The ubiquitous image of a lone polar bear lumbering across melting sheets of ice has come to represent the plight of endangered species everywhere. Surprisingly, despite the symbolic role that this species plays, citizens had to fight hard to get polar bears listed as “threatened” under the US Endangered Species Act (ESA). Although that decision was controversial, a new tally shows that citizen-driven ESA listings are just as valid as those identified by the pros.

One of the provisions of the ESA allows citizens to petition or sue the US Fish and Wildlife Service in order to get protection for a species or subspecies; the agency then conducts status reviews on the suggestions that appear to be warranted, then decide which deserve to be listed.

Critics of this controversial provision claim that most of the petitions and lawsuits are motivated by political interests, such as the intention to halt development. Detractors suggest that this stipulation of the ESA is not only unnecessary, but that it prevents money and resources from being used to protect the most vulnerable species.

A new study in Science used data from federal reports to determine whether listed species identified by the US Fish and Wildlife Service face greater biological threats than those listed as a result of citizen petitions or lawsuits. After examining the data for more than 900 species, the researchers found that species proposed via either petitions or lawsuits actually face greater biological threats than those identified by the federal agency.

Not surprisingly, petitioned and litigated species tend to be in greater conflict with development plans than those identified by the Fish and Wildlife Service; litigated species, in particular, are especially vulnerable. Habitat destruction is one of the major sources of biological threat, and this may explain why citizen-initiated species listed under the ESA tend to be particularly vulnerable.

So, while it may be true that political, rather than environmental, interests are driving some of these petitions and lawsuits, the citizen-initiative provision of the ESA does help identify species that are in jeopardy. In fact, since these species tend to be particularly imperiled, some might claim that citizens actually do a better job of choosing species for the list than do federal agencies. The researchers chalk this up to the fact that some citizens—such as scientists and non-profit groups—have more specialized knowledge about the local habitats and subspecies than the Fish and Wildlife Service.

However, this provision of the ESA is sure to remain contentious. Developers are constantly lamenting construction delays and projects halted due to petitioned species, and recently, groups have started creating controversial “bulk petitions,” some of which ask the government to list more than 600 species at once. For now, citizens appear to be doing a good job identifying at-risk species, but political, economic, and environmental motives may change that dynamic in the future.

Science, 2012. DOI: 10.1126/science.1220660 (About DOIs).