Invasive Species: A Brief Overview (CRS Report for Congress)
| Release Date |
Oct. 26, 2018 |
| Report Number |
IF11011 |
| Report Type |
In Focus |
| Authors |
R. Eliot Crafton, Sahar Angadjivand |
| Source Agency |
Congressional Research Service |
Summary:
An invasive species is a nonnative (also known as an alien)
species that does or is likely to cause economic or
environmental harm or harm to human health. The humanmediated
spread of species has occurred throughout history.
However, as society has become more globalized,
opportunities for the spread of nonnative and invasive
species have increased (e.g., trade shipments can carry
species and introduce them to many different regions of the
world). In addition, changing environmental, ecological,
and socioeconomic conditions could alter the risk for
invasive species introductions in the future.
Invasive species include terrestrial and aquatic plants,
animals, and microbes. Their introduction—whether
deliberate or unintentional—can pose threats to native
animal and plant communities, can lead to ecosystem
disruptions, and may contribute to extinctions of native
species. Invasive species also can directly cause or transmit
threats to human health. The introduction and spread of
invasive species also can result in significant economic
costs related to damages as well as management, mitigation,
and recovery activities. As of 2011, researchers at Cornell
University estimated that approximately 50,000 nonnative
species have been introduced to the United States, with
potential related costs exceeding $100 billion per year.
Inherent in any calculation of the costs of invasive species,
however, is valuation of economic and societal factors on
which expert opinion differs.
