Police say 13 demonstrators have been fined for protesting against the controversial Montauk dune project.
The demonstrators pleaded guilty to disorderly conduct charges and will pay $250 fines.
The demonstrators have been standing in the way of Army Corp of Engineers machinery, who are digging trenches for 14,000 sandbags along Montauk's beach.
The demonstrators worry the sandbags will destroy Montauk's natural, white sand beaches.
However, the project supporters say the sandbags will protect Montauk's downtown from flooding in storms.