Steve A. Johnson, PhD, Department of Wildlife Ecology & Conservation, University of Florida
Responsible pet ownership includes providing a safe and secure environment for the duration of the animal’s life—for some exotic animals (eg, tortoises, parrots), this commitment may exceed 30 years. In addition, exotic pets often have demanding husbandry requirements that may change as the animals grow. This makes caring for some exotics quite challenging, and many owners may not be up to the challenge. Too often, exotic pets escape or are intentionally released when owners tire of their novelty.
In a risk assessment study of exotic reptiles in Florida, researchers found that manageability (eg, housing requirements, aggressiveness, potential for escape) was a significant factor in explaining the likelihood of a species becoming established in the wild.1 Moreover, there are instances of unscrupulous pet dealers purposely releasing exotics with the hope of establishing a breeding population from which they can later harvest animals to sell.2 Many escapees or released exotics may perish in the wild, but under suitable environmental conditions they may survive and establish breeding populations, potentially with dire environmental consequences.
For example, Burmese pythons, previously a popular snake in the pet trade, are well established in south Florida and negatively affect native ecosystems, primarily feeding on mammals and birds (including the federally listed and protected wood stork and Key Largo woodrat), and occasionally on American alligators. There is evidence that these large constrictors are responsible for the decline of native mammals (eg, raccoons, opossums, bobcats, white-tailed deer) in Everglades National Park.3
Also breeding in Florida are several large species of lizards: the Nile monitor, green iguana, spiny-tail iguana, and tegu. These threaten native plants and animals and may become a nuisance to humans. All were initially imported via the pet trade. In fact, Florida now supports more than 50 species of breeding, nonindigenous reptiles—the vast majority (>80%) of which derive from the exotic pet trade.4 Moreover, the pet trade is also the dominant invasion pathway for exotic reptiles globally.5
And it’s not just reptiles—exotic fish, mammals, amphibians, birds, and invertebrates in the pet trade have become problematic. Lionfish, a popular saltwater aquarium fish native to the Pacific, are now established along the Atlantic Seaboard, in the Caribbean, and in the Gulf of Mexico where they are voracious predators of native reef fishes. Cane toads, now established in Florida as a result of escaped animals destined for trade, can cause severe illness and mortality in pet dogs that attack the toxic anurans. Monk parakeets have established populations in several states (eg, Florida, Texas, Connecticut). They construct large nests of sticks, frequently building them on power poles, which lead to electrical short circuits especially when the sticks are wet.
The cost of controlling and managing invasive species in the U.S. exceeds $120 billion annually.6 Considering these costs and the environmental damage that has resulted from escapes and releases of exotic pets, it is incumbent on veterinarians to do their part in the fight. Taking a sincere interest in and becoming more educated about the issue is the first step; next is sharing this knowledge with clients. When given the opportunity, discourage clients from purchasing an exotic animal, or at least insist they do their homework to determine which exotic species falls within their caretaking abilities. Finally, offer advice to clients who have an exotic pet they are no longer able to keep. Releasing the animal into the wild is never a viable option—it’s illegal and unethical.
For more information for pet owners, print and share this informational brochure: Options for Unwanted Pets.