SEATTLE - Environmental activists who fanned out in small boats across a Seattle bay over the weekend in a protest over Royal Dutch Shell ‘s plans for Arctic oil exploration in the have damaged “precious habitat” on the sea floor, a state official said on Friday. Cables used to moor a 4,000 square foot (370 sq meter) floating barge dubbed “The People’s Platform” to the floor of Elliott Bay became wrapped around an old steel piling and pulled it over, disturbing aquatic habitat, Department of Natural Resources spokesman Joe Smillie said. “It’s a pretty precious habitat down there,” Smillie said. “Anytime you disturb it and move it there are implications to the food web.” The area is a popular underwater “dive park” for people who venture below the waves to see octopuses, sea stars and anemones, among other aquatic life. Environmental groups have vowed to disrupt the Anglo-Dutch oil company’s efforts to use Seattle’s port as a home base for two of its drilling rigs destined for the Chukchi Sea off Alaska, saying drilling in the remote Arctic waters could lead to an ecological catastrophe. The solar-powered barge was used as a platform for speeches and a musical “jam session” over the weekend, said John Sellers, founder of the activist group Mosquito Fleet. Sellers said he apologized for the damage, which was limited, and said crews have anchored the barge in a new area deemed by divers to be a less sensitive “underwater desert,” and materials used to moor the barge were left on the sea floor. Activists will not face a fine, though they will have to pay for any cleanup costs, which have not yet been calculated, Smillie said, adding that activists have submitted an application for an extended-use permit for the barge from the state. “Of course the last thing we wanted to do was to do any harm to the sea life,” said Bill Moyer, executive director of the Backbone Campaign. “If we could do damage by putting down an anchor, imagine how much damage an oil rig could do in the Arctic.”