Forces TV has been given unique access to the Royal Navy's Fishery Protection mission.
Our reporter, Rebecca Ricks, spent time on board HMS Severn as she policed the fishery limits of England, Wales and Northern Ireland.
The Fishery Protection Squadron has responsibility for 80,000 square miles of sea and the task is fulfilled by three River Class Patrol Vessels.
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The Squadron is the oldest frontline squadron in the Royal Navy and protects the hundreds of thousands of tons of fish landed by the UK fleet worth almost £700 million.
The Squadron also has secondary duties which include Maritime counter-terrorism, counter-drug surveillance and pollution control.
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