http://ourworld.compuserve.com/homepages/ mccarty_and_peters/coral/C-intro.htm Threats to  Coral Reefs http://tools.coralreef.org/content/ objects/view.acs?object_id=545
Importance of Coral Reefs 0.2% of world’s oceans Habitat for 1/3 of marine fishes Habitat for tens of thousands of other animals The rainforests of the oceans
Importance of Coral Reefs PROTECTION TO COASTLINES ECONOMIC RESOURCES BIODIVERSITY NATURAL BEAUTY
Importance of Coral Reefs PROTECTION TO COASTLINES absorb energy of ocean waves reduce erosion  of shoreline storm damage flooding
Importance of Coral Reefs ECONOMIC RESOURCES  Fisheries for food Fisheries for jobs Tourism Building materials Aquarium trade
Importance of Coral Reefs BIODIVERSITY The rainforests of the sea Genetic diversity Pharmaceuticals
Importance of Coral Reefs NATURAL BEAUTY http://sustainableseas.noaa.gov/missions/ florida2/background/coralspawning.html
$375 billion in environmental goods and services Reefs at Risk 1998 (http://www.wri.org/powerpoints/reefswww/sld011.htm
Caribbean reef values (annual net benefits in 2000) Fisheries: $310 million Dive tourism: $2.1 billion Shoreline protection: $0.7-2.2 billion Total: $4.1-4.6 billion
REEFS WORLDWIDE ARE THREATENED 11% of reefs have been lost 16% of reefs severely damaged ~60% of studied reefs threatened by human activities No pristine reefs left
CARIBBEAN REEFS DECLINING 1970s: ~50% coral cover Present: ~10% coral cover =80% reduction in coral cover over last 30 years Gardner et al. 2003 Science 301: 958-960
Threats to coral and coral reefs: 1) Natural  2) Anthropogenic  of human origin
Natural disturbances that affect corals and coral reefs? Hurricanes Tsunamis Volcanoes Earthquakes Predators & competitors Bleaching Pathogens
Hurricanes Physical damage http://www.nhc.noaa.gov/ 1989hugo.html Destruction of other ecosystems upon  which coral reefs depend Freshwater poisoning Smothering
Tsunamis Physical damage  Possible disruption of  reproduction and recruitment Erosion
Volcanoes Depends upon where volcano occurs http://volcano.und.nodak.edu/vwdocs/ current_volcs/montserrat/montserrat.html smothering and  sedimentation Heat
Earthquakes Little direct impact  coastal  landslides Indirect impacts triggers tsunamis
Predators crown of thorns starfish  snails parrotfish butterflyfish http://www.aims.gov.au/pages/reflib/ cot-starfish/pages/cot-q07.html http://www.sanctuaries.nos.noaa.gov/pgallery/pgflower/living/fg_living.html
Competitors algae http://catbert.er.usgs.gov/african_dust/algae.html
Loss of zooxanthellae causes  higher than usual ocean temperature  sharp changes in salinity heavy  UV  light exposure Bleaching http://ourworld.compuserve.com/homepages/ mccarty_and_peters/coral/Bleach.htm
http://orbit-net.nesdis.noaa.gov/orad/coral_bleaching_index.html
Pathogens Diseases on the rise new pathogens (8+) land pathogens ( Aspergillus ) occurring at all depths More susceptible when stressed http://ourworld.compuserve.com/ homepages/mccarty_and_peters/ coral/Bbd.htm
Threats to coral and coral reefs: 1) Natural  2) Anthropogenic  of human origin
Anthropogenic threats to coral reefs: Overfishing Development Mining and dredging Recreation
Overfishing Ecological imbalance http://tools.coralreef.org/content/objects/view.acs?object_id=545 http://www.photolib.noaa.gov/reef/reef2570.htm
Overfishing Ecological imbalance http://catbert.er.usgs.gov/african_dust/events.html
http://oceanworld.tamu.edu/students/coral/coral5.htm http://www.wri.org/indictrs/rrcyanid.htm Overfishing Destructive fishing practices
Development Sediment    smothering Freshwater input Pollutants & nutrients  (sewage, pesticides, fertilizer, heavy metals, pathogens)
http://www.wcmc.org.uk/marine/data/coral_mangrove/coral.danger.html http://ourworld.compuserve.com/homepages/mccarty_and_peters/coral/c-intro.htm Development
Development http://www.sanctuaries.nos.noaa.gov/scied/science/habitat/influences.html
Mining for construction materials and dredging Destruction of reef structure stirs up sediment
Recreation Anchors, boats, flippers, hands, feet Kill animal tissue  Skeleton breakage http://www.sanctuaries.nos.noaa.gov/scied/science/habitat/influences.html
interaction of natural changes & human activity multiple insults  Synergistic effects
Global climate change Reduced reef building Increase in frequency and intensity of hurricanes Increases in bleaching Increased in disease
CORAL DOMINATED  ALGAL DOMINATED Synergistic effects

Threats to Coral Reefs