SeaWorld, Southwest Airlines ending partnership; airline under fire from animal rights groups

Southwest Airlines and SeaWorld Entertainment are ending their 25-year-old marketing partnership, as the airline has come under fire from animal rights activists over the relationship.

Officials at both companies said Thursday that the partnership wouldn't be renewed at the end of the year when the current contract expires. SeaWorld says the decision was mutual.

A Southwest spokeswoman says it was a business decision as the airline intends to focus on international service.

Earlier this year, animal rights activist held a rally and dropped off a petition at Southwest, urging the airline to end the relationship.

The activists cited the documentary, "Blackfish," which explores what may have caused the killer whale Tilikum to kill SeaWorld trainer Dawn Brancheau in 2010.

It argues that killer whales become more aggressive in captivity.