Scientists say they've unearthed fossil remains of a sea cow that lived in the shallow waters off Southern California's Channel Islands some 25 million years ago.
The fossil skull and rib cage were discovered this summer on Santa Rosa Island, in the Pacific Ocean about 50 miles northwest of Los Angeles, the National Park Service announced Tuesday.
Scientists say the remains may be from a previously unknown sea cow species but they won't know for sure until the skull is analyzed by an expert.
Some fossilized remnants of at least from four other sea cows also were found nearby.
Sea cows are torpedo-shaped plant-eaters that graze in shallow waters and can grow up to 13 feet long. The only living species are the dugong and three types of manatee.
Two researchers from the U.S. Geological Survey found the skull and rib cage in a steep ravine while mapping earthquake faults, said Yvonne Menard of the park service. Erosion may have only recently revealed them.
"This sea cow may have only been exposed the past few years after being buried for millions of years,'' said Jonathan Hoffman with the Santa Barbara Museum of Natural History, which is protecting the fossils.
"They're embedded in rock and the top surface has been exposed,'' Menard said.
That surface has been covered with plaster-impregnated bandages and burlap to protect the fossils until work to excavate them can resume in late spring, Menard said.
The work is slow because researchers need to obtain permits to excavate.
Researchers hope to uncover the teeth of the sea cow, which could help determine the animal's diet and its age when it died.