Volunteer Julie Walters has combed Mussel Rock Beach south of San Francisco for wreckage, but all that's turned up so far are wave-battered boat parts and lumber of unknown origin.
If she did find an object with a direct link, "I would find it quite intriguing that it made this incredible journey across the Pacific," said Walters, a volunteer with the Pacifica Beach Coalition. "It would also sadden me to think of the human tragedy."
AP writers Becky Bohrer in Honolulu and Tim Fought in Portland, Ore., contributed to this report.
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