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Scuba Diving at Koh Sii Ao Nang
Easily accessible from Ao Nang beach, this tiny island is a firm favourite for snorkelers and swimmers. The spot for scuba divers is surrounded by two huge coral gardens in the shallow areas.
This help guide contains information about the dive sites at Koh Sii Island, with extra details about the marine life living in the warm waters of the Andaman Sea.
When is the Best Season to Dive Ao Nang?
Generally speaking, you can go snorkeling and scuba diving near Krabi and the offshore islands all year round.
Even so, you'll experience some of the best scuba diving in Thailand in the calm and flat seas from the end of November through to May.
Furthermore, you should still expect to have sea temperatures around 29° Celsius (85° Fahrenheit) even during the winter months.
More than 100 islands offer divers an exciting variety of gentle sloping reefs, shallow swim-throughs, and underwater caverns.
You'll also have an opportunity to see several hundred different species of fish around seven distinct island destinations. The archipelago is only a short boat trip from Aonang, and always popular for scuba diving courses and snorkeling adventures.
Here's the thing:
Advanced or experienced divers are more likely to appreciate the deeper spots at the Phi Phi Island dive sites. This is an ideal location to see big fish, aquatic invertebrates, and colourful coral formations.
The optimum season for scuba diving in Krabi and Ao Nang peaks between the months of December and April. The dry sunny high season offers tranquil warm water diving and underwater visibility in excess of twenty (20) metres (65 feet).
Dive shops operate for most of the year. Nonetheless, the sea conditions will deteriorate from June and often result in heavy rainfall around the Andaman Sea and Phuket dive sites towards the end of October.
Pro Tip: The south-west monsoons, and general bad weather during the rainy season, both affect the underwater clarity and often produce choppy boat crossings. Hence, novice scuba divers should find better conditions in Koh Samui dive spots or Koh Tao diving sites in the Gulf of Thailand from May to September during the Andaman low season.
Marine Animals at Ao Nang Krabi
Divers will find the clearest water and picturesque scenery in the south of the island. The resident marine life is mostly macro creatures, such as nudibranch and seahorses, but you should also see snappers and scorpion fish.
The steep wall in the north of Koh Si Island is adorned with Tubastraea (sun corals), sea sponges, and sea whips.
But, if you are eagle-eyed and patient you may also spot several species of reef sharks darting through the area.
The dive sites at Krabi and Ao Nang islands are good places to see large fish families. Scuba divers should expect to catch sightings of some stunning macro marine life as well, especially:
- Banded sea snake (Laticauda colubrina)
Blacktip reef sharks- Bamboo shark (Hemiscylliidae)
- Bluespotted ribbontail stingrays
- Chevron barracuda
- Double-ended Pipefish (Trachyrhamphus bicoarctatus)
- Fusilier fishes (Caesionidae)
- Giant moray eels
- Hawksbill sea turtles
- Lionfish
- Nudibranch (sea slugs)
- Sea anemone species (e.g. Heteractis crispa)
- Spiny lobster (Panulirus versicolor)
Pro Tip: Dive in Krabi or Aonang between March and June and you may be lucky and see leopard sharks mating during their reproductive season. Koh Sii dive site has moderate water currents and an average depth of twelve (12) metres with a maximum depth of eighteen (18) metres.