Post Tsunami Reef Analysis - Thailand's Andaman coast.
By Paul Foley (prosharks@yahoo.com)
An analysis of the effect of the tsunami on marine resources was co-coordinated by the Department of Coastal and Marine Resources and the Phuket Marine Biological Centre. It was conducted using a standardised methodology by those Thai universities in possession of baseline data.
Number of Thailand diving sites:
Province
No impact
(0%)
Very low impact (1-10%)
Low impact (11-30%)
Medium impact (31-50%)
High impact
(>50%)
Total
Ranong
0
2
2
1
7
12
Phang Nga
21
12
16
10
13
72
- Surin Islands
0
5
7
5
4
21
- Similan Islands
11
7
8
5
7
38
Phuket
12
5
3
1
0
21
Krabi
12
8
4
4
2
30
- Phi Phi Islands
5
4
3
2
1
15
Trang
2
4
2
0
0
8
Satun
22
5
3
0
1
31
Special thanks to Dr Niphon Phongsuwan.
A survey conducted by the Phuket Dive Operators Club of Thailand, focusing only on acknowledged Thailand dive sites, found corresponding data: 73% of diver's reefs suffered little to no damage.
Analysis
Reef damage is considerably less than might be expected and was initially reported, given the coastal damage.
As on land, significant damage is extremely localised.
Fish stocks appear intact, and are probably benefiting from the reduced fishing effort.
Exposed shallow fringing reefs suffered as one might expect.
Coral with delicate and intricate structures such as gorgonian fans were most susceptible to impact. The flexibility of some soft corals appears to have been a survival advantage.
Damage otherwise followed no obviously discernable pattern, often being counter-intuitive, e.g. at the northern end of the Similans despite the wave coming from the south west.
Surin and Similan Islands no. 9 (Breakfast Bend, Snapper Alley, Hideaway) suffered most of the serious damage.
Several of the heavily damaged sites are still considered dive-able, with abundant fish life, noticeably Koh Tachai, and North Point on Similan Island No. 9.
Famous Thailand scuba diving sites such as Shark Point in Phuket, Richelieu Rock, Hin Daeng, and Fantasy Reef are untouched.
The reefs of Myanmar appear completely unscathed. The massive coral structures of the Burma Banks are still the Andaman region's outstanding coral attraction.
Conclusions
Although there are naturally concerns about the smothering effect of displaced sediment and physical damage upon reefs and other fish nursery grounds, the author feels these to be misplaced. Those of us who have dived on tsunami hit reefs before, such as at Maumere - Flores in Indonesia, know that reefs are fully capable of taking such natural events as this in their stride.
Mostly, reefs are capable of withstanding the force of the wave, and where they are not, the reef bounces back in remarkably quick time, with no noticeable detrimental effect upon fish stocks. Indeed generally, the tsunami event may prove to be a positive thing for the health of the reef as a whole, just as forest fires play an important role in reinvigorating the forest ecosystem by allowing a spurt of fresh growth.
This is in contrast to the damage that occurs from pollution, warming, habitat destruction, damaging fishing practices, and over-fishing: We remind all that these insidious dangers are the real issues needing address so as to maintain the health of the reef ecosystems we love.
Paul Foley
Paul Foley is an independent professional conservationist working largely with the scuba diving industry, and focusing on:
Marine protected area networks: design, management and enforcement
Shark finning campaigns and policy
Effects of climate change upon marine life
Over-fishing, illegal fishing, by-catch
Building a constituency for marine conservation
He played an integral role in the establishment of no shark fishing zones in Myanmar, and international protection of the great white shark and Napoleon wrasse through CITES.