Dead adult female gray whale washes up along bay near Vallejo

VALLEJO, Calif. (KGO) -- A dead whale has been spotted off Mare Island in Vallejo.

SKY7 was overhead Wednesday evening.

Video in the media player above is from a previous update

This is at least the seventh dead whale that has washed up along a Bay Area beach this year.

Giancarlo Rulli with the Marine Mammal Center told ABC7 after the initial on-air broadcast, the gray whale was an adult female that was first spotted deceased last week.

According to the California Academy of Sciences, the 39-foot-whale was spotted underneath a pier near the Phillips 66 Refinery in Rodeo making access difficult.

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For the sixth time this year, a dead whale has washed up along a San Francisco Bay beach. But scientists have an even bigger concern.

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They suspect the gray whale was possibly hit by a vessel.

The Marine Mammal Center said due to the advanced state of decomposition and location, a necropsy will not be performed. And the whale will be left to naturally decompose.