MOUNT PLEASANT, S.C.  Boat owners are abandoning ship.

They often sandpaper over the names and file off the registry numbers, doing their best to render the boats, and themselves, untraceable. Then they casually ditch the vessels in the middle of busy harbors, beach them at low tide on the banks of creeks or occasionally scuttle them outright.

The bad economy is creating a flotilla of forsaken boats. While there is no national census of abandoned boats, officials in coastal states are worried the problem will only grow worse as unemployment and financial stress continue to rise. Several states are even drafting laws against derelicts and say they are aggressively starting to pursue delinquent owners.

“Our waters have become dumping grounds,” said Maj. Paul R. Ouellette of the Florida Fish and Wildlife Conservation Commission. “It’s got to the point where something has to be done.”

Derelict boats are environmental and navigational hazards, leaking toxins and posing obstacles for other craft, especially at night. Thieves plunder them for scrap metal. In a storm, these runabouts and sailboats, cruisers and houseboats can break free or break up, causing havoc.