(CNN) -- A marine science instructor's late-afternoon snorkel off the Southern California coast last Sunday was first met with shock and soon excitement when she discovered a gigantic oarfish, a deep-sea creature that remains little known to the science world and people outside.
Jasmine Santana was about 15 feet underwater when she found the 18-foot-long, silvery fish with reddish fins and eyes the size of a half-dollar staring at her from the sandy bottom. Realizing it was dead, she snatched the fish's tail, and using buoyancy and low tides, powered her way back on shore.
"I was first a little scared," said the still-thrilled Santana, who has been working for Catalina Island Marine Institute since January. "But when I realized it was an oarfish, I knew it was harmless."
After a 15-minute swim dragging the 400-pound carcass, she needed help from 14 others to lift the fish out of the water at Toyon Bay, California.
"I was really amazed. It was like seeing something in a dream," said Mark Waddington, the senior captain of CIMI's sailing school vessel the "Tole Mour" who gave Santana a hand. "It's the first time I ever witnessed an oarfish this big."
"Oarfish are found in all temperate to tropical waters, but are rarely seen, dead or alive," CIMI, a non-profit marine science education group, said in a release. "It is believed that oarfish dive over 3,000 feet deep, which leaves them largely unstudied, and little is known about their behavior or population."
Waddington, who has been with CIMI since 1994, said it remains unclear why the oarfish was found in shallow water this time, but it appeared to have died naturally.
Waddington said while the oarfish's carcass is still being preserved in ice, CIMI has been sending some of its tissues and other samples to marine scientists, including Dr. Milton Love, a fish expert from University of California at Santa Barbara, to study its DNA and diet habits.
Waddington said CIMI will likely to keep the fish's skeleton for educational purposes. Its program attracts more than 30,000 school-age children each year.