This is a screenshot from a PETA (People for the Ethical Treatment of Animals) website called seakittens.com. They want to convince people (from the looks of it, children) that fish are actually kittens of the sea.
Presumably, people think kittens are cute, and therefore do not want to harm/eat them. Their aim is to prevent the unethical treatment of fish, and more generally, all animals.
But take a look at the banner ad… Not quite in line with the goals of their organization, don’t you think?