Overview: Snorkelling with Whale Sharks
Despite their massive size—reaching over 20 meters in length—whale sharks are very docile, gentle giants, feeding exclusively on a diet of plankton. They are usually a solitary species, but aggregate in various locations around the world. Snorkelling alongside these magnificent creatures, as they glide effortlessly through the water, appearing almost out of nowhere, is a truly once-in-a-lifetime experience.
The whale sharks typically begin arriving in the warm waters off the coast of Mafia Island from September, with numbers typically reaching a peak from mid-December through to late January. October-November usually offers clearer water, but fewer whale sharks. As the season goes into January - February the quantity of plankton increases, and in turn this attracts more whale sharks to the area, but due to plankton the water visibility tends to be less clear.
The exact excursion itinerary will differ slightly depending on which operator is booked, but will largely follow a similar set-up. Our preferred provider will collect you early morning from your accommodation and transfer you to their base on the west coast of the island. Here you will be provided with a cooked breakfast and listen to an in-depth briefing. The resident marine biologists will cover everything from whale shark behaviour, local conservation efforts and how to snorkel safely and ethically alongside the whale sharks. You will then be fitted with snorkel equipment and head out to their traditional wooden sailing dhow.
On board, towels, drinks and fresh fruit snacks are provided but we recommend bringing a sufficient supply of suncream and a hat. A 'rash vest' or t-shirt you don't mind swimming in, is also useful.
All abilities can join, but guests should note that there can be a lot of clambering in and out of the boat and so a decent level of fitness will yield a more enjoyable experience. Depending on the day and the time of year, water conditions can vary, and the whale sharks can move quickly, so we generally feel that the activity is better suited to stronger swimmers. That being said, lifejackets are provided and can be used during the snorkelling, and you will be accompanied by an experienced guide throughout.
To ensure that these excursions remain ethical and sustainable, boats and swimmers should always observe a set of guidelines; importantly all boats must adhere to a 50m 'contact zone' radius around the whale sharks, with only one boat operating within this zone. Within this, swimmers should not exceed more than 10 people in the water with one animal at any one time, not attempt to touch or ride the whale shark and avoid flash photography and the use of underwater motorised devices.
Scuba diving with the whale sharks off Mafia is not allowed and these trips are strictly snorkelling only.
Please note: Expert Africa can only arrange this excursion as part of a full, Expert Africa itinerary. See the Holiday ideas, below, for examples of such itineraries.
- Meals included
- Breakfast and snacks
- Duration
- Half day
Ideas for holidays which can include Snorkelling with Whale Sharks
These are trips which can be easily altered to include this excursion, snorkelling with Whale Sharks. It may be possible on other trips also - just ask us.

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