(Adds details, updates shares)
Aug 13 (Reuters) - SeaWorld Entertainment Inc shares lost more than a third of their value after the theme park operator slashed forecasts amid a raging controversy over its killer whale shows that's hurting attendance.
The shares fell as much as 34.5 percent after the company also reported lower-than-expected profit and revenue for the second quarter ended June 30.
Protests against ocra shows at SeaWorld's amusement parks intensified particularly after a 2013 film, "Blackfish," documented the killing of a trainer at the company's Orlando, Florida park in 2010 by the whales.
A bill has been introduced in California proposing a ban on using killer whales in entertainment shows at amusement parks.
"The Company believes attendance in the quarter was impacted by demand pressures related to recent media attention surrounding proposed legislation in the state of California," SeaWorld said in a statement on Wednesday.
Attendance at SeaWorld's parks rose 0.3 percent in the quarter, helped by a late Easter this year and favorable weather, but admission per capita decreased by 2.5 percent to $37.9 million.
The company defines admission per capita as admissions revenue divided by total attendance.
SeaWorld said it expects revenue to decline 6-7 percent this year. That translates to revenue of $1.36-1.37 billion for the full year, compared with the $1.46 billion the company made in 2013.
It had previously forecast full-year revenue of $1.49 billion-$1.52 billion, which implied a growth of 2-4 percent.
SeaWorld expects adjusted EBITDA (earnings before interest, tax, depreciation and amortization) to fall 14-16 percent in the full year, which works out to $368.8-377.6 compared with $439.1 a year ago.
It had earlier forecast adjusted EBITDA at $450-$465 million.
Analysts on average had expected full-year EBITDA of $456 million on revenue of $1.5 billion, according to Thomson Reuters I/B/E/S.
In the second quarter, sales fell 1.5 percent to $405.2 million, hurt by a 1.8 percent decline in per capita guest spending as the company increased promotions.
Net income was $37.3 million, or 43 cents per share, compared with a net loss of $15.9 million, or 18 cents per share, a year earlier.
The numbers missed analysts' average estimate for a profit of 59 cents per share on sales of $445.3 million.
The company's stock, which closed at $18.90, was the top percentage loser on the New York Stock Exchange. Up to Tuesday's close, the stock had lost about 16 percent since its debut in April last year. (Reporting by Shailaja Sharma and Sruthi Ramakrishnan in Bangalore; Editing by Maju Samuel and Feroze Jamal)