The Commission has decided not to follow the scientific advice of the international council for the exploration of the sea (ICES) in their proposals for fishing quotas for 2004. The ICES is particularly concerned about the perilous state of cod stocks in the North Sea, Irish Sea and west of Scotland, and recommended that the Commission impose zero catches in these areas, even throwing cod back when caught accidentally. However, the Commission plans published on 4 December state: '[T]he proposal is to maintain the North Sea TAC [total allowable catches] for cod at its current level of 22.659 tonnes.' A 53 per cent reduction is proposed for TAC of cod west of Scotland. The Commission qualifies its decision to allow cod fishing to continue in these areas by promising to strengthen the enforcement of the TACs it has set. Such measures include a maximum number of days at sea for fishing vessels, and a requirement for these vessels to stay in port or out of the fishing area concerned once those days have been used up. The Commission stated in its proposals: 'Since the TACs proposed for these stocks are not in line with scientific advice, it is crucial that they are not overshot. The best way to achieve this is through restrictions on fishing effort.' Closing the North Sea to cod fishing would most likely lead to mass unemployment among fishing communities. Cod swims alongside other fish and is often caught in the same nets, so to effectively introduce a zero catch on cod, quotas on other species would also have to be severely reduced. Hans Lassen, chief fisheries adviser at the ICES, maintains the validity of the council's advice. He told New Scientist: 'We recommended closing the cod fishery, and we're sticking to that.'