The Economics of Terrestrial Invasive Species: A Review of the Literature

Article excerpt

This paper reviews the literature on the economics of invasive species management as it applies to invasive species in general and terrestrial invasive species in particular. The paper summarizes a number of recent studies that assign values to the economic impact of terrestrial invasive species on a national scale. This is followed by a review of the economic literature on control and prevention of a biological invasion and the literature on international trade and trade policy with invasive species. The paper then reviews selected studies on terrestrial invasive plants, animals, and microbes, respectively.

Key Words: terrestrial invasive species, prevention, control, international trade, bioeconomic modeling

Throughout history the spread of plants, animals, and other organisms has been governed by natural ecological processes and has accompanied trade in goods and services and the movement of humans. As a consequence, species are continually introduced to areas outside their native geographic location and some of these species establish themselves as harmful invaders. Invasive species are one of the leading causes of global ecological change. Of 256 vertebrate extinctions with an identifiable cause, 109 are known to be due to biological invaders, while 70 are known to be caused by human exploitation (Cox 1993). In the United States, it is estimated that 40 percent of the threatened or endangered species are at risk due to pressures from invasive species (Nature Conservancy 1996, Wilcove et al. 1998). Invasive species also impose significant economic losses to consumer and producer welfare.

The problems associated with invasive species are not new and have long been recognized. U.S. invasive species policy dates to the Lacey Act of 1900. In recent years, however, increased globalization has led scientists and policymakers to focus more attention on the potential costs associated with invasive species introductions. Of the nearly 30 federal U.S. acts pertaining to invasive species, approximately half have been adopted since 1990 (National Agricultural Library 2006).1

As recognition of invasive species problems has grown, so has the economics literature. The purpose of this paper is to review the methodological literature on the economics of invasive species management as it applies to invasive species in general and terrestrial invasive species in particular. The paper is organized as follows. It begins with a summary of a number of recent studies that assign values to the economic impact of terrestrial invasive species on a national scale. This is followed by a review of the economics literature on control and prevention of a biological invasion. The section after that surveys the literature on international trade and trade policy with invasive species. The paper then reviews selected studies on terrestrial invasive plants, animals, and microbes, respectively. The final section contains brief, concluding remarks.

There are important aspects of the literature that are not reviewed here. The focus of this survey is only on terrestrial invasive species. Aquatic invasive species are examined in the companion paper by Lovell, Stone, and Fernandez (2006). In addition, this paper does not attempt an exhaustive survey of the numerous case studies of individual species in specific locations that assign values for control costs or damages or both. Many of these are referenced in the recent studies that value the economic impact of invasive species on a regional or national scale. These studies combine estimates of invasive species impacts from a large number of different sources whose reliability varies tremendously. It is beyond the scope of this paper to evaluate the assumptions that under lie each disaggregate estimate. Instead, it is left to the interested reader to consult the sources cited in the next section.2

A number of issues are closely related to the economics of invasive species. …