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Coral reefs lecture outline Session 5: Coral Reefs Coastal Hazards Management Course Basic ecology, global distribution, and structure of coral reefs Seagrass beds and Mangrove forests Ecosystem goods and services provided by coral reefs Threats to coral reefs Slide 5.1, Lecture Outline (Courtesy: John Bruno)

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Global distribution of coral reefs Session 5: Coral Reefs Coastal Hazards Management Course Reef-building corals require clear, warm waters, with plenty of light and minimal nutrients Slide 5. 2, Global Distribution of Coral Reefs Global distribution of coral reefs (Courtesy: Elizabeth Selig)

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Biology of corals Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.3, Coral Biology and Morphology A coral colony and a close up image of coral polyps (Courtesy: John Bruno)

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Some examples of tropical coral morphology Session 5: Coral Reefs Coastal Hazards Management Course Slide 5. 4, Coral Morphology Branching corals (Courtesy: John Bruno) Boulder corals (Courtesy: John Bruno)

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Reef zonation: the backreef Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.5, Reef Zonation: the Backreef Aerial photograph of a Mexican reef (Courtesy: Conrad Neumann) the backreef zone A backreef patch reef (Courtesy: Conrad Neumann)

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Reef zonation: the reef crest Session 5: Coral Reefs Coastal Hazards Management Course high energy environment dominated by coralline algae Slide 5.6, Reef Zonation: the ReefCrest A reef crest-note surge channels (Courtesy: Conrad Neumann) A reef crest (Courtesy: Conrad Neumann)

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Reef zonation: the forereef Session 5: Coral Reefs Coastal Hazards Management Course Slide 5. 7, Reef Zonation: the Forereef Elkhorn coral (Courtesy: John Bruno) Staghorn coral (Courtesy: John Bruno)

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Who lives on a reef? Session 5: Coral Reefs Coastal Hazards Management Course Slide 5. 8, Reef Inhabitants Coral reefs are inhabited by thousands of species including: Fish Sea turtles Sharks and rays Urchins and star fish Worms Crabs and lobster Snails Clams, scallops, and barnacles Sea slugs Algae Sponges Soft corals

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Seagrass beds Session 5: Coral Reefs Coastal Hazards Management Course Slide 5. 9, Seagrass Beds A backreef seagrass bed (Courtesy: John Bruno)

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Mangrove forests Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.10, Mangrove Forests A mangrove forest (Courtesy: John Bruno)

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Ecosystem goods and services provided by reefs Session 5: Coral Reefs Coastal Hazards Management Course Storm buffers Tourism $1.6 billion/year in the Florida Keys $8.9 billion/year in the Caribbean Fishing Coral reef fisheries account for: 10% of fish harvest in tropical countries 25% of fish catch in developing countries 90% of protein consumed by people on Pacific islands Biodiversity and bioprospecting Slide 5.11, Some Examples of Ecosystem Services Provided by Reefs

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Coral reef decline Session 5: Coral Reefs Coastal Hazards Management Course Some of the recent changes to coral reefs: decline in coral cover and reef heterogeneity loss of large vertebrates overexploitation of fish and invertebrates increase in macroalgal cover Slide 5.12, Some of the recent changes in coral reefs A Jamaican reef dominated by macroalgae (Courtesy: John Bruno)

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Caribbean coral reef decline Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.13, Caribbean Reef Decline Case study Meta-analysis of 263 Caribbean sites from 65 studies (Gardener et al. 2003) On average, coral cover in the Caribbean decreased from 60% to 10% over the last 20 years.

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Threats to coral reef health: overfishing Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.14, Overfishing on Coral Reefs A Jamaican fish trap: few large fish remain on the reef and the catch is usually fish more suitable for an aquarium than a dinner plate. (Courtesy: John Bruno)

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Threats to coral reef health: disease outbreaks Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.15, Coral Disease Outbreaks A boulder coral infected with yellow band disease-caused by a bacterial pathogen (Courtesy: John Bruno) A sea fan with aspergillosis-a fungal infection (Courtesy: John Bruno)

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Threats to coral reef health: increasing ocean temperature Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.16, Iincreasing Ocean Temperatures and Coral Bleaching Increases in Caribbean Sea Surface Temperature (Puerto Rico1966-1995) 0.7C increase in 30 years Winter et al. 1998 Severe bleaching events

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Threats to coral reef health: small scale threats Session 5: Coral Reefs Coastal Hazards Management Course anchors ship groundings divers and snorkelers coastal development collecting Slide 5.17, Smaller Scale Threats to Coral Reef Health A snorkeler standing on a coral (Courtesy: Conrad Neumann)

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Mitigating the threats to coral reef health Session 5: Coral Reefs Coastal Hazards Management Course Slide 5.18, Managing Coral Reef Ecosystems Are there any realistic solutions to managing coral reefs? There are several causal factors that operate at different spatial scales. What are some potential management strategies?