HILO, Hawai'i — The widow of legendary oceanographer Jacques Cousteau has spoken out against a 1,500-unit condominium development on the Big Island that her stepson, Jean-Michael Cousteau, is helping build as a consultant.

The 434-acre project, Sea Mountain at Punaluu, would be the biggest single development ever undertaken on the east side of the island. It will mostly consist of condominiums but will also include a hotel and a resort.

Francine Cousteau, Jacques Cousteau's second wife and president of a group called the Cousteau Society, said she opposes the venture.

"It has been brought to our attention that many are under the impression that Jean-Michel Cousteau has the support of the Cousteau Society in his endeavors," Francine Cousteau said in a statement. "We are extremely concerned about the potential environmental implications of the Sea Mountain resort."

The project has drawn vehement opposition from environmental groups that say it will harm threatened and endangered species like the hawksbill turtle. They also say it would ruin the cultural and aesthetic qualities of the area.

Jean-Michel Cousteau has vowed to make the project environmentally and culturally sensitive.

His nonprofit organization, the Ocean Futures Society, has been involved in about a dozen similar projects in places such as Fiji and the Cayman Islands.

The Ocean Futures Society has said it will hold educational programs and build a cultural center as part of the development. Cousteau said his society will take its name off the project if it is not done in an environmentally conscious manner.

Jean-Michel Cousteau, 68, split from the Cousteau Society in 1992 while his father was still alive. The younger Cousteau had been executive vice president of the organization for 20 years.

The divergence of how to carry on the Cousteau legacy continued to widen in 1996, when Jacques Cousteau successfully sued his son over the use of the family name on the eco-resort in Fiji.

The lawsuit prohibited Jean-Michel from using the family name on the resort without attaching his first name just as prominently. Jacques Cousteau died the following year, but the feud continued. More recently, the Ocean Futures Society and the Cousteau Society locked horns over who owned the Calypso, Jacques Cous-teau's exploration vessel.

Jean-Michel Cousteau was in the Amazon jungle filming for his nature TV show and could not be reached for comment on the condo project.

Jim Miller, one of Jean-Michel Cousteau's colleagues at the Ocean Futures Society, defended Cousteau's sincerity and devotion to the environment.

"Jean-Michel's positive work speaks for itself," Miller said. "I don't think any informed person would question his credentials."