A research ship planning to use controversial methods to combat global warming has docked in Bermuda — but its owners insisted last night that there were no plans for it to carry out experiments near the Island.

Weatherbird II, which arrived at St. George's on Saturday morning and is expected to stay for up to ten days, belongs to Planktos, a California-based company which intends to deposit iron particles in the sea in the hope that plankton blooms will form and absorb the carbon dioxide that contributes to global warming.

The for-profit organisation's experimental methods have been criticised by some marine scientists who claim iron fertilisation has the potential to damage marine environments and human health.

Bermuda National Trust yesterday queried why the $1.5 million vessel — which was sold to Planktos a year ago by Bermuda Institute of Ocean Sciences (BIOS) — was here.

And the Sea Shepherd Conservation Society — whose ship Farley Mowat is currently berthed at Dockyard — issued a press release calling the Planktos scheme "bizarre" and describing the reason for Weatherbird II's visit here as a "mystery".

Sarah Kelly, Planktos' outreach coordinator, told The Royal Gazette that the 115ft boat had travelled here from Florida to pick up some equipment from BIOS.

"There will be no iron fertilisation studies or micronutrient replenishment near Bermuda," she said. "There is absolutely no iron being put into the waters or studies being done anywhere near Bermuda."

She added: "A few years ago we had a preliminary conversation with the Bermuda Biological Station (now BIOS) about a potential collaboration.

"We have never had any plans nor do we have current plans to conduct any research near or around Bermuda. The Weatherbird crew of eleven are only in Bermuda to finish outfitting our ship."

Dorcas Roberts, environmental conservation officer at Bermuda National Trust, said the prospect of mass iron fertilisation in the world's oceans had caused international controversy.

"There is not enough scientific research at this time to justify such practices," she said. "We do not know why Weatherbird II is here but we would be concerned if they were considering a trial off Bermuda."

Sea Shepherd claimed it had forced Planktos to back down over plans to dump iron ore dust near the Galápagos Islands in the Pacific Ocean earlier this year.

Farley Mowat captain Paul Watson said Weatherbird II had no iron ore onboard as it had been unable to load any in the States. "They have not done their science and they are experimenting at the possible expense of the marine ecosystem," he said.

The Ministry of Environment did not respond to a query about the purpose of the ship's visit.

A duty officer at Bermuda Maritime Operations Centre said it was believed to be here for rest and recuperation on its way to the Canary Islands.

BIOS spokeswoman Tiffany Wardman confirmed that the station sold the ship to Planktos but said it was not involved in any of the company's projects.