SYDNEY — A militant animal rights group locked in a bitter high seas battle with Japanese whalers have the support and funding of a Hollywood A-list including Sean Penn and French screen siren Brigitte Bardot.

One of the world's best known and more extreme marine activist outfits, the not-for-profit Sea Shepherd Conservation Society prides itself on "innovative direct-action tactics" to confront so-called "illegal" activity on the high seas. Related article: Probe into whaling protest collision

It was established in 1977 in Canada by environmentalist Paul Watson who claims in his biography to have co-founded Greenpeace but said he parted ways with the the group over arguments about protest tactics.

In its 30-year history the group has used acoustic weapons, water cannons and stink bombs against whalers, trailed seal hunters and fought campaigns for sharks and dolphins, as well as regularly patrolling the Galapagos Islands.

Longtime patron Bardot sits on its board of advisers, along with Penn and fellow US actors Martin Sheen and Pierce Brosnan.

Sheen, Darryl Hannah and US soap star Richard Dean Anderson have all accompanied Sea Shepherd on protest actions.

Its diverse and high-profile benefactors include rock legend Mick Jagger, Red Hot Chili Peppers frontman Anthony Kiedis, surfing champion Kelly Slater, and actors Christian Bale and Edward Norton.

Former US television game show host Bob Barker donated five million US dollars to help Sea Shepherd buy and fit out a former harpoon ship for its 2010 pursuit of Japanese whalers in the Southern Ocean.

Hollywood businessman Ady Gil bankrolled a second vessel for the 2010 season -- a two-million dollar trimaran superboat originally known as Earthrace which claimed the world record for circumnavigating the globe.

The New Zealand-flagged Ady Gil was badly damaged and part of it sunk after colliding with a Japanese whaling boat Wednesday.