HONOLULU -- Divers monitoring tiger sharks feeding on a decomposing sperm whale off the coast of Oahu were surprised by a great white shark, a rare sighting in Hawaii waters.
The smaller sharks left when the possibly pregnant great white came to dine on the dead whale Tuesday, diver Ocean Ramsey told the Honolulu Star-Advertiser .
"She was just this big beautiful gentle giant wanting to use our boat as a scratching post," Ramsey said. "We went out at sunrise, and she stayed with us pretty much throughout the day."
Ramsey studies sharks, advocates for their conservation and leads cage-free shark diving tours. Ramsey and her team were working offshore from Sand Island with a permit from the National Oceanic and Atmospheric Administration.
Hawaii waters are usually too warm for great whites compared with California's Pacific coast, where they feed on sea lions and elephant seals, Ramsey said. She estimated this shark was more than 20 feet (6 meters) long and 8 feet (2.4 meters) across.
The giant white might have headed to Hawaii because of hunger and a need for extra nutrients in pregnancy, Ramsey said.
The shark could be the famed Deep Blue based on her size and markings, she said. Ramsey previously swam with Deep Blue on research trips to Guadalupe Island, Mexico.
"Big pregnant females are actually the safest ones to be with — the biggest, oldest ones — because they've seen it all, including us," Ramsey said. "That's why I kind of call her, like, a grandma shark."
Sharks usually only bite when they're curious or mistake people for their natural prey, she said.
While they're possibly gentle, great whites and tigers are apex predators and unpredictable, Ramsey said. Recreational boaters and divers should stay away from the dead whale site, she said.
Information from: Honolulu Star-Advertiser, http://www.staradvertiser.com