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Les:
<BR>I have stitched together some text (below) related to a bleaching and
mortality event that resulted from extreme hot weather in the summer of
1996 in the western Arabian Gulf (western Indo-Pacific, sort of).
At the time I was impressed with the manner in which Acropora mortality
occurred. Our experience suggests that if there was 100 percent
bleaching, the result was 100 percent mortality (by tissue sloughing -
more elgantly, exfoliation) of an Acropora colony - bleached Acropora tissues
simply never recover. Now, after reading your posting, I wonder whether
<BR>we should not be using another term (besides bleaching) to describe
the response of Acropora to extreme temperatures.
<BR>I am not familiar with the literature on "white plague" (is that casued
by pathogens?). What is "polarized coral death" ?
<BR>Does Acropora in the Caribbean ever recover from bleaching ?
I have seen reports of Acropora bleaching in the GBR, but I do not know
whether that resulted in mortality.
<P>Yusef Fadlallah
<BR>Research Institute
<BR>King Fahd University
<BR>Dhahran 31261
<BR>Saudi Arabia
<BR>
<BR>
<P>In the summer of 1996, nearshore seawater temperature held
<BR>between 33.5 and 37 C for approximately 90 days along
<BR>the Saudi Gulf coast and elsewhere in the Gulf (postings
<BR>to the list by Jan Corrubel, Roger Uwate, and Yusef Fadlalla)..
<BR>As a result, there was widespread multispecific bleaching in
<BR>nearshore coral communities, and an outbreak of Black Band
<BR>Disease (BBD) in the Acroporas of one reef, with catastrophic
<BR>consequences for Acropora, and Stylophora pistillata (where found).
<BR><B>Coral</B> <B>mortality followed rapidly. Acropora colonies
that bleached</B>
<BR><B>lost tissue in a random process, as coral tissue sloughed off</B>
<BR><B> in a haphazard manner from all areas of a colony or</B>
<BR><B>different locations on the same branch. In contrast, BBD affected</B>
<BR><B>Acropora lost tissue as the black bands progressed in an even</B>
<BR><B>pace from the bases of branches to the tips.</B>
<BR><B>Both processes resulted in catastrophic losses (estimated at</B>
<BR><B>over 95% of colonies of Acropora on many reefs). Stylophora</B>
<BR><B>pistallata mortality was not characterized by the "tissue sloughing"</B>
<BR><B>that was observed in Acropora.</B>
<BR>
<P>Les Kaufman wrote:
<BLOCKQUOTE TYPE=CITE>I would be very grateful if anyone could bring to
my attention observations
<BR>of Pacific acroporids exhibiting conditions resembling white plague
(the
<BR>one with tissue exfoliation and polarized coral death) in the tropical
west
<BR>Atlantic acroporids.
<P>Les Kaufman
<BR>Boston University Marine Program
<BR>Department of Biology
<BR>Boston University
<BR>5 Cummington Street
<BR>Boston, MA 02215
<P>e-mail: lesk@bio.bu.edu
<BR>phone: 617-353-5560
<BR>fax: 617-353-6340
<P>"I believe we are on an irreversible trend toward more freedom and
<BR>democracy... but that could change."
<P>-Vice President Dan Quayle, 5/22/89</BLOCKQUOTE>
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