This post has been updated.
When SeaWorld fans defend the park against “Blackfish,” they tend to bring up what they see as a big logical inconsistency: If SeaWorld is bad, then so are all zoos and aquariums.
Indeed, zoos have largely ducked the criticism leveled at SeaWorld in the wake of the critical documentary, though they too house animals away from their natural habitats. Still, SeaWorld opponents mostly place zoos in a different moral category.
So what makes the institutions so different? Here are a few key distinctions.
SeaWorld and zoos both put animals on display – but their approach usually differs.
Go to most zoos today and you’ll likely see animals walking around the park or demonstrations that reveal some of their natural behaviors.
What you’re less likely to see are the elaborate shows  that are a hallmark of SeaWorld, where killer whales catapult out of the water, splash visitors and even dance with their trainers.
That hasn’t always been the case.
Jeffrey Hyson, a professor at Saint Joseph’s University in Philadelphia, has spent years researching the history of zoos across the world. Hyson said mid-20th century zoo shows often featured animals such as chimpanzees or elephants performing human-like hijinks.
Such displays were still popular when SeaWorld was founded in 1964 .
What sets SeaWorld apart is that it stuck with this model over the next few decades as zoos scaled back, Hyson said.
Many SeaWorld critics have visceral reactions to these shows.
Eliminating these shows is a central goal of a state Assembly bill  that would also end orca captive-breeding programs.
Backers of the bill compare the shows to circuses. They believe the performances exaggerate orcas’ natural behaviors and assign human traits to creatures with their own complex forms of communication and interaction.
SeaWorld and Grey Stafford, a former SeaWorld marine mammal trainer who now works at a Phoenix-area zoo, say the jumps, sounds and other behaviors the marine park’s killer whales display in shows aren’t all that unnatural. They also say the animals enjoy them.
Some experts and park visitors come away with a different conclusion.
“A show is just a circus show with lots of wild music and no context,” said Naomi Rose, a marine mammal scientist who has publicly supported a bill that would ban orca shows. She works for the Animal Welfare Institute , a Washington D.C.-based group that pushes policies that aim to reduce human-caused animal suffering.
For example, Rose said, unlike other members of the dolphin family, orcas only occasionally jump head first out of the water in the wild. When they do, they’re often in the process of trying to weaken or eliminate their prey.
Those leaps are central to Shamu shows. Rose, who’s spent years studying killer whales in the wild, said that behavior can be taxing for the orcas.
“It’s actually really hard for a killer whale to haul its whole body out of the water like that,” she said.
Most zoos are nonprofit organizations. SeaWorld isn’t.
SeaWorld is a publicly traded company that brought in $1.46 billion  in revenue from its 11 theme parks last year. (Three are SeaWorld parks.)
By contrast, San Diego’s world-famous zoo and many others like it are nonprofits that ostensibly reinvest any profits into their animals.
That simple fact sends a powerful message to many who love zoos but now refuse to go to SeaWorld.
“If we’re approaching these creatures with an eye to how much money can I get putting them on display, we’re kind of admitting that their relationship with the trainer is not the No. 1 thing,” said Andy Lamey, a UC San Diego philosophy lecturer whose focuses include animal ethics. “It’s the capacity to serve as a moneymaker.”
SeaWorld critics have been quick to pounce on such arguments.
But SeaWorld supporters, including Stafford, say these messages fail to acknowledge what SeaWorld gives back.
SeaWorld rescues hundreds of stranded or injured marine animals  each year though it doesn’t reveal what percentage of its revenue goes toward such work. Meanwhile, a separate conservation fund  affiliated with the company has provided more than $10 million in grants since 2003. The company also touts the work of scientists at its affiliated Hubbs-SeaWorld Research Institute .
Dale Jamieson, who directs New York University’s Animal Studies Initiative , acknowledged the significance of such investments but offered an analogy: The difference between zoos and SeaWorld is a lot like the difference between a nonprofit law firm that only serves poor people, and a corporate firm that spends a chunk of its time on pro bono projects.
“The issue in a way is that that’s not fundamentally what they’re about. At most, this is kind of a pro-bono activity they do to build some goodwill in the community, combined with the fact that many of the people that work at SeaWorld do care about animals and their well-being,” Jamieson said.
Nonprofit zoos, on the other hand, presumably put animal care, conservation and research above entertainment and profit.
“Blackfish” – and SeaWorld – taught us killer whales are large, smart animals.
SeaWorld visitors have long marveled at killer whales’ massive size and the social interactions between the animals and their trainers. Displaying that size – killer whales can weigh as much as 22,000 pounds  – and their bond with trainers are central to the spectacle of the Shamu show.
Then came “Blackfish,” which emphasized orca intelligence, plus the lifelong ties between orca mothers, calves and others in their family pods. One neuroscientist who appears in the film even suggests killer whale social dynamics may be even more intense than those of humans.
The movie also notes that whales traverse dozens of miles a day in the wild but are confined to tanks at SeaWorld.
Many readers have told me these factors persuaded them that it’s not right to hold orcas in captivity. Based on the film’s arguments, SeaWorld San Diego’s 10 killer whales  seem more likely to be aware of the suffering they apparently face, and folks I’ve talked to are weighing what, if anything, they can do to stop it.
So, the outrage directed at SeaWorld is two-pronged: “Blackfish” stoked concern for orcas in general, and SeaWorld’s orcas in particular. And SeaWorld parks house orcas, while most zoos don’t.
But humans have made similar connections with other large, social and intelligent animals that often live in zoos – namely, elephants.
A recent Scientific American editorial  called on zookeepers and marine mammal parks to free both creatures.
The magazine’s argument for nixing elephants at zoos is strikingly similar to the argument against orcas at SeaWorld:
Elephant mothers and their offspring form tight-knit clans in which they share parenting duties and shield children from predators. When a clan member dies, elephants mourn — there is no other word for it.
Zoos don’t necessarily see SeaWorld as playing for the opposing team.
Major zoos and aquariums belong to the same trade organization, the Association of Zoos & Aquariums , which promotes and essentially regulates its members through a rigorous accreditation process.
SeaWorld is also accredited by the AZA, and that’s translated into some big-name supporters. The company has often touted that stamp of approval when it’s attacked for alleged mistreatment of orcas.
This link has come in handy during social media battles too.
When “Blackfish” aired on CNN for the first time last October, thousands of viewers criticized SeaWorld. Some zoos fired back on SeaWorld’s behalf.
A spokeswoman for the San Diego Zoo, which didn’t join the SeaWorld social media cause, noted that the zoo often works with SeaWorld on conservation projects. They also participate in a UC Davis veterinary program that allows students to shadow animal caretakers at both institutions.
Spokeswoman Christina Simmons said the zoo is closely monitoring the so-called “Blackfish” bill.
“It’s a concern any time there is legislation that keeps people from protecting and building sustainable populations of endangered species,” Simmons told Voice of San Diego . “Our mission is saving species so it’s important to us that humans be able to continue work to save endangered species.”
Stafford, the former SeaWorld trainer who is now director of conservation at the Wildlife World Zoo & Aquarium  near Phoenix, told me his experience working for both entities left him viewing both similarly.
SeaWorld, like most zoos, engages in conservation and research efforts and both are regulated by the federal Animal and Plant Health Inspection Service , he said.
“In every sense of the word, in how the government views SeaWorld, it is absolutely the same as any other public display or aquarium,” Stafford said.
This is part of our Quest: SeaWorld  series digging into the park’s impact  on our region. Check out the previous story – San Diego Explained: SeaWorld’s Economic Impact  – and the next in our series – SeaWorld Visitors – and Ex-Visitors – in Their Own Words .