Six Flags Inc., the owner and operator of Six Flag Magic Mountain in Valencia, said Wednesday that it is seeking to exchange existing bonds at a discount to extend maturities and avoid defaulting.

Bondholders in the New York-based theme park operator are being asked to swap notes maturing in 2010, 2013 and 2014 for 65 cents on the dollar in exchange for $400 million of new bonds maturing in 2016. For the exchange, bondholders will get 12.25 percent versus 8.875 percent to 9.625 percent on the existing bonds.

Six Flags’ debt is a high 14.6 times its annual earnings before interest, tax, depreciation and amortization.

Six Flags stock closed up 9 percent to $2.17 on Wednesday.

Last week, Six Flags reported a narrowed loss of $150 million on a 35-percent jump to $68.2 million in revenues as more visitors to the company’s 21 theme parks helped increase sales.