A Thousand Oaks RV dealer was sentenced Tuesday to four months in jail and three years of probation for dropping an anchor in a drunken prank aboard a cruise ship. Rick Ehlert, 45, also was ordered by U.S. District Judge Steven D. Merryday to pay a $7,500 fine and participate in substance abuse and mental health counseling. Ehlert, owner of Conejo Wholesale Auto & RV in Thousand Oaks, pleaded guilty last year to bringing Holland America's MS Ryndam to a stop when he dropped the 18-ton stern anchor after a night of drinking. The ship was traveling at 18 knots as it returned to Tampa, Fla., from Mexico on Nov. 27, 2010. The prank delayed the ship by three hours but did not damage it. Merryday called the incident a "bothersome crime," according to the Tampa Tribune. Ehlert told authorities that while he was drunk, he entered an area off limits to passengers, put on work gloves, released a cable attached to a hook holding the anchor, lifted a bar and turned a handle to drop the anchor, officials said. He said he owned a 50-foot boat with a similar anchor system.