Ask a Marine Biologist: Close Encounters of the Molluskan Kind

Ask a Marine Biologist: Close Encounters of the Molluskan Kind

This common Atlantic octopus was caught off the coast of Georgia on a research cruise and photographed by the Southeastern Regional Taxonomic Center (Photo: SERTC/SCDNR)

This common Atlantic octopus was caught off the coast of Georgia on a research cruise and photographed by the Southeastern Regional Taxonomic Center (Photo: SERTC/SCDNR)

New year, new features on the blog!

Welcome to Ask a Marine Biologist, a new column dedicated to satisfying your curiosity about mystery fish, weird beach finds, and other strange saltwater observations. Read on below for more information about how to submit your own question for SCDNR biologists to weigh in on.

The Encounter

In late December, friends Shevlin Howe and Derek White boated out to the shallow waters of Copahee Sound to enjoy some holiday fly fishing. Water temperatures were around 53 degrees Fahrenheit – well above the unusually low numbers we’ve seen this January, but still pretty chilly. The anglers were targeting red drum when they spotted something swimming toward their boat.

“We actually thought it was a redfish at first,” Howe said. “He was in about 10 inches of water, and he made a beeline to the boat.”

As the animal swam closer, the men realized the curious visitor was not a redfish but an octopus. Typically found offshore, the common Atlantic octopus sometimes shows up in the nets of shrimpers and SCDNR researchers, but it’s rarely seen by most anglers. Believed to be one of the most intelligent invertebrates, the octopus lives in crevices and dens and eats shellfish and crustaceans. At the boat’s edge, the octopus quickly showed off impressive camouflage abilities.

“He changed color initially from red to bright white but then just seemed to settle in without any fear,” White said. He hung around the boat for about ten minutes before disappearing. White wondered if the octopus might have “recognized the boat as a potential dinner bell” after spending time around crabbers.

The next week, Howe reached out to SCDNR staff to share his unusual sighting, asking whether other reports of octopuses in shallow, cold water have been confirmed in South Carolina.

Derek White captured pictures and a short video of the octopus. (Photo: Derek White)

Derek White captured pictures and a short video of the octopus. (Photo: Derek White)

The Verdict

“Very interesting,” said David Whitaker, a marine biologist and the assistant deputy director for SCDNR’s Marine Resources Division, when he heard about the observation.

“It is rare to see an octopus in inshore waters, particularly shallow waters,” Whitaker said. “My guess is the sun had warmed the shallow water and the octopus had been attracted to the warmer temperature.”

In a career spanning three decades, Whitaker could only think of one other instance when an octopus was found inshore.

“However, it’s not unusual for them to be near the Charleston Jetties, and crabbers occasionally catch them in high salinity nearshore areas,” he added. “We believe they move offshore with declining temperatures.”

As for White’s theory about the “dinner bell” effect, our crustacean biologists said that it wouldn’t surprise them if this octopus associated small boats with crab trap cast-offs, given their great intelligence.

“It was a one of a kind experience,” Howe said. His friend agreed.

“I have been fishing the Charleston waters for more than 20 years, and this was a first for me,” White said.

The common Atlantic octopus possesses special cells called chromatophores that allow it to rapidly change color and pattern. (Photo: Derek White)

The common Atlantic octopus possesses special cells called chromatophores that allow it to rapidly change color and pattern. (Photo: Derek White)

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Thanks Shevlin and Derek for sharing your sighting!

You can read more about the common Atlantic octopus here.

Do you have an unusual marine observation you’ve been wondering about? Email us at CoastalResourcesBlog@dnr.sc.gov, and we may choose it for the Ask a Marine Biologist column!

Winter Workshops for Coastal Naturalists

Winter Workshops for Coastal Naturalists