Red line shows the South carolina shark Mary Lee's position Wednesday afternoon, far inside St. Helena Sound. Photo by Ocearch

Red line shows great white shark Mary Lee’s position Wednesday afternoon, far inside St. Helena Sound. Photo by Ocearch

It may not be cause for alarm, and no alarms have been sounded. But those who live near South Carolina’s St. Helena Sound and are considering water activities ought to be advised that a 16-foot, 3,500-pound great white shark is hanging out far inside the waterway.

The massive predator entered the sound Tuesday night or early Wednesday, and as of Wednesday it was located just north of Hilton Head and south of the Edisto River.

Nobody has physically spotted the South Carolina shark, but it’s wearing a satellite tracking tag and scientists with the group Ocearch are following its first foray into an inland waterway since she was tagged in 2012 off Cape Cod, Massachusetts.

Great white shark Mary Lee during the tagging process in 2012; photo by Ocearch

Great white shark Mary Lee during the tagging process in 2012; photo by Ocearch

“It’s hard to tell, and we’ve asked locals to help us find out about the environment on our Facebook page, but it looks to be a pretty remote swampy area,” said Chris Fischer, founding chairman of Ocearch.

That prompted this comment from Don Anderson: “I live on Edisto Beach. She is in about 20 to 25 feet of water. It is a rich estuary full of shrimp and other bait. Water temp is about 68 degrees. Redfish and speckled trout are plentiful. We shrimp on the shallow marsh surrounding the area she is in.”

[Related: What to do if a great white attacks the boat.]

Another local stated that the shark is close to where fresh water is mixing with sea water, causing it to turn brackish. It would not be unusual for a bull shark to swim into brackish water, but it’s highly unusual for large great white sharks to do so.

great white shark

Mary Lee’s chart since the shark was tagged in September of 2012. Photo by Ocearch

Mary Lee has been tracked throughout a vast portion of the Atlantic. She has swum as far east as Bermuda and as far south as the Bahamas. She has approached the coastline before--she entered the Florida surf line last January--but this is the first time she has trekked inland.

It’s unusual because great white sharks, except when they’re pupping or visiting coastal seal rookeries during the primary feeding season, are believed to spend most of their time offshore.

Fischer said Mary Lee might be pregnant, but added that this is not the time of year for white sharks to be giving birth.

It could be simply that Mary Lee is fattening up on redfish and mullet.

Fischer said years of conservation efforts--notably the removal of coastal gill-nets--have allowed certain species of small fish to flourish. That could, in turn, be giving white sharks more reason to hang out around the coast.

In any event, one very large white shark has gone beyond the coast and almost up a river.

“She’s in there tight, just hanging around,” Fischer said. “She has shown over the years that there is a coastal component to her, as well as a pelagic component.”

Ocearch scientists will be monitoring Mary Lee’s position as best as it can, and will be posting updates on the group’s website and Facebook page.

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