One in Seven Imported Animal Species Pose a Potential Risk to United States

Simple, Inexpensive Tools Can Help Reduce Risk to Public Health, Environment

(08/01/2007) - WASHINGTON, D.C. – Federal agencies charged with overseeing the legal import of live animals across our borders are failing to take simple, inexpensive steps that could dramatically reduce the risks posed by these species to public health and the environment, a new report reveals.

Nearly one in seven non-native animal species that are legally imported into the United States pose a potential risk to native wildlife, human health or domestic animals, and some species could pose multiple risks, according to a report released today by Defenders of Wildlife. The report, Broken Screens: The Regulation of Live Animal Imports in the United States, details the proactive steps that the federal agencies charged with overseeing wildlife trade could and should take to reduce our risk. It is the most detailed analysis ever done of this trade.

“The U.S. is the world’s largest importer of live, wild animals,” noted author Peter Jenkins, director of international conservation at Defenders of Wildlife. “Yet none of the agencies responsible for overseeing this trade conduct comprehensive risk screening of non-native species before they are allowed into the country.”

Jenkins and his contributors discovered that the information needed to conduct preliminary screening is readily available, requiring minimal labor and financial investment to identify potentially harmful species. After reviewing 2,241 non-native animal species that were intentionally and legally imported between 2000 and 2004, Broken Screens concludes that at least 302 of those species have the potential to cause environmental disruption, economic harm or threats to human and animal health.

“The species that we identified as potentially risky have already come to the attention of scientists or regulators in the United States and around the world as known or potential invaders or as carriers of disease,” noted Jenkins.  “Yet our current regulatory system fails to address the vast majority of those 302 species.”

A number of legally imported animals are already wreaking havoc on U.S. ecosystems, and efforts to control these species costs the United States tens of millions of dollars every year, in addition to the ecological and economic harm they do. For example, Burmese pythons in the Florida Everglades are preying on vast numbers of native species. The infamous snakehead fish is turning up in streams and rivers and devouring native fishes. Other imported species are not yet causing problems here, but appear poised to, having already proven invasive and harmful in other parts of the world.

“The Nile perch, one of the fish species cited in our report, wiped out more than 100 native fish species within 30 years after it was introduced into East Africa’s Lake Victoria,” said Jenkins. “Similar ecological destruction could happen here in the United States where we have a number of lakes that could be colonized by illegally-released Nile perch.”

These non-natives species are not just invading our lands, lakes and wetlands, some are also spreading dangerous or deadly diseases. The Gambian giant rat, imported from Africa to the United States in 2003, carried the highly contagious monkeypox virus. Imported pet birds have brought in Exotic Newcastle’s disease, which could have a devastating impact on the poultry industry.    

“In the wake of the 2003 outbreak of SARS (severe acute respiratory syndrome), monkeypox, West Nile virus and concerns over avian influenza, it is unacceptable that the United States still has not put in place a more comprehensive system that reduces the risks of these and comparable new diseases entering our country,” said Dr. Katherine Smith, David H. Smith Research Fellow, Consortium for Conservation Medicine.

Broken Screens makes 11 recommendations to the three government agencies responsible for monitoring and regulating the international live animal trade, including the U.S. Fish and Wildlife Service, the United States Department of Agriculture’s Animal and Plant Health Inspection Service and the Centers for Disease Control and Prevention. The approaches advocated in the recommendations have been shown to protect native wildlife, public health and the economy in other countries that have experienced similar non-native species invasions. For more information on the economic impacts of non-native animal trade, please visit

Later this year, Defenders of Wildlife plans to convene a meeting of major stakeholders in the live animal trade, including the pet industry, regulatory agencies, researchers and public health experts, to begin exploring collaborative solutions to the problems identified in Broken Screens.

“It’s time to wake up to the risks posed by uncontrolled importation of non-native animals and close these regulatory loopholes,” concluded Jenkins. “With a small, cost-effective commitment of time and money, we can take the steps we need to take to conserve our nation’s natural beauty and diversity, and protect the health of our families, our communities and our domesticated animals as well.”

To read the full report, a summary of it, and other background information, visit


Defenders of Wildlife is dedicated to the protection of all native animals and plants in their natural communities.  With more than 900,000 members and activists, Defenders of Wildlife is a leading advocate for innovative solutions to safeguard our wildlife heritage for generations to come.  For more information, visit




Cat Lazaroff, Defenders of Wildlife, (202) 772-3270
Jared Saylor, Defenders of Wildlife, (202) 772-3255

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