Emotional support pets are allowed on airplanes, but the rules are quite lax when it comes to the species. A pet that has been given this title is one prescribed by a licensed mental health professional to someone with issues who requires the assistance of one of these pets to help ease their anxiety and allow them to focus on life. They are different from service animals and the Air Carrier Access Act allows these types of animals to join their owner on a flight.

RELATED: 10 Safest Airlines For Flying With Pets

You might consider an emotional support pet to be a dog or a cat, but some other people have different ideas as to what these critters might be. There are times when these pets are barred from flights, but that doesn't make it any less weird considering the circumstances. Keep reading to learn about ten weird pets people have actually taken on airplane flights!

10 10. Monkey

There is a man named Jason Ellis who flies with his emotional support marmoset monkey. He has actually been placed on Frontier's no-fly list after he forgot to provide the proper paperwork and identification for his primate prior to his flight. We can only imagine what it must have been like to see a monkey aboard an airplane, and what the reactions of the people around him must have been.

It might have looked cute to some, but others we can bet weren't so happy about the arrangement. We can all agree that this is one strange support animal, but we also want to know where we can find one for ourselves.

9 9. Kangaroo

Apparently it is not uncommon for a kangaroo to make the flight as an emotional support pet. We wonder if they only travel as youngsters or if adult-sized kangaroos are even allowed on flights, to begin with.

It is questionable when marsupials have begun to invade our airspace, but we also have questions as to where people find kangaroos in the first place. This is definitely not a common occurrence, but one we might not be so disappointed to see the next time we take a flight across the country.

8 8. Penguin

There were two penguins aboard a Delta flight back in 2012 for the premiere of Frozen Planet in New York. They were not emotional support penguins, but passengers did have a chance to take some pictures as the cute critters strolled up and down the aisles.

They had first-class tickets and the luxuries that provides passengers. This has happened from time to time as these flightless birds are permitted on airplanes time and time again in order to transfer them from one location to another with ease.

7 7. Pig

There are pigs who board flights as emotional support animals, but they are not always allowed to stay based on their bad behavior. There was one instance where a lady brought a large pot-bellied pig onto a flight and tied it to an armrest in the aisle.

RELATED: 10 Best Dog-Friendly Cafes In NYC For People Who Love Pups

The fellow passengers aboard the flight complained of its stench and its consistent pacing, so she was eventually asked to leave. There are others who sit on their owners' laps for the duration of a flight, but anything larger might want to be left at home.

6 6. Peacock

This peacock was denied access to a flight on Southwest Airlines, and we are still not sure if we are relieved or upset about it. The bird is undeniably cool, but we can only imagine how it would react to the changes it would experience as it took its first plane ride.

When the woman, who had been repeatedly told she could not fly with her peacock, was denied access to the flight she eventually drove it across the country. The only thing better than an airplane ride is a road trip with your favorite bird!

5 5. Duck

A peacock might not have been allowed on a flight, but ducks sure are. There are several instances of people bringing their emotional support ducks aboard a flight and they are adorable. Their cute little quacks and waddles would entertain anyone for a duration of time in the air.

We wonder how someone chooses a duck as an emotional support animal, but then again, maybe the duck chooses them. It is a strange coupling, but one we guarantee will only gain traction as this trend becomes more popular.

4 4. Miniature Horse

The U.S. Department of Transportation has declared that dogs, cats, and miniature horses should be prioritized as emotional support and service animals. They offer balance, support, and are fast learners which aid in their ability to help those in need. Their height, combined with their mild manners, make them the perfect companion on any flight.

RELATED: 10 Dog-Friendly National Parks to Explore With Your Pooch

The horses might release a few whinnies here and there, but you can bet they won't go sprinting down the aisle after someone else's support cat. It may seem like a strange animal to use, but we know you secretly want an emotional support miniature horse of your own.

3 3. Turkey

This may be one of the strangest pets aboard a plane you have ever seen, and we question there decision to have this as a pet. They are not cute by any means, and the face it gives you is downright creepy.

It obviously needs its own seat aboard a flight, but we have a hard time believing it was approved to board at all. The owner even used a wheelchair to move their pet through the busy airport, and we hope it didn't have any accidents on the flight. It might not be the bird for us, but for some, it is considered part of their family.

2 2. Tarantulas

This may not be an emotional support pet, but they are more common on flights than you think. People will sneak these onto planes in order to transport them from one place to another, and sometimes they manage to escape. It can be scary when they escape, but they are not deadly, even though their abdominal hairs can cause irritation.

We hope no one ever has to experience this atrocity on a flight, and if it does, make sure to tuck your pants into your boots to prevent them from thinking your clothing is a safe haven.

1 1. Snakes

You have either seen or heard of snakes on a plane, but there are some people who choose to bring them onto planes for fun. People usually want to transport them for sale, but rather than paying extra fees to have them stored with the luggage, they stick them in their carry-on bags.

This may not seem like a big deal, but proper documentation is required and they must be properly contained. There are certain occasions where the snakes do manage to get out, but luckily the incidents are far less deadly than that of the movie.

NEXT: 10 Flying Hacks All Seasoned Travelers Know About