Image Source: SeaWorld.

What: Shares of theme-park operator SeaWorld Entertainment, Inc. (PRKS -0.70%) fell on Brexit concerns in June and on negative momentum from the prior month. According to data from S&P Global Market Intelligence, the stock dropped 18% over the course of June.

So what: SeaWorld is still struggling to overcome the damaging PR effect of the Blackfish documentary, which showcased the deaths of animal trainers caused by keeping killer whales in captivity. In its May earnings report, the company reported a wider loss than the year before, and only a modest increase in attendance.

Management has called 2016 a transitional year, and it's promised to end its orca breeding program and move from theatrical orca shows to educational ones in response to criticism stemming from Blackfish.

The company's worst day last month came following the U.K. Brexit vote, when shares fell 9% in two days. That slide stems in part from concerns that British tourism to Florida and other international locales will be affected by the sharp drop in the pound.

Now what: SeaWorld, which also owns Busch Gardens theme parks, has seen its stock fall steadily since its 2013 IPO. The company has not yet overcome the effect of Blackfish, which was initially released that year but attracted substantial attention at the 2014 Sundance Film Festival.

With global annual attendance of over 22 million, the company is still a force in the theme-park industry, but it's unclear if it can move past the negative media attention and brand perception. The strong dollar has also presented a challenge, as many of its visitors come from Latin America. Analysts are expecting flat sales and profits this year, but poor results could pressure its dividend, which offers a 6% yield. The stock could have further to fall before a potential rebound.