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 movements. 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, Dr. Vinay Udyawer.
The animation 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 FAD by Launoa Gataua, the Director of Niue Fisheries, who we’re partnered with on this project. Mr. Grumpy was one of 9 silky sharks tagged near offshore FADs that trip. Of all the sharks tagged that trip, Mr. Grumpy travelled the farthest, swimming over 4000 km (2400 mi). He swam around the Niue Island for 2 months before heading east through the Moana Mahu MPA and into Cook Islands waters. He spent 7 months in Cook Islands waters before moving back west through American Samoan waters. He then went back into Niue, but kept swimming through Tongan waters and into Fiji. His tag detached just east of Koro Island in Fiji. The depth sensor showed that he dived up to 254 m (833 ft) during the course of his travels.
Mr. Grumpy’s westward movements into Tonga were similar to 5 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 – 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 Launoa named him Mr Grumpy?
Learn more about how and why we tag sharks >
