According to the PETA press release, PETA’s Pro-Shark Banner to Fly Over Cape Cod, the organization will be flying a banner over Lighthouse Beach in Chatham, Massachusetts today. Strangely, the banner, which will read "Dangerous Predator in Water–YOU! Go Veg!" suspiciously reads more like a pro-vegetarian message than it does a pro-shark one. Perhaps, PETA is trying to take a cue from Finding Nemo, and the message itself is actually intended for the sharks to encourage them to switch to a vegetarian diet, which could result in a healthier lifestyle for the sharks. That would certainly be a "pro-shark" message.

Following the "Fish are friends, not food." motto, a great white shark tries out mouthful of seaweed.
All kidding aside, the PETA press release states that the message is part of campaign "raise awareness of the plight of sea animals who are killed for food." The press release goes on to discuss the detrimental effects of overfishing on marine species, including sharks. While I certainly support efforts to raise awareness about responsible conservation efforts, I’m not sure that pro-vegetarian grandstanding, really constitutes pro-shark efforts, per se.
While the concept of, "If everybody (and every animal) was a vegetarian, no marine animal would ever be killed for food,” is not lost on me, I don’t really see this as a realistic solution to overfishing or shark conservation efforts, at all. I’m also not convinced that the shock value of over-the-top, attention-grabbing efforts (such as pointing the finger at anyone within the visibility range of a banner, and calling him/her a "dangerous predator") actually do anything to help a cause. Sometimes, it seems like certain campaigns are intentionally offensive, in order to simply draw attention. While drawing attention is typically the goal of these types of campaigns, if the general public is offended by a campaign, the underlying message of it is going to be lost. That’s just my two cents, though, and you can’t even buy a gumball with two cents any more.