[Coral-List] Long term change in Eritrean reefs: past, present, future

[Thomas Goreau]

> Long term change in Eritrean reefs: past, present, future

I'm wondering why this very interesting article on Eritrea's reefs  
just posted on the list server ends with the word "Advertisement"?  
Could that be because every place in the world is advertising their  
reefs as "pristine" to attract tourists, whether that is true or not?

In the early 1960s the late Thomas F. Goreau did a lot of work on  
Eritrean reefs, especially in the Dahlak Arhipelago. To his surprise  
he found the coral cover was very low. That was where he discovered  
the feeding mode of Acanthaster planci, extruding its stomach to  
digest coral tissue, something he had not seen when he collected the  
first live Acanthaster intact at Bikini Atoll in 1947, when they  
lived deep in crevices and only came out to feed at night (they were  
previously known from dredge haul samples and nothing was known of  
their ecology). He attributed the low coral cover he found in Eritrea  
to chronic infestation by Acanthaster swarms. This was long before  
the "first" outbreaks that he, Rick Chesher, and Rick Randall studied  
in the Western Pacific in the late 1960s. I have all the photos and  
scientific specimens, but I have never found anyone interested in  
comparing them to look at long term change.

Now if the report below is correct, and I completely trust Charlie  
Veron''s assessment, this implies that the severe Acanthaster  
predation that was there 4-5 decades ago has disappeared completely  
and permanently? If so, that is truly remarkable, and deserves much  
further work because all across the Indo-Pacific we have been seeing  
recurrent infestations and nobody has any idea how to control them.

It should also be noted that mapping the Bleaching HotSpots (sensu  
Goreau & Hayes, 1994) shows that there should have been several very  
severe bleaching events there in recent decades. I have several times  
alerted researchers in Eritrea to look out for them, but never  
received any field confirmation. The long term sea surface  
temperature trends for Eritrea (which I can supply on request)  
suggest that worse lies ahead since maximum temperatures in this  
region is warming considerably faster than the global ocean average  
(Goreau et al, 2005).

Another interesting point about this article below is that if the  
reefs are so good everywhere in Eritrea, why have the fisheries  
declined? I am one of the scientific advisors to the Manzanar  
Project, which has planted vast mangrove forests along Eritrean  
desert shorelines where no mangroves ever existed, using Gordon  
Sato's innovative approaches, and these have resulted in large  
increases in catches by local fishermen, which would presumably imply  
that the reef fisheries habitat is not as pristine as claimed.

It is delightful to hear that Eritrean reefs are "pristine", but this  
raises very important issues of long term historical changes, and  
almost certainly does not imply immunity to the challenges that  
global warming will throw at them. More work is clearly needed.

> Thomas J. Goreau, PhD
President
Global Coral Reef Alliance
37 Pleasant Street, Cambridge MA 02139
617-864-4226
goreau at bestweb.net
http://www.globalcoral.org

> Message: 3
> Date: Wed, 16 Apr 2008 04:24:46 +0100
> From: "Pete Raines" <psr at coralcay.org>
> Subject: [Coral-List] Eritrea: Coral reefs
> To: <coral-list at coral.aoml.noaa.gov>
> Message-ID: <NIBBLIGNCDPFNHJHDOJDMEMIGIAB.psr at coralcay.org>
> Content-Type: text/plain;	charset="windows-1250"
>
> Dear Listers,
>
> Having spent some time in Eritrea (e.g. as CTA to the UNDP/GEF/GoE- 
> funded
> 'ECMIB Project'), taken at face value I find the following report
> potentially very encouraging and timely:
>
> http://www.weatheronline.co.uk/cgi-app/reports? 
> ARCHIV=0&LANG=en&JJ=2008&MM=0
> 4&TT=15&MENU=Topics&FILE=b1.txt&
>
> Eritrea?s coastal, marine and island area covers more than 121,000  
> km2 of
> the Red Sea and includes more than 350 offshore islands and 1,200  
> km of
> coastline, or 18% of the Red Sea continental coastline.
>
> The BBC recently visited Eritrea to film aspects of Eritrea's  
> unique and
> mostly under researched islands and coral reef systems, for  
> inclusion in
> their forthcoming 'Oceans' series. To the best of my knowledge, Tony
> Backhurst (www.scuba.co.uk) was involved in facilitating this.
>
> Pete
>
> ________________________________________
> Peter Raines MBE FRGS FIBiol CGeog CBiol MInstD
> Founder & CEO
>
> Coral Cay Conservation Ltd
> Elizabeth House, 39 York Road, London, SE1 7NJ, United Kingdom
> Tel: +44 (0)20 7921 0460 (direct line)
> Tel: +44 (0)7925 218 011 (cell phone)
> Tel: +44 (0)20 7620 1411 (switch board)
> Fax: +44 (0)20 7921 0469
> email: psr at coralcay.org
> www.coralcay.org
> skype: peter.raines
>
> Eritrea: Coral reefs
> Hope for global marine future
>
> SHEIKH SEID, Eritrea, April 15, 2008 (AFP) - Silver bubbles pop to  
> the surface as a snorkeler glides over a colourful coral reef,  
> bright fish speeding to safety in its protective fronds. Experts  
> say this small Horn of Africa nation has some of the most pristine  
> coral reefs left anywhere worldwide, a "global hotspot" for marine  
> diversity supporting thousands of species. Known also as Green  
> Island for its thick cover of mangroves, Sheikh Seid is only one of  
> 354 largely uninhabited islands scattered along Eritrea's southern  
> Red Sea desert coast, many part of Eritrea's Dahlak archipelago.  
> The remote reefs are exciting scientists, who see in Eritrea's  
> waters a chance of hope amidst increasingly bleak predictions for  
> the future of coral reefs -- if sea temperatures rise as forecast  
> due to global climate change. Unlike the deeper, cooler waters  
> elsewhere in the Red Sea, Eritrea's large expanses of shallow --  
> and therefore hotter -- waters have created corals uniquely capable  
> of coping with extremes of heat, scientists say. "Eritrea has the  
> most temperature tolerant corals in the world," said marine expert  
> Dr John 'Charlie' Veron, dubbed the "king of coral" for his  
> discovery of more than a fifth of all coral species. "That bodes  
> well, for climate change is set to decimate coral reefs."
>
> Leading scientists warn that most reefs -- vital for the massive  
> levels of marine life that depend upon them and a crucial component  
> of coastal economies -- will be largely extinct by the end of the  
> century unless greenhouse gas emissions are curbed. They say many  
> will be killed by mass "bleaching" and irreversible acidification  
> of seawater caused by the absorption of carbon dioxide into surface  
> waters, with at least 20 per cent of coral reefs worldwide already  
> feared lost. But with Eritrea's surface water in summer an average  
> bathwater temperature of 32.5 C (90.5 F) -- reportedly peaking at a  
> sweltering 37C (98.6 F) -- corals here have evolved to survive in  
> an environment that would kill others elsewhere in the world.
>
> Eritrea's isolation due to long years of bloody war with neighbour  
> Ethiopia, combined with minimal tourist numbers and government  
> efforts to protect the coastline, have left much of the country's  
> extensive coral reefs untouched. "Around most of the world,  
> especially Asian and African coastlines of the Indian Ocean, coral  
> reefs have been plundered in one way or another, the most damaging  
> activity being explosive fishing," added Veron, former chief  
> scientist with the Australian Institute of Marine Science. "The  
> reefs of Eritrea look as if they have been in a time warp -- they  
> have not been touched." On a recent three-week diving expedition  
> along Eritrea's 3,300 kilometres (2,046 miles) of mainland and  
> island coastline, Veron found five species new to science --  
> something the scientist described as "most unusual". "Eritrea  
> probably has the richest suite of corals of the Red Sea, and its  
> 'coral gardens' are in exceptionally good condition," he added.
>
> Such findings have encouraged ambitious plans offering hope for the  
> future of reefs worldwide, with some believing that Eritrea's  
> corals offer a potential nursery for future "re-planting". Alain  
> Jeudy de Grissac, a French marine scientist who has spent the past  
> three years diving along Eritrea's coast, believes small coral buds  
> -- comparable to taking cuttings from plants -- could be placed in  
> areas where coral has died by sea temperature increases. "The coral  
> here is already well accustomed to high temperatures for long  
> periods of time," Jeudy said, a former technical advisor to  
> Eritrea's marine conservation body. "If you seed the coral it would  
> spread out... it would of course take some time, but they could  
> occupy the area left by others." The principle of re-seeding coral,  
> or "ecological restoration", has already proved successful, Jeudy  
> added. "It has already been done in the case of accidents, such as  
> if a ship grounds and the coral is crushed," he said. "Testing  
> would be needed, as this would be a totally new concept for coral  
> reef researchers, but it could be one future of coral survival for  
> many countries." It also offers a potentially lucrative opportunity  
> for tourists. Veron pointed out that just north of Eritrea,  
> visitors to Egypt's Red Sea reefs generate more cash than visitors  
> to its famous archaeological sites. "The Eritrean reefs are a  
> tourist industry gold mine waiting to be opened," Veron said.
>
> Eritrean tourism still has far to go, hampered both by concerns of  
> renewed conflict with Ethiopia, and reports by human rights groups  
> that the military regime is guilty of widespread abuses. However,  
> the government says it is deeply committed to conservation, with Dr  
> Woldai Futur, Eritrea's minister for national development, calling  
> climate change the "most challenging global issue", which, if not  
> addressed, would have "catastrophic consequences". On Sheikh Seid,  
> planned to be Eritrea's first marine protected area, those  
> snorkeling over the reefs are excited by the sights beneath the  
> waves. "The colours are fantastic," one swimmer said, emerging out  
> of the sparkling blue water. "The fish are all around me."
>
> pml/jmm/gh
>
> ADVERTISEMENT