**Lessons learned from the 2005 Caribbean Bleaching Event**

**Summary of NOAA Bleaching response Workshop, St. Croix, USVI**

**January 24-25, 2006**

**Purpose**

In response to the 2005 Caribbean bleaching event, NOAA's Coral Reef
Conservation Program, NOAA Coral Reef Watch, and the Nature Conservancy
hosted a workshop in St. Croix to discuss preliminary results of efforts
to assess bleaching and mortality.

**Participants**

Thirty-five scientists and managers attended this workshop (please see
Appendix A). Ten researchers presented their findings from Puerto Rico,
the U.S. Virgin Islands, the British Virgin Islands, Martinique, and
Barbados.

**Results**

The speakers reported on 15 separate surveys, at 82 sites: 10 in
Barbados, 25 in the British Virgin Islands, 9 in Martinique, 21 in
Puerto Rico, and 17 in the US Virgin Islands. While methodologies
differed, most surveys used transects (line, belt, and/or video) while a
few surveys focused on tagging individual colonies.

Nine of the 15 surveys, or 60%, reported quantitative bleaching data;
the others had only qualitative bleaching information, or were focused
solely on recent mortality. Of those that did measure bleaching, two
different kinds of data were reported: four measured the percent of the
total coral cover bleached, and six measured the percentage of coral
colonies bleached (see Table 1). The two methods yielded different
results: bleaching ranged from 0 to 90% for percent cover (mean 72%),
and from 25 to 95% for percent of colonies (mean 54%). In one Puerto
Rico survey, data are provided relative to both cover and colonies. The
inability to pool and directly compare results from these two different
methodologies requires that these two parts of the dataset be considered
separately in detecting regional patterns or site-specific differences.

Some of the bleaching surveys stratified their sampling design by reef
type (fringing, shelf edge, island-associated, etc.), by depth, and by
species. There was some indication that bleaching was less severe in
areas of high energy and areas further from shore. Bleaching was
documented across the depth range, from surface to 45 meters. The most
frequently bleached taxa were *Montastraea* spp., *Agaricia* spp., and
*Acropora palmata*.

Nine of the 15 surveys (60%) reported data on recent mortality, but
again methodology varied (Table 1). Surveys measuring percent of coral
cover and percent of coral colonies with recent mortality yielded
similar results: recent mortality ranged from 1 to 34% for percent cover
and from 0 to 35% for percent of colonies.

None of the presentations included quantitative disease data before and
after the bleaching event. Three reported qualitative disease
information, and one reported quantitative info; but conclusions about
whether the bleaching led to higher disease incidence cannot be drawn at
this time.

  ------------ -------------- ------------- --------- ------------- ---------- --------------- ------------- -------------
  **Reported   **Location**   **Survey      **Depth   **Bleaching   **Mean     **Genera most   **Mortality   **Range of
  by**                        type**        (m)**     measure**     bleached   frequently      measure**     mortality**
                                                                    (%)**      bleached**                    

  Ginsburg     Barbados       transect:                                                        \% cover      0.8 -11.6%
                              line/belt                                                                      

  Gore         BVI            tagged                  %colonies     20         *Agaricia*      \% colonies   23%
                              colonies                                                                       

  Gore         BVI            point count   10 - 30   %colonies     60                                       

  Gore         BVI: Guana     transect:                                                        \# colonies   169 - 279
               Island         belt                                                                           

  Gore         BVI: north     tagged                  qualitative              only *A.        qualitative   
                              colonies                                         palmata*                      

  Ginsburg     BVI: south     transect:                                                        \% cover      4.4 - 11.4%
                              line/belt                                                                      

  Gore         BVI: south     transect:                                                        \% cover      8.1 - 33.6%
                              line                                                                           

  Ginsburg     Martinique     transect:                                                        \% cover      2.2 - 14.1%
                              line/belt                                                                      

  Marechal     Martinique     transect:               %cover        75         *Montastraea,                 
                              line                                             Porites*                      

  Hernandez    Puerto Rico:   transect:     0 - 45    %colonies     72                         \% colonies   0 - 32%
               east           video/fixed                                                                    

  Bruckner     Puerto Rico:   transect:     0.5 - 20  %cover        73         *Agaricia,                    
               west           belt                                             Millepora*                    

  Bruckner     Puerto Rico:   transect:     0.5 - 20  %colonies     65         *Agaricia,      \% colonies   1.8 - 15.4%
               west           belt                                             Millepora*                    

  Jeffrey      USVI: St.      transect:               %cover        53         *Agaricia*                    
               Croix          line                                                                           

  Miller       USVI: St. John transect:               %cover        85                                       
                              video                                                                          

  Muller       USVI: St. John tagged                  %colonies     47         only *A.                      
                              colonies                                         palmata*                      

  Smith        USVI: St.      transect:     6 - 40    %colonies     70                         \% colonies   0 - 35%
               Thos./St. John line                                                                           
  ------------ -------------- ------------- --------- ------------- ---------- --------------- ------------- -------------

**Table 1:** Location, transect type, depth, bleaching measure, percent
bleached, genera most frequently bleached, mortality measure, and range
of mortality for each survey presented at the St. Croix meeting.

**Observations and Recommendations**

While most of the regularly monitored sites in Puerto Rico and the U.S.
Virgin Islands were sampled during or shortly after the bleaching event,
some remote locations in Puerto Rico were not sampled. Survey coverage
in other Caribbean island-nations was variable and based on available
funding and personnel. In order to understand the long-term effects of
bleaching on a regional scale, it is critical to fund pre- and
post-bleaching surveys at international and remote locations and to
train local divers to assess the immediate effects of bleaching. One
mechanism to fill spatial and temporal gaps and to complement regular
monitoring programs is to provide training materials to Caribbean dive
operators and enlist them after a bleaching event. Another solution may
be to sample 'representative' bleaching sites instead of trying to
sampling all sites.

In 2005, it was difficult to mobilize Federal funds to initiate a rapid
response to this major bleaching event, except in areas such as National
Parks that had trained staff on hand. Localized meetings that include
representatives from federal and jurisdictional agencies, research and
academic institutions, and non-governmental organizations would be one
way to increase collaboration and initiate a quicker response.
Establishing a rollover fund to respond to catastrophes or forming rapid
response teams, like the CDHC (Coral Disease and Health Consortium) has
established for disease response, may be possible solutions. Local
environmental agencies responsible for monitoring coral reefs should
draft response plans outlining the geographical responsibilities of each
researcher/field team and develop a plan of action (from funding to
field activities to outputs) before bleaching occurs again. Participants
from the U.S. Virgin Islands and Puerto Rico are committed to meet, form
regional teams, and draft response plans. Ideally, these plans could be
shared with other Caribbean nations that do not have established
monitoring programs or staff, to help them prepare and to foster
regional cooperation. Designing monitoring programs that are stratified
and provide comparable results are vital to our understanding of
large-scale bleaching events such as this one.

Major research questions after any massive bleaching event include: how
many corals bleached, how many died, and what species were most
affected? Initial analyses by NOAA's Coral Reef Watch show that the
percent of coral cover bleached is significantly related to maximum DHW
(degree heating weeks) and yields higher statistical power than the
percent of colonies bleached (Figure 1).

![](media/image1.png){width="3.25in" height="2.1666666666666665in"}

**Figure 1:** Preliminary analysis (as of the time of the workshop) of
the mean percent of (a) coral colonies bleached and (b) coral cover
bleached versus the maximum Degree Heating Weeks (DHW) averaged over
nine Caribbean jurisdictions. These data were compiled by NOAA's Coral
Reef Watch from over 700 coral reef surveys in the wider Caribbean. A
more comprehensive set of surveys will be analyzed subsequent to the
workshop.

We recommend that surveys begin before the maximum DHW (degree heating
weeks) is reached, continue during and after the peak DHW and for up to
8 months after bleaching to assess long-term recovery and mortality.
Some longer-term questions include:

-   What are the effects of bleaching on reproduction/spawning?

-   Is disease associated with bleaching and how are bleaching and
    disease related?

-   How does thermal stress affect corals physiologically?

-   How do depth and morphology influence bleaching, recovery, and
    mortality?

-   What are the overall ecosystem effects, such as the cascading
    effects on other organisms including fisheries?

-   What is the annual rate of coral loss due to bleaching and disease?

-   What are the economic impacts of bleaching?

Many of the questions/issues raised point to resource needs and a
commitment from federal and local agencies to fund bleaching surveys.
The U.S. should take advantage of existing international networks and
organizations, such as IUCN (International Union for the Conservation of
Nature and Natural Resource), ICRAN (International Coral Reef Action
Network), GCRMN (Global Coral Reef Monitoring Network), AMLC
(Association of Marine Laboratories of the Caribbean), AGRRA (Atlantic
and Gulf Rapid Reef Assessment), and CARICOMP (Caribbean Coastal Marine
Productivity Program) to increase spatial coverage and coordination of
monitoring efforts. At the same time, these organizations need to
develop plans and be flexible in their sampling to capture events such
as this one. As one change to current practice, organizations that lack
the resources to respond to events such as bleaching should consider
moving their regular sampling to include observations during the peak
bleaching season.

Managers are concerned that the major cause of bleaching, sea surface
temperature, is outside of their local control. This was one of the
major reasons that bleaching was not chosen as one of NOAA's Local
Action Strategies in the U.S. Caribbean. Scientific information on the
compounding effects of other stressors (e.g. sedimentation) and the
cascading effects of bleaching (e.g. loss of fishery habitat) could help
managers minimize local impacts and educate the public. However, it has
become clear that sea surface temperature is an international issue and
managers can only control local activities, such as delaying a
development project during a bleaching event. Conversely, knowledge of
bleaching likelihood could influence the management of local activities.
The U.S. Coral Reef Task Force could consider initiating a bleaching
resolution similar to the spawning resolution of 2005 that includes
bleaching considerations when issuing permits in order to minimize local
impacts. Finally, the anticipated Reef Manager\'s Guide to Coral
Bleaching (NOAA/EPA/GBRMPA/DOI) and other outreach tools will be useful
to managers.

Researchers are continuing to monitor the long-term impacts of the 2005
bleaching event. Current mortality in some reef areas exceeds 20%. This
is a significant amount of mortality. NOAA and other federal agencies
will provide an update on the impacts at the May 2006 U.S. Coral Reef
Task Force (CRTF) meeting, and a comprehensive report at the October
2006 CRTF meeting in the USVI. Puerto Rico and the U.S. Virgin Islands
plan to present their draft response plans at the fall U.S. Coral Reef
Task Force meeting. Coral reef scientists and managers are planning a
special session on this bleaching event at the International Tropical
Marine Ecosystems Management Symposium in October 2005 in Cozumel,
Mexico, along with related sessions on bleaching and management. Other
outputs include a scientific paper summarizing the regional patterns of
coral bleaching and mortality (led by NOAA's Coral Reef Watch) and a
potential special issue of the journal *Coral Reef*s.

We want to thank the 35 participants of the St. Croix meeting for their
valuable input and continued coordination on monitoring Caribbean coral
reefs. If you have any questions, please contact Shauna Slingsby
(<shauna.slingsby@noaa.gov>) or Mark Eakin (<mark.eakin@noaa.gov>).

Appendix A

  -------------- ------------------ --------------------------------------------------------------------------------------------------------- ------------------------
  **Location**   **Name**           **E-mail**                                                                                                **Affiliation**

  St. Thomas     Elizabeth Ban      [[eban@uvi.edu]{.underline}](mailto:eban@uvi.edu)                                                         University of the Virgin
                                                                                                                                              Islands, IOOS

  NESDIS         Eric Bayler        [[eric.bayler@noaa.gov]{.underline}](mailto:eric.bayler@noaa.gov)                                         NOAA Oceanic Research &
                                                                                                                                              Applications Div.

  St. John       Rafe Boulon        [[Rafe_Boulon@nps.gov]{.underline}](mailto:Rafe_Boulon@nps.gov)                                           National Park Service

  NOAA Corals    Andy Bruckner      [[Andy.Bruckner@noaa.gov]{.underline}](mailto:Andy.Bruckner@noaa.gov)                                     NOAA Coral Reef
                                                                                                                                              Conservation Program

  TNC            James Byrne        [[jbyrne@tnc.org]{.underline}](mailto:jbyrne@tnc.org)                                                     The Nature Conservancy

  NESDIS         Tyler Christensen  [[Tyler.Christensen@noaa.gov]{.underline}](mailto:Tyler.Christensen@noaa.gov)                             NOAA Coral Reef Watch

  St. Croix      Chris Crawford     [[crawford.christopher@vidpnr-dep.org]{.underline}](mailto:crawford.christopher@vidpnr-dep.org)           USVI DPNR Dept. of
                                                                                                                                              Environmental Protection

  St. Croix      Susan Curtis       [[susan.curtis@viczmp.com]{.underline}](mailto:susan.curtis@viczmp.com)                                   USVI DPNR Coastal Zone
                                                                                                                                              Management

  TNC            Mark Drew          [[MDrew@tnc.org]{.underline}](mailto:MDrew@tnc.org)                                                       The Nature Conservancy

  NESDIS         Mark Eakin         [[Mark.Eakin@noaa.gov]{.underline}](mailto:Mark.Eakin@noaa.gov)                                           NOAA Coral Reef Watch

  AOML           Louis Florit       [[Louis.Florit@noaa.gov]{.underline}](mailto:Louis.Florit@noaa.gov)                                       NOAA Coral Health and
                                                                                                                                              Monitoring Program

  Puerto Rico    Reni Garcia        [[renigar@caribe.net]{.underline}](mailto:renigar@caribe.net)                                             Puerto Rico Coral Reef
                                                                                                                                              Monitoring Program

  Florida        Bob Ginsburg       [[rginsburg@rsmas.miami.edu]{.underline}](mailto:rginsburg@rsmas.miami.edu)                               University of
                                                                                                                                              Miami/AGGRA

  BVI            Shannon Gore       [[sd_gore@yahoo.com]{.underline}](mailto:sd_gore@yahoo.com)                                               BVI Conservation &
                                                                                                                                              Fisheries Dept.

  NASA           Liane S. Guild     [[Liane.S.Guild@nasa.gov]{.underline}](mailto:Liane.S.Guild@nasa.gov)                                     NASA Ames Research
                                                                                                                                              Center

  AOML           Jim Hendee         [[Jim.Hendee@noaa.gov]{.underline}](mailto:Jim.Hendee@noaa.gov)                                           NOAA Coral Health and
                                                                                                                                              Monitoring Program

  Puerto Rico    Edwin Hernandez    [[coral_giac@yahoo.com]{.underline}](mailto:coral_giac@yahoo.com)                                         University of Puerto
                                                                                                                                              Rico

  St. Croix      Zandy Hillis-Starr [[Zandy_Hillis-Starr@nps.gov]{.underline}](mailto:Zandy_Hillis-Starr@nps.gov)                             National Park Service

  St. Croix      Aaron Hutchins     [[hutchins.aaron@vidpnr-dep.org]{.underline}](mailto:hutchins.aaron@vidpnr-dep.org)                       USVI DPNR Environmental
                                                                                                                                              Protection Division

  NOAA Corals    Chris Jeffrey      [[Chris.Jeffrey@noaa.gov]{.underline}](mailto:Chris.Jeffrey@noaa.gov)                                     NOAA NOS Biogeography
                                                                                                                                              Program

  St. Croix      Conrad E. Knowles  [[conrad.knowles@viczmp.com]{.underline}](mailto:conrad.knowles@viczmp.com)                               USVI DPNR Coastal Zone
                                                                                                                                              Management

  Puerto Rico    Craig Lilyestrom   [[craig@caribe.net]{.underline}](mailto:craig@caribe.net)                                                 PR DNER Fish and
                                                                                                                                              Wildlife

  St. Croix      Alan Luce          [[aluce@tnc.org]{.underline}](mailto:aluce@tnc.org)                                                       The Nature Conservancy

  St. Croix      Ian Lundgren       [[ian_lundgren@nps.gov]{.underline}](mailto:ian_lundgren@nps.gov)                                         National Park Service

  Martinique     Jean-Philippe      [[ommm@wanadoo.fr]{.underline}](mailto:ommm@wanadoo.fr)                                                   Observatoire du Milieu
                 Maréchal                                                                                                                     Marin Martiniquais

  St. Croix      Phillipe A. Mayor  [[pmayor@oceanconservancy.org]{.underline}](mailto:pmayortoc@oceanconservancy.org)                        The Ocean Conservancy

  St. John       Jeff Miller        [[William_J_Miller@nps.gov]{.underline}](mailto:William_J_Miller@nps.gov)                                 National Park Service

  St. John       Erinn Muller       [[EMuller@usgs.gov]{.underline}](mailto:WMuller@usgs.gov)                                                 US Geological Survey

  BVI            Rozina Norris      [[terrozy@yahoo.com]{.underline}](mailto:terrozy@yahoo.com)                                               BVI Conservation &
                                                                                                                                              Fisheries Dept.

  TNC            Shona Paterson     [[spaterson@tnc.org]{.underline}](mailto:spaterson@tnc.org)                                               The Nature Conservancy

  BVI            Orville S. Phillip [[OPhillip@email.hlscc.edu.vg]{.underline}](mailto:OPhillip@email.hlscc.edu.vg)                           H. Lavity Stoutt
                                                                                                                                              Community College

  St. Croix      Paige Rothenberger [[Paige.Rothenberger@viczmp.com]{.underline}](mailto:Paige.Rothenberger@viczmp.com)                       USVI DPNR Coastal Zone
                                                                                                                                              Management

  Puerto Rico    Idelfonso Ruiz     [[idelfonso_ruiz@yahoo.com]{.underline}](mailto:idelfonso_ruiz@yahoo.com)                                 University of Puerto
                                                                                                                                              Rico

  NESDIS         William Skirving   [[William.Skirving@noaa.gov]{.underline}](mailto:William.Skirving@noaa.gov)                               NOAA Coral Reef Watch

  NOAA Corals    Shauna Slingsby    [[Shauna.Slingsby@noaa.gov]{.underline}](mailto:Shauna.Slingsby@noaa.gov)                                 NOAA Coral Reef
                                                                                                                                              Conservation Program

  St. Thomas     Tyler Smith        [[tsmith@rsmas.miami.edu]{.underline}](mailto:tsmith@rsmas.miami.edu)                                     University of the Virgin
                                                                                                                                              Islands

  NESDIS         Al Strong          [[Alan.E.Strong@noaa.gov]{.underline}](mailto:Alan.E.Strong@noaa.gov)                                     NOAA Coral Reef Watch

  St. Croix      Marcia Taylor      [[mtaylor@uvi.edu]{.underline}](mailto:mtaylor@uvi.edu)                                                   University of the Virgin
                                                                                                                                              Islands

  St. Croix      Wes Toller         [[westoller@vipowernet.net]{.underline}](mailto:westoller@vipowernet.net)                                 USVI DPNR Fish and
                                                                                                                                              Wildlife

  St. Croix      Henry E.           [[go7seas@hotmail.com]{.underline}](mailto:go7seas@hotmail.com)                                           Independent/National
                 Tonnemacher                                                                                                                  Park Service

  St. Croix      Violeta            [[villanueva-mayor.violeta@vidpnr-dep.org]{.underline}](mailto:villanueva-mayor.violeta@vidpnr-dep.org)   USVI DPNR Dept. of
                 Villanueva-Mayor                                                                                                             Environmental Protection

  St. John       Rob Waara          [[Rob_Waara@nps.gov]{.underline}](mailto:Rob_Waara@nps.gov)                                               National Park Service

  BVI            Nancy K. Woodfield [[nkwoodfield@yahoo.com]{.underline}](mailto:nkwoodfield@yahoo.com)                                       BVI National Parks Trust
  -------------- ------------------ --------------------------------------------------------------------------------------------------------- ------------------------