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Sea Turtle Identification

Here on Koh Tao we are lucky enough to the chance to see Sea Turtles during your diving or snorkelling. There are only 7 different species of Sea Turtle left on the planet and the majority of those species are threatened with extinction.  Here we mainly see the species of Hawksbill and Green Turtle, and so as a community we have started to ID and track our local turtles. 

They have just hit 800 observations on the database which is fantastic and has really helped improve the quality this year. With some of the sightings showing a return of some individuals, a total of over 100 Turtles being recorded around the island.

While undoubtedly Koh Tao is an important location for turtles, we definitely need more input from outside the one little island. While the good news is that the database is growing and our understanding is improving (such as Betty, found by professional videographer Elisabeth Lauwerys as the first resident of Mango Bay in our records).

Unfortunately A quarter of all our Green Turtle recorded were found dead, even more if you include turtles that had to be rescued and/or sent to Chumphorn for hopeful recovery. Emphasizing more and more the importance for recording any sightings. 

By taking a clear picture of the head on both sides, and a picture of the entire turtle, using a algarythim for the scutes on the face and combining that with any clear marking on the shell. The individual can be recorded in to database, as a new or returning individual.

We then add the pictures to the Koh Tao Turtle Facebook page, from there they are added to the database. Koh Tao Turtles

If your interested in learning more about Sea Turtles and how to identify the different species you could ask about the SSI Turtle Ecology course we offer.SSI Sea Turtle Ecology  




Whaleshark Sighting

Whale shark on Twin Peaks!! After 2 months or so of having no whaleshark sightings on Koh Tao, divers on Twin Peaks yesterday were lucky enough to spot a small 3 meter whaleshark - hopefully this means we may start to see more of them.
Darcy from ECOCEAN commented "the lack of sightings maybe a result of the abnormally high sea temperatures we are experiencing; more likely a result of less planktonic matter in the ocean due to increased temperatures and therefore lower oxygen levels in the water" so hopefully with the whalesharks beginning to come back to Koh Tao, so the temperature is decreeasing - good news for the coral too!
Remember, if you have any photos of whalesharks spotted in Koh Tao, send in your photos and we can pass them on to ECOCEAN's international monitoring database, to help us track these behemoths of the deep!


Using NASA Hubble telescope technology used to map stars, ECOOCEAN map the spots on the side of the shark, much like a human fingerprint! Recording sightings like this has already helped us to understanding behaviours of these big beauties. Learn more on their website:

A White Spectacle!

A rare white humpback whale calf has been spotted near Australia's Great Barrier Reef. Believed to be just a few weeks old, the 12ft calf was seen at Cid Harbour in the famous reef's Whitsunday Islands area by a family out in the bay in their boat. White whales are highly unusual with only 10 to 15 believed to exist among up to 15,000 living along Australia's east coast. Wayne Fewings was diving in the harbour when he spotted the animal surfacing and described the sighting as a 'once in a lifetime experience'. He said: 'We were just drifting when I noticed the smaller whale in the pod was white. I couldn't believe my eyes. 'Then the white calf approached my boat, seeming to want to check us out. I was just so amazed at seeing this animal, it made me think how truly astounding the Great Barrier Reef is.' The calf's parents may both have been dark humpbacks carrying a recessive white whale gene, but Great Barrier Reef official Mark Read said one may also have been white themselves.

That raises speculation that the calf could be the offspring of famous white humpback Migaloo. Migaloo - the name is an Aboriginal word meaning 'whitefella' - is the world's best-known all-white humpback and has built up a loyal following in Australia since first being sighted in 1991. Humpback whales are currently on their southern migration, and the baby will be feeding heavily from its mother as it lays down fat stores for the 'cold Antarctic waters'. Its sex was unknown and Mr Read said there were no plans to give the young mammal a name of its own. Australia's east coast humpback population has been brought back from the brink of extinction following the halting of whaling in the early 1960s.

A Team Effort!

Yellow saddle goatfish work together to catch their dinner, according to scientists. When an individual chases its prey around a coral formation, others gather around to block escape routes. The unusual co-ordinated behaviour was observed by scientists in the Red Sea, off the coast of Egypt. Yellow saddle goatfish (Parupeneus cyclostomus) are tropical fish found in the Indo-Pacific region, an area that is thought to be home some of the world's richest marine life. They have long whisker-like "barbels" protruding from their mouths, which they use to detect the movements of prey in coral reefs.


"The evidence is growing and growing that fish can show astonishing behaviours” Prof Redouan Bshary, University of Neuchatel, Switzerland The fish are known to live in groups that are based on their size rather than family relationships, with similarly sized fish forming groups. When a single goatfish chased its prey, the rest of the group worked together as a team to ensure its success: "Blockers" spread out across the coral formation to prevent the prey from escaping while the "chaser" pursued its target. Similar behaviour has only been identified in a handful of species - primarily mammals including chimpanzees, orcas, lions and dolphins, but also birds. Very few fish have been seen to "work together". If you fancy seeing this for yourself, Koh Tao has many goat fish species, including the Indian.

Another Day - Another Whaleshark!

Here on Koh Tao we are lucky having the chance to dive with whale sharks every other day. Only about 1% of the Earth’s population has ever seen a whale shark, let alone been diving with one! A whale shark (Rhincodon typus) is the biggest shark AND the biggest fish on the planet. It’s not a whale, even though the name might fool you! They are easily identified with their light colored dots on darker skin and a constant massive grin. Its mouth can be up to 2 meters across, has about 8,000 tiny teeth and still they only feed on plankton and the occasional small fish. Whale sharks are filter feeders and for every pound the whale shark weighs it needs 20 pounds of plankton to fill up! Even though their skin is really thick (up to 17 cm) they don’t like to be touched and here at Big Blue we go by the Divers Etiquette Whale Shark Code and always leave at least 3-4 meters between us divers and the whale shark. There is still a lot we don’t know about these beautiful creatures and it is especially hard trying to define their maximum size, age and weight! Stories have been told about 21 meter long giants but the largest verified whale shark was caught in Pakistan in 1947. That whale shark was 12.65 meters and weighed over 15 tons!

Whale sharks are known to be solitary creatures but in 2009 of the east coast of the Yucatán Peninsula, Mexico over 420 whale sharks were sighted at the same time. Sadly, whale sharks are still kept in aquariums all over the world. What scientists do know is that these animals like their space. Still, four whale sharks are being kept in one tank that is 10 meters deep, 35 meters wide and 27 meters long and holds the equivalent of 3 Olympic-sized swimming pools worth of water which makes it a big tank but no way near big enough… Luckily most of us prefer them in the wild, where they belong! If you haven’t seen one yet – well, sign up to go diving with the best dive master & instructor team on Koh Tao, next whale shark could be seen tomorrow so don’t miss out!

Turt-ally amazing!

Another day, another 4 turtles! Adult hawksbill sea turtles have been known to grow up to 1 m in length, weighing around 80kgs on average. The heaviest hawksbill ever captured was measured to be 127 kgs. The hawksbill sea turtle has several characteristics that distinguish it from other sea turtle species. Its elongated, tapered head ends in a beak-like mouth (from which its common name is derived), and its beak is more sharply pronounced and hooked than others. The hawksbill's arms have two visible claws on each flipper. Big Blue had the great pleasure to spend our night dive (!) with one juvenile hawksbill turtle last night, and then we were greated by another 2 at Hin Wong Pinnacle this morning. And as if that was not enough - there was another hawksbill turtle at our coral nursery just an hour ago! Haven't seen one yet? Then come diving with Big Blue!


Jellyfication of the sea

With its eight thin tentacles, four thicker "arms" and purplish mushroom-shaped bell, the Pelagia noctiluca or mauve stinger has become a regular, unwanted feature of the Côte d'Azur.
Despite the use of protective anti-jellyfish nets, thousands of the ancient organisms, whose population is thriving thanks to overfishing and global warming, still make it into swimming areas and are washing up onto Riviera beaches. Contact with its hairlike tentacles that can reach three metres in length causes nettle-like burns that take three days to clear and can provoke asthma and allergic attacks, and in rare cases heart failure.
To help swimmers avoid being ensnared in shoals of the poisonous invertebrates, the oceanological laboratory of Villefranche-Sur-Mer is launching a 48-hour internet jellyfish forecast.
"We're offering a five-point probability rating going from zero (no risk) to five (maximum jelly alert) on beaches of the Alpes-Maritimes region," Lars Sternmann, one of ten scientists working on the project told Le Parisien.
Biologists say their proliferation is in part down to climate change and rising water temperatures, but also a decline in its only real predators – turtles and tuna. The species, which glows in the dark (!!), has also benefited from rising plankton levels and pollution-related nutrients.
All the oceans of the planet have seen rising numbers, leading to long-term fears of a "jellification of the oceans," according to Jacqueline Goy, a medusa specialist at the oceanographic institute of Paris.
Source: Henry Samuel, The Telegraph

Whalesharks all around!!

Well haven't we come into a bit of luck! Despite monsoon season looming ever closer, the diving has never been more glorious. we are still enjoying crystal clear calm waters and sunny weather, but on top of that, how about adding 3 whalesharks spotted at Chumphon today and yesterday? Yes please! To have so many whalesharks in close proximity to our reefs means only one thing - that our reefs are producing alot of food for these massive creatures. Usually preferring the solitary life, whalesharks are known to school only when there is high productivity in an area, such as Ningaloo reef in Aus and our very own Chumphon Pinnacle! Whalesharks feed primarily on plankton, with over 8,000 bristle-like teeth filtering the waters for these tiny tasty treats. Whalesharks are thought to detect areas with high productivity (high amounts of plankton) through chemical sensing. Sharks have 2 extra senses than us - the jelly-like filled channels in their nose known as the Ampullae of Lorenzini detect electircal pulses in the water and are used to locate food, mates and danger. They also have sensitised lateral lines - two lines that run either side of the whalesharks body which help detect movement in the water. Although we know this, we still don't fully understand these huge beauties, such as where they reproduce. There is a lot of research still being conducted on whalesharks, some of which we contribute to here at Big Blue Conservation. Pretty cool huh? And you can see them in all their glory at Chumphon right now!


The Koh Tao Shark Survey

On Koh Tao, we love our sharks. Whether it's snorkelling or diving with them, or watching a documentary on these ancient fish, we're there. So we want to make sure our shark populations on Koh Tao are being well looked after, so we have started the KOH TAO SHARK SURVEY. The aim of this group is to keep a database of our shark populations on Koh Tao. If you've seen a shark on Koh Tao, please submit sightings of ANY sharks, preferably with photos, where it was seen, the date and time, the depth of the shark, any behavioural observations and distinct markings or scars, and the sex of the shark if known (males have claspers, females don't). You can send us this information through This email address is being protected from spambots. You need JavaScript enabled to view it., or join our group on Facebook ("The Koh Tao Shark survey"). Even if they were sighted a while ago, if you have photos then please submit these too! This will help us monitor our shark populations on Koh Tao and provide us with observational data for research. All whaleshark photos we will submit onto ECOCEAN's Whaleshark database too. ECOCEAN and the Shepherd Project will use this information to assist scientific research and global conservation initiatives.

The information that you submit is encapsulated in an "encounter" that ECOOCEAN tracks.  Each encounter is assigned a unique number, and you can view that encounter at any time using the link below or by going to the ECOCEAN Whale Shark Photo-identification Library ( They will keep you informed of any changes to your submitted encounter, and email you if the shark is matched to another shark within the ECOCEAN Whale Shark Photo-identification Library.  We will also let you know if/when and where your shark is resighted by other community members.

We have started to see many species of sharks return to Koh Tao, such as the Bull sharks and white tip reef sharks at green rock, so it's a great opportunity to have one place where information can be submitted and collected to help monitor the shark populations. Thanks!

Saved by a shark

A DAY after watching a film about being lost at sea, Toakai Teitoi was trapped in his own nightmare, drifting in a wooden boat for 15 weeks - before a shark helped to rescue him.

The 41-year-old Kiribati policeman and father-of-six relived his harrowing voyage in the central Pacific when he arrived in Majuro on Saturday on the Marshall Islands fishing boat which picked him up last week.He told of sleeping with the body of his brother-in-law who died during the ordeal, suffering severe dehydration and praying to be found alive.

Mr Teitoi's drama began when he joined his brother-in-law Ielu Falaile, 52, on what was supposed to be a two-hour sea journey back to Maiana in a 15-foot wooden boat.

But after stopping to fish along the way and sleeping overnight, they woke the following day to find they had drifted out of sight of Maiana and soon after ran out of fuel.

"We had food, but the problem was we had nothing to drink," he said.

As dehydration took hold, Mr Teitoi, a Catholic, said he turned to prayer as it gave him strength. But Falaile's health began failing and he died on July 4. "I left him there overnight and slept next to him like at a funeral," Mr Teitoi said. He buried his brother-in-law at sea the next morning.

Only a day after Falaile passed away a storm blew into the area and rained for several days allowing Teitoi to fill two five-gallon containers with a life-saving supply of fresh water.

"There were two choices in my mind at the time. Either someone would find me or I would follow my brother-in-law. It was out of my control." He continued to pray regularly and on the morning of September 11 caught sight of a fishing boat in the distance but the crew were unable to see him. Dejected, he did what he had done most days, curling up under a small covered area in the bow to stay out of the tropical sun.

Mr Teitoi said he woke in the afternoon to the sound of scratching and looked overboard to see a six-foot shark circling the boat and bumping the hull.

When the shark had his attention it swam off.

"He was guiding me to a fishing boat. I looked up and there was the stern of a ship and I could see crew with binoculars looking at me."

So the shark guided him to a fishing boat and safety. Sounds like a pretty JAWesome shark if you ask me!

source: Herald Sun, Australia


So normally I post positive things about conservation action and developments in marine biology, but today I have some news. Unfortunately our artificial reef on Sairee suffered a horrible fate yesterday. Thanks to recent zoning plans and numerous mooring lines all around the island, anchor damage is now rare on Koh Tao. However, yesterday a dive boat dropped an anchor within metres of our coral nursery and artificial reef, and when we asked the captain to pull it up, he instead dragged anchor along with one of our structures 20 metres, destroying corals that we helped propagate on our nursery. Two years worth of coral growth was destroyed as the anchor dragged our poor dome and the concrete mooring block it was attached to before hitting the existing reef and damaging that too. The annoying thing is the boat was also attached to a mooring line - so why the need for the anchor? The boat was seen dropping the anchor by two divers maintaining the nursery at the time, who just about managed to get out of the way as the structure was destroyed. Despite us telling the dive school twice yesterday, the anchor is still there, and the boat still using it to moor on. They are also no where near where they normally moor up either.


PLEASE PLEASE PLEASE dive schools tell your captains that if there isn't a mooring line for them, we will set them one up for free. Dropping an anchor can has immediate drastic effects to our reefs, and on a shallow sheltered site like Sairee with so many mooring lines already, there is no need. This anchor has done significant damage to both existing and artificial reefs, and it's lucky that the divers were not hurt in the process. I can't wait for the next Save Koh Tao season.

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