Shares of Orlando, Fla.-based SeaWorld Entertainment (NYSE:SEAS) were off nearly 5% in early Wednesday trading, following an earnings report last night in which SeaWorld reported a Q2 loss and a decline in attendance at its theme parks.

Despite reporting record revenue for the first half of 2013, and reaffirming guidance for the rest of the year ($430 million to $440 million in pro forma EBITDA earnings on more than $1.45 billion in revenue), SeaWorld disappointed investors when it reported that its first-half loss this year  amounted to $0.66 per diluted share, nearly 10 times last year's $0.07-cent-per-share H1 loss.

Also making investors nervous, the company announced that H1 attendance at its theme parks declined 6% in comparison to H1 2012. SeaWorld attributed "the most significant portion of the decline" to an increase in the price of admission charged this year. The 10% increase in ticket prices depressed attendance, but boosted revenue, with the net effect that revenues in H1 increased 2% in comparison to last year.

The company went public in April at $27 per share and as of this writing is trading at $35.35. The company also declared a cash dividend of $0.20 per share.

-- Material from The Associated Press was used in this report.