He estimated Dreamworld's visitor numbers will decline about 20 per cent in the 2017 financial year and then gradually improve.
Mr O'Shea also estimated earnings for Ardent's theme parks business - which includes WhiteWater World, also on the Gold Coast - would more than halve from $34.7 million to $15 million in 2016/17
Ardent's shares shed 7.25 cents, or 3.55 per cent, to $1.9675 in morning trade on the ASX on Monday and remained three cents lower at noon, continuing a decline from a share price of around $2.67 before the tragic accident on October 25.
Ardent Leisure announced on Sunday that it it has hired experienced natural disaster recovery expert Mike Mckay, a retired police inspector, to help rebuild public trust in Dreamworld following criticisms of the way the company has handled the fallout from the tragedy.
Kate Goodchild, her brother Luke Dorsett, his partner Roozi Araghi and Cindy Low all died when their raft flipped at the end of the Thunder River Rapids ride.
Ms Goodchild's 12-year-old daughter Ebony and Ms Low's 10-year-old son were also on the raft, but survived.
Dreamworld remains a crime scene and the park will remain closed until at least after the funerals of the four victims.
AAP pt
-AAP