CHICAGO (MarketWatch) -- Oil has begun leaking from the Costa Concordia, a cruise ship that foundered off the Italian coast last month, killing at least 17 and leaving another dozen or so missing, the Associated Press reports. Choppy seas are battering the carcass of the doomed vessel, owned by Carnival Cruises, raising new fears of ecological damage to the surrounding area. The oil, which is spreading from the stern, is so far just a fraction of the 500,000 gallons aboard, the wire service noted. Shares of Carnival CCL, -1.56% were up about 2% in morning action.