Diving in the Seychelles in September

Conditions in September

If you're dreaming of diving into the turquoise waters of Seychelles, September is a fantastic time to consider. This month sits squarely within the transitional period between the southeast trade winds (May to September) and the northwest monsoon (October to April). What this means for you, the diver, is generally calmer seas than earlier in the year, especially as we move closer to October. While you might still encounter a gentle breeze, the strong winds that can churn up the ocean are typically subsiding. This makes for much more comfortable boat rides and surface intervals, allowing you to fully enjoy your liveaboard experience.

Underwater, September brings consistently warm waters, usually ranging from a delightful 27°C to 29°C (81°F to 84°F). This means you can often get away with a 3mm shorty or even just a rash guard for thermal protection, although a full 3mm wetsuit provides a bit more comfort and extra protection from any potential stinging plankton. Visibility during September is generally excellent. As the stronger winds die down, the suspended particles in the water column settle, often resulting in crystal-clear conditions. You can expect visibility to easily reach 20-30 meters, and sometimes even pushing beyond that on a good day. Currents are typically moderate during this time, making most dive sites accessible and enjoyable for a wider range of experience levels.

What you will see

September in Seychelles is truly special for its vibrant marine life, particularly in terms of pelagic encounters. As the waters warm up and currents become more predictable, the larger animals begin to cruise closer to the outer atolls and deeper pinnacles. You have a very good chance of spotting reef sharks, including the ubiquitous white-tip and black-tip reef sharks, as well as the more elusive grey reef sharks patrolling the drop-offs. Keep your eyes peeled for dogtooth tuna and barracuda schooling in considerable numbers, especially around the outer islands. This transition period is also excellent for manta ray sightings – while not a guarantee, September sees a noticeable increase in their presence around cleaning stations and feeding grounds.

Beyond the large pelagics, the Seychelles reefs are bursting with life. You'll be mesmerized by the sheer diversity of colorful reef fish, including parrotfish, angelfish, butterflyfish, and clownfish making their homes in the anemones. Hawksbill and green sea turtles are almost guaranteed sightings on nearly every dive, gracefully gliding through the coral gardens. For those with a keen eye for macro, the healthy coral structures, both hard and soft, are home to an array of critters – nudibranchs, squat lobsters, and various shrimp species await your discovery. This month offers a balanced mix, ensuring there's something exciting for every diver, whether you're staring into the blue for large pelagics or meticulously exploring the reef for smaller wonders.

Top dive sites this month

Given the generally calm conditions and improving visibility, September is an ideal time to explore a wide range of Seychelles' premier dive sites. For outstanding pelagic action and dramatic topography, you simply must visit the Outer Islands, such as the Alphonse Group or Poivre Atoll. These remote atolls are less affected by any lingering winds and offer pristine reefs, incredible visibility, and a higher likelihood of encountering manta rays, schooling jacks, and a variety of sharks. The deeper channels and walls here provide perfect hunting grounds for large pelagic species.

Closer to the Mahé group, sites like Brissare Rocks and Ennerdale Wreck offer fantastic diving. Brissare Rocks, with its granite boulders and vibrant reef, is a magnet for schooling fish and reef sharks. The Ennerdale Wreck, a large tanker that sank in 1970, is now a thriving artificial reef, home to groupers, snappers, and often patrolled by barracuda, providing a thrilling wreck dive experience. For breathtaking coral gardens and frequent turtle sightings, the sites around Praslin and La Digue, such as the famous Ave Maria Rocks, are in their prime during September, offering shallower, current-protected dives that are perfect for enjoying the rich biodiversity.

Practical tips for your trip

For diving in September, a 3mm shorty or full wetsuit is perfect – you'll want some protection from the sun and potential minor currents, but you'll certainly be comfortable in the warm water. This month is particularly well-suited for divers of all experience levels. The generally calmer seas and moderate currents make it enjoyable for beginners while the enhanced pelagic activity and pristine outer atolls offer plenty of excitement for advanced divers. Liveaboard availability tends to be good in September, sitting just before the peak season, which can sometimes mean you snag a great deal. However, booking in advance is always recommended, especially if you have specific dates or a particular liveaboard in mind.

When packing, remember your reef-safe sunscreen, a good hat, and polarized sunglasses for surface intervals. Don't forget a light waterproof jacket for evenings or any unexpected sprinkles. While Seychelles is generally a safe destination, it's always wise to have comprehensive dive and travel insurance. Be aware that most liveaboards operate in relatively remote areas, so having any personal medications and a basic first-aid kit is advisable. Embrace the laid-back rhythm of the islands, stay hydrated, and prepare for an unforgettable underwater adventure.