Koh Similan National Park stretches over an area of 128 square km and is called at by cruisers leaving from Phuket. Similan, about 90 km (56 miles) north-west of Phuket, is considered as one of the best dive regions in Asia and consists of 9 granite islands with unique white sandy beaches on the eastern side of the islands and mighty rocks on the western side. In the past, Similan Islands had a lot of problems with dynamite fishing and trawls. Thanks to the regulations imposed by the National Park the reefs and the marine life had a chance to regenerate. The dive sites on the east side of the islands are usually sheltered from the wind and not very deep, therefore ideal for snorkellers too. On the western sides of the islands are impressive rocks reaching to depths of 40 m (130 ft) and more. South-western currents flowing around these rocks have shaped numerous channels, arches and tunnels. The currents also provide nutrient for the abundant variety of soft corals and gorgonian fans. Further into the blue the landscape with rocks and plateaus continues providing spots where a lot of the marine inhabitants come together. During the second half of March and April, the two hottest months of the year, the profuse fish population of the Similan Islands is joined by visitors from the open sea for example whale sharks, mantas, giant barracudas, tunas and eagle rays.
What better way to start your day off with a good breakfast? And what better way to start your exploration of Similan Islands than to jump from your Pyjamas right into your scuba gear and head for Breakfast Bend. Breakfast Bend is so-called because this is generally done as the first dive of the excursion, immediately after breakfast. With a western section that is relatively shallow and a sandy bottom, punctuated with scattered rocks, it is south-east of here where a reef-flat, primarily staghorns, has its beginnings, eventually achieving garden-like proportions. Luckily the coral mounds found in this region are relatively healthy and the many sergeant majors darting around in the water will give snorkellers a fabulous time. The reef-slope, formed by small boulders and coral shelves, with many branches of tree, leafy and brain corals is your start to a section of steep barren sandy slopes and coral stretches alternating as you head north. After a while, the corals again become completely dominant with Moorish idols, raccoon butterflyfish and Indian bannerfish found in huge numbers. And if that weren’t enough, there is still another side to this site. As you continue along the reef, bearing slightly northwest, you find another change in the seascape. Yellow, white and black featherstars, clinging to the sponge covered surfaces, highlight the large boulders and Christmas-tree worms that replace the sloping reef. This is a good place to examine the rocky surfaces carefully, as there are less obvious creatures to see. Often octopuses are present, but you have to look for them, as their coloration provides camouflage.
Looking for whale sharks? Among the world’s top listed sighting spot for these creatures is Richelieu Rock. This wall dive with its main outcrop and the smaller submerged pinnacles around it is one of Thailand’s best dives. To the south of the outcrop are three pinnacles that come up to a depth of 22 m (73 ft). The coral and marine life at this point is nothing short of amazing. Large numbers of orange gorgonian fans, radiant hermetypic corals in various shades and a profuse marine life of schooling bannerfish, single-spot and giant snappers, Indian and spotfin lionfish, Moorish idols, titan triggerfish, bearded scorpionfish, stonefish, moray eels, long-spined sea urchins, shrimps, crabs and colourful nudibranches; they are all in a constant competition of providing the best opportunity for a picture.
But wait; there is much more to this area. As Richelieu Rock is the only food source in the near region, this spot is excellent for large pelagics such as rainbow runners, great barracudas, trevallies, tuna and jacks.
If you decide to explore the eastern shelves of this site, you will encounter an enormous carpet anemone that is home to a family of tiny porcelain crabs while above you, in the shallower waters, a couple of schools of pinnate and dusky batfish swim by.
If you are looking for an unbelievable underwater terrain, Elephant Head is the spot you must not miss. The dive takes you around huge boulders, some with frames measuring over 30m (100ft), sitting individually or stacked high to form daring swimthroughs comprising arches, caverns, gullies and tunnels at all depths. And the site has an abundant variety of marine life and hard and soft corals to boot. As you descent at the mooring buoy you approach the first colossal granite boulder. Parrotfish seem to favour this part of the site particularly. If you ever wonder where east and west is during your dive, the boulders will tell you as their exposed western faces have far less soft corals than the eastern faces. Further south single boulders with patches of sand between provide home to Emperor and Imperial Angelfish, titan triggerfish as well as schools of yellowtail fusiliers and juvenile yellow snappers.
Although rivalled by Elephant Head, Chicken Hair Reef is among the top dive sites in the Similan group. Aside from the lack of any wrecks, there is something here for every diver so be sure not to leave your camera at home as you would definitively regret it. Descending first from the inner buoy to a rocky plateau at 15 m (50 ft) you arrive at what looks like a huge stage where fish scuffle for limelight. Powder-blue Surgeonfish, spinyboot and masked unicornfish, pennant bannerfish, Moorish idols and juvenile titan triggerifish are all battling to provide an excellent opportunity for a picture. A sheer-walled gully tapering down towards the southwest invites to venture into, but it soon becomes to narrow so really the best way to observe it is to follow slightly above its path. Some of the residents of this gully are impressive gorgonian fans, radiant soft corals, colourful sea trout and lionfish. The following sections of the dive that unfold before the diver are nothing short of spectacular. There a series of titan, undulated and scythe triggerfish, large numbers of big bullethead and bicolour parrotfish pecking away the hard coral skeletons. Continuing further you will encounter yellow-margined moray eels, leaving their lairs to spring on their prey. Just northwest of the inner buoy lies another great area. A group of three rocks form a pyramid, broken by a narrow gorge running east-west. The area here is a true melting pot of the marine life. Jacks, humpback, single-spot, white and blue-lined snappers, red coral trout, Indian lionfish and oriental sweetlips in a setting of seafans, sponges, yellow crinoids, featherstars and soft corals. Further to the west to this melting pot you pass over the single geometrical rock and immediately turn right and continue north until you reach a scattered area of short underwater pinnacles. Head for the bottom that is composed of fragmented coral substrate and peer hard into it and you will see the tiny but magnificent blue-ribbon eel.