KNOWLEDGE YOU CAN USE

KNOWLEDGE YOU CAN USE
THE PERILS OF (EXOTIC) PETS!

Some significant threats to biodiversity may come from your own neighborhood. And they’re often aided by well-meaning small businesses: pet stores!

Question 16.10

Q: How might otherwise-responsible citizens wreak havoc on their enviornment? The purchase of exotic, non-native animals as pets can have unintended and harmful consequences if those organisms are released or escape into new habitats.

Question 16.11

Q: What’s wrong with keeping an exotic fish in your aquarium or a tropical bird in a cage? In an aquarium or in a cage, non-native species can be kept safely without harming any natural environment. But problems can occur if they escape, get flushed down toilets, are “set free” by owners who no longer want them, or, in some other way, get into the environment. And it’s not their native habitat.

Question 16.12

Q: What happens when non-native species are introduced to a novel environment? In some cases, non-native species do no harm. But in many others, non-native or exotic species can alter habitat and crowd out, outcompete, or directly prey on beneficial native species. They can spread exotic diseases, for which native species have no resistance. And they can disrupt and harm fisheries, crops, and other valuable industries, costing millions of dollars. Consider just a few common examples.

Fish. Catfish can alter river vegetation and shorelines, making them uninhabitable for native species. Lionfish from home aquariums have been released into the ocean off the coast of Florida. Expert predators, they kill a wide variety of smaller fishes, mollusks, and other invertebrates. In 2008, their population densities in some new habitats were found to have increased by 700% in just five years. China’s giant snakehead fish is a voracious eater and preys on numerous species of smaller fishes and amphibians. Traced to the aquarium industry, non-native populations off the east coast of the United States have wiped out numerous populations of native species. The snakehead fish can even crawl from one pond to another, surviving as long as four days out of water! Numerous other types of popular aquarium fish, including emperor angelfish, the yellow tang, and the orbicular batfish, have been found thriving in non-native habitats in the United States.

Birds. More than 150 non-native bird species have been documented in Florida, including 30 different parrot species, all of which were former pets, and many of which now cause significant crop damage, consuming fruits, berries, flowers, and seeds. Monk parakeets often build nests on electrical transformers and lampposts and have been responsible for power outages and other damage.

Amphibians and Reptiles. Terrapins (a type of turtle) and bullfrogs often outgrow their aquariums. If released into ponds, they can wipe out native fish, amphibian, and even small mammal populations.

Plants. Numerous popular aquarium plant species, such as the fast-growing seaweed Caulerpa, have become invasive in the Mediterranean Sea and in southern California. Freed from their natural predators, they thrive and have caused millions of dollars in damage.

Question 16.13

Q: What can you do? You can let your representatives in government know of the potential dangers of non-native species and the importance of closely monitoring the import of such species into the country—an issue that is not always high on their list of priorities. The best advice here, however, is—rather than simply avoiding purchasing exotic pets (or using non-native plant species when landscaping or planting a garden)—to become educated. It turns out, for example, that programs encouraging the export of tropical fishes from the Amazon can serve to reduce deforestation by giving local people the financial incentive to develop markets for renewable natural resources rather than carrying out activities that lead to deforestation.

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