Where the Whale Sharks are

 This year, a whale shark was sighted off the coast of Ceuta in the Mediterranean Sea. Whale sharks generally have a circum-global distribution across the tropics of Cancer and Capricorn, so this sighting was an unusual one!  Clara Perez from Alnitak and Maldives Whale Shark Research, tells us more.

The Whale Shark is an enigmatic species and here at the Maldives Whale Shark Research Programme (MWSRP), we focus our research on the whale sharks sighted in the Maldives and Indian Ocean. 

The MWSRP is a research-based conservation charity dedicated to studying the whale shark and fostering community-focused conservation initiatives in the Maldives. Our goal is simple: we seek to advance the field of whale shark knowledge and to advocate for sound conservation policy in the Maldives. By encouraging and valuing community and industry stakeholder participation, we can leverage scientific research to safeguard the rich biodiversity and fragile marine ecosystems that are the basis for not only whale sharks but also life, livelihood, and culture in the Maldives. 

Whale sharks (scientific name Rhincodon typus) have been around for 60 million years, and this spotty animal is an old-timer with research estimating they can live to 130 years old. The species is considered highly mobile and can travel vast distances. For instance, a whale shark was tagged in Panama and recorded, via satellite tracking technology, travelling over 20,000 km to the western Indo-Pacific (Mariana Trench). 

Whale sharks are endangered and listed under the IUCN Red List – one of the world’s most comprehensive tools to evaluate the risk of global species extinction. First scientifically recorded in 1828, the whale shark is a fish, not a whale. In fact, they are the largest fish in our oceans. There are three species of filter-feeding sharks, and the whale shark is one of them. Filter feeders feed on tiny creatures, which form the foundation of the ocean food chain. Plankton can consist of fish eggs, copepods, krill and tiny fish. Although they are filter feeders, they have 300 rows of tiny two-millimetre-long teeth inside their huge mouths. While they do not use these for their feeding activities, it is thought that they may have use during courtship and mating. 

Little is known about whale shark reproduction; we know that they are ovoviviparous, meaning that the females produce young, which hatch from eggs inside of them, and the offspring is born free-swimming. Almost all whale shark reproduction knowledge comes from a single specimen fished in Taiwan in 1995 that was carrying 304 offspring, all at different stages of development, which (scientists believe) indicates that females store sperm.

The Maldives is home to a globally unique aggregation of juvenile whale sharks. Unlike anywhere else in the world, these sharks are present all year round and they use the shallow waters to recover and thermoregulate after their deep dives.  Declared by the Maldivian government in June 2009, the South Ari Atoll Marine Protected Area (SAMPA) became the largest protected area in the Maldives, encompassing 42 km² of coral reef habitat. The area was selected for protection because of its importance as a globally significant aggregation site for the whale shark.

Incentive-driven conservation has allowed many people to switch livelihoods from shark hunting to tourism, not only in the Maldives but also other areas in the world and offering tourists excursions to swim with whale sharks. Over-tourism, however, has become a prominent threat to whale sharks in the South Ari Marine Protected Area. Tourism activities are poorly regulated, causing unprecedented pressure on the whale sharks, with over 60% of sharks being subjected to major, life-threatening injuries from propellers and boat collisions. Further stress to the animal comes from disruptive behaviour from snorkelers, divers and boaters, causing critical ‘rest’ periods for the shark to be prematurely ended.

But tourism needs to be regulated for this whale shark population to continue for future generations and help sustain livelihoods within the Maldives. Anecdotally, tourists have expressed on social media that they will avoid tourism within the Maldives and discourage others from going due to the poor user experience in this specific area. This has the potential to affect the Maldivian economy significantly. The MWSRP works with tourism operators to improve practices by providing training sessions for guides. 

In 2013, the MWSRP launched the Big Fish Network. A citizen science platform where our network of over 180 contributors – mainly comprising local guesthouses, resort guides and dive guides – upload their encounters with whale sharks in the Maldives. We have identified over 700 whale shark individuals with their help. Fernando is the most encountered whale shark of the database, this shark has been seen every year since 2008 and has over 370 logged encounters.

This invaluable contribution of data to the citizen science platform has also led to the observation of inter-atoll movements made by some individuals, further highlighting the need for monitoring areas and assessing if they could also be given protection. There is also a global database and photo-identification library of various shark encounters and individually catalogued sharks.

Should you encounter a whale shark whilst sailing or practising in-water activities in any region, there’s a few things to bear in mind.

Code of Conduct: Key Rules

DO NOT TOUCH: Whale sharks are not tactile animals and will leave the encounter early if you touch them, disrupting their natural behaviours.

KEEP YOUR DISTANCE: Keep three metres from the body and four metres from the tail. Whale sharks can move quickly when they choose to; keep distance to protect yourselves and the shark.

DO NOT OBSTRUCT: Obstructing the path of a whale shark will cause them distress and they may leave. If the whale shark should approach you on its own accord, move out of the way quickly.

DO NOT SWIM ON TOP OF THE WHALE SHARK: Allow space for the shark to rise to the surface to continue its thermoregulation process. If you need to cross to the other side of a shark that is cruising at the surface, swim around and behind the shark’s tail, keeping your distance. If the shark cruises at a depth of fivr metres or more, you may safely swim above the shark to cross to the other side.

NO FLASH PHOTOGRAPHY: Whale sharks do not respond well to bright and unexpected light flashes.

REDUCE NOISE: Do not jump from a standing position; instead, opt for a seated position when exiting the vessel into the water. Do not shout, try to keep your fins under the water and avoid excessive splashing. Whale sharks may be receptive to long-wavelength and low-frequency sound; therefore, it is best to remain as quiet as possible during encounters.