Similan Island's Dive sites - including Koh Bon, Koh Tachai and Richelieu Rock - Thailand's Pearl's in the Andaman Sea
The Similan Marine National Park is located off of Thailand's west coast in Phang-Nga province, 65km from Khao Lak or 95km from Phuket island. The name is derived from Malaysian word for number nine. The nine islands are split over a 12km stretch, although Islands one, two and three remain closed to allow the reef's to regenerate. So all diving is concentrated around islands 4-9, with the exception of Shark fin Reef and Boulder city located south east of island No.3. People refer to the islands by their number as the Thai names for the island's are more difficult to remember for us farang's.
Donald Duck Bay, Similan Island No.8
There are amazing white sandy beaches to be found and great viewpoint's like this one from atop the boulders in Donald Duck bay, island No.8 (koh Similan). Another breathtaking viewpoint can also be found from Honeymoon bay on island No. 4. Now below the waves the Similan's offer some world class diving with amazing coral formations and an abundant mix of conditions and marine creatures to suite all divers.
East of Eden
This dive site is located on the east side of island No7.(Koh Pa-yu). The reef runs north to south and is one of most colourful reef dives in the Similan's. The reef slopes from 5-40m onto a sandy bottom where you can find Kuhl's stingrays ( Dasysatis Kuhlii) and large patches of Spotted garden eels (Heteroconger hassi). The reef is a mix of hard corals Staghorn coral, maize Coral, Table Coral and is littered with huge sea fans up to 2m wide. After the hard coral stretch a sandy patch appears and in the middle there is a table coral 14m deep and is where Scarface the giant moray eel lives. You may have heard the story of a dive guide loosing his thumb while feeding a giant moray (Gymnothorax javanicus), well this is the one. Click moray attack video to see what happens that one time he had a bad day. The highlight of the dive is the coral pinnacle (Ruan Gluay-mai - Orchid Garden) towards the south 18-10m depth which is covered in soft coral and huge sea fans. Past the pinnacle continuing to the south go shallow to find the Japanese garden of turtle grass and soft coral. Keep a look out for Hawksbill turtles (Eretmochelys imbricata) and Green Turtles (Chelonia mydas) here.
Dive Tip
This site is best dived from North to South and because of the mix of depth offers both the option for a check out dive or an early morning deep dive. The shallow area's 5-15m make an ideal location also for the last dive of the day, sunset or night dive. Keep a look out for Lobsters, Decorator crabs, Sponge crabs, Shrimp hiding in the cracks.
Photo Tip
Due to the normally good visibility on this site (20-40m) I would advise a wide angle lens. You will find here schooling tunas', Trevally, Emporers, snappers added with the clear blue water can make for some great shots, with blue water background or sprawling reef. The pinnacle makes for a brilliant down/up WA shot with flash to light up all those amazing colours in the soft coral's.
East of Eden pinnacle - Orchid Garden.
Deep Six
On the north end of island No. 7 a collection boulders with soft coral's and sea fans extends out from the tip and submerges to 40m. There are a number of large boulders that have come to rest on one large boulder in the middle to form 3 swim through's 12-21m. This is the main reason I like this dive site, as the architecture provides something different from a normal sloping reef. Take your time through the swim thru's as you can find stingrays and normally large sweetlips hiding inside. Away from the boulders 26-35m heading north keep a look out for White tip reef sharks (Triaenodon obesus). Schooling Trevally (Carangidae), fusilier (Caesionidae), snapper (Lutjanidae), Sweetlips (Haemulidae). Look out for frogfish, ornate ghost pipefish, Ribbon eel's (Rhinomuraena quaesita), between the rocks and channels. The visibility can vary from 15-25m during the season and does occasionally get frequented by whale sharks and manta rays.
Dive Tip
The site also can be prone to strong currents which flow in a northeast to southwest direction during low tide and vice versa during high tide, so be careful as the current can pull you away from the boulders. A mooring is attached to a large boulder and makes for a great descent/ascent line and once below 10m the rock provides shelter from the current.
Oriental Sweetlips - Plectorhinchus vittatus.
Photo Tip
I find it to hard to get a decent picture of a White tip reef shark here as they are normally below 30m, where it is darker and not enough light and they are shy and do not stay around for long. I tend to find I do better with getting some nice shots of people going through the swim thru's or reef fish like Harlequin sweetlips which are found in groups of around 10 or more individuals. There is also frogfish, ribbon eel's and nudibranch's to be found here. A lens in the 17mm to 70mm range is a good choice for this site as you get the flex ability of being able to get reef fish as well as some great macro photography shots.
Elephant Head
Not sure where it got it's name from as I cant see it myself but is located about 1km south of island No.8 and is 3 pinnacles surrounded on the east side by a number of large boulders, which slope of to 35m. Like Deep six these boulders have formed a number of swim thru's on the east side and a channel on the south east side. Soft coral's hang in the caves and the boulders are home to numerous sea fans, look out for Oriental and Andaman sweetlips patrolling the caves and swim through's. The rocks and boulder are dotted with Blennies (Bleniidae) and Wrasse (Labridae). If you head away from the boulders to the east or north around 35-40m keep a look out for white tip reef sharks lounging around on the sandy bottom. If the conditions are suitable, i.e. the surge is not to bad, look out on the south east side for a crack about 8m deep that sometimes has some juvenile white tip reef sharks.
Dive Tip
Strong current can swirl around this open site. Especially the full/new moon phases during the month the surge here can be very strong so caution is urged when entering the swim thru's and caves or getting shallow and close to the rocks. There is no mooring line here so you must make a free descent/ascent making sure that you swim away from the rocks for your boat pickup.
White tip Reef Shark - Triaenodon obesus.
Photo Tip
I have the same problem here as Deep 6 as the White tip sharks are deep and cautious of approaching divers and keep their distance. I find that something like a 17-70mm lens would be suitable to get the schooling fish, some nice cave shots and to take advantage of any nice macro that you come across.Look to the south of the channel on the west side, away from the rocks at 26m for the chance to see a ribbon eel
Rocky Point/Christmas Corner
This site is another cluster of submerged boulders surrounded by sand with a mooring line marking middle of the large boulder stack. It is located on the northeast tip of island No.9 (Koh Ba-Ngu). This site provides both a deep area off to the north of the mooring line and a nice shallow reef area 10-12m deep running east to west along the island. After making a circuit north and to the deeper water down to 30-35m, you can easily navigate back back to the shallower reef area to finish the dive. This reef is covered with many different types of hard corals. Octopus (Octopudidae) also are a regular along this reef system as well as colourful Nudibranch's, Red Fire Dartfish (Nemateleotris magnifica), snappers, schooling Bluefin Trevally mixed with Small Toothed Emporer's hunting side by side along the coral heads. Watch out for the Emporer fish's dramatic colour change as it goes into a feeding frenzy.
Dive Tip
The current here can be strong so it is advised to jump in and descend along the mooring line. If you make a free descent it is possible the current will push you away and you will miss the reef. Once you are down to the bottom of the boulders you are able to follow the contours and remain out of the current. With the boulders and especially the channel located to the south it is possible to gain shelter and make you way to the shelter of the island and hang around the shallow reef to end the dive where is one of the best chances to encounter a number of turtles and Leopard/Zebra sharks (Stegostoma fasciatum).
Photo Tip
The visibility is usually good here (20-25m) and is the perfect opportunity to try and get that perfect turtle shot in the nice blue shallow water of the reef area.
Red Fire Dartfish - Nemateleotris magnifica.
Christmas Point
The pinnacle from this site breaks the water on the northwest side of Island No. 9, not far from Rocky Point. There is a reef system of hard coral, table, maize, brain, staghorn located in the shallow water towards the island about 10-12m. From the pinnacle a large number of boulders descending west down to 35m. On your descent keep a lookout for a small valley between two of the huge boulders at 20m and a swim thru at 24. If you head north and east a little from the pinnacle you will find some smaller rocks and sand followed by another stack of boulders from 15-30m. The cracks of the boulders have soft coral and some sea fans growing.
Dive Tip
This site at certain times of the month have strong current, so it is advisable to drop in near the mooring line north of the pinnacle. Once on the bottom you will find shelter behind the boulder but be careful as the current swirls around the rocks and you can find the current changes direction a number of times. NOTE - This site took some of the hardest damage from the Tsunami and is for the moment no longer dived in order for the reef to regenerate. When we are allowed to dive there again look out for Leopard/Zebra sharks, White tip reef sharks, Napoleon wrasse, Barracuda (Sphyraenidae) , Trevally. Around the shallow reef area keep a look out for turtles munching away on the coral. The swim thru's are home to a number of Grouper (Serranidae) and sweetlip varieties.
Photo Tip
This is a site which can have a howling current so some times it may be best to leave the beast of a housing on the boat. If conditions are good, expect 15-30m visibility and a good chance to some big fish as well as some nice fish schools. Something like a 17-70mm make a useful lens here as there is not so much macro to warrant a close up lens.
Snapper Alley
Another dive site on Island No.9 is Snapper Alley located on the south east corner. This sloping reef systems is a continuation of Breakfast Bend. The visibility here ranges from 20-30m and starts at a depth of 5-10m near the island to a sandy bottom at 25m. There is a large variety of hard coral's, maize, staghorn, brain, pore and a few patches of soft corals and sea fans. The most interesting aspect of this site is the protruding rock formation to the west which underwater has a wall scattered with soft coral and sea fans. Either side of the Pinnacle you will find a swim thru, one at about 8m and the other at 18m.
Dive Tip
The current here is normally mild usually running in a east to west direction and is a good place for novice divers. There are plenty of small marine creatures here, so go slow and look under the coral and in between the rocks for Ornate ghost pipefish, Frogfish (Antennariidae), Nudibranch's and Snappers, Trevally, Scorpion Fish (Scorpaenidae).
Ornate Ghost Pipefish - Solenostomus paradoxus.
Photo Tip
There is a reasonable chance of encounters with White Tip and Black tip reef sharks, leopard sharks, so I would suggest a wider angle lens and either powerful strobes or try using a manual white balance setting. Or if your camera allows it set it to capture in RAW mode and you can adjust the white balance, exposure compensation and colour later using photoshop.
Breakfast Bend
This sloping reef system runs along the east side of island No.9 runs north to south and drops gently from 5-30m. In the shallows are hard coral clusters, with sandy patches, 10-20m is where most of the big hard coral gardens are flourishing. Beyond 25m you will find some of the finest sand you will find on any dive here and lots of it. There are 200 different kinds of Hard corals found in these waters, Staghorn, Maize, Pore, Table, to name a few of the more common ones.
Dive Tip
Here you have about 20m visibility and is an ideal location for novice divers and students. The shallow water around 5m is great for courses also a great place for snorkeling between dives. The current is mild here and is easy to drift along the reef either north to south or vice versa depending on the current. So a nice drift dive along the slope at 15m is ideal for the 3rd dive of the day.
Photo Tip
Be ready with the camera as you never know when that turtle will turn up in the shallows at the end of the dive.But be prepared as they commonly decide to play around the boat for half an hour during your surface interval. This provides the perfect setting of great clear water, lots of natural light, great under/over opportunity's and time to compose the shot.
Shark Fin Reef
This is a long line line of granite rock and boulder stretching for about 1km southeast from island No. 3. There are three points along the rock that emerge from the water and it are a couple of mooring buoys marking possible entry points. On the northern side of the rock you will find there are more hard and soft coral and it slopes to 20-25m. The south side is mainly a wall and drops off to 30m into the sand and has a number of boulders strewn around, these boulder formations provide a number of swim thru's to explore.
Dive Tip
If you stay shallow there a a couple of points where you can switch from the north to south side or the other way. The dive site is quite exposed and can have strong currents. Fortunately though the rock provides the perfect protection so if the current is running north east as it does during the rising tide, you stay on the north side of the rock. Visibility is usually 20-30 and is not recommended for novice divers. The thing I like most about here is the sheer wall on the south side and the Bumphead parrotfish (Bulbometopon muricatum) that cruise around the reef. I tend to find them in about 14-16m and nearer the north west end towards island No. 3. When I make my entry here I do it about half way along the rock as I find more coral and regular encounters with them and the Napoleon Wrasse that live here. There are higher concentrations of Boxfish here than any other site I know in the Similan Islands.
Bumphead Parrotfish - Bulbometopon muricatums.
Photo Tip
The highlight of this dive for me is not the schooling reef fish, snapper, fusiliers etc, but also chance for a nice close encounter with a Bumphead parrotfish or Napoleon Wrasse. I would not suggest a macro lens for this dive. This site also has one of the best concentrations of puffer fish, white spotted, blue spotted, yellow boxfish. This place is also great for schooling batfish (spadefish) and it is not uncommon to have a school of 20-30 follow you during the dive for 30-40 mins, this gives you plenty of time to tweak those settings to get the perfect shot.
Boulder City
This collection of submerged boulders is located about 2km southeast of island No.3, adjacent to Shark fin reef. There are 3 major boulder formations with around 30m of sand between each one. The tops of the boulders are from 12-18m at the shallow point and drop to35-40m. There are soft and hard corals and sea fans protruding from the boulders and cracks. This is a more challenging dive due to the strong currents that sometimes flow along here and also the depth of 12-40m.
Dive Tip
It is worth taking some extra time to think about the conditions before you jump in on this one. Check the tide chart, speak with the boat captain and the dive guide. This is a nice dive if planned properly and the exact opposite when not. When you have strong current here it is possible to drift from the boulders on the south mooring to the boulders on the north one assuming you have read the tied correctly. This is ideal as an early morning deep dive, you will be spending more time over the 20-30m range as you make your way between the boulder formations and rocks, so watch the air and NDL limits. Here you will likely find Leopard and White tip reef sharks, Napoleon Wrasse and Bumphead parrotfish. There are many colourful reef fish to be found here including many types of Anglefish, Parrotfish, gobies and if you are in the right season Manta rays are often seen gliding past, so keep an eye out on that safety stop.
Photo Tip
Boulder city is normally a fast deep dive so my advice is go medium to wide angle lens, you don't get long at those depths and you wont be staying in one place. A very high chance to see bigger fish here, like Leopard, White Tip reef sharks, Manta Rays, Napoleon Wrasse. Oh and the only place I know of the in Similan's to where you find Palette surgeonfish (Acanthurus albipectoralis).
Giant Manta - Manta birostris.
Koh Bon
This small island about 20km north east from island No.9 has two dive spot choices and is lucky enough to be part of the Similan national park. Koh Bon Pinnacle is about 600m northwest of the island and starts at a depth of 18m and drops off quickly to 40m+. The top is covered in soft coral and sea fans down to 35m. Koh Bon West Ridge is the more popular dive spot and is a rocky ridge the extends from the north west corner of the island. It is easy to find as it has a whole through which you can see Koh Tachai. This ridge extends below the surface to 35m+. The ridge wall has an abundance of small soft coral and around the corner to the north you will large patches of hard coral common to the area.
Dive Tip
On the pinnacle it is advised to check the tide tables carefully as strong current can swirl around the rock. There is very rarely a buoy line so a free descent is needed and in strong current it is easy to loose the pinnacle if you descend to slowly. On the plus side it is a great place to see Nurse and Leopard sharks, large Stingrays (Dasyatidae) like the Blotched and Jenkins fantail Rays on the sandy bottom 35m+. Koh Bon West Ridge provides some shelter from any current and can be dived northeast to southwest depending on current direction. At the bottom of the ridge around 30-35m look out for Leopard and White tip reef sharks, but be careful as the water tends to flow down the ridge making it easy to go down and can be quite a jog to get back to the reef and shallow water. Koh Bon is widely known as a Manta ray(Mobulidae) station and during the right months of the year (Jan - April), they are encountered on a regular basis. So much so that some boats will do 2 or more dives on these two spots.
Photo Tip
This dive can be Manta ray heaven and requires the use of a wide angle lens so you can fit it all in the frame. The visibility can be around 10-30m and the trade off is that there can be alot of particles in the water. So sometimes you can get really close but the particles cause alot of backscatter when using strobes, I am still experimenting with the best position and power settings for this technique. I have had reasonable results using manual white balance method and not using strobes at all. When the Manta's are not here then you can still find some sharks or rays. Also keep a look out for Long nose hawkfish (Oxycirrhites typus) in sea fans along the ridge area.
Longfin Batfish - Platax teira.
Koh Tachai
This island is about 20km north of Koh Bon and is home to the one of the Similan national park station's. It boasts 2 dive sites, Tachai pinnacle/plateau and the reef on the south east part of the island. The pinnacle consists of two submerged rock formations, the southern most being larger of the two. It is flat plateau at 14-16m surrounded by larger number of boulders descending down to 30m. The northern pinnacle is 15m north and slightly deeper at 20-35m. Buoys are conveniently located on both pinnacles. On the east side of the island we have a shallow sloping reef from 5-25m, which is scattered with sandy patches and hard coral bommies.
Dive Tip
On the pinnacle it is advised to descend along one of the mooring lines as the current can make things a little on the windy side down there. Once behind the boulders 18m you will find plenty of shelter and be able to cruise around on the north or south side depending on current direction. The top of the plateau is covered with small soft and hard coral and is often referred to as the Bonsai garden, look under the coral here for a resident Stonefish (Synanceia verrucosa). The reef is swirling with all kinds of fusiliers, Trevally, Barracuda, Batfish (Ephippidae), Tuna, down deeper around 30m you will find sandy patches home to Kuhl's stingrays and Leopard sharks. This is also a place during the right months of the year that Manta's like to come. They often stay for weeks or even months and move between here and Koh Bon while mating courtships take place. If you are lucky enough Whale sharks occasionally pay a visit before. The shallow reef on the east is great for a sunset/night dive as it is a gentle slop from 5-25m. Go slow on your night dive and look for lots of small shrimp like colourful Marble shrimp (Saron sp), or the Splendid round crab (Etisus splendidus) with it's big black claws.
Photography Tip - Due to it's hi action possibilities I would never dive here without and wide angle lens and some lighting equipment. I have also had some good results from manual white balancing at depth (Note on 1st dive) on the right days this is an awesome dive. On the other hand this spot can have ripping currents and viz down to 8m. It gets dark and murky down there on an early morning dive , so go slow and go macro.
Whale shark - Rhincodon typus.
Richelieu Rock
Without a doubt the most famous dive site in Thailand and known throughout the world as a place where whale sharks regularly make an appearance. About 30km north east of Koh Tachai, Richelieu Rock is a small pinnacle only rising about 1m out of the water at low tide. Underwater the pinnacle forms a horseshoe shape from the surface to 30m on the southern and northern points. On the south is a sandy bay with a few scattered rocks, while on the out edges of the pinnacle you will find collections of rocks around 25-28m. There are lots of small holes and cracks in the rocks which are home to many kinds of small marine animals. The soft corals on this are amazing and are spread across the entire reef, purple, red, yellow, white. Sea fans popping out from rocks and cracks that house all manner of macro critter.
Dive Tip
This site never ceases to provide me with a great dive and has something for everyone. The shear number of corals and fish like big schools of Barracuda, Trevally, Snappers, Fusiliers, marbled groupers is enough to keep the average diver happy for days. But those in the know come here to see some special things that are rare or difficult to find, such as Tigertail seahorses (Hippocampus comes), Ornate ghost pipefish (Solenostomus paradoxus) , Frogfish, Harlequin shrimp, nudibranch's, Spindle Cowries (Ovulidae). What is not difficult to find is the Whale shark and makes regular appearances from Jan-April every year. Currents can be strong here and is not a novice dive site, but the pinnacle is large enough to provide shelter on either side away from the current and still providing plenty to see.
Photography Tip - As this site is some 30km back to Koh Tachai many dive boats make 3 dives here. So my suggestion is make macro on the 1st dive, shoot the seahorses that can be found deep on the south west corner around 25-27m, it can be dark and murky down there sometimes, so focusing can be a problem. It is worth bringing a focus light. Then take your time heading north along the west wall 18-24m as you will find Ornate ghost pipefish hiding around the cracks in the rocks, whip corals. Amazingly patterned Spindle cowries are found amongst the yellow fan corals located on the northwest corner. On the east side on the outer rocks near the mooring look for a yellow painted frogfish around 26m and tigertail seahorses. Another spot for Seahorse is on the south west corner at around25-27, check out the old fishing ropes as they are a favorite for the seahorses there. The list goes on, if you take you time you will find a massive variety of macro on this site. But don't be surprised if you get back on the boat to show them your amazing macro shots only to find them showing you one of a Whale shark :)