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sea blobs

These giant purple slugs are invading California beaches (some people have mistaken them for human organs)

Keep an eye out for these fellows, if you’re heading to the San Francisco Bay area.

A GIANT PURPLE blob from the sea – a slug – is invading beaches and waterways in California, and some experts say the phenomenon may be caused by warmer temperatures near coastal waters.

These California sea hares are harmless plant eaters – but their big size and unusual abundance this year has been turning heads at the shoreline at a number of beaches in the San Francisco Bay Area.

slug Clint Reynolds / Youtube Clint Reynolds / Youtube / Youtube

At least least one visitor to Almeda beach phoned police to report he had seen a human heart lying on the sand, the Contra Costa Times reported. 

However, he was told it was likely just one of the many sea hares that have been spotted in the area.

“We are getting calls from the public asking what the heck is this big weird purple blob,” Carolyn Jones, a spokeswoman for the East Bay Regional Park District said.

It’s native to our area. It’s not endangered, but they are rarely seen other than an occasional one here or there.

Officials have no precise count, but dozens have been seen on some beaches at the same time, and two dozen were spotted last month in an inlet to Lake Merritt in Oakland.

conservsyndicate / YouTube

The first ones were spotted last autumn. But more have been seen in May and June — including ones that captured the crowd’s attention last weekend at an annual sand-castle-building contest at Crown Beach in Alameda.

The slugs can reach 15 pounds or more and 30 inches in length. They are called sea hares because their thick antennae resemble rabbit ears.

The boom in sea hares may be related to warmer temperatures near coastal waters, said Morgan Dill, a naturalist at the Crab Cove Visitor Center in Alameda.

“We can’t say for sure why we’re seeing so many, but the Bay temperatures are definitely warmer this year,” Dill said.

In Oakland, local resident Joel Peter said he was stoked last month to see about 22 sea hares moving through in a canal into Lake Merritt.

“I had never seen one before, and then all of a sudden there were 22 of them with these brilliant colors,” Peter said.

They really caught my eye.

Associated Press with reporting from Daragh Brophy.

Read: Scientists have built a lab 62 feet under the sea – but they aren’t using it to explore the ocean

Read: Man dropped his iPhone into the sea and it recorded what happened 

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