Ocean Park will close on Mondays from June 2 following a slump in visitors attributed to the Sars outbreak. As part of the move to a six-day week operation, the theme park's 700 permanent and contract staff are being asked to take four days' unpaid leave each month. Chief executive Randolph Guthrie said the move came amid substantial operating losses. 'Sars has had a catastrophic impact on the park's attendance and revenues in the last two months,' Mr Guthrie said. 'We have taken hard decisions to control costs and realign operations, but the length and severity of the downturn have made new measures essential.' Ocean Park has about 100 part-time staff but they will not be affected by the unpaid leave requirement. A spokeswoman said no one had been laid off but the business climate was being watched closely. Visitor numbers for this month have fallen 30 per cent on last year.