BOSTON -- Sharks may be some of the most bloodthirsty hunters of the sea, but animal-rights activists say humans have no reason hunting the fearsome fish and they want a well-known Vineyard tournament stopped.

The Humane Society of the United States is urging the organizer of Oak Bluffs Monster Shark Tournament, which is scheduled to start Thursday, to cancel its shark-hunting tournament in Massachusetts.

“It is time for a change in the way we view sharks and their protection,” said John Grundy, senior vice president for wildlife and habitat protection at The HSUS.

“We recommend that (the organizer), on behalf of more than 10 million supporters of the Humane Society, including the 191,300 members who live in Massachusetts, take a leadership position with respect to protecting sharks and cancel the Oak Bluffs Monster Shark Tournament,” he said.

The Humane Society said shark hunting is cruel and inhumane and sharks caught in the tournament suffer greatly when they're brought back to shore to be hung and weighed, sometime while they are still alive.

Monster shark tournament organizer Steve James, however, said shark hunting is not any crueler than any other kind of fishing.

“We used exactly the same equipment as any other kinds of fishing. The Humane Society just came after us because it’s a good visibility,” said James, of the Boston Big Game Fishing Club. “If shark hunting should be banned, all other kind of fishing should be banned as well.”

The tournament is scheduled for July 17 to 19 and James said he has no plans to cancel it.

More than 200 boats from all over Massachusetts are already registered to attend, which is about the same number as last year.

"There were 262 boats that participated in last years' tournament. We retained 24 sharks in the two-day tournament. But we released about 1,500-1,800 sharks in last year's tournament," said James.

"And there are hundreds of sharks out there. They are not in danger of going extinct in the North Western Atlantic," he said.

The Humane Society, however, cited a study by the International Union for Conservation of Nature and Natural Resources showing that thresher, mako and porbeagle sharks are threatened with worldwide extinction.

Blue sharks also have lost up to 70 percent of their worldwide population. The Huname Society said these kinds of sharks are the frequent targets of tournaments.

A 6 1/2-foot long young great white female shark was discovered on a Nantucket beach off Sheep Pond Road Monday.

John Chisholm, a biologist with the state Division of Marine Fisheries, examined the animal and said it will be dissected to determine the cause of death and collect other data.

It was the first time a great white had washed onshore in the Massachusetts area in about 20 years, officials said.