[Coral-List] Evidence for Porites surviving rising ocean temperatures?

[Austin Bowden-Kerby]

Hi Jessica, 
 
From my experience, the genus Porites does in general tend to be quite thermally tolerant, being well adapted to nearshore and lagoonal environments, however many other genera also have thermally tolerant genotypes and/or symbionts.  I suspect that if you had visited that particular reef site within weeks of the bleaching that you would have seen a lot more diversity among the surviving corals- before post bleaching predation sets in.  What I have seen on multiple occasions after severe bleaching is that COTS, coralivorous snails, and other coral predators (which much prefer Acropora and Pocillopora etc. to Porites), tend to quickly wipe out the remaining colonies of their prefered corals when their food supply is suddenly reduced.
 
In my opinion the most effective post-bleaching strategy that can help the reef recover from bleaching and help the reef adapt to the impacts of climate change over the long-haul is to actively remove coral predators from patches of reef post-bleaching.  It may be possible to involve dive operators and resort staff in this activity, in effect creating a small army to help ensure that the thermally tolerant corals survive at least on patches of high value reef.  
 
A parallel strategy would ideally sample fragments of the surviving corals more widely, with the creation of in-situ nurseries of the thermally tolerant corals, and to focus subsequent restoration efforts on these bleaching resistant coral/symbiont genotypes, trimming second generation fragments from the nurseries for replanting to restoration sites.  Please see my recent ICRS paper for more on this topic. 
 
Thanks for your post,
 
Austin 

Austin Bowden-Kerby, PhD
Corals for Conservation
Suva, Fiji (679) 331-3377 
Sustainable Livelihoods Farm (679) 623-1480
Cell (679) 938-6437
www.changemakers.com/node/93448

______________________________________________________________________
FW: Evidence for Porites surviving rising ocean temperatures?
      (Jessica Ward)

Date: Sun, 7 Oct 2012 13:39:02 +0000
From: Jessica Ward <Jessica.Ward at erm.com>
Subject: [Coral-List] FW: Evidence for Porites surviving rising ocean
    temperatures?

Hello Listers.

I just wanted to flag something of interest I noted recently while diving off Phuket.    My husband and I did a series of dives in the area over two days, visiting a site known as 'Shark Point' twice.  Though the local dive masters claimed this was the best site in the area,  we noted that the reef was not in great shape .  In fact, much of the scleractinian coral was dead, with exception of Porites colonies (I think P. lobata).  This interested me  after seeing posts on the List predicting that Porites may survive climate change  and rising ocean temperatures better than other genera of
 scleractinian corals. When we inquired as to what may have happened to kill off the coral, we were told a bleaching event occurred a couple years back.  If this is true, the fact that only Porites (mostly) survived may be evidence of the current theory.  I was curious to know if anyone had any  pre-bleaching information on this or other sites in the area and could compare pre-bleaching verus 
post-bleaching coral cover and species survived?  Would  make for an interesting study .

Cheers.

Jessica C Ward

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