SeaWorld, San Diego
SeaWorld has been the target of protests against its captive marine animal showsReuters

SeaWorld has told its management to end a practice few knew existed: mobilizing employees to pose as animal rights activists to spy on its critics.

The practice was intended to "maintain the safety and security of employees, customers and animals in the face of credible threats," insisted a statement from company CEO Joel Manby read at the end of a conference call on SeaWorld's quarterly earnings.

The practice was exposed by People for the Ethical Treatment of Animals (PETA), whose officers labelled it a "corporatate espionage campaign." The strategy enlisted San Diego SeaWorld employee Paul McComb to show up at animal rights meetings and PETA protests posing as "Thomas Jones," Newsweek reported.

McComb rallied against a SeaWorld float at Manhattan's 2013 Thanksgiving Day parade and was hauled in by police at California's 2014 Rose Parade. Other animal rights activists were quickly suspicious of McComb's over-the-top, overheated rhetoric. He chillingly urged, for example: "Burn SeaWorld to the ground and drain the tanks."

After complaints from PETA, SeaWorld supposedly launched an investigation into McComb's activities. He was placed on leave during the probe, but has since returned to work, according to Manby.

SeaWorld now admits that it used multiple employees to spy on critics, reports the Orlando Sentinel.

SeaWorld has faced public outrage following the release of Blackfish, a 2013 documentary that exposed the living conditions of many orca whales in SeaWorld. SeaWorld has announced plans to end killer whale shows at its San Diego park by the end of 2016.

The company's fourth-quarter earnings report showed improving attendance and revenue, but also revealed that bad weather and a slowdown among Brazilian visitors have hurt attendance this year. Last week, SeaWorld announced a management shakeup that pushed out its chief parks operations chief zoological officers

"SeaWorld's latest report confirms not only that the company has employed more than one spy to infiltrate and agitate at PETA but also that it values its spies more highly than the executives who have had their heads chopped off in droves, as at least one of the spies is still working at the company," PETA said in an statement emailed to the Sentinel.