HOUSTON (Reuters) — US wildlife officials have recovered over 1,000 oil-soaked turtles from the Gulf of Mexico in recent weeks, but the threat from BP Plc's oil spill has waned since the ruptured well has been capped, experts said.

On April 20, a Deepwater Horizon rig exploded and spewed oil into the Gulf of Mexico for nearly three months. US wildlife officials have been tracking the number of oiled turtles recovered since the spill. The number of turtles began to spike in late July. From July 27 through Aug. 8, the number of oil-covered sea turtles more than doubled to about 440, the US Fish and Wildlife Service reported.

Calm seas made search and capture of the oiled turtles easier, so the numbers increased, the National Oceanic and Atmospheric Administration said. Of the 1,000 sea turtles recovered since the spill began, 487 were alive and 516 dead, the US Fish and Wildlife Service said. About 570 sea turtles have been found stranded on Gulf Coast beaches, six times the number reported in previous years, said David Mizejewski, a naturalist at the National Wildlife Federation.

The recently recovered turtles have had much less oil on them, ranging from a light sheen to moderate coating, but no heavy oiling, said Barbara Schroeder, a NOAA turtle expert. ''Most of the turtles that we have captured in the last few weeks don't require any rehabilitation,'' Schroeder said.

The Gulf is far from clean and the spill still poses a danger to sea turtles, but Schroeder said there have been encouraging signs in the floating seaweed patches, known as sargassum, where young turtles in the gulf live and feed. ''Now we are starting to see much more healthy sargassum habitat,'' she said. ''The sargassum is coming back to life.''