ALAMEDA — A ship that spilled hundreds of gallons of oil into the Bay was moved from its anchorage to a San Francisco pier on Sunday, escorted by a crew of skimming vessels that sought to prevent any more residual oil from polluting the water.

At the same time, rescue and cleanup crews in contamination suits scoured the sandy beaches and rocky shoreline of Alameda and Bay Farm Island to rescue tarred birds and stop the oil from damaging the areas most sensitive to wildlife.

At least 10 oiled birds have been found dead while another 30 were sent to a recovery center near Fairfield, officials said at a news conference Sunday afternoon at Crown Memorial State Beach, one of the worst-hit areas. The officials said they expect the official toll to increase, since they have not updated those numbers since Saturday night.

Many of the birds — 21 of those found alive — are American coots, a dark-colored waterbird also known as a mudhen. Rescuers also found oiled grebes and a variety of shorebirds and said the birds include those traveling through the Bay Area, since this is the migratory season.

"This is a pretty important time for migratory birds," said Laird Herkel, an environmental scientist with the state Department of Fish and Game. "There are certainly a lot of birds around here right now."

The ship, the Panamanian-flagged Dubai Star, was bound for Richmond from Mexico with a crew of 22 people and a cargo of jet fuel. It was not the cargo, however, that spilled. On Friday, the ship was making a refueling stop at Anchorage 9, south of the Bay Bridge, when an apparent mechanical failure caused heavy fuel oil — the kind used to propel the boat — to discharge into the water, Coast Guard officials said.

A representative for the shipping company, South Harmony Shipping, offered an apology at the Sunday conference but neither he nor Coast Guard officials investigating the spill have fully explained the cause. The vessel owner is legally responsible for the cost of cleaning up the spill.

"We're making every effort possible to minimize (the) impact," said Barry McFarland of The O'Brien's Group, the firm contracted by the shipping company to clean up the mess.

He said 400 to 800 gallons had spilled. By comparison, in November 2007 the container ship Cosco Busan leaked more than 50,000 gallons of bunker fuel into the Bay.

As of Sunday, crews had deployed more than 42,000 feet of boom to contain the spill and had picked up more than 300 bags of oil that had reached East Bay beaches. The affected shoreline was mostly along the west side of Alameda, including Crown Beach and Ballena Bay. The shoreline along the San Leandro Channel between Alameda and Bay Farm Island has also been affected.

"We believe the vast majority of the oil is now on the shoreline and not in the water," McFarland said.

Crews found oil in the water near Treasure Island and Yerba Buena Island, but the oil had not reached the shoreline there, they said. The Peninsula shoreline and places further north, including Angel Island and Alcatraz, appeared to be oil-free, officials said.

The ship is now at Pier 80 in San Francisco, where it was moored about 10 a.m. Sunday after being surrounded by booms.

"That's where they'll finish off the hull cleaning," said Sam Sacco, spokesman for the multiagency team doing the cleanup.

After crews recovered dozens of birds Saturday, the shores appeared quieter Sunday, said Shelly Lewis, a spokeswoman for the East Bay Regional Park District.

When she left the Alameda shoreline in the afternoon, Lewis said at least four more birds had been picked up alive. Rescuers planned to continue working late Sunday night, using flashlights to look for birds in the dark.

Residents who find oiled wildlife are asked not to pick up the animals, but rather to call the rescue teams at 877-823-6926.