coral bleaching in Seychelles

coral-list admin jch at aoml.noaa.gov
Tue Sep 19 11:18:04 EDT 2000


Dear Coral-Listers,

My colleague Dr. Al Strong of NOAA/NESDIS recently forwarded the following
message to me from Tim Ecott.  Al forwarded the message to me for comment,
and I wrote back to Tim, as did Dr. Marguerite Toscano (also of NESDIS),
and Tim replied (also attached).  I would very much appreciate it if you
could review this message and offer any comment (to coral-list and/or Tim,
timecott at hotmail.com) you might have to further illustrate the condition
of the reefs in the areas he has mentioned.  [Note: the text of the
messages has been altered somewhat to make it more readable, but none of
the dialogue has been eliminated.]

Many thanks for your thoughts.

=09Cheers,
=09Jim Hendee

Forwarded message
Date: Wed, 6 Sep 2000 12:34:15 -0400
From: tim ecott <timecott at hotmail.com>
To: Al Strong <alan.e.strong at noaa.gov>
Subject: WWW comments (Coral bleaching indice)

I have just returned from Mahe, Seychelles where I dived inshore reefs -
sites which I had previously dived and worked on as a dive leader from
1992-97. I was shocked to find that on some reefs i estimated 95% of the
hard coral to be dead/missing and whole groups of fish also missing or in
much reduced numbers. Parrotfish, angelfish, butterflyfish seemed
particularly low in numbers - sea cucumbers, anemones and other
invertebrates were almost invisible -

The reefs in question were part of the National marine Parks system in
some cases, while others have been severely affected by land reclamation
projects, sewage outfall and reef dredging for building. Authorities in
Seychelles continue to proclaim that the coral reefs are no worse affected
than other reefs around the world. This is untrue. They are virtually
dead.

Deeper offshore sites (30m +) are obviously less affected. Grateful for
any feedback.

tim ecott


Date: Thu, 7 Sep 2000 08:15:02 -0400 (EDT)
From: Jim Hendee <hendee at aoml.noaa.gov>
To: tim ecott <timecott at hotmail.com>
Cc: Al Strong <astrong at nesdis.noaa.gov>
Subject: WWW comments (Coral bleaching indice) (fwd)

Tim,
        We would like to verify the message below and find out more from
you about these observations.  Did you mean to say that instances of hard
coral were actually missing?  Do you feel they were poached (live aquarium
trade), dredged, or what?  Do you by chance have any records of sea
temperature or salinity or other physical factors?  Are the locals
(besides the "authorities" ) aware of this?  Have you reported this to
anyone else?  Do you have more specific information on location, such as
name of reef(s) or latitude and longitude?

        Thanks!

        Cheers,
        Jim Hendee

Forwarded message
Subject: Re: WWW comments (Coral bleaching indice)
Date: Thu, 07 Sep 2000 13:51:24 GMT
From: =93tim ecott=94 <timecott at hotmail.com
To: mtoscano at nesdis.noaa.gov

Dear Marguerite,

Many thanks for your message - I have just given a more detailed reply to
Hendee following an email from him. I will certainly try to get a copy of
Wilkinson=92s report as I am a journalist with BBC World Service and write
on environmental issues when I can. I think Seychelles has been
particularly badly hit by the bleaching aftermath, and the relatively
shallow inshore waters certainly got very warm. The reefs around Mahe are
not large and I know that in general they have not been regarded as very
significant or as particularly exciting examples of species diversity but
having dived in PNG, Fiji, Australia, Red Sea. UK and USA (north and
south) I can say that in fact there was an incredibly wide range of life
on those small reefs and they are now a virtual desert.

tim


Forwarded message
Date: Thu, 07 Sep 2000 13:45:08 GMT
From: tim ecott <timecott at hotmail.com
To: hendee at aoml.noaa.gov
Subject: Re: WWW comments (Coral bleaching indice) (fwd)

Dear Jim,

- It seems that large areas of coral died after belaching and then
collapsed and the rubble has settled into heaps which have now been
colonised by  brown/red algae

- In some places dredging and blasting has taken place - off the east
coast of Mahe for the land reclamation project and on the west coast at
Corsaire Reef where a new jetty has been constructed. There is no cyanide
fishing  that anyone is aware of, nor is there an aquarium trade link as
the transportation facilities are not available.

At this time of year the sea temperature is around 26c (seasonal norm) but
during the =91El Nino=92 period two years ago the sea temperature around Ma=
he
on  the shallow dive sites reached 33c and at times slightly more. In Baie
Ternay there has been pollution from a pig farm on shore which seems to
have caused an infestation of blue/green algae in the marine park on the
east coast siltation from construction and  dredging for new land
reclamation projects has adversely affected the reef.


Species now absent where previously abundant are:

- Magnificent anemones Hectaractis magnifica - one small specimen spotted
on a reef area measuring 100m x 25m where previously there were more than
15 specimens.

- Stichodactyla haddoni - none spotted where previously four known

corals
- Pocillopora eydouxi and verrucosa which had colonised two artificial
reefs (barges sunk in 1988) now not present

- same site - no Acropora cerealis not A. digitifera
- Montipora corals - one or two specimens showing pink and blue and white
ring marks and white patches where there were previously large numbers of
healthy specimens
- west coast - one garden of A formosa stretching 70metres by 10m - all
dead, some buds appearing.
- On all sites there were one or two examples of large Porites - now white=
=20
and covered in algae.
- on all sites some Fungia (simplex and moluccensis) seem to have
survived, all bearing pink patches

- on several sites the only signs of growth are small colonies of Favia
speciosa, and pentagona, stelligera.
- no predominantly live specimens of Platygyra were seen
- no Euphyllia sp. seen
- no Tubipora seen


I am sorry not to be able to give scientific measurements for these areas,
these are all reefs that I have dived dozens of times, and areas that I
grew to know very well. Previously evident molluscs like Spondylus are now
absent, though there seem to be a number of tridacna surviving in
otherwise desolate reef areas - all small.


Fish noticeable by their absence in all but very small numbers were:

-soldierfish (Myripristis adusta and vittata)
- squirrelfish
- Razorfish Aeoliscus strigatus
- Fistularia commersonii

Strangely there were several large specimens of Chinese Grouper on the
reefs (Plectropomus laevis) although my visit concided with a jellyfish
bloom and large numbers of spawn - and there were whalesharks feeding
close inshore.

- Parrotfish were also much reduced, I saw one juvenile (Cetoscarus
bicolor) and a group of five medium sized Bolbometopon in deeper water.
- Butterflyfish - none spotted!

No I haven=92t reported this to anyone else, not officiall but I'=92ve talk=
ed
to local dive businesses and people in environment. The Dept of
Dnvironment in Seychelles is aware of the problem as of course are the
local dive operators. They are very keen not to publicise this information
for fear of losing business.  The Association of Professional Divers in
Seychelles is headed by a dive shop owner who has written several articles
and web tourism articles saying that =93Seychelles is no worse affected tha=
n
many other places in the indian Ocean=94.  At present local dive companies
are using the sites where hard coral used to be healthy as =91last ditch=92
sites for novice divers who don=92t know any better, and taking experienced
divers to the granite sites where there was less hard coral in the first
place, and where the soft corals (mostly Dendronephthya) seem to have
survived quite well. Local divemasters are well aware of the situation,
but general public awareness is very low - as in most tropical islands
most local inhabitants do not dive and are very unaware of species
diversity on the reefs.  Allegedly the situation on the =91outer islands=92=
 is
better, but divers I know who work on Praslin and La Digue say that most
of their inshore reefs are severely affected.  Some divers claim they are
now seeing a recovery of some reefs albeit slow.

I don't have latitude and longitude but the reefs are Fisherman's Cove,
Beau Vallon Bay.. Baie Ternay, and offshore sites such as Brissare Rocks
(large expanse of =91fire=92 coral (Millepora) now showing some signs of
regeneration.

If the Mahe Plateau is a foretaste of what can happen with rising sea
temperatures then the future is very very bleak. I have been profoundly
depressed by what I saw.  Do you have more specific information on
location, such as name of reef(s) or latitude and longitude?

I don=92t know if you have people returning more scientifically gathered
data out there, but I know people who would cooperate in gathering data on
a regular basis and I=92m sure it would be in there interests to help.

tim







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