Called the Fish Empathy Project, the campaign reflects a strategy shift by People for the Ethical Treatment of Animals as it challenges a diet component widely viewed as nutritious and uncontroversial.

"No one would ever put a hook through a dog's or cat's mouth," said Bruce Friedrich, PETA's director of vegan outreach. "Once people start to understand that fish, although they come in different packaging, are just as intelligent, they'll stop eating them."

The campaign is in its infancy and will face broad skepticism.