Robert Durell / LAT
The gash visible in the side of a mother humpback whale swimming upstream in the Sacramento River is believed to have been caused by a boat propeller. Although not thought to be life-threatening, the wound is more likely to heal with the salve of salt water, but the whale and her calf appear confused, distressed and unable to navigate toward San Francisco Bay and the Pacific Ocean beyond. The extent of the calf's injuries is not known. Authorities have tried several strategies, including broadcasting whale chatter underwater and blockades to encourage the endangered mammals to head for their natural habitat, so far without success.
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