North Sea oil & gas operator Ithaca Energy forecasts annual production below expectations due to problems at one of its fields. Ithaca said it expected full-year 2014 pro-forma production to be about 12,500 barrels of oil equivalent per day (boepd) after deferring about 1,400 boepd of annualised production from the Causeway Area due to an equipment failure on the host platform and operational delays."It is anticipated this will take several weeks to repair and will therefore impact total fourth quarter production," Ithaca said.The group also said production during the third quarter was reduced by planned summer maintenance shutdowns, largely due to a six-week shutdown of the Cook field.Average pro-forma production in the third quarter was about11,600 boepd, reflecting a full quarter's production from the assets acquired from Sumitomo Corporation.Ithaca added that it had continued to make progress on its Greater Stella area development, with completion of works and first oil & gas production due in mid-2015.Shares in Ithaca fell 2.25p or 2.2% to 102p at 11:42 in London.