The SeaWorld chain's appeal against a ban on contact between trainers and killer whales during public performances has been rejected.
The decision means that SeaWorld trainers must continue to be separated from the orcas by a physical barrier during shows, although they are permitted to enter the water with the whales for behind-the-scenes medical and husbandry procedures.
The company had hoped to persuade a review commission that an initial decision by judge Ken S. Welsch had effectively imposed a double standard, but failed to do so.
The Orlando Sentinel details SeaWorld's remaining legal options, which include appealing to a US Court of Appeals. The company is yet to make a decision on its next course of action.
Trainers have not entered the water with whales at SeaWorld parks since the death of Dawn Brancheau on February 24, 2010. Brancheau, a 12-year veteran at SeaWorld Orlando, was killed when 30-year-old whale Tilikum pulled her into the water by her ponytail and drowned her following a show.
SeaWorld has since spent tens of millions of dollars on installing new safety features at its parks in Orlando, San Diego and California. This includes false-bottom floors in major show venues, as well as special underwater vehicles that could be used to distract whales in the event of trainers running into difficulties. However, the Occupational Safety and Health Administration has argued that these measures are not enough to ensure the safety of SeaWorld staff.