International game

• Suddenly, the peace was broken by the scream of a fishing reel as a four-metre-long blue marlin (Makaira mazaraburst) burst from the water.
• For the next hour the giant fish surged, leapt and tail walked, as my best friend and fishing companion mostly just held on.
• Recreational fishing for the largest species and individual fish in the sea like this is often called trophy fishing.

What’s the catch?

• Notably, in the 1950s, the average record-holding fish weighed a hefty 168kg, but this figure fell drastically to just 8kg in the 2010s.
• The fish are not shrinking, instead anglers are now targeting a broader range of smaller species.
• However, this might signal a concerning decline in the population of larger fish species.
• Comparing the last decade (2010–2018) to the 2000s, there has been a roughly 66% decrease in records for these at-risk species.

Tackling sustainability

• This approach records the length of the fish rather than weight, enabling it to be released without needing to kill it.
• Although releasing fish does not guarantee survival, that can be maximised by using the right gear and careful handling.
• From this year, the UK government has authorised a catch and release only recreational fishery for these fish.
• With continued careful management this should bring exciting angling, social and economic benefits for years to come.

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• Bryce Stewart receives funding from Defra and UK Research and Innovation.
• He is a member of the Marine Conservation Society and the Yorkshire Wildlife Trust and sits on the Marine Stewardship Council Stakeholder Advisory Council.