South Ari Whale Sharks: Scars, Propellers and the New Rules

Why do so many South Ari whale sharks have scars? Mostly because of boats. Researchers believe propeller strikes are the main cause of major injuries in the South Ari Marine Protected Area, where young sharks feed near the surface all year. Since February 2025 a new plan sets distances, speed limits and mandatory propeller guards. On the water, change has been slow.

Most whale shark sites are seasonal. The sharks arrive with the plankton and leave when it thins out. South Ari is different. Here the whale sharks do something unusual. They stay.

A South Ari whale shark is usually a young one

Researchers describe the South Ari Marine Protected Area, known as SAMPA, as one of few places in the world where individual whale sharks stay all year. The Maldives protected areas authority says it plainly: the most important feature of this area is that whale sharks, called fehurihi in Dhivehi, can be seen here throughout the year. The area was designated on 5 June 2009 and covers 5,610.58 hectares along the outer reef of the atoll.

And the sharks are almost all young males. Of the sharks whose sex could be determined, 95.69% were male, and researchers describe the group as almost only immature males. They see SAMPA as a developmental habitat, a place where young sharks grow up and stay loyal to one area.

We know this because the same sharks have been followed for a long time. Each whale shark carries its own pattern of white spots, as unique as a fingerprint. The Maldives Whale Shark Research Programme, with help from contributors to its Big Fish Network, has logged over 8,000 encounters with whale sharks since 2006.

Every one of these young sharks matters. The whale shark is listed as Endangered on the IUCN Red List.

Where do the scars come from?

Whale sharks feed close to the surface. In South Ari they often swim just under the water line, in the same few metres where propellers turn. When young sharks live for years in busy water, small accidents add up.

In a study of 100 individual sharks recorded between 2014 and 2019, 61 had at least one major injury. The researchers write that inside SAMPA, propeller collisions are believed to be the main cause of major injuries, meaning cuts and amputations.

And the water is busy. An economic study estimated that 72,000 to 78,000 tourists joined whale shark trips in South Ari each year, with direct spending of US$9.4 million in 2013. These figures are more than ten years old. But they show two things at once. The sharks bring real income to the atoll, and the same boats that bring that income also bring risk. The authors recommend involving local people directly in collecting data, so new rules are understood and accepted.

What the new rules ask

A new management plan for SAMPA took effect on 1 February 2025. The official study material for SAMPA guides explains the main rules.

Around a whale shark there is a contact zone of 250 metres. Only 6 boats, including the ranger boat, may be inside at once. There can be a maximum of 60 visitors in the water in total, and 15 minutes in the water if other boats are waiting.

Swimmers keep at least 3 metres from the head or body and 4 metres from the tail. Boats keep at least 15 metres from the nearest shark. The speed limit is 10 knots in SAMPA, 5 knots in the contact zone and 2 knots within 50 metres, with the engine in neutral closer than 15 metres.

There is also no underwater flash, one guide for every six guests, and snorkelling only from 6 AM to 6 PM. And propeller guards, a protective cover around the propeller, are mandatory for all boats in SAMPA.

Rules on paper, boats on the water

On paper, this speaks straight to the propeller problem. In practice, change has been slow.

The deadline for fitting propeller guards was extended to 1 February 2026. A few weeks after it passed, local reporting found that almost no boats had them. That report followed the death of a visitor, a diver caught by a boat propeller inside SAMPA.

On 26 June 2026 the Environmental Regulatory Authority published a notice in the Maldives Government Gazette. It says that under the second amendment to the SAMPA management plan, boats working in the area had to fit propeller guards before 30 June 2026. After that date, only boats with guards fitted can be registered to enter SAMPA. Boats already registered, or that applied before the deadline, get extra time to fit them. How well this is enforced on the water is something we cannot yet confirm.

Legal is not the same as gentle

A boat can follow every rule and still be part of a crowd. Six boats and sixty swimmers around one young shark is the legal limit, not a kind goal.

So for South Ari we ask a few calm questions, and any traveller can ask them too. Does the boat have a propeller guard, and is it registered for SAMPA? Does the crew slow down early and put the engine in neutral near a shark? Will the guide wait, or leave, when the contact zone is already full? Does the group stay small and let the shark choose its own path?

South Ari sharks are wild and are not fed, so here the question is less about food and more about pressure.

How to be a gentle swimmer here

Slip into the water quietly, and never jump in on top of a shark. Stay at least 3 metres from its head and body and 4 metres from its tail. Never chase, touch, ride or block its path. If it turns towards you, move slowly aside and let it pass. Do not use flash.

If you see scars, do not look away. From a respectful distance, take a clear photo of the spot pattern on the side, behind the gills. The research programme explains that when you share photos with its Big Fish Network, through the Whale Shark Network Maldives app, you help it follow an individual shark. I use a small action camera kit for exactly this kind of quiet photo, with no flash. A scarred shark with a known story is easier to protect than an unknown one.

And sometimes the kindest choice is to stay on the boat. When the zone is full, waiting, or simply enjoying the reef somewhere else, is also part of a good day at sea. It is the same slow rhythm we try to keep on every Ocean Calling retreat.

Wildlife encounters are unpredictable. Swimming with whale sharks should always follow local regulations and experienced professional guidance.

Questions people ask

Wildlife encounters are never guaranteed and never forced. Ocean Calling works only with vetted, ethical local operators, and every animal is free to approach, or not, entirely on its own terms.