In what is fast becoming a winter tradition, opponents of the Oak Bluffs Monster Shark Tournament appeared before Oak Bluffs selectmen Tuesday to again ask that the town end its involvement with the controversial sport fishing tournament held each summer.

“It is heartbreaking people are encouraged to revel in the killing of these magnificent animals during this tournament,” said John Grandy, senior vice-president of the U.S. Humane Society. “This event is a travesty both to the animals slaughtered and to Martha’s Vineyard, which is cast [during this tournament] as a place that condones and encourages this type of savagery.”

The often emotional discussion was attended by approximately 30 people — including national animal rights officials. Although voters last year considered a nonbinding question at the annual town meeting asking whether the town should continue to host the tournament, there are no plans to put a similar question on the ballot this year.

Nevertheless, animal rights officials took the opportunity to criticize the tournament for being inhumane and cruel and implored selectmen to end the town’s relationship with the event.

Carter Luke, chief executive officer for the Massachusetts Society for the Prevention of Cruelty to Animals, said his organization became involved in efforts to save sharks three years ago. Since then, he said, shark populations around the world have declined substantially, just as research has emerged about the animal’s vital role in the ocean’s ecosystem.

As efficient predators, Mr. Luke said, sharks keep certain populations in check by hunting and killing other animals, particularly those that are weak or diseased. Without sharks, populations of other animals would swell to unsustainable levels, which would eliminate the available food in their ecosystems like phytoplankton, which produce a majority of the planet’s oxygen.

“There is so much we are learning about the natural world and how one species impacts the larger environment,” Mr. Luke said.

Charles (Stormy) Mayo, senior scientist from the Provincetown-based Center for Coastal Studies, said there is evidence that as many as a quarter of a million sharks are killed around the world every day. The sharks are killed for their fins, he said, which are used to make shark fin soup, a Cantonese delicacy commonly served as a symbol of wealth and prestige.

Mr. Mayo said at the current pace, the world’s shark populations will not be sustainable within a few years.

“What’s happening in our world’s oceans is a tragedy . . . and very little has been done to address the problem. Very few people think about protecting sharks — they are not cute or cuddly — and are not at the top of many people’s lists for protection.”

Mr. Mayo invoked the film Jaws, the blockbuster about a killer shark that was filmed on the Vineyard which, ironically, has helped shape people’s opinions of the much-maligned fish. “I have seen Jaws, but I have enough experience to know that we should not harm these animals,” he said.

Sharon Young, marine issues field director of the Humane Society of the United States, said people’s attitude towards sharks is slowly changing thanks to nature shows and specials like Discovery Channel’s Shark Week. Changing people’s opinions is vital to protecting sharks, she said.

“There is a saying by a naturalist that people will only protect what they love, and only love what they understand, and understand what they have been taught . . . many people think that sharks are big, dumb fish, and that’s simply not true.”

A small handful of people offered counterpoints to the anti-tournament sentiment.

Stewart Robinson, owner of Smoke’n Bones restaurant, noted that only a small number of sharks are killed during the tournament and argued that the event does have a positive impact on the town.

“You’re [talking about] taking away the biggest weekend in Oak Bluffs. I worry if we stop something like the Monster Shark Tournament — then what’s next? Do we stop duck hunting? Where does our personal freedom start?” he said.

Selectmen offered no comments during or after the discussion. Chairman Kerry Scott said members of the Oak Bluffs business association had been invited to next week’s selectmen meeting to share their thoughts on the tournament.