'Blue' coral -Reply

[Jan Korrubel]

Dear fellow coral'lers,

>> Patrick Mitchell-Jones <patmj at cdstecsv.demon.co.uk> wrote:
>>
>> Whilst diving in the Maldives (North Ari Atoll) recently, I 
>> commented on the large number of 'Blue' and Blue tipped' coral 
>> growths which have previously been white/cream. Some appeared to
>> be turning pale blue from the tip downwards, others had patches
>> of blue. 

> Craig Bingman <cbingman at netcom.com> replied:
>
> Host autofluorescent pigments (some of which are blue) are more
> easily observed when the symbiotic dinoflagellate population of the
> coral is reduced, as in "bleaching" from high temperature or high
> irradiance.
>
> This is one possible explaination for the observation.  There may be
> others.

I would be most interested to hear more about this.  While diving in
Sodwana Bay (northern east coast of South Africa) very recently (last
week), we too observed this "blue phenomenon".  As mentioned above,
the blue can be light in colour or very bright, affecting the entire
colony.

In addition to the blue, we also noticed numerous _Porites_ colonies
with a luminescent/flourescent pink border - can this be attributed to
the same phenomenon?

Jan Korrubel
Michael Samways

Invertebrate Conservation Research Center
University of Natal
Pietermaritzburg
South Africa