RANCHO PALOS VERDES, Calif. (AP) — Rescuers say they'll resume efforts Saturday to free a blue whale tangled in a line off the Southern California coast — but first, they'll have to find it.

The 75-foot-long mammal was spotted Friday in the Catalina Channel, dragging several hundred feet of line attached to a buoy that may have come from a crab trap. The animal appeared otherwise healthy.

As night approached, rescuers attached a larger buoy to keep track of the mammal and planned to cut it free on Saturday.

But by morning the whale had vanished.

Peter Wallerstein of Marine Animal Rescue tells City News Service that the whale may have moved south to Orange County.

With many people out boating for the Labor Day weekend, rescuers are hoping to get word of the whale's whereabouts.

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