Presentation on theme: "BY CHANCE OR BY DESIGN: CAN MARINE RESERVES HELP MANAGERS PROTECT CORAL REEFS FROM “UNMANAGEABLE” STRESSES?"— Presentation transcript:
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
White Pox— elkhorn coral
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
Aqua-Map ™ Sonar-based Mapping System
Newfound PERCENT BLEACHED CORAL 1998 Newfound 13% chain; 43% video (24% cover) 1998 Lameshur 18% chain; 47% video (10% cover) 1999 Recovery. No loss of coral cover. Lameshur
What killed this coral?
Rationale for Monument Creation Over-fishing Over-fishing Smaller size classes, serial depletion of speciesSmaller size classes, serial depletion of species Commercially extinct species: Nassau GrouperCommercially extinct species: Nassau Grouper Coral Reef Decline
Significant Habitats Gained Mid-shelf reef Mid-shelf reef living coral cover 4x higher than inshore reefs
What is in the new monuments?
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 REEF MODEL
WBD STORMS DIADEMA DIE-OFF SEA FAN FUNGUS PLAGUE BBD DUST NO MORE FISH!! CONCEPTUAL MODEL OF YUKKY REEF RUNOFF 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