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Grupo Arrecifes del Pacífico de la MEXLTER. Disturbance on coral reefs from the Mexican Pacific.
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Grupo Arrecifes del Pacífico de la MEXLTER Disturbance on coral reefs from the Mexican Pacific
Coral reefs are exposed to recurrent natural disturbances, such as tropical cyclones, outbreaks of the crown of thorns star Acanthaster planci, and coral bleaching caused by El Niño-Southern Oscillation (ENSO) and La Niña Overfishing, pollution and other anthropogenic disturbance can also affect coral community structure.
After the 1982-83 and 1997-98 ENSO events, the recovery of reefs in most eastern Pacific has been slow or nil, with the result that coral framework is suffering severe losses of carbonates by bioerosion; in addition, predation on corals have aggravated the problem as predators population density has not decreased. In the Gulf of California, the bleaching of coral communities observed in 1997 was the most severe ever reported for this region (Reyes Bonilla 2001). Branching corals that dominates at depths of 6 m in the eastern Pacific, was more affected than massive corals that usually occur in deeper areas.
Types of corals Massive Branching
Islas Marietas 2008 bleaching • Last 25 years seawater mean temperature1: 26.31± 0.18 ºC Before May 2008 [1] http://iridl.ldeo.columbia.edu/SOURCES/.NOAA/.NCEP/.EMC/.CMB/.GLOBAL/.Reyn_SmithOIv2/.monthly/.sst/
May 2008 • May 2008 seawater mean temperature: 19.1 ºC • Rapid recovery: 90% of affected corals showed only partial mortality after one month