SeaWorld Entertainment has dropped an appeal of citations it received after the drowning of a trainer who was pulled under by a killer whale, ending any chance of trainers ever again swimming with orcas during shows.

The marine park company said in a Securities and Exchange Commission filing last week that it wasn't going to pursue the appeal of a court's decision to uphold the citations.

Last April, the federal appeals court in Washington said SeaWorld's challenge to the finding was unpersuasive, and that the Occupational Safety and Health Review Commission was correct when it found that the SeaWorld park in Orlando had violated a federal workplace safety law.

SeaWorld trainer Dawn Brancheau was killed in 2010 when killer whale Tilikum grabbed her and pulled her into a pool.

Tilikum became the focus of a critical 2013 documentary film "Blackfish."

After an investigation into Brancheau's death, OSHA recommended that trainers perform with killer whales only when they have a protective barrier or sufficient distance from the marine mammals, making it impossible for trainers to swim with the whales during shows.

Trainers, though, will be able to swim with the whales during behind-the-scenes safety training exercises in order to acclimate whales to humans in case someone accidentally falls into a pool, said SeaWorld spokesman Fred Jacobs.

SeaWorld also has implemented new safety protocols and equipment for trainers, including an investment of $70 million in lifting floors in the pools that could quickly isolate whales.

SeaWorld also announced last week it was building new larger tanks for its killer whales, but company officials said the decision had nothing to do with criticism following the release of "Blackfish." Several entertainers, including country singers Trisha Yearwood and Willie Nelson and rock band Barenaked Ladies, have pulled out of planned performances at SeaWorld parks since the film's release.

The company's shares recently have been trading near their lowest point since SeaWorld listed its stock on public markets last year.