Richelieu Rock

Thailand’s best dive site?

Richelieu Rock whale sharkRichelieu Rock diving is widely regarded as Thailand’s best. Richelieu dive is the best place in Thailand to see whale sharks. Located 18 km east of Koh Surin and part of the Surin national marine park it is best dived by liveaboard boat. There are moorings in place but not enough to cope with the number of boats that visit each day (sometimes as many as 10 boats) so entry will often be a live boat entry or from your liveaboard’s tender.

Most liveaboards include at least two dives at Richelieu Rock as part of their itinerary and may add more dives there if guests wish. The most difficult decision for underwater photographers is which lens to dive Richelieu with. Of course a wide angle lens is best for whale sharks but there is so much good macro photography to do here too.

At low tide the rock is just visible above the surface and it goes down to a maximum depth of 35m. The rock is horseshoe shaped and although currents can be strong at times there is always shelter on one side of the dive site. There are also several smaller rocks out from the main rock.

An ideal dive starts deep, then divers circle the pinnacle until they reach safety stop depth at the end of the dive. Richelieu is a lime stone rock and visibility is changeable. Some days it’s excellent but on other days it can be rather green with a lot of suspended matter. Of course these plankton blooms are a whale sharks favourite food.

Although Richelieu Rock is promoted as one of the world’s best places to see whale sharks, sightings are by no means guaranteed. Up until 2000 it was a case not of “will I see a whale shark at Richelieu Rock?” but more like “how many whale sharks will I see at Richelieu Rock?”

These days whale sharks are less common however some years are better than others. The ideal time of year to see them is usually February to April but you can be lucky at any time. If you are lucky enough to see a whale shark the best tactic is not to chase it but to hang in mid water and wait for it to come around again. Whale sharks are gentle giants and a wall of divers chasing them just scares them away. Whatever you do, never touch a whale shark as you can remove the protective algae coating from their skin which leads to disease.

Even without whale sharks Richelieu is a truly awesome dive. With no other land for miles around all marine life is attracted to this point. Other large visitors are dogtooth tuna, mackeral and schools of chevron barracuda.

Richelieu is covered in soft corals, sponges, anemones and sea fans and the biodiversity of marine life is amazing. Moray eels and lionfish are everywhere. Schools of snapper carpet large areas of the wall. Glass fish fill in the gaps hiding critters like shrimp and pipefish. Harlequin ghost pipefish are often found as are yellow tigertail seahorse.

There is a resident seahorse on the south west side of the horseshoe which is well known by all divemasters. The poor fellow is probably blind from all the camera strobes flashing in his face each day. Other seahorses can be found in the small caverns at the bottom of the rock as can harlequin shrimps. Frogfish and leaffish are also to be found and mantis shrimps can be seen scurrying about in the rubble.

Octopus are a common sight although they do their best to hide from view. Couples of cuttlefish are also seen just above the sandy bottom.