As of July 1, American Airlines’ passengers will not be permitted to bring along their frogs, hedgehogs or goats for moral support. The airline has issued new guidelines regarding therapy animals and will also require medical certification for all animals in the cabin.

The new rules include bans on amphibians, spiders, goats, snakes, non-household birds, tusked animals, as well as all unkempt animals. Though reptiles, hedgehogs, insects and rodents will be removed from the therapy animal list, miniature horses will not.

Emotional support animals are those that aid passengers suffering from anxiety, depression and panic attacks, among other psychological issues. Airlines rarely charge a fee for travelling with therapy animals if they adhere to a series of requirements.

"We support the rights of customers, from veterans to people with disabilities, with legitimate needs for a trained service or support animal," American Airlines (AA) said. "Unfortunately, untrained animals can lead to safety issues for our team, our customers and working dogs onboard our aircraft."

According to the airline, “service and emotional support animals must be able to fit at your feet, under your seat or in your lap (animals to be seated on lap must be smaller than a 2-year old child). For safety reasons, you won’t be able to sit in an exit row when traveling with your service or emotional / psychiatric support animal.

“Emotional support and service animals must be trained to behave properly in public; they must be tethered by leash and / or harness and under your control at all times. Animals won’t be permitted in the cabin if they display any form of disruptive behavior that can’t be successfully corrected or controlled.”

Delta and United also issued similar bans earlier this year. In part, this response comes as a result of the increase in requests for support animals to accompany passengers. In 2017, there were 75% more, or 76,000, applications. American Airlines, meanwhile, noted an increase of over 40% between 2016 and 2017. The air carrier will also require 48-hour advance notice and pre-clearance policy for all support animals, though there will be procedures for emergency bookings.

In January, a woman was denied entry with her “emotional support peacock” by United Airlines. She had planned on flying from Newark Liberty International Airport with the colorful bird.

"This animal did not meet guidelines for a number of reasons, including its weight and size. We explained this to the customers on three separate occasions before they arrived at the airport," United said.

AA employees have received training on how to determine the classification of each support animal. For companions that misbehave, a fee will be imposed, American Airlines added. “At American, we want to have policies and procedures in place that protect our team members and our customers who have a real need for a trained service or support animal,” the airline said.