WATCH: Jersey to satellite track protected Bluefin tuna

Sunday 12 September 2021

Jersey has started adding electronic tags to Bluefin tuna – an endangered fish that can grow to hundreds of kilos and generates significant commercial interest – to track their movements.

Seven fish have been tagged since the collaboration between Marine Resources and the University of Exeter started last week, with scientist Dr Lucy Hawkes ensuring the process caused minimum stress to the fish.

Climate change and rising sea temperatures have seen more shoals of Atlantic Bluefin tuna sighted around Jersey and in British waters in recent years, but they remain endangered.

Pictured: More shoals of Atlantic Bluefin tuna sighted around Jersey in recent years.

Resisting calls from the commercial fishing sector to allow the valuable creature – which can be sold for thousands on the market – to be fished locally, Environment Minister Deputy John Young last year signed a decision to officially protect stocks under the Wildlife Law.

Anyone found to have killed any species protected under the law is liable for up to two years’ prison and could be fined.

But there have nonetheless been recent concerns that Bluefin tuna is still being caught, with Deputy Young telling Scrutiny last week of live investigations.

Fisheries Officer Alex Plaster explained how the project would help his team keep a closer eye on the protected species.

“The bluefin tuna is an emerging species in our waters and now, as a result of the data we will be able to collect, through the satellite tags, the daily locations, routes and behaviour of the fish,” he said.

“We do know that over the past decade shoals of Atlantic bluefin tuna have been documented in the Western English Channel, Celtic Deeps, West Coast of Ireland and the Western Isles of Scotland. Since 2016 bluefin tuna have been regularly sighted inside Jersey’s territorial waters, usually during late summer and autumn months and sometimes in shoals of hundreds of individuals.”

Video: The tags will monitor the fish's daily locations, routes and behaviour.

According to Exeter University PhD student Tom Horton the tags on five fish will collect data for a year when then “detach automatically”, while two further tags will remain on the fish for a two-year period.”

Deputy Young said the project – which is being funded through the Climate Emergency Fund – is an example of how we can use technology to further understand our waters.”

He continued: “We are grateful to the expert marine scientists who have been lending their considerable expertise to help establish a tagging programme to satellite track Bluefin tuna in Jersey waters. The data will be useful in the future to help inform marine policies and the way we manage our waters sustainably.

“This work serves to remind us that this magnificent species is currently protected under the new Wildlife Law and it is prohibited by anyone to land these fish within Jersey territorial waters.”