A graduate student at the University of California, Santa Barbara, came across the tusk while working in a canyon on the island's remote north shore earlier this month. Nearby were several rib bones and possible thigh bones, said Lotus Vermeer, the Nature Conservancy's Santa Cruz Island project director.
"We've never discovered mammoth remains in this particular location on this island before," Vermeer said.
The Nature Conservancy and a leading mammoth expert will excavate the remains next week and use radiocarbon dating to determine their age.
Santa Cruz Island is the largest of eight islands that make up California's Channel Islands. During the Pleistocene epoch, more than 10,000 years ago, the four northern islands - Santa Cruz, San Miguel, Santa Rosa and Anacapa - formed one big island that scientists call Santarosae.
