Status of Caribbean coral reefs after bleaching and hurricanes in 2005

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Status of Coral Reefs of the Lesser Antilles after the 2005 Coral Bleaching Event%9080706050403020100GuadeloupeMar – Jul 05 Nov – Dec 05 Apr – May 06 Nov – Dec 06Survey Date%%6050403020100706050403020100MartiniqueJul – 05 Dec – 05 Jul – 06 Dec – 06Saint Barthélemy Survey DateFeb – 05 Aug – 05 May – 06 Nov – 06Survey Date% Species bleached% Colonies bleached% Cover bleached% Mortality (% cover lost)The effects of increased sea temperatures on the coral reefs of the French West Indies are presentedin these 3 figures. There was no apparent bleaching by July 2005; but between August and December,there was clear evidence of a major bleaching event with about half of all corals bleached, but fewsigns of mortality. However, by mid-2006, 30% to 40% of the coral cover had died, and more than10% of the remaining corals were bleached.91
Status of Caribbean Coral Reefs after Bleaching and Hurricanes in 2005Observations in June 2007 showed that many corals remained pale or partially bleached andhad not fully recovered their stock of zooxanthellae, despite normal seawater temperatures.The three-dimensional structure of the reefs was apparently not affected by the bleaching; forexample, in 2004, the average number of fish species per 600 m 2 was 45 and the average fishbiomass was 807 kg.ha -1 and by the end of 2006, comparable measures were 48 species and 994kg.ha -1 .Martinique: Bleaching started in August 2005 and the first surveys in December showed thatbleaching affected 51% of coral species, 49% of all coral colonies, and an average of 50% of thesurface area of each colony. Coral mortality was moderate in December with a loss of 11% incoral cover. The number of coral recruits decreased from an average of 49 recruits per 10 m 2 inJuly 2005 to 28 recruits per 10 m 2 in December 2005, even though coral recruitment is usuallygreater in December. Juvenile recruitment was still low in 2006 (32 recruits per 10 m 2 ).Bleaching persisted during 2006 and by the end of the year, 27% of all coral species showedsigns of bleaching and 18% of coral colonies were affected. The average bleached surface areaof corals was 26%. As a consequence of the delayed coral mortality, the average coral cover haddeclined from 28% to 19%. Most of the recently dead corals were colonized by algae, whichincreased cover by 15%. The health of surviving coral colonies was threatened by coral disease,with 49% of colonies showing tissue necrosis and 48% of the colony surface area affected.The fish communities did not appear to be affected: in the 2005 bleaching there was an averageof 46 species per 600 m 2 and fish biomass of 788 kg.ha -1 ; whereas in 2006 there were 44 specieson average and the biomass was 1207 kg.ha -1 .Saint-Barthélemy: Bleaching was recorded first in August 2005 and affected 63% of coralspecies, 48% of colonies, and an average of 54% of the coral cover. No immediate coralmortality was seen. Coral recruit density was the lowest noted during this season, decliningfrom 50 recruits per 10 m 2 to 35 recruits per 10 m 2 . Recruitment of juveniles remained lowin 2006. Throughout 2006, there was delayed coral mortality and by the end of the year coralcommunities showed no signs of recovery, with 40% of coral species, 14% of colonies and anaverage of 20% of the surface of individual colonies still being bleached. By November, the livecoral cover had declined by 40%, from 20% before bleaching to 12% afterwards and the deadcorals were mainly colonized by algae, with cover increasing by 12%.The surviving colonies deteriorated significantly throughout 2006; early in the year, tissuenecrosis on colonies rose from 18% to 23%, and the colony surface area affected increasedfrom 30% to 48%. The number of infected colonies was still high although many had died fromcoral disease. By mid-2007, many corals remained pale or partially bleached and had not totallyrecovered from bleaching, despite normal sea surface temperatures.The average fish species richness on reefs was 48 species per 600 m2 and the fish biomass751 kg.ha -1 before 2005; and 57 species per 600 m 2 and a similar fish biomass of 742 kg.ha -1 in200692
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Stat u s o fCa r i b b e a nCo r a
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Dedication: This book is dedicated
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Status of Caribbean Coral Reefs aft
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Status of Coral Reefs in the Caribb
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3. Hu r r i ca n e s a n d t h e i
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Hurricanes and their Effect on Cora
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Hurricanes and their Effect on Cora
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4. Th e 2005 Bl e a c h i n g Ev e
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Status of Caribbean coral reefs after bleaching and hurricanes in 2005

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