The blue whale carcass was first spotted on Saturday, June 16, 2018 near the Farallon Islands, before it washed ashore Monday afternoon in Point Reyes National Seashore.
© The Marine Mammal CenterThe blue whale carcass was first spotted on Saturday, June 16, 2018 near the Farallon Islands, before it washed ashore Monday afternoon in Point Reyes National Seashore.
The Marine Mammal Center confirmed the blue whale washed ashore Monday afternoon south of Limantour Beach in Point Reyes Nation Seashore. The organization will work with the California Academy of Sciences to perform a necropsy and determine a cause of death.

A whale watching group out on the water near the Farallon Islands came across an unpleasant sight Saturday. Instead of breaching humpbacks or playful dolphins, tourists on board got an up-close view of a blue whale carcass, floating on the water as it decayed.

Blue whales, the largest animal on the planet, are classified as an endangered species. About 2,800 live off the coast of California, according to the Marine Mammal Center.

According to a naturalist on board the San Francisco Whale Tours boat, the carcass was spotted a few miles southeast of the islands. Pictures show the blue whale stomach's extremely bloated as seagulls scavenge the remains.

The Marine Mammal Center and Golden Gate Cetacean Research are looking into what may have caused the animal's death, but are forced to rely on pictures for now. Two whale watch boats that returned to the area Sunday didn't see the whale.

"It could have drifted for miles, so it's a matter of re-sighting it," said Bill Keener with Golden Gate Cetacean Research.

In the past two months, four whales have washed up on Bay Area shores, from the Oakland Estuary to Marin County. The cause of death in all cases were determined to be human-related. Three were likely killed by collisions with ships and one was found severely entangled.