Satellite tags reveal surprising whale shark movements

The Homebody, the Deep Diver and the Beach Bum!

In 2015 guests on-board the adventure-cruise ship TRUE NORTH teamed-up with marine researchers from Conservation International and started to deploy fin-mounted satellite tags on whale sharks encountered during the ship’s Whale Sharks of Cenderawasih Bay itinerary. And the results have proved to be quite surprising.

Each year the revered TRUE NORTH visits biodiverse Cenderawasih which lies adjacent to the spectacular Raja Ampat islands in West Papua and, everybody on-board gets a chance to swim with the ‘resident’ population of whale sharks. These encounters are quite different to more typical whale shark encounters because the sharks have formed a unique relationship with the local fisherman and, they are easily approached.

Their docile behaviour has allowed biologists to fix fin-mounted tags – a more durable type of satellite tag and, the tags have been providing unexpected data about where the sharks travel when they are not in swimming in the bay.

Conservation International’s Mark Erdmann reports “Perhaps the most surprising finding has been just how differently each of the tagged sharks has behaved. We expected to see some generalized tracks of migration but in reality each shark has largely done its own thing!”

One of the sharks has been a bit of a homebody only leaving Cenderawasih Bay once in 25 months, whilst one of the smallest sharks to be tagged – a 3 metre individual known as “Fijubeca”, has clocked-up an impressive 9000 kilometres during a similar period. The 6 metre “Moby” has recorded the deepest dive getting down to 1856 metres in the Mariana Trench whilst similar sized “Cheggers” has spent most of his time close to the surface. “Wally” has preferred to spend his time close to shore whilst other individuals have completed impressive oceanic swims.

Importantly, the satellite data has highlighted several regions of West Papua that are frequented by migrating whale sharks and, those areas are now being considered for inclusion in Indonesia’s marine park system.

The TRUE NORTH returns to Cenderawasih Bay in October and it is hoped that more sharks will be added to the tagging program.