(Adds details from statement, background)
WASHINGTON, Oct 15 (Reuters) - U.S. and Alaskan authorities on Thursday said they will no longer seek additional damages from Exxon Mobil Corp over the 1989 Exxon Valdez disaster and the subsequent settlement, saying wildlife affected by the oil spill have sufficiently recovered.
The Department of Justice said it is closing federal and state judicial actions against the company and opting not to recover more damages under the reopener provision of the 1991 settlement following the spill.
"The Prince William Sound, Alaska, harlequin ducks and sea otters thought in 2006 to have been impacted by lingering subsurface oil have recovered to pre-spill population levels. Scientists have concluded that exposure to the subsurface oil is no longer biologically significant to these species," DOJ said.
"Accordingly, the governments have decided to withdraw their 2006 request to Exxon to fund bio-restoration of subsurface lingering oil patches," it added in a statement.
The 1989 spill of the company's Exxon Valdez tanker dumped almost 11 million gallons (42 million liters) of crude oil on Bligh Reef in the Gulf of Alaska's Prince William Sound, killing thousands of otters and other species.
Now, 26 years later, authorities said many species have recovered to their pre-spill numbers. A federal report released last year on one species, sea otters, noted the wide range of recovery among different wildlife.
Alaska Attorney General Craig Richards said that, while they were not pursuing the additional damages, authorities will consider alternatives for dealing with lingering oil sites.
A council charged with directing restoration efforts will consider what next steps are needed at any remaining oil sites and that U.S. scientists at the National Oceanic and Atmospheric Administration will continue to monitor those areas, U.S. and state officials said. (Reporting by Susan Heavey; Editing by Bill Trott and Doina Chiacu)