Bedford Hills, N.Y., veterinarian Laurie Hess keeps a busy schedule, providing checkups, emergency services and other procedures for her patients, along with counsel for their human owners. But you won’t see any dogs or cats at Hess’s clinic. She limits her practice to lizards, ferrets, birds, turtles and assorted creatures, ranging from Chinese water dragons and Chinese pygmy hamsters to chinchillas and kinkajous.

Kinkajous? If you don’t know what these are, you’re probably not familiar with the world of exotic, or specialty, pets. (Answer: The kinkajou is an adorable little primate from Central and South America related to the raccoon. It hails from the rain forest and is sometimes called a “honey bear.”)

While cats and dogs are still tops in the world of pets, 19.4 million U.S. households owned exotics in 2013, according to the American Pet Products Association. The term “exotic pet” is loosely defined as anything but cats, dogs, fish or horses. For veterinarians, the category generally consists of reptiles and amphibians, birds and small mammals.

Some of the most popular are those on the tame end of the spectrum—rabbits, turtles, hamsters, guinea pigs and even poultry. Exotics often offer advantages as alternative pets. They can be suitable for people with allergies to furry things, and many require less space than cats or dogs.

“Some can be good starter pets for children, without requiring a lot of responsibility,” said Hess, who is board-certified in Avian medicine. “And some of them—like birds who talk—are fascinating!”

Still, Hess cautioned, some exotics require special care: Reptiles need certain levels of temperature and humidity that vary according to the animal, and birds require specially-formulated diets specific to the type of bird. “It’s important to have someone who’s knowledgeable about your animal and the food, housing, behavior and environment they need.”

Veronica Glickenhaus always wanted a furry critter around the house, but the New York City apartment she had shared with her husband before recently moving to Connecticut was only 500 square feet, and the couple are typically gone all day. So they decided to get a ferret, which spends 16 hours of its day sleeping yet is ready to entertain its owners when they arrive home at the end of the day. They brought Mordecai home from a pet store in 2012, then Abraham nine months later.

“They are more fun than I can possibly describe,” she said. “They’re constantly doing really silly things with each other or chasing me around, getting into my backpack, hiding things. And they’re really affectionate; they like to be held in my arms while I’m watching a movie.”

But the mischievous duo did require some lifestyle modifications and precautions. A huge cage, almost shoulder-height, was installed in the corner of the living room to provide plenty of space for the ferrets during the day, and the kitchen had to be child-proofed to keep the animals from getting under the refrigerator or into the dishwasher. “They’re like naughty two-year-olds!” she said.

But while a wide assortment of creatures classified as “exotic” make wonderful pets—in addition to the ones previously mentioned, an exotic menagerie could include gerbils and even rats to geckos, iguanas, nonvenomous snakes, hedgehogs, fennec foxes and geese—some exotic animals do not.

These include big cats, bears, primates and venomous snakes. The capuchin monkey that Justin Bieber owned before Germany confiscated it last August was undeniably cute, but owning one is dangerous and cruel, say animal rights organizations, who decry the illegal trade in animals who are best left in their natural environment.

The tragic potential of keeping wild animals was amply illustrated by a 2009 incident in Connecticut in which a woman’s face was torn off by her friend’s chimpanzee, as well as the killing of 50 exotic animals—including tigers, lions, bears, zebras and monkeys—two years later in Ohio after their owner released them from their cages.

“People get these animals when they’re very young, manageable and cute. But they grow up to be wild animals, kept in cages, chained up or loose. There’s just no good outcome there,” said Richard Patch, vice president of federal affairs for the ASPCA, which pursues regulation of wild-animal ownership and trade at both the federal and state level. “One python can kill a child. One primate can kill a human. These animals can be a danger to the community, degrade the environment, live miserable lives and end up a huge cost to taxpayers. Why?”

State laws regarding exotics vary widely; in some states, people can legally own almost any animal; in others, even seemingly innocuous animals like ferrets are banned. If you’re considering owning a pet, first check with both your state and county.

FORT LAUDERDALE, FL - JANUARY 22: Liz Barraco, exotic pet amnesty coordinator for the Florida Fish and Wildlife Conservation Commission shows off a red-footed tortoise and ball python during a call for people who own exotic pets like these to turn them in during the Exotic Pet Amnesty Program on January 22, 2014 in Fort Lauderdale, Florida.The program scheduled for Saturday is an effort to reduce the number of nonnative species being released into the wild by pet owners who can no longer care for their pets or no longer wish to keep them. Amnesty Day events are held around the state to provide the opportunity for people to surrender their nonnative pets free of charge with no penalties. Joe Raedle/Getty Images

FORT LAUDERDALE, FL – JANUARY 22: Liz Barraco, exotic pet amnesty coordinator for the Florida Fish and Wildlife Conservation Commission shows off a red-footed tortoise and ball python during a call for people who own exotic pets like these to turn them in during the Exotic Pet Amnesty Program on January 22, 2014 in Fort Lauderdale, Fla. (Getty Images) 

Then do some research about the animal’s requirements and risks to make sure it’s a suitable pet. Reptiles, for example, can carry salmonella and may not be appropriate for households with small children. Ferrets are prone to adrenal disease, which requires special medical care. At Hess’s clinic, one of only two in the country accredited by the American Animal Hospital Association, she even treats wallabies, marsupials similar to but smaller than kangaroos. They exude Aussie charm, but if you want one, be prepared to spend several hours a day with the animal in a pouch against your chest during the first months, which is essential to its well-being.

What you’ll pay for exotic pets varies as much as the pets themselves and will differ according to region, rarity and source. For example, parrots can range anywhere in price from $10 zebra finches and budgerigars to rare species priced at $10,000 or more. A green iguana might cost $40, an albino iguana $4,000. You can generally buy a ferret for $100 to $300 but a kinkajou could run you $2,500. And many exotics can be had for free, or for a small adoption fee, from rescue organizations such as the House Rabbit Society.

The best place to get information about exotics is from a vet who specializes in exotic pet care. You can find one on the websites of the Association of Avian Veterinarians, the Association of Exotic Mammal Veterinarians and the Association of Reptilian and Amphibian Veterinarians.

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