Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005

Coral Reef Watch, National Oceanic and Atmospheric Administration, Silver Spring, Maryland, USA.
PLoS ONE (Impact Factor: 3.53). 11/2010; 5(11):e13969. DOI: 10.1371/journal.pone.0013969
Source: PubMed

ABSTRACT The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin.
Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles.
Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.

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Available from: Michael James C Crabbe, Jul 20, 2015
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    • "Anomalously warm water temperatures have been observed to be one of the major causes of mass coral bleaching worldwide (Munday et al., 2009; Eakin et al., 2010). Critical water temperatures (30–31 • C), duration extent (hours, days, or weeks) and event intensity (Berkelmans and Willis, 1999; Craig et al., 2001; Vargas-Angel et al., 2001; Berkelmans, 2002; Sammarco et al., 2006) are all known to affect coral bleaching (Berkelmans and Willis, 1999; Reaser et al., 2000; Eakin et al., 2010; Bastidas et al., 2012). Coral often dies after having been partially or totally bleached for long periods (Crabbe, 2008). "
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    • "Temperature-induced stress has been a key factor in mass mortalities associated with bleaching and infectious disease in coral reef organisms (Harvell et al. 1999, 2002, 2009; Hoegh-Guldberg et al. 2007; Carpenter et al. 2008; Croquer & Weil 2009a; McClanahan et al. 2009; Miller et al. 2009; Weil et al. 2009a; Rogers & Muller 2012). Significant warming of the Caribbean basin in the past 25 years (Chollet et al. 2012), including six major thermal anomalies and warmer winters, has coincided with coral bleaching events, disease emergence, and an increasing frequency of infectious disease outbreaks (Weil et al. 2009a, Eakin et al. 2010, Ruiz-Moreno et al. 2012). Similarly, on the Great Barrier Reef, high summer thermal anomalies and mild winter temperatures have been linked to outbreaks of tissue-loss coral diseases (e.g., white syndromes) (Bruno et al. 2007, Heron et al. 2010, Maynard et al. 2011). "
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    Annual Review of Marine Science 01/2014; DOI:10.1146/annurev-marine-010213-135029 · 16.38 Impact Factor
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    • "The DHW scale ranges from 0.0 to 16.0 degreeweeks , when DHW values are greater than 1, sporadic coral bleaching is likely to occur. By the time DHW values reach 8, widespread bleaching is likely and some mortality can be expected (Goreau et al., 2000; Wellington et al., 2001; Strong et al., 2004; Coral Reef Watch, 2003; Liu et al., 2003, 2006; Eakin et al., 2010). According to the CREWS, there are five defined stress levels (Table 2). "
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