Another whale has washed ashore in Northern California marking the 12th death of the mammals in recent months and puzzling marine biologists as to why.

The Associated Press reported that the latest carcass to wash ashore came on Tuesday. Officials said the whale washed up along the Point Reyes National Seashore, but was so badly decomposed that its species has not yet been identified.

"[The condition] suggests it could be a killer whale attack," said Mary Jane Schramm, spokeswoman for the Gulf of the Farallones National Marine Sanctuary. "We are seeing them coming from so many different species and various causes of death.”

The San Francisco Chronicle has documented some of the most recent deaths and noted that on Saturday a juvenile gray whale washed up along the shore of the Sonoma Coast. Prior to that, a gray whale washed ashore in Half Moon Bay around the time that two whales, a humpback and a sperm, were found dead on a beach in Pacifica. Another dead gray whale was beached in Mendocino County last week. And, in April two gray whales came ashore in Santa Cruz County along with one killer whale not far from Fort Bragg.

The number of deaths for the large sea creatures is not completely unusual this time of year. However, the various species and manners of death are and that is what biologists will be trying determine as they consider all the factors and hope that the trend does not continue.

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