Emily Puckett, who recently received her doctorate in the Division of Biological Sciences in the MU College of Arts and Science, found that certain species, like this Eastern Prairie Fringed Orchid, may wait as much as a decade or more to be listed as endangered. Credit: Joshua Mayer, Wikimedia Commons

The Endangered Species Act (ESA) was enacted by Congress in 1973 to protect species threatened with extinction. To receive protection, a species must first be listed as endangered or threatened in a process that is administered by the U.S. Fish and Wildlife Service. A two-year timeline for the multi-stage process, which starts with submission of a petition and ends with a final rule in the Federal Register, was established in 1982 by a Congressional amendment to the ESA. Now, a new study from the University of Missouri found that many species are encountering much longer wait times before receiving the endangered designation. Scientists studying the ESA believe that delays could lead to less global biodiversity.

"While the law lays out a process time of 2 years for a species to be listed, what we found is that, in practice, it takes, on average, 12.1 years," said Emily Puckett, who recently received her doctorate in the Division of Biological Sciences in the MU College of Arts and Science. "Some species moved through the process in 6 months but some species, including many flowering plants, took 38 years to be listed—almost the entire history of the ESA."

Findings are based on an analysis of 1,338 species listed for protection under the ESA between January 1974 and October 2014. Researchers analyzed the amount of time it took each listed species to move through the listing process. Researchers also analyzed whether a species grouping influenced how quickly or slowly it moved through the process. They found that vertebrates, including reptiles, fish, birds, amphibians and mammals had a significantly shorter wait time than did invertebrates and flowering plants. According to the authors, the finding suggests a bias in the listing process that contradicts the policies of the ESA.

"While the Service can account for species groups in its prioritization system, it's not supposed to be mammals versus insects versus ferns but, rather, how unique is this species within all of the ecological system," Puckett said. "However, our findings suggest some bias that skews the process toward vertebrates."

The delays in listing have real world consequences for endangered species. In the study, the authors cite previous studies that document species that went extinct due to a delay in the process. Likewise, a species that gets listed quickly and has a conservation plan put in place to protect it may have a chance to even bounce back. For example, the island night lizard was listed in 1.19 years, whereas the prairie fringed orchid took 14.7 years to be listed. The lizard has since recovered and been removed from endangered status; the orchid is still considered threatened.

"The whole point of putting species on the list is they already have been identified as threatened or endangered with extinction," Puckett said. "Without being on the list, we run the risk that these populations will go locally or globally extinct and there will be nothing to save."

The study, "Taxa, petitioning agency, and lawsuits affect time spent awaiting listing under the U.S. Endangered Species Act," appears in the early online edition of the journal Biological Conservation.

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More information: Emily E. Puckett et al. Taxa, petitioning agency, and lawsuits affect time spent awaiting listing under the US Endangered Species Act, Biological Conservation (2016). Journal information: Biological Conservation Emily E. Puckett et al. Taxa, petitioning agency, and lawsuits affect time spent awaiting listing under the US Endangered Species Act,(2016). DOI: 10.1016/j.biocon.2016.07.005