Magens  Bay   site  is  well  protected  northside  reef  near   one  of  the  most  popular  tourist  beaches   in  the  Caribbean.   Threats.    Magens  Bay  is  in  a  highly   enclosed  embayment  receiving  a  very  large  and  developed  watershed.    Sediment  run-­‐off  is   high  and  deposition  on  reefs  is  favored  by  slow  current  speeds.    In  addition,  leaky  septic   systems  may  impair  bay  waters.    Recreational/artisanal  fishers  frequently  fish  this  site  with   hand  line  and  spear.             Figure  148.    Magens  Bay.   (top)  Location.    (right)    A   representative  photo  of  the   reef.       MAGENS  BAY       234   Figure  149.    Magens  Bay  current  speed  and  benthic  temperature  record  (9  m  depth).   Physical  Characteris.cs.    Current.    Magens  Bay  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.    Current  data  are  based  on  average  data   from  Dec.  2006-­‐Oct.  2007  7.5  m  above  the  sensor  head.    Temperature.    Black  Point  has  low   circulation,  but  temperatures  are  kept  cooler  by  exposure  to  the  Atlantic.    Chlorophyll  &   Turbidity.    Magens  Bay  is  susceptible  to  very  high  chlorophyll  and  turbidity  values   indicating  very  high  productivity  that  is  likely  fueled  by  terrestrial  run-­‐off.    By  blocking  light   this  shallows  the  depth  limits  for  coral  growth  and  water  column  productivity  favors   heterotrophic  organisms,  such  as  sponges  and  gorgonians.     Figure  150.    Magens  Bay  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) 0.4 - 0.5 0.3 - 0.4 0.2 - 0.3 0.1 - 0.2 0.0 - 0.1 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     235     Benthic  Community.  The  sparse  coral  community  at  Magens  Bay  is  very  diverse,  with  no  real   dominance  by  any  one  species.    The  site  lost  12.4%  of  its  coral  cover  in  the  2005  bleaching   and  has  continued  to  lose  coral,  with  a  cover  loss  of  33.1%  from  2005  pre-­‐bleaching  to   2011.    Gorgonians  and  then  sponges  dominate  the  sessile  epibenthic  community.    Epilithic   algae  and  the  macroalga  Dictyota  spp.  dominate  the  algal  community.    Filamentous   cyanobacteria  are  also  common.    There  is  a  high  proportion  of  sand/sediment  around   corals  at  the  Magens  Bay  site.   Coral  Health.    Corals  were  highly  affected  by  the  2005  bleaching  event,  with  about  80%  of   corals  80%  affected  across  the  colony  surface.    This  site  also  showed  a  strong  response  to   the  2010  bleaching  event  with  about  60%  of  corals  bleached  at  a  low  extent.    Diseases  can   be  high  and  are  dominated  by  dark  spots  disease.    Old  partial  mortality  increased  after  the   2005  bleaching  event  and  then  declined,  with  a  slight  increase  from  2009  to  2011.    Recent   partial  mortality  is  common  at  the  Magens  Bay  site,  largely  as  the  result  of  biting  by   territorial  damselfish  (Stegastes  spp.;  data  not  shown).     Figure  151.    Magens  Bay.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   MAGENS  BAY       236     Figure  152.    Magens  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     237     Fish  Community.  Magens  Bay  once  supported  its  own  rich  fishery  and  was  the  notorious  site   of  the  only  fatality  by  shark  attack  recorded  in  St.  Thomas.  The  days  of  large,  commercially   important  fish  in  Magens  Bay  have  been  gone  since  the  1970’s;  however,  the  bay  is   connected  to  the  deeper  Puerto  Rican  shelf  to  the  north  and  large  sharks  are  known  to   occur  seasonally  in  the  bay.  Tiger  sharks  are  still  caught  commonly  off  either  point  defining   the  bay  to  the  east  or  west.  Anecdotally,  hammerheads  mate  in  the  middle  of  Magens  Bay   during  one  moon  phase  of  the  year,  and  along  the  mile  long  sandy  beach  it  is  not  uncommon   to  see  young  of  the  year  sharks  swimming  in  the  clear  water,  suggesting  that  the  deep   protected  bay  is  the  pupping  ground  for  at  least  one  species  of  shark.  Along  the  reef  that  is   the  TCRMP  monitoring  site,  large  fish  are  rare,  and  herbivores  make  up  the  bulk  of  the  fish   biomass.  The  largest  fish  swim  along  the  reef  edge,  where  occasional  mahogany  and  lane   snapper  can  be  seen,  along  with  grunts,  goatfish  and  larger  parrotfishes.  Schools  of  wrasse,   mixed  with  juvenile  parrotfish  and  damselfish  occupy  the  top  of  the  reef.  The  threespot   damselfish  is  extremely  prolific.  No  large  groupers  or  snappers  were  observed  in  Magens   Bay  in  2012,  the  first  year  of  fish  monitoring.       MAGENS  BAY       238     Herbivores stoplight parrotfish redband parrotfish threespot damsel striped parrotfish doctorfish princess parrotfish dusky damsel queen parrotfish blue tang yellowtail damsel Beaugregory cocoa damsel ocean surgeonfish redtail parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 Invertivores French grunt red hind Caesar grunt blackbar soldierfish yellow goatfish yellowhead wrasse tomtate bluestriped grunt lane snapper squirrelfish slippery dick clown wrasse reef croaker yellowbelly hamlet dusky squirrelfish yellowtail hamlet checkered puffer Spanish hogfish harlequin bass Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 Planktivores yellowtail snapper Fish Biomass (g) 0 200 400 600 800 Piscivores bar jack trumpetfish schoolmaster graysby mahogany snapper black hamlet Fish Biomass (g) 0 200 400 600 800 1000 SITE  SUMMARIES     239   SAVANA  ISLAND   Descrip(on.    The  Savana  Island  site  is  a   midshelf  fringing  reef  facing  the  Atlantic   Ocean  to  the  northwest  in  depths  of  5  –   17  m.    The  reef  is  a  well-­‐developed  coral   community  atop  bedrock,  with  some   insipient  carbonate  accumulation.   Savana  has  been  monitored  since  2003,   with  permanent  benthic  transects   installed  in  2007.   Outstanding  Feature.    Savana  harbors   behemoth  colonies  of  boulder  star  coral   (Orbicella  faveolata)  and  a  diverse  and   abundant  fish  community.   Threats.    Savana  is  threatened  by   warming  ocean  temperatures,  as  O.  faveolata  can  be  susceptible  to  bleaching,  disease,  and   partial  mortality.     The  area  is  also   open  to  fishing  and   the  occasional   accumulation  of   debris  can  be  seen.   Figure  153.    Savana.   (top)  Location.     (right)    A   representative  photo   of  the  reef  during  the   2005  coral  bleaching   event.    The  dog   snapper  Lutjanus   jocu)  is   approximately  50cm   in  length.     SAVANA  ISLAND         240   Figure  154.    Savana  benthic  temperature  record  (10m  depth).     Physical  Characteris.cs.       Current.    Currents  have  not  been  measured  directly  at  Savana.    Strong  unidirectional   currents  can  influence  the  surface  near  the  site.    Wave-­‐driven  oscillatory  currents  are   common  and  occasionally  strong.       Temperature.    Savana  has  temperatures  cooler  than  other  shallow  sites,  likely  due  to  the   proximity  of  the  open  Atlantic  Ocean.       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     241     Benthic  Community.  Boulder  star  corals,  predominately  large  (>2m  wide)  colonies  of   Orbicella  faveolata,  dominate  the  coral  community  at  the  Savana  monitoring  site.    The  site   lost  45.2%  of  its  coral  cover  in  the  2005  bleaching  event.    Some  of  the  largest  losses   occurred  between  2010  and  2011,  but  there  was  no  indication  of  the  cause,  since  the  site   bleached  moderately  and  no  disease  outbreaks  were  noted.    Gorgonians  and  sponges  are   also  prominent  components  of  the  sessile  epibenthic  animal  community.   Coral  Health.    The  coral  community  at  Savana  was  highly  affected  in  the  2005  bleaching   event,  with  80%  of  corals  affected  on  almost  90%  of  the  colony  surface.    Bleaching  was  also   very  prominent  in  2006,  but  at  a  lower  extent.    Bleaching  was  moderate  during  the  2010   bleaching  event,  with  over  50%  of  colonies  bleached  at  a  low  extent.    Coral  diseases  can   reach  high  prevalence  and  are  diversely  represented.    Particularly  noticeable  is  the   dramatic  outbreak  of  white  disease  in  2006.    Dark  spots  disease  has  also  affected  a  high   proportion  of  corals  from  2008  onwards.    Old  partial  mortality  increased  markedly  after  the   2005  coral  bleaching  event  and  has  declined  only  slightly.    Recent  partial  mortality  after  the   2005  coral  bleaching  event  was  unprecedented  for  any  site.    Recent  mortality  has  also  been   common  after  2007  and  is  largely  caused  by  bites  from  territorial  damselfish  (Stegastes   spp.).     Figure  155.    Savana  Island.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.       SAVANA  ISLAND         242     Figure  156.    Savana  Island  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     243   Fish  Community.  The  Savana  Island  fish  community  is  fairly  small  in  biomass,  but  is  quite   diverse,  and  highlights  the  variety  of  benthic  resources  available  to  fishes  in  the  area.  The   site  is  dominated  by  herbivores,  but  it  also  supports  a  diverse  invertivore  community.   Planktivores  in  the  quiet  protected  bay  are  limited  to  the  smaller  pomocentrids  and   wrasses,  however  these  fish  groups  are  all  quite  prolific.  The  most  numerous  piscivore   observed  in  the  first  year  of  fish  monitoring  was  the  schoolmaster  snapper.  One  small   yellowmouth  grouper  (11-­‐20  cm)  was  observed  on  a  belt  transect,  the  first  seen  on  a  site  in   shallow  water  located  near  land.  The  area  around  Savana  is  highly  fished  with  fish  traps,   and  no  large  commercially  important  fish  were  seen  in  the  bay.         SAVANA  ISLAND         244     Herbivores stoplight parrotfish princess parrotfish ocean surgeonfish blue tang striped parrotfish redband parrotfish queen parrotfish redfin parrotfish yellowtail damsel dusky damsel doctorfish threespot damsel Beaugregory cocoa damsel orangespotted filefish Fish Biomass (g) 0 1000 2000 3000 4000 5000 Invertivores bluestriped grunt yellow goatfish Spanish hogfish porkfish spotted goatfish French grunt blackbar soldierfish yellowhead wrasse Caesar grunt saucereye porgy striped grunt puddingwife spotted drum smallmouth grunt fairy basselet dusky squirrelfish slippery dick harlequin bass shy hamlet yellowtail hamlet butter hamlet clown wrasse Fish Biomass (g) 0 200 400 600 800 1000 1200 1400 1600 Planktivores blue chromis creole wrasse bicolor damsel brown chromis Fish Biomass (g) 0 200 400 600 800 1000 Piscivores schoolmaster trumpetfish sand diver graysby bar jack yellowmouth grouper black hamlet Fish Biomass (g) 0 200 400 600 800 1000 1200 1400 SITE  SUMMARIES     245   SEAHORSE  COTTAGE  SHOAL   Descrip(on.    The  Seahorse  Cottage  Shoal   site  is  a  large  patch  reef  surrounded  by   sand  and  rhodolith  in  depths  of  17  –   23m.    The  isolated  reef  is  flat  topped   and  dominated  by  the  Orbicella  spp..   Seahorse  has  been  monitored  since   2003,  with  permanent  benthic  transects   installed  in  2007.    A  ciguatera  study   with  monthly  sampling  has  been   ongoing  since  2009.   Outstanding  Feature.    Seahorse  supports   a  diverse  and  abundant  coral  and  fish   community  adjacent  to  the  St.  Thomas   East  End  Reserves.   Threats.    Seahorse  is  buffered  from  land-­‐based  sources  of  pollution.    The  site  is  a  targeted   site  in  the  St.  Thomas  trap  fishery  and  trap  strings  have  been  observed  over  and  adjacent  to   the  site.         Figure  157.    Seahorse   Cottage  Shoal.  (top)  Location.   (right)    A  representative   photo  of  the  reef.       SEAHORSE  COTTAGE  SHOAL         246   Figure  158.    Seahorse  benthic  temperature  record  (21m  depth).     Physical  Characteris.cs.       Current.    Currents  have  not  been  directly  measured  at  Seahorse  Cottage  Shoal.     Unidirectional  benthic  currents  tend  to  be  slow  and  wave-­‐driven  oscillatory  currents  only   occur  during  heavy  storm  activity.     Temperature.    Benthic  temperatures  are  moderate  to  high  during  warming  events.       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     247     Benthic  Community.  The  coral  community  of  the  Seahorse  site  is  dominated  by  the  boulder   star  coral  (Orbicella  spp.),  but  hosts  a  high  diversity  of  other  coral  species.    The  site  lost   46.6%  of  its  cover  in  the  2005  bleaching  event  and  had  only  regained  4.7%  of  this  loss  by   2011.    Gorgonians  and  sponges  are  also  common  components  of  the  sessile  epibenthic   animal  community.    The  algal  community  is  co-­‐dominated  by  epilithic  algae  and  the   macroalgae  Lobophora  variegata  and  Dictyota  spp..   Coral  Health.    The  coral  community  bleached  severely  in  the  2005  bleaching  event  with   nearly  100%  of  corals  bleaching  over  about  100%  of  their  surface.    Bleaching  prevalence   after  2005  was  slow  to  decline  due  to  delayed  recovery  in  large  Orbicella  spp.  colonies.    The   site  also  had  a  high  prevalence  of  bleaching  in  the  2010  event,  but  at  a  low  extent  on   colonies.    Bleaching  was  also  moderately  prevalent  in  2011.    Coral  diseases  are  common   and  diverse  at  Seahorse.    White  disease  was  also  prevalent  in  2004,  which  is  rare  for  a  site   at  this  depth.    Dark  spots  disease  is  also  ubiquitous.    Old  partial  mortality  increased  to  a   very  high  prevalence  after  the  2005  bleaching  event,  but  had  declined  to  2011.     Figure  159.    Seahorse  Cottage  Shoal.  (left)  Relative  composition  of  the  sessile  epibenthic  animal   community.    (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   SEAHORSE  COTTAGE  SHOAL         248     Figure  160.    Seahorse  Cottage  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     249     Fish  Community.    Seahorse  Cottage  Shoal  supports  a  large  variety  of  reef  fish  and  hosts   spawning  aggregations  of  gray  snapper  and  lane  snapper  during  the  summer  months.    The   trophic  guilds  on  the  offshore  reef  are  split  relatively  evenly  between  herbivores,   invertivores,  and  piscivores.    This  reflects  the  heterogeneity  of  reef  substrate  and  the   availability  of  unconsolidated  sand  and  rhodolith  habitat  surrounding  the  reef.    Mutton   snapper  and  queen  triggerfish  are  relatively  common.    Adult  stoplight  and  redband   parrotfish  dominate  the  herbivores,  although  most  of  the  larger  parrotfish  species  do  occur,   including  the  juvenile  phase.    Glasseye  snapper  and  graysby  dominate  piscivores.    Large   groupers  are  never  seen  on  the  reef.    Seahorse  Cottage  Shoal  is  well  known  to  fishermen   and  fairly  heavily  fished.    Traps  on  the  reef  are  common  during  surveys.    However,   schoolmaster,  lane,  gray  and  mahogany  snapper  are  all  common.    This  may  reflect  the   proximity  to  nursery  habitats  in  the  St.  Thomas  East  End  Reserves  and  the  mangrove   habitats  therein.    Planktivores  are  limited  nearly  entirely  to  yellowtail  snapper.       SEAHORSE  COTTAGE  SHOAL         250   Figure  161.    The  Seahorse  Cottage  Shoal  fish  community  by  absolute  and  relative  biomass. Herbivores stoplight parrotfish redband parrotfish striped parrotfish princess parrotfish orangespotted filefish queen parrotfish doctorfish blue tang yellowtail damsel threespot damsel redfin parrotfish ocean surgeonfish Beaugregory dusky damsel greenblotch parrotfish Fish Biomass (g) 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Invertivores queen trigger sailors choice tomtate French grunt blackbar soldierfish yellow goatfish yellowhead wrasse Spanish hogfish red hind bluestriped grunt squirrelfish shy hamlet clown wrasse harlequin bass yellowbelly hamlet spotted goatfish butter hamlet fairy basselet striped grunt slippery dick Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 7000 Planktivores creole wrasse blue chromis bicolor damsel yellowtail snapper brown chromis tobaccofish Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 Piscivores blue runner bar jack glasseye snapper mahogany snapper schoolmaster graysby gray snapper sand diver trumpetfish spotted moray red lionfish Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 7000 SITE  SUMMARIES     251   SOUTH  CAPELLA   Descrip(on.    The  South  Capella  site  is   located  on  a  rise  of  the  St.  Thomas-­‐St.   John  midshelf  reef  complex  in  depths  of   16  -­‐  25m.    The  reef  is  made  of  rolling   ridges  of  coral  and  pavement   interspersed  with  sand  grooves.    South   Capella  has  been  monitored  since  2003,   with  permanent  benthic  transects   installed  in  2007.   Outstanding  Feature.    The  South  Capella   site  is  part  of  an  outstanding  shallow   water  midshelf  reef  system  that  is   essential  fish  habitat.   Threats.    The  St.  Thomas  trap  fishery  heavily  targets  South  Capella.    Active  and  derelict  trap   strings  crisscross  the  site  and  a  derelict  trap  appeared  in  permanent  transect  1  in  2008  and   has  been  degrading  there  since.    The  trap  was  still  fully  intact  as  of  2012  but  open  to  fish   passage.    The  reef  was   also  highly  affected  by  the   2005  coral  bleaching   event,  suggesting  a   susceptibility  to  rising  sea   surface  temperatures.   Figure  162.    South  Capella.   (top)  Location.    (right)    A   representative  photo  of  the   reef.     SOUTH  CAPELLA       252   Figure  163.    South  Capella  benthic  temperature  record  (24m  depth).     Physical  Characteris.cs.       Current.    Currents  have  not  yet  been  directly  measured  at  South  Capella.    Wave-­‐driven   oscillatory  currents  have  not  been  experienced  but  are  likely  during  swells  and  storms.     Unidirectional  benthic  currents  are  usually  weak,  but  strong  currents  can  develop  from  the   surface  to  midwater.     Temperature.    South  Capella  has  relatively  cool  benthic  temperatures  for  a  shallow  site   during  warm  years,  which  may  be  a  reflection  of  its  moderately  deep  depth  and  proximity   to  deep  water  to  the  south.       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     253     Benthic  Community.    Boulder  star  corals  (Orbicella  spp.)  dominate  the  coral  community  at   South  Capella.    These  corals  were  very  heavily  affected  by  mortality  due  to  the  2005  coral   bleaching  event,  and  the  site  lost  56.4%  of  its  cover  and  had  not  regained  any  cover  by  2011   (-­‐3.7%  recovery).    Gorgonians  and  sponges  are  also  common  components  of  the  sessile   epibenthic  animal  community.    The  macroalga  Lobophora  variegata  dominates  the  algal   community,  with  epilithic  algae  and  Dictyota  spp.  comprising  the  second  largest  shares.     There  was  also  a  high  abundance  of  crustose  coralline  algae  and  filamentous  cyanobacteria.   Coral  Health.    Corals  were  moderately-­‐heavily  affected  by  the  2005  bleaching  event,  with  a   prevalence  of  80%,  but  an  extent  on  colonies  of  only  about  50%.    Bleaching  prevalence  also   increased  during  the  2010  bleaching  event,  but  at  a  low  extent.    Bleaching  is  moderately   prevalent  at  this  site  even  in  years  without  notable  thermal  stress.    Coral  diseases  are   common  and  diverse  at  South  Capella.    White  disease  was  prevalent  after  the  2005   bleaching  event  in  2006,  and  then  again  in  2009  and  2011.    Black  band  disease  was  found   in  2002,  which  is  unusual  for  a  site  at  these  depths.    Dark  spots  disease  was  also  typically   present  in  most  years.    Old  partial  mortality  increased  after  the  2005  bleaching  event  and   has  declined  to  2011.    Recent  partial  mortality  was  prevalent  in  most  years  of  monitoring,   particularly  in  2006.    In  years  not  following  thermal  stress  the  highest  identifiable  source  of   recent  partial  mortality  was  biting  from  territorial  damselfish  (Stegastes  spp.).   Figure  164.    South  Capella.  (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   SOUTH  CAPELLA       254     Figure  165.    South  Capella  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     255   Fish  Community.    South  Capella  is  characterized  by  a  fairly  diverse  fish  community  that  is   usually  fairly  well  split  between  trophic  groups.    The  reef  is  spur  and  groove  with  complex   reef  edge  and  sand  channels  that  supports  a  large  number  of  invertivores  and  variety  of   omnivores.    Planktivores  are  limited  nearly  entirely  to  yellowtail  snapper.  Herbivores  are   dominated  in  biomass  by  striped  and  princess  parrotfish.    The  South  Capella  reef  is  highly   fished  and  traps  are  commonly  seen  during  our  survey  events.    The  complex  reef  is   noticeably  bare  of  large  snappers  and  groupers;  piscivores  are  dominated  by  the  graysby.   Lionfish  are  quite  common,  even  though  the  site  is  highly  fished.         SOUTH  CAPELLA       256   Figure  166.    The  South  Capella  fish  community  by  absolute  and  relative  biomass. Herbivores striped parrotfish princess parrotfish stoplight parrotfish doctorfish redband parrotfish blue tang ocean surgeonfish redfin parrotfish queen parrotfish yellowtail damsel Beaugregory threespot damsel Fish Biomass (g) 0 1000 2000 3000 4000 5000 6000 7000 Invertivores saucereye porgy queen trigger red hind spotted goatfish tomtate French grunt yellowhead wrasse longsnout butterflyfish fairy basselet harlequin bass Spanish hogfish yellowbelly hamlet yellowtail hamlet striped grunt clown wrasse Fish Biomass (g) 0 1000 2000 3000 4000 Planktivores blue chromis bicolor damsel brown chromis creole wrasse yellowtail snapper chalk bass tobaccofish Fish Biomass (g) 0 200 400 600 800 1000 Piscivores graysby great barracuda bar jack trumpetfish gray snapper green moray black hamlet Fish Biomass (g) 0 500 1000 1500 2000 2500 SITE  SUMMARIES     257   SOUTH  WATER   Descrip(on.    South  Water  is  a   hardbottom  coral  community  along  the   sharp  break  of  a  midshelf  reef  complex   in  depths  of  17  –  28m.    The  reef  has  a   sharp  break  in  slope  leading  to  a  steep   escarpment  that  terminates  in  a   sand/sediment  plain  at  the  reef  base.   South  Water  has  been  monitored  since   2005,  with  permanent  benthic  transects   installed  in  2007.   Outstanding  Feature.    South  Water  is  a   commercially  important  fishing  ground   for  reef  fishes  and  spiny  lobster.   Threats.    South  Water  is  primarily  threatened  by  fishing  and  strings  of  fish  and  lobster  traps   are  common  over  the  site.               Figure  167.South  Water.   (top)  Location.    (right)    A   representative  photo  of  the   reef.       SOUTH  WATER       258   Figure  168.    South  Water  benthic  temperature  record  (24m  depth)     Physical  Characteris.cs.       Current.    Current  measurements  have  not  been  taken  at  the  South  Water  site.     Unidirectional  benthic  currents  can  be  moderate  on  the  hardbottom  reef  top  and  strong   from  the  surface  to  midwater.    Wave-­‐driven  oscillatory  currents  are  likely  to  be  felt  on  the   reef  top  during  swells  and  storms.       Temperature.    South  Water  has  relatively  moderate  temperatures  compared  with  other   shallow  water  sites  during  warm  years.    This  may  be  due  to  the  deeper  depths  of  the  site   and  the  proximity  of  deep  water.       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     259     Benthic  Community.  The  sparse  coral  community  at  South  Water  is  very  diverse.    Coral   cover  increased  by  21.3%  over  the  2005  bleaching  event  and  had  increased  by  42.6%   between  2005  and  2011.    However,  permanent  transects  were  not  installed  until  2007  and   the  low  coral  cover  means  that  small  variations  in  detection  of  corals  can  lead  to  large   apparent  year-­‐to-­‐year  differences  in  cover.    Sponges  and  gorgonians  dominate  the  sessile   epibenthic  animal  community.    The  algal  community  is  nearly  equally  divided  between   Lobophora  variegata,  Dictyota  spp.,  and  epilithic  algae.    Crustose  coralline  algae  and   filamentous  cyanobacteria  are  also  very  common.   Coral  Health.    Corals  were  severely  affected  by  the  2005  coral  bleaching  event,  with  over   80%  of  corals  bleaching  over  nearly  the  entire  coral  surface.    Corals  were  moderately   affected  in  the  2010  bleaching  event,  with  just  less  than  50%  of  corals  bleaching  at  a  low   extent.    Bleaching  tends  to  be  moderately  prevalent  even  in  non-­‐thermal  stress  years.    Coral   diseases  are  not  common,  although  there  is  a  trend  of  increasing  dark  spots  disease.    Old   partial  mortality  increased  in  prevalence  after  the  2005  bleaching  event,  but  at  a   prevalence  lower  than  most  other  sites.    Recent  partial    mortality  is  rare.     Figure  169.    South  Water.    (left)  Relative  composition  of  the  sessile  epibenthic  animal  community.     (right)  Relative  composition  of  the  algal  community  and  unconsolidated  sediment.   SOUTH  WATER       260     Figure  170.    South  Water  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     261     Fish  Community.    South  Water  Island  is  a  low  lying  reef  with  hard  bottom  that  supports   primarily  invertivores.    Fish  biomass  is  lower  on  this  site  than  other  offshore  St.  Thomas   sites.    Invertivore  biomass  is  dominated  by  queen  trigger  and  red  hind.    Mutton  snapper  are   occasional.    Stoplight  and  princess  parrotfish  dominate  herbivores,  and  many  juvenile  and   sub-­‐adults  of  these  species  occur  on  the  site.    Piscivores  make  up  only  5%  of  the  biomass  on   the  South  Water  Island  site,  primarily  composed  of  the  graysby.    South  Water  Island  is   highly  fished  and  traps  are  commonly  seen  during  our  survey  events.  Except  for  mutton   snapper,  the  reef  is  bare  of  large  snappers  and  groupers.    Lionfish  (Pterois  volitans)  are  very   common  on  this  site.         SOUTH  WATER       262   Figure  171.    The  South  Water  fish  community  by  absolute  and  relative  biomass. 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 (g) 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 (g) 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 (g) 0 1000 2000 3000 4000 Piscivores dog snapper great barracuda bar jack trumpetfish spotted moray glasseye snapper graysby black hamlet Fish Biomass (g) 0 1000 2000 3000 4000 5000