Anderson said searchers also found Fossett's tennis shoes, his Illinois driver's license and credit cards. The shoes and driver's license had animal bite marks on them.
"This reinforces our theory that animals dragged him away," Anderson said.
Previous bone fragments discovered near the wreckage were either found to be not human or too small for DNA tests. Investigators have completed their work on the ground and do not plan to resume search efforts, Anderson said.
Fossett's widow, Peggy, said in a statement Thursday that the discovery of bones was "another step in the process of completing the investigation into the tragic accident that took Steve's life."
Fossett vanished in September 2007 after taking off from a Nevada ranch owned by hotel magnate Barron Hilton during what was supposed to be a short pleasure flight.
His disappearance spurred a huge search that covered 20,000 square miles, cost millions of dollars and included the use of infrared technology.
For a while, many of Fossett's friends held out hope he survived, given his many close scrapes with death over the years. But a judge declared him legally dead in February, and his plane wreckage was found this month after a hiker came across his pilot identification cards amid a pile of weathered $100 bills west of Mammoth Lakes in the eastern Sierra.
Authorities have said Fossett slammed into a mountainside at about 10,000 feet and probably died instantly. The cause of the crash is still under investigation.
Fossett made a fortune in the Chicago commodities market and gained worldwide fame for setting records in high-tech balloons, gliders, jets and boats. In 2002, he became the first person to circle the world solo in a balloon.