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Public pressure effects species listings

  • Daniel Benjamin
  • Despite the law’s mandate, both
    economic and political factors
    are given considerable weight in
    decisions  to list species as endangered
    or threatened.

    The Endangered Species Act of 1973 (ESA) mandates that species protection be based on “scientific” criteria, not on political or economic grounds. Yet as anyone who has worked in Washington, D.C., can attest, laws are not administered in a vacuum. Research by Amy Whritenour Ando (1999) confirms that—despite the law’s mandate—both economic and political factors are given considerable weight in decisions to list species as endangered or threatened.

    The process of listing a species under the ESA is often both controversial and economically important. Listing the spotted owl, for example, ultimately ended logging on millions of acres of forests in the Northwest. Arguably, the listing of a species imposes both benefits and costs on members of the public, and both are usually greater the sooner the species is listed. Thus, persons who will be affected by a listing have incentives to alter the likelihood that listing will occur and to change the amount of time it takes for a given listing to occur.

    Groups seeking to influence U.S. Fish and Wildlife Service decisions can submit petitions and comments about a listing and ask congressional representatives to intervene. Ando studied both processes. Not all members of Congress are equally able to influence the Fish and Wildlife Service, and Ando focuses on legislators who sit on ESA’s reauthorizing subcommittees, because they are likely to have more power over the Service.

    Although there are technically several stages in the ESA process, Ando’s study focuses on the two stages that appear to be the most important in determining the duration and outcome of a listing decision. During Ando’s study period—the early 1990s—it took species about 2.3 years on average to pass through the initial (“category 1”) period, and an added 1.3 years to go through the second stage, the proposal period. But there was enormous variation around these means: from 1 day up to nearly six years for the category 1 period and from five months to more than three years for the proposal period.

    Ando finds that three key factors influence the length of time it takes a species to move through the category 1 period, as well as the probability that it will get through at all. First, if groups or individuals petition in favor of a listing and provide new information about the status of the species in question, then progress is more likely to occur, and that progress is likely to be faster.

    Second, the political stance of the subcommittee members in whose jurisdiction the species is located is important. Ando defines a “pro-environment” member as one who has a League of Conservation Voters (LCV) rating of 75 or above, and a “pro-land-use” member as one with an LCV rating of 25 or less. Working with these definitions, Ando finds that if the member has a generally pro-environment voting record, movement through category 1 is more likely and faster. If the subcommittee member’s record is pro-land-use, movement is less likely and will be delayed even if it occurs.

    Finally, Ando finds that Fish and Wildlife’s priority index also has an effect. This index is designed to summarize both the degree of threat to the species and its taxonomic distinctiveness, and it is avowedly “scientific” in its construction. Species with higher Fish and Wildlife priorities are more likely to reach the proposal stage and to get there more quickly.

    During the second key phase, the proposal period, a slightly different set of forces takes precedence. For example, having formal hearings on a species delays its progress, although the effect is small—six weeks. In addition, the emergence of any opposition to a listing is important: The filing of only one comment against, for example, is sufficient to delay the listing process more than three months.

    Overall, at low levels of pressure—say, 200 or so comments for and against listing a species—opposition tends to dominate support, resulting in listing delays among those species who had made it to the proposal period. When controversy is greatest, however—with 1000 or more petitions supporting and opposing—support for listing overwhelms opposition. This means that controversial species are likely to achieve endangered status the fastest.

    Like many public policy studies, the results of this one are of the “good news,” “bad news” variety. The bad news is that a process that is supposed to be purely scientific and above partisan politics appears to be subject to the same sorts of political pressure that drive other regulatory processes. Powerful legislators can influence the bureaucracy to move in ways that suit their interests. The good news is that despite Congress’s admonition against taking into account the costs and benefits of a listing, proponents and opponents of a decision are able to make their voices heard by the Fish and Wildlife Service. Whether the resulting decisions reflect any sensible balancing of these costs and benefits remains a question as yet unanswered.


    Ando, Amy Whritenour. 1999. Waiting to be Protected under the Endangered Species Act: The Political Economy of Regulatory Delay. Journal of Law and Economics 42(April): 29–60.


    Daniel K. Benjamin is a PERC senior associate and professor of economics at Clemson University. His regular column, “Tangents-Where Research and Policy Meet,” investigates policy implications of recent academic research. He can be reached at:

    PERC Reports, Volume 18, Number 3, September 2000

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