Commercial criteria to sell exotic species should be modified and buyers should be more responsible regarding this possession. Credit: Amphibians and Reptiles Recovery Centre of Catalonia (CRARC),

Abandoning exotic pets is an ethical problem that can lead to biological invasions that threaten conservation of biodiversity in the environment. An article published in the journal Biological Invasions, whose first author is the researcher Alberto Maceda Veiga, from the Biodiversity Research Institute of the University of Barcelona (IRBio), reveals that the release of invasive species in the environment has not been reduced despite the regulation that prohibits the possession of these species since 2011.

Other participants in the study, which goes over the regulation of the national catalogue of exotic , are Josep Escribano Alacid, from the Natural Science Museum of Barcelona, Albert Martínez Silvestre and Isabel Verdaguer, from the Amphibians and Reptiles Recovery Centre of Catalonia (CRARC), and Ralph Mac Nally, from the University of Canberra (Australia).

From buying impulsively to abandoning exotic pets

The study shows that, from 2009 to 2011, more than 60,000 causing trouble to the owners were recorded in the northern-eastern area of Spain, but these figures do not correspond completely to the animals that were abandoned. "The main reason people abandon their pets is because they buy impulsively, and some of these can easily reproduce once they are released", says Alberto Maceda, member of the Department of Evolutionary Biology, Ecology and Environmental Sciences of the University of Barcelona.

"In general, people get an animal very easily when it is young and cute, but when it grows up and causes trouble, they abandon it. Not all people do what it takes regarding the responsibilities of having a pet, it's a responsibility that lasts many years for those animals who live long, such as turtles."

Laws that do not stop this crime: Abandoning exotic animals

Since 2011, a law prohibits the trade, possession and transport of exotic species in Spain. The regulation has been effective to stop shops from selling species of crabs, fish, reptiles and amphibians that are listed in the regulation, but it has not prevented people from abandoning invasive species, the study warns.

"Apart from the species listed in the regulation, there are many others that are abandoned in the natural environment or are left in animal centers", notes Maceda. "The worst problem, however, lies in the exotic species that were commercialized massively years ago. This is the case of the known Florida turtles, which are really small at first, but when they grow, they are usually abandoned. The study shows that the legislative response takes a long time to make any effect regarding the release of invasive species which were sold years ago in this country. These measures are not very effective once the invasive species is distributed around the territory".

Although the law served to stop those species from being sold, "abandoning animals is another crime, and there is not any current legislation to solve this problem". "We cannot ignore -he insists- that releasing any pet in the environment is a risk, apart from not being ethical, and therefore, it has to stop", stresses the researcher.

Fighting for animal wellbeing and promoting a responsible possession of animals

Improving biosafety measures in livestock stabling centers, changing commercial criteria for the species and training buyers to promote a responsible possession are measures that could help reduce the abandoning rate. "It is necessary to create a record of owners, apart from making more educational campaigns. One option could be to require a certificate for the owner's training, as well as the use of microchips and special licenses to have certain species at home, and avoid the free access to species we know that could bring trouble to the owners".

According to the authors, importation of exotic species should be regulated, since nowadays it is only debated on when there is scientific evidence of a risk of biological invasion, or when there is risk of extinction for a species. In short, it would be necessary to list the species owners can have at home.

Not all exotic pets in the environment have been abandoned

Experts warn that prohibiting certain species can generate a response in the market that can promote the commerce of other with the same problems. A revealing example is the prohibition of the trade of the red-eared slider (Trachemys scripta elegans), which was introduced in the market of other freshwater turtles that brought similar problems to the buyers.

Also, not all exotic pets get to the environment for being abandoned. In some cases, the reason is a lack of biosafety measures -disinfection of waste waters, etc.- in companies that stable exotic species. Also, some legislative measures from the past have been controverted for the conservation of the environment: for instance, releasing —one of the most dangerous invasive species worldwide—to control the local populations of mosquitos.

"Regarding environmental problems, we have to be more proactive than reactive, and we are usually reactive. Pets -invasive or not- cannot be uncontrolled in the natural , let alone abandoned. Among other negative effects, they can hunt native species, and alter the natural habitat and can bring diseases that can persist in the native fauna even when the animal with the disease has already disappeared," concludes Maceda.

More information: Alberto Maceda-Veiga et al, What's next? The release of exotic pets continues virtually unabated 7 years after enforcement of new legislation for managing invasive species, Biological Invasions (2019). DOI: 10.1007/s10530-019-02023-8

Journal information: Biological Invasions