Black Rock is a natural magnet for marine life. The small, steep limestone island's underwater terrain consists of sloping reef on the north and east sides, while the south and west sides are mostly walls, dropping vertically from the surface to around 27m. From there the slope is more gradual, stepping down to 45m or more.
Though you'll find good diving all around the island, some of the best scenery is off the southwest corner, where, at 24 to 39m, an incredibly dense mosaic of small soft corals, orange cup coral and feather stars covers the large rocks. Of particular interest are colonies of small tiger-striped anemones that cling to fan coral and gorgonian skeletons; these anemones are seldom seen outside of the Mergui Archipelago. Also check out the gravel bottom at about 30m for small but brilliantly colored filament wrasse, usually seen zipping around, flexing their fins and generally showing off
|Location:||190km (103 nautical miles) north-northwest of Kawthaung|
|Depth Range:||3-40m+ (10-BOft+)|
Other reef fish are also abundant, especially black-spotted pufferfish, spotted hawkfish, scorpionfish and blueringed angelfish. Deeper areas also see frequent-visits by schooling fish like pinjalo snappers and jacks, while fusiliers are common at every depth. Sharks are a real possibility as well, with a chance of seeing leopard, grey reef, spinner and even bull. sharks; spotted eagle rays and mantas also make fairly regular appearances.
On the island's north side, white tip reef sharks regularly patrol the deeper slopes, along with schools of rainbow runners, blue-lined barracuda, and tallfin batfish. Some especially large giant morays, as well as jeweled, zebra, fimbriated and white-eyed morays, are some of the regularly seen moray species-you may even see the latter two sharing the same crevice.
Other frequently seen creatures include octopuses and cuttlefish, both of which may be seen at nearly any depth, and Saran shrimp, normally found in shallow rubble areas when they emerge from their lairs at dusk. On the vertical walls, look for golden wentletrap snails. These tiny yellow gastropods extend a strawlike proboscis to devour their favorite prey, orange cup corals. Once the coral is consumed, female snails fill the empty skeleton with clusters of sticky yellow eggs that perfectly imitate the coral's stinging tentacles.Safety stops are rarely boring at Black Rock, as some of the most fascinating critters live in the surge zone. Of particular interest are the many varieties of cowries, nudibranchs, shrimp and unusual hermit crab species. The shallow portions of the east end are especially attractive in the early morning, late afternoon and on cloudy days, when the dozens of magnificent sea anemones retract their tentacles, revealing their vivid pink and purple bases.
While Black Rock is often an easy dive, 'strong currents are not unusual. If you are diving the west end when the current is flowing west, take care not to end up past the deep westernmost rocks. Down currents can also be very strong at these times, making it difficult to get back to shallow reef areas. That said, you have no reason to be leery about diving here; just be sure to ask your dive leader about conditions before jumping in.