JASON BIGGS has joined the anti-Sea World campaign, by doing a funny video for PETA where he pretends he's filming a COMMERCIAL for Sea World.  Of course, he can't stop saying horrible things about the place.

He says stuff like, "Hi, I'm Jason Biggs, here to tell you that Sea World is the greatest.  When I have kids, I can't wait to take them to Sea World.  And maybe they'll get lucky [and] see one of the trainers get their legs bit off."

And, "Nothing gets me in the mood more than watching a giant, over-masturbated whale swim around in a tiny bathtub."

By the end of the video, he's in an inflatable pool naked.

WARNING: Uncensored Profanity! Nudity