Effect of extreme oceanic events in the coral formations of Islas del Rosario, Colombian Caribbean

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The increase in frequency and intensity of extreme oceanic events limits the capacity of recoveryof ecosystems, threatening their subsistence. Thus, in order to understand the relationship between coral healthand extreme environmental events, data on sea temperature, runoff and / or salinity, turbidity were analyzed in theIslas del Rosario in comparison with coral cover, and coral signs of deterioration (e.g., bleaching, coral diseases).In the time series of environmental variables, oceanic events that exceeded a statistical threshold were calculated,establishing their intensity, duration and frequency. The attributes of the community were studied through observations in two stations of the National Coral Reef Monitoring System in Colombia (SIMAC), assessed in two timewindows (long term, 1998-2013 and short term, 2013-2014). The extreme events of sea surface temperature, riverdischarge and associated turbidity, were the main variables related to the reduction of coral cover. The massivecoral bleaching of 2005 and other subsequent events resulted in a reduction in coral coverage between 2004 and2010. During the short-term observations there were no strong extreme events or changes in coral formations,although thermal stress and reductions in salinity in the rainy season were associated with a slight bleaching inNovember 2014. Although the signs of deterioration are low, it is important to consider them, since the synergybetween continuous disturbances can lead to a loss of coral cover.