This is quite unfortunate, I quite liked Sea Shepard's campaign against the japanese whaling fleet. But the "draw a conclusion and then shape the cited statistics to fit that conclusion" is unacceptable for any cause, be it controversy over nuclear power, use of fossil fuel, or animals/plants in the supermarket.
I would say that this needs a concerted, major effort to hit sea shepard where it hurts - their pocketbook. Putting up a website refuting Wintner's claims and suggesting that folks stop any donations to Sea Shepard would be a start. Getting the guys on "Tanked" to address this issue would also be very helpful - anyone happen to know these gentlemen and how to get in touch with them?