Greg Allen, 43, of Seacoast Road, Bellarena, County Londonderry, was convicted along with another man for breaching waste and marine laws.
He plans to appeal the sentence, but not the conviction.
Mr Allen said he has lost at least six acres to the sea over three decades.
He estimates that the land washed away could be worth up to £50,000 and said he was trying to prevent further erosion.
The bales of tyres were put in place to protect a motocross track developed on his ground at the edge of Lough Foyle.
Mr Allen said at least 15 neighbouring farmers are suffering the same problem as him with coastal erosion.
And he questioned why farm land further along the coast was being protected with proper sea defences built and maintained out of the public purse.
"The more ground you lose, the more our income drops," he said.
"If a farmer loses ground for a roadway, he's compensated. We're not, and we're not being allowed to do anything about it either."
Mr Allen said he has been told that to put in a properly licensed sea defence along 100 metres of shoreline would cost up to £90,000 - if it were to be approved.
He must now remove the tyres, which he said will cost him more than £15,000.
Baled tyres have been trialled as potential sea defence material by the authorities in England.
It has not become a mainstream practice.
A farmer given a suspended four-month prison sentence last week for having 20,000 tyres along the shore fronting his farm, has said he was trying to protect his land from coastal erosion.