Have you ever wondered where our tagged sharks go? So do we!
Through the use of satellite tags, we are able to learn about the broad scale movement patterns of sharks. After the tag transmits its archived data to a satellite, we can then download that information to our computers and calculate the shark’s movement patterns. The information we receive from shark tagging is essential for shark conservation and sustainable management, because if we know where the shark is going and when, then we can better work with fisheries managers and fishers to protect any threatened species.
In this series we share the journeys of individual sharks as evaluated by our Research Director, Vinay Udyawer.
The graphic above shows the movement of a Male Silky Shark tagged in Niue in November 2022 as part of Shark Pacific’s ongoing work exploring management solutions to reported Shark depredation in Niuean waters. This shark, named ‘Mr. Grumpy’ was tagged on the Halagigie Far FAD by Noa from the Niuean Fisheries team. Mr. Grumpy was tagged on a trip where 9 other Silky sharks were tagged on offshore FADs in Niue. Of all the sharks tagged that trip, Mr. Grumpy travelled the furthest, swimming around the island in Niue for two months, before heading east through the Moana Mahu MPA, into Cook Islands waters. He spent 7 months in Cook Islands waters, before moving back west through American Samoan waters, back into Niue, and then kept swimming through Tongan waters, into Fiji. His tag detached just east of Koro Island in Fiji, with the depth sensor showing that he dived up to 254 m during the course of his travels.
Mr. Grumpy’s westward movements into Tonga was seen by five other Silky Sharks tagged on that trip, identifying the Tongan trench as a potentially important habitat for this species. His movements within Niue before he made his migration were in close proximity to a number of FADs deployed around the island, and understanding his residency and movement patterns at these FADs can help us understand and mitigate shark depredation on the local fisheries that rely on FADs to catch Tuna and other pelagic fish.
Why do you think we called him Mr Grumpy?
Learn more about how and why we tag sharks >
