Artists have disappeared from the calendar after they broadcast the documentary ` ` Blackfish '' It raises questions about the safety and humaneness of the killer whales in captivity . Other acts that have canceled include : Trisha Yearwood , Willie Nelson , Cheap Trick , Heart , Barenaked Ladies , Martina McBride and 38 Special . SeaWorld says the documentary ignores the park 's conservation efforts and research .
Artists have disappeared from the calendar after they broadcast the documentary ` ` Blackfish '' It raises questions about the safety and humaneness of the killer whales in captivity . SeaWorld says the documentary ignores the park 's conservation efforts and research .