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Status of Caribbean coral reefs after bleaching and hurricanes in 2005

Status of Caribbean coral reefs after bleaching and hurricanes in 2005

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<strong>Status</strong> <strong>of</strong> Coral Reefs <strong>of</strong> the Lesser Antilles <strong>after</strong> the <strong>2005</strong> Coral Bleach<strong>in</strong>g EventIn 1996, there were 28 <strong>coral</strong> species on the Saba Bank, with 60-90% <strong>coral</strong> cover. However,AGRRA surveys <strong>in</strong> December 1999 recorded only 24% <strong>coral</strong> cover with the highest cover at 21m depth, <strong>and</strong> 27.5% dead <strong>coral</strong> cover. This <strong>in</strong>dicated that disease <strong>and</strong> <strong>bleach<strong>in</strong>g</strong> had severelydamaged these shallower <strong>reefs</strong>.There is limited fish<strong>in</strong>g around Saba <strong>and</strong> fish populations are considered healthy, but stillrecover<strong>in</strong>g from historical over-fish<strong>in</strong>g. Grouper <strong>and</strong> snapper biomass cont<strong>in</strong>ues to rise <strong>after</strong>the establishment <strong>of</strong> the Saba National Mar<strong>in</strong>e Park. About 50 fishers (mostly from Saba) fishon the Saba Bank target<strong>in</strong>g ma<strong>in</strong>ly lobsters, red snapper <strong>and</strong> conch. There was an <strong>in</strong>tensivegrouper fishery until populations decl<strong>in</strong>ed.St. Eustatius: The <strong>of</strong>fshore <strong>reefs</strong> beg<strong>in</strong> at 25 m depth with complex spur <strong>and</strong> groove formationsthat extend to 60 m. There are steep buttresses on the northern part with 80% <strong>coral</strong> cover<strong>and</strong> 35 species. The northern complex has a labyr<strong>in</strong>th <strong>of</strong> encrusted ridges, s<strong>and</strong> channels <strong>and</strong>huge encrusted rocks, with a fr<strong>in</strong>g<strong>in</strong>g reef on the exposed Atlantic side. The leeward side ismostly a s<strong>and</strong>y plateau with large populations <strong>of</strong> Queen Conch down to 17 m. Hurricanes Luis<strong>and</strong> Marilyn (1995) removed large amounts <strong>of</strong> sediment from the erod<strong>in</strong>g cliffs <strong>and</strong> severelydamaged s<strong>of</strong>t <strong>coral</strong>s <strong>and</strong> sponges; recovery was rapid.There are only 15 full- or part-time fishers on St. Eustatius, who use traps to catch fish <strong>and</strong>lobsters for restaurants. Yellowtail snapper <strong>and</strong> grouper are highly prized, but locals eatalmost any reef fish. Spear-fish<strong>in</strong>g with scuba is illegal, but is still practiced. Many conch werecollected until 2001, when regulations were enforced, but some are still taken illegally. Conchpopulations appear healthy, <strong>and</strong> turtles are protected, although some poach<strong>in</strong>g <strong>of</strong> eggs stilloccurs despite an <strong>in</strong>tensive public awareness campaign.St. Maarten: Patch <strong>reefs</strong> with spur <strong>and</strong> groove structures at 8-18 m depth are concentratednear the east <strong>and</strong> south-eastern part. In 1999, average hard <strong>coral</strong> cover was about 30% with<strong>bleach<strong>in</strong>g</strong> <strong>and</strong> some diseased <strong>coral</strong>s evident. Hurricane Luis damaged <strong>reefs</strong>, seagrass beds <strong>and</strong>beaches, <strong>and</strong> re-suspended s<strong>and</strong> smothered Acropora palmata st<strong>and</strong>s <strong>in</strong> shallow water, butthese have largely recovered.There are about 30 fishers who use fish traps <strong>and</strong> other artisanal practices. Fish populationsare still reasonable, although big groupers are uncommon <strong>and</strong> conch populations have beendepleted.Effects o f t h e <strong>2005</strong> Bl e a c h i n g Ev e n tCoral <strong>bleach<strong>in</strong>g</strong> was first noticed <strong>in</strong> the north on St. Maarten, Saba, <strong>and</strong> St. Eustatius <strong>in</strong> lateAugust <strong>2005</strong> <strong>and</strong> cont<strong>in</strong>ued until mid-November <strong>2005</strong>. Around 80% <strong>of</strong> <strong>coral</strong> colonies werebleached on these isl<strong>and</strong>s <strong>in</strong> mid-October. Coral loss on St. Eustatius from June <strong>2005</strong> to June2006 was 18% at 15 m depth (<strong>coral</strong> cover dropped from 24% to 6%) <strong>and</strong> 11% at 25 m (from26% to 15%). No mortality data are available for St. Maarten <strong>and</strong> Saba.Bleach<strong>in</strong>g was less common on Bonaire <strong>and</strong> Curaçao, with <strong>bleach<strong>in</strong>g</strong> affect<strong>in</strong>g an average <strong>of</strong>14% <strong>of</strong> <strong>coral</strong> colonies dur<strong>in</strong>g November <strong>2005</strong>. No mortality was apparent <strong>and</strong> average <strong>coral</strong>cover rema<strong>in</strong>ed at around 40% at 12 m depth <strong>and</strong> 30% at 6 m, between April <strong>2005</strong> <strong>and</strong> April2006.95

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