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BY CHANCE OR BY DESIGN: CAN MARINE RESERVES HELP MANAGERS PROTECT CORAL REEFS FROM “UNMANAGEABLE” STRESSES?. FL Map. Executive Order on Coral Reef Protection 1998—no mention of bleaching 1998 bleaching event shifted the focus from human threats to GCC
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BY CHANCE OR BY DESIGN: CAN MARINE RESERVES HELP MANAGERS PROTECT CORAL REEFS FROM “UNMANAGEABLE” STRESSES?
Executive Order on Coral Reef Protection 1998—no mention of bleaching • 1998 bleaching event shifted the focus from human threats to GCC • USVI--Long-term monitoring of coral reefs in decline from hurricanes, other causes • In USVI, disease > bleaching • VI National Park—top 10 on Endangered Park List
What is needed to better manage coral reefs in the face of changing climate • Can marine reserves help? What role can deeper reefs play? • What are the challenges? • More research on links between disease, bleaching, and human activities
METHODS MATTER • Video transects vs. chain transects • One-time assessments won’t do it • Individual coral colony monitoring • Frequency of sampling
VIDEOGRAPHY • Quantitative data • Selection of random transects • Statistical rigor • Permanent visual record
Newfound Lameshur • PERCENT BLEACHED CORAL • 1998 Newfound 13% chain; 43% video (24% cover) • Lameshur 18% chain; 47% video (10% cover) • 1999 Recovery. No loss of coral cover.
1999 1998 2000 What killed this coral?
Rationale for Monument Creation Smaller size classes, serial depletion of species Commercially extinct species: Nassau Grouper • Over-fishing • Coral Reef Decline
Significant Habitats Gained • Mid-shelf reef living coral cover 4x higher than inshore reefs
Resistance/Resilience of Deeper Reefs • Less vulnerable to bleaching because of their depth (cooler temps., less radiation) • Less disease • Less damage from storms [more with GCC?], anchors, runoff • Source of new larvae? Fecundity? • Species composition—deep vs. shallow
CONCEPTUAL MODEL OF YUKKY REEF RUNOFF STORMS DUST WBD DIADEMA DIE-OFF SEA FAN FUNGUS PLAGUE BBD NO MORE FISH!! Caution: not for navigational purposes!!
Research Needs • Relationship between bleaching and disease (deep reefs less susceptible?) • Link between mortality and bleaching • Can the marine reserves reverse the declines? • Effects of reserves on ecological processes—herbivory and coral recruitment • Fecundity of deep water corals • Reproduction of diseased corals (reduced?) • Connectivity
CONCLUSIONS • Marine reserves have potential to offset bleaching and disease • Increased herbivory---- recruitment • Fewer other stresses