Twenty-five years ago, SeaWorld’s famous Shamu Show featured a lucky kid plucked from the audience who got to stand on a shallow ledge in the tank and toss a few fish to a killer whale.

Back then the scene was a crowd favorite.

Today the stunt — which SeaWorld halted in the mid-1990s — would seem about as safe as shoving a child into a lion’s cage.

Public opinion about orcas in captivity has evolved.

SeaWorld is changing, too.

But it may not be enough.

SeaWorld said this month that attendance is down at its parks in San Diego and Orlando. Executives fessed up for the first time that fallout from the controversial film “Blackfish” is part of the cause.

Wall Street didn’t react kindly. The company’s stock tanked 33 percent.

It seemed almost as if all of the bad publicity surrounding SeaWorld finally built up enough pressure to spring a leak in the stock of a company that went public just 17 months ago.

Hardly surprising, considering what’s happened between then and now.

Six of the original eight acts scheduled to perform at the park’s Bands, Brew & BBQ series backed out. Suddenly the likes of Willie Nelson and REO Speedwagon were appealing to visitors to stay away from the theme park.

Southwest Airlines and SeaWorld ended their partnership after 26 years, citing “shifting priorities.”

Now the same activists that barraged Southwest with petition signatures to ditch SeaWorld are targeting American Express.

And a pair of California lawmakers want to make it illegal to hold orcas captive, though that hasn’t gone anywhere yet.

SeaWorld is responding to the change in public opinion.

The company said last week that it will give up on a legal appeal that could have allowed its trainers to swim once again with orcas during shows.

The next day, SeaWorld announced it will nearly double the size of its whale tanks and give them a whole new look.

The death of trainer Dawn Brancheau in 2010 sped up this evolution of public opinion against captive orcas, but didn’t start it.

Criticism from fringe groups such as PETA was already getting more mainstream attention.

In 2009 a film called “The Cove” portrayed the cruel practice of dolphin hunting in Japan. SeaWorld says it doesn’t get its dolphins from such hunts, but it was criticized nonetheless for holding captive dolphins.

Brancheau was killed the next year by the park’s largest orca, in front of a crowd of horrified spectators. Then the agenda-driven film “Blackfish” called into question SeaWorld’s every practice related to killer whales.

SeaWorld Chief Executive Officer Jim Atchison concedes the park should have done more to counter the film.

Atchison is also right that SeaWorld has long been the industry leader in animal care and conservation.

But the standards are changing.

The National Aquarium in Baltimore is talking about removing its dolphins entirely and sending them to a yet-to-be-constructed seaside sanctuary.

“Our audience has evolved,” Aquarium CEO John Racanelli told Baltimore magazine. “Baby boomers grew up on ‘Flipper,’ but millennials grew up on ‘Free Willy’ and ‘The Cove.’ They are interested in these animals being treated more humanely.”

Chris Dold, SeaWorld’s vice president of veterinary services, says “sea pens” aren’t a more humane option because they can expose the animals to disease and other dangers they wouldn’t experience at a place such as SeaWorld.

Dold says the new, larger tanks for orcas will set a higher standard. The whales will receive better exercise from strong currents that will act as water treadmills. And the park is considering ways to change the water temperature and rotate obstacles for the whales to explore inside the tank.

“This will have many, many facets to challenge these animals,” he said.

That, the park says, will allow SeaWorld to continue its scientific endeavors that it says help animals in the wild.

SeaWorld is losing the public-relations war.

Whether it starts winning will depend on convincing people that its science is valuable enough to make holding whales in captivity worthwhile.

Photo Credit: Demonstrators from the People for the Ethical Treatment of Animals (PETA) protest against a killer whale's injury outside SeaWorld in San Diego October 3, 2012. Mike Blake / Reuters