GCRMN_COI_2017-Western Indian Ocean Reef Status

Coral reef status report for the Western Indian Ocean (2017)
Global Coral Reef Monitoring Network
a
b
Figure 1.3.7. Overview of the total impact of the 2016 bleaching event in the WIO is shown by
comparing the overall bleaching records up to the end of May, when bleaching had just passed
its peak, to mortality from May onwards, when corals were either recovering or dying. a) all
sites, and b) sites that were surveyed both during peak bleaching phase and re-surveyed during
the post-bleaching phase (n=104). Categories are estimates of percentage coral cover bleached
at a site, and the columns show the proportion of reports in each category. Numbers above the
columns indicate the number of reports.
Between the months of January-May, just over 35% of reported sites were affected by
severe bleaching (greater than 50% of the coral cover had bleached), and only 10% of
sites were unaffected (fig 1.3.7a). However the high and extreme levels of bleaching did
not translate into the same level of coral mortality later in the year (May-September), with
less than 10% of sites reporting severe mortality. This pattern is the same for sites that
were re-surveyed both during and after the bleaching event (fig. 1.3.7b). However, it is
important to note that the region did not survive completely un-scathed with almost 80%
of sites experiencing some mortality due to bleaching.
REGIONAL CHAPTERS
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