Fishing regulator the Marine Management Organisation (MMO) has been rolling out the Catch App to skippers of boats under 10 metres long as the industry aims to improve records of the number of fish being caught by the in-shore fleet. Catch App landing declarations have to be within a 10 percent margin of error but breaking this rule means fishermen could face prosecution or an unlimited fine. The move could impact more than 3,200 boats around England, Wales and Northern Ireland.
But there are only a small number of vessels under 10-metres in length that have weighing scales on board, meaning most inputted weights are only likely to be estimates.
Fisheries lawyer Andrew Oliver said a change in the law back in 2012 gave judges the power to hand out unlimited fines if fishermen were found to be in breach of their MMO-granted licences.
He warned: "A starting point for a fine for a fairly innocuous breach of your licence would start at £2,500 and rise up to £100,000 in the worst cases."
National Federation of Fishermen's Organisations (NFFO) bosses are due to raise concerns about the smartphone app at a meeting with senior members from the MMO on Thursday.
UK fishermen could be slapped with a huge fine under new rules (Image: GETTY)
UK fishermen could face prosecution or an unlimited fine if they break the new rules (Image: GETTY)
Shadow Environment Secretary Luke Pollard warned the Catch App is putting those in the catching sector at "risk of widespread criminalisation".
The Plymouth Sutton and Devonport MP told the PA news agency: "We have the risk now of widespread criminalisation of the industry."
"The risk is that if calculations are over the 10 percent error threshold, that's a licence breach and a possible criminal offence.
"This is needless, costly and burdensome bureaucracy implemented by the Government.
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Luke Pollard warned the Catch App was putting those in the catching sector at 'risk of widespread criminalisation' (Image: GETTY)
"They should immediately remove the requirement for using the