The men, David Waldron, 61, of Lowestoft, and Michael Michieli, 49, from Jersey, were caught on camera trawling within the three-mile fisheries limit near Bognor Regis in April and May.
They appeared at Chichester Magistrates' Court on Friday, whe
re they admitted eight offences of trawling in the area, in which fishing is excluded to protect valuable fish stocks, including the protected black bream, which spawns and lives in the waters.
The men were caught on camera by a Sussex police helicopter on April 25 and May 10 this year, in co-operation with the Marine and Fisheries Agency and the Sussex Sea Fisheries District Committee.
On April 30, the same boats, Michieli's L'Ecume II J158 and Waldron's Catherine Annie LT 45, were intercepted and boarded by officers from the fisheries patrol boat and witnessed by another fisherman on May 3.
The men were fined £14,000, plus costs of £3,000 each.
Tim Dapling, chief fishery officer for the SSFDC, said: 'We're a small organisation and working with others makes a fundamental difference to our success.
'This was our first experience of air support with the Sussex police and it was highly successful.
'Michieli and Waldron's selfish and irresponsible actions give fishermen a poor reputation, which many, I know, don't deserve.'
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