Airlines are cracking down on the use of "emotional support animals" ó and their case could be strengthened by a woman who tried to bring a peacock onboard a United Airlines flight.First reported by The Jet Set, a travel-focused show, a woman at Newark Liberty International Airport in New Jersey tried to board a United Airlines flight with an "emotional support peacock" on Sunday. United Airlines denied the peacock , named Dexter, from flying because it "did not meet guidelines for a number of reasons, including its weight and size.""We explained this to the customer on three separate occasions before they arrived at the airport," an airline spokeswoman told the Washington Post Tuesday. @kumathedestructor took this great shot of me at #newarkairport today. Spent 6 hours trying to get on my flight to LA (after following all required protocol) Tomorrow my human friends are going to drive me cross country! Keep an out for us! #bestroadtripbuddy #dexterthepeacock A post shared by Dexter The Peacock (@dexterthepeacock) on Jan 27, 2018 at 7:01pm PST Many on social media sided with the airline and criticized Ventiko for her "selfishness" in trying to fly with Dexter. They complained that this incident makes it harder for people who actually need the animals."And this is why my friends who have service dogs canít fly without problems," Facebook user Karen Fuller wrote in the comments on a Jet Set Facebook post about the story. "Yeah no, Iím sorry but no. This whole comfort animal nonsense has skewed off on a tangent and needs to be stopped," another Facebook user wrote.Some users thought those criticizing Ventiko lacked a sense of humor."Oh darling Dexter, what a kerfuffle you have so innocently created. I think you are your girl are totally brilliant. I and my greyhound would so much rather sit next to you rather than next to any of those dreary sad people," Instagram user linda_may_miller wrote underneath Dexterís photo."I see youíre making headlines! I would much rather sit next to peacock than a screaming child or someone who falls asleep on my shoulder," another instagram user wrote. Related story: Fur and fury at 40,000 feet as more people bring animals on planesNot to be confused with service animals, emotional support animals , are animals used to provide emotional support for their owners and can bring some relief for symptoms relating to depression, anxiety and specific phobias.Unlike service animals, these animals do not necessarily have special training to assist people with disabilities.Service animals, as defined by the Americans for Disabilities Act, are specifically dogs that are individually trained to assist people with physical, sensory, psychiatric, intellectual or other mental disabilities.Examples include guide dogs that aid the blind, dogs that help assist people with seizure disorders or a dog that aids a person struggling with PTSD.Service animals are allowed to accompany their handlers anywhere, including places that have "No Pets" policies since a service animal isnít considered to be a pet under the law.Emotional support animals are not considered service animals under the ADA, so they have different laws to govern them.Federal guidelines allow for passengers with disabilities to board flights with a variety of animals. However, airlines can deny "unusual" service animals such as snakes and other reptiles, ferrets, rodents and spiders, the Washington Post reported.Miniature horses, pigs and monkeys require special consideration under the guidelines as airlines must decide if they would threaten the safety of other passengers or cause a disruption.Passengers who want to travel with emotional support animals could be required to provide documentation from a mental health professional. But these documents can be forged or gathered from questionnaire-style websites for a fee, according to ABC news.One passenger managed to bring a Turkey onto a Delta Airlines flight in 2016 under these federal guidelines, according to a post on Reddit.My neighbor is a flight attendant. He just posted this photo of someoneís "therapy pet," on his flight. from r/picsThe Department of Transportation noted that complaints related to service animals on flights almost quadrupled between 2012 and 2016, according to the Washington Post.On Jan. 19, Delta announced that it had enough and was revising its emotional support animal policy, citing a 150 percent increase from 2015 in passengers flying with the animals. The airline said it flew 250,000 service or support animals last year."Delta Air Lines is taking steps to further protect its customers, employees and service and support animals by implementing advance documentation requirements for those animals. This comes as a result of a lack of regulation that has led to serious safety risks involving untrained animals in flight. The new requirements support Deltaís top priority of ensuring safety for its customers, employees and trained service and support animals, while supporting the rights of customers with legitimate needs, such as disabled veterans, to travel with trained animals." Delta said in its press release.Starting on March 1, Delta will require customers wishing to travel with the support animals to show proof of health or vaccinations 48 hours in advance. All proof must be gathered within a year of the travel date. Passengers will also be required to have a letter signed by a doctor or licensed mental health professional.