Airlines aren’t fans. Federal authorities want to ban them. Fellow passengers heap scorn. Owners love their emotional-support animals, though — and the public can’t get enough of their exploits.

Remember Dexter the peacock, who earned fame for being denied a seat on a United Airlines flight? Of course you do. Same probably goes for Daisy the squirrel, whose owner got kicked off a Frontier flight. Coco the bunny recently made headlines around the world for a business-class trip she took in 2018.

The number of emotional-support animals on commercial flights soared from 481,000 in 2016 to 751,000 the following year, according to trade group Airlines for America. Unlike service animals, they are not specially trained to provide help for a disability, though they have essentially been treated the same way under federal law.

Critics say that has opened the door for travelers to abuse the system, bringing poorly behaved or even aggressive pets in the cabin — without paying a fee — by claiming they were providing emotional support.

Airlines have been adding restrictions in recent years, however, and this week the Department of Transportation proposed new rules that would let carriers treat emotional-support animals as pets rather than service animals. Service animals would be defined more narrowly as dogs that are trained to benefit a person with physical, sensory, psychiatric, intellectual or other mental disabilities.

[Department of Transportation proposes ban on emotional support animals on planes]

The public has two months to comment on the proposal, which could mean the end of headlines like “Daniel the emotional-support duck takes his first plane ride, soars in popularity.”

As we prepare for a future with fewer furry or feathered companions in the sky, it’s worth revisiting some of the most attention-getting cases in recent years.

The messy pig

A woman at Bradley International Airport in Connecticut was allowed to bring her emotional-support pig onto a US Airways flight in November 2014. But the goodwill didn’t last long. Fellow passengers said they were alarmed by the animal’s odor from the jump. And then, the unthinkable happened: The pig pooped in the aisle and started screeching when its owner tried to clean up the mess. A witness told CNN the woman started talking to the critter, which he estimated weighed 70 to 80 pounds, “saying it was being a jerk.” Citing the disruption, an airline spokeswoman said the woman (plus pig) were asked to leave.

Dexter the peacock

Dexter had his seat. He had his plumage. What the emotional-support peacock didn’t have, according to United Airlines, was the okay to fly. The carrier said the bird was prohibited from flying between Newark and Los Angeles in January 2018 because it “did not meet guidelines for a number of reasons, including its weight and size.”

The Associated Press reported that Dexter belonged to a photographer and performance artist from New York City named Ventiko, who had bought the peacock its own ticket for the trip. The bird’s Instagram account noted that the cross-country trip was still planned, only by car. Months later, in August 2018, People magazine reported that Dexter, “the world’s most famous emotional support peacock,” had died unexpectedly.

Gizmo the marmoset

Neither leg of an Ohio-to-Las Vegas round trip went well for Gizmo, a marmoset, and his owner, Jason Ellis, in August 2016. USA Today reported that on the first flight, Ellis failed to inform Frontier Airlines that he would be flying with the small monkey. A flight attendant ultimately spotted Gizmo peeking his head out from the owner’s shirt and asked for paperwork, which Ellis didn’t have at the time. Later, the airline acknowledged that the marmoset was an emotional-support animal, but that wasn’t enough to give Ellis an easy ride home. When he tried to catch a flight back to Columbus, the paper reported, Ellis discovered he was on Frontier’s no-fly list for not following the right procedures. He and Gizmo caught a flight home on Southwest.

Daniel Turducken Stinkerbutt, a duck

Daniel the duck — decked out in red shoes and a diaper — was greeted with something akin to reverence the first time he flew with owner Carla Fitzgerald in October 2016. She said employees posed for pictures with him and handed over a “Certificate of First Flight” on the first leg of their journey from Milwaukee to Charlotte. On the second, a short hop on American Airlines from Charlotte to Asheville, N.C., another passenger took photos and a video that eventually went viral and landed the duck on news sites including ABC, Cosmopolitan and, yes, The Washington Post.

[Daniel the emotional support duck takes his first plane ride, soars in popularity]

“I heard a few maybe semi-critical mutterings, like, ‘Now I’ve seen everything,’ ” passenger Mark Essig told The Post. “But most everybody was delighted to have a duck on a plane. As they should be.”

Coco the bunny

With a little white collar and black bow tie, Coco the rabbit was definitely dressed to earn an upgrade. Her owner, Takako Ogawa, registered her as an emotional-support animal and brought her on a flight from San Francisco to Japan in a carrying case, Insider reported. But when Ogawa had no business class neighbor, she let Coco stretch out. The passenger told Insider that staffers came by to visit the bunny and brought her treats. Although the flight was in 2018, the tale of Coco’s flight only started making headlines this month. Insider said the rabbit is not likely to repeat the journey: Ogawa said that at almost 9, Coco is getting too old for such jet-setting.

This rabbit on business class flight is probably the best thing you'll see today. 3年間のアメリカ生活、ついに終わってしまいました！ Cocoうさと2人で本日帰国です。I'll be working from the Osaka office for the next few weeks 🐰🍷 Posted by Takako Ogawa on Tuesday, May 1, 2018

Daisy the squirrel

A Frontier passenger informed the carrier that she would be bringing an emotional-support animal on her flight from Orlando to Cleveland in October 2018, according to the airline. But she apparently left out what, exactly, the animal was. An employee who noticed what was inside the cage asked the passenger, later identified by a Cleveland TV news station as Cindy Torok, to get off the plane.

[A woman brought her ‘emotional support’ squirrel on a plane. Frontier wouldn’t let it fly.]

She would not. That prompted workers to call police and remove everyone else from the plane. Torok ultimately left once police arrived, but she fumed at the treatment. She told Fox 8 Cleveland that employees threatened her with arrest and having the 11-week-old squirrel taken away if she didn’t leave the plane on her own. “I said: ‘You’re not taking my squirrel. Sorry, you’re not. I refuse. You will not take my baby from me,’” she told the news station.

Pebbles the hamster

This is a story the squeamish may want to skip, a tale of emotional support gone wrong. College student Belen Aldecosea said she confirmed with Spirit Airlines that she would be allowed to fly from Baltimore to Fort Lauderdale with her emotional support dwarf hamster, Pebbles. But when she showed up at the airport in November 2017, she discovered that the hamster would not be allowed to fly. Aldecosea, who was trying to get home to handle a medical issue, said someone from the airline gave her some brutal suggestions: set the hamster free or flush it down a toilet. (Spirit acknowledged that someone gave her wrong information initially, but denied suggesting the toilet option or any harmful outcome.) After trying for hours to figure out another way home, Aldecosea ultimately flushed the hamster down a toilet at the airport.

Read more:

DOT offers guidance for people traveling with emotional-support animals

United changed its policy for emotional-support animals. That peacock still can’t board.

Fur and fury at 40,000 feet as more people bring animals on planes