Shark facts

The great white shark:The largest predatory fish on earth.One drop of blood in 25 gallons of water can be smelled by a great white from as far as three miles.15 feet, average adult length; specimens have been bigger than 20 feet and 5,000 pounds.Swim up to 15 mph.33 percent to 50 percent of 100-plus shark attacks each year are great whites. Most aren’t fatal. Sharks are naturally curious and will sample bite.Unknown, the number of great whites in the world. The sharks are considered endangered and in precipitous decline because of overfishing.National Geographic

Now don’t freak. It’s very likely that a 16-foot-long, 3,456-pound great white shark didn’t actually swim up to Daniel Island on Sunday.

But “I have no doubts it was close to shore,” said wildlife biologist Bryan Frazier, with S.C. Natural Resources Department. “It might have stuck its head in the harbor.”

The satellite tag ping from “Mary Lee” on Monday night put her back in the ocean off the Savannah River.

The ping that placed Mary Lee on top of Daniel Island was almost certainly an errant one, said Chris Berger, of Ocearch, the sportsman research group tracking the great white. Because the satellite can read the shark only while it shows its dorsal fin at the surface, and the satellite is orbiting, not all readings are considered accurate.

But the huge “lion of the ocean” evidently was close enough to Isle of Palms over the weekend that surfers who were warned didn’t put in.

“She was right at the surf zone edge (based on the pings). We all stayed out of the water,” said Roberta Patrick of Sullivan’s Island.

The large, great white female was tagged in September off Cape Cod by Ocearch, a group trying to learn more about the little-known habitats of the apex predator of the seas, so people can be safer.

No sooner than Mary Lee was tagged, she made her way south, pausing for a short time off the Chesapeake Bay and apparently hunting at the Charleston Bump before making a beeline to the harbor’s mouth.

In autumn each year, sharks gather along the Charleston jetties to feed on large red drum making their way offshore. A 13-foot great white found on Morris Island in November 2008 had drum scales in its stomach.

Scary as it sounds, great white aren’t strangers to the Lowcountry, although they are rare.

They don’t seem to stay put here. They appear to migrate along with other species to winter in Florida waters where they more commonly are found, said Mel Bell, DNR fisheries office director.

In fact, like right whales that are an occasional prey, Mary Lee might have been headed to Florida to give birth, Frazier said.

Relative to the West Coast, where surfers and kayakers have been attacked by great whites, the Lowcountry doesn’t have that much to worry about, Bell said. There are no sea lions here. Sharks eat sea lions; paddlers resemble them when viewed in silhouette from below.

“We’re not something that sharks over here consider a prey item,” Bell said.

There, feel better? Let’s not talk about smooth dogfish and spiny dogfish — two of the shark species that do winter here. In fact, Mary Lee also might have been following them to feed.

Reach Bo Petersen at 937-5744