Bleaching in Vietnam

[Susan Wells]

This is a small observation to add to the depressing list of sites affected
by bleaching in Asia.  I have just come back from Vietnam where I saw
major bleaching on reefs in the Con Dao Islands, which lie about about
200 km south of Ho Chi Minh City (Saigon)  and 80 km off the Mekong
Delta.  I dived at 2 sites (to a maximum depth of about 15m) and
snorkelled at 3 other sites.  At all localities there was extensive bleaching
(I would estimate over 70% - considerably worse than my only other
experience of a major bleaching event which was Belize in 1995), at all
depths and in most species.  Some of the bleached colonies were
already being overgrown by algae.  The water was noticeably warm. 

The reefs had some of the most impressive coral growth that I have
seen for sometime, but had already been badly damaged by Typhoon
Linda in November 1997.  Con Dao National Park was established as an
MPA in 1991, and WWF-Indochina has been working on a turtle
conservation project there since 1995.  Currently WWF and HK
University of Science and Technology are collaborating on a
DANIDA-funded Marine Biodiversity Project to provide training and advice
to park staff on how to manage the park.

I also dived twice at Hon Mun Island (further north, off the coast at Nha
Trang), the site of a proposed marine protected area.  Here, I observed
no bleaching and the water was noticeably cold, apparently due to a
well documented adjacent upwelling.

I snorkelled very briefly in Halong Bay (right in the north of the country)
and did not observe any bleaching here, although I only saw a small area
of reef.  Much of Halong Bay is a World Heritage Site.

I would urge anyone going to Vietnam to contact the National Institute of
Oceanography (at Nha Trang), the WWF-Indochina office (in Hanoi) or
Con Dao National Park if they are able to help check the situation out in
more detail.

Sue Wells
Marine Programme Co-ordinator
WWF International
Switzerland