responses of mixed coral assemblages to bleaching

[Clare Bradshaw]

Dear Paul and Coral-List,

On our two trips (1998, 1999) to the southern Seychelles that I mentioned in a previous posting, we
also saw clear differences in the timing and long-term impact of bleaching on different coral types:

1.  In March/April 1998, the vast majority of branching corals (mainly Pocillopora and Acropora) and
Heliopora/Millepora were already bleached or dead.  In April 1999, they were almost all dead.
2.  In 1998, all the soft corals (Lobophytum, Sarcophyton, Sinularia) we saw were either bleached,
or dead and disintegrating.  In around 100 hours underwater in 1999 we saw less than 10 colonies (at
three different islands).
3.  In 1998, a lower % (but still in the order of 50%) of massive corals bleached, but in 1999 it
seemed that many of these hade survived.  So, like Paul Marshall's observations, these types took
longer to respond and were less impacted in the long run.
4.  Encrusting corals showed the lowest incidence of bleaching in 1998, and the lowest mortality in
1999.

Some 1998 data is presented in our recent paper - Spencer T et al (2000) Marine Pollution Bulletin
40(7):569-586
You can also come and hear more details in Bali!

Clare Bradshaw
(and Kristian Teleki, Mark Spalding, Tom Spencer)

--
Dr Clare Bradshaw
Port Erin Marine Laboratory
University of Liverpool
Isle of Man
IM9 6JA
British Isles

tel: +44 1624 831017
fax: +44 1624 831001