This may be Goniopora savignyi. Although one of the most common of the Goniopora species at Kwajalein, it is rather nondescript and often overlooked. In fact we had no photos of it by itself in its normal brown to gray coloration, but had to crop down some general coral scenery shots to get the first four photos below. Its abundance was made evident when all the colonies bleached in the fall of 2009 when the water temperature peaked at 30°C, less than a degree above its usual high of about 29°C. This species, if all the photos below are indeed the same, is (or was) common on lagoon, pinnacle and seaward reefs.
Below, the coral is starting to bleach white by expelling its symbiotic zooxanthellae with rising water temperature.
It is apparent that this Goniopora species is particularly sensitive to warm water, and was one of the first corals to turn white. The abundance of this coral was clear when all the colonies bleached snow white in September, 2009, the first time we saw this happening at Kwajalein. The 2009 bleaching was followed by warm water coral bleaching episodes in 2013, 2014, 2016 and especially 2018. Most of the colonies that bleached in 2009 died, and most of the survivors were killed off in the subsequent bleachings. By 2017, it was getting hard to find living colonies.
These small colonies in a shaded overhang could be another species.
Created 5 December 2020
Updated 2 July 2023