Endangered species? Get in line.

The U.S. Endangered Species Act of 1973 (ESA) was signed on December 28, 1973, and provides for the conservation of species that are endangered or threatened throughout all or a significant portion of their range, and the conservation of the ecosystems on which they depend. Approximately 2,270 species are listed as endangered or threatened under the ESA but species must first be listed as threatened or endangered before receiving protection under the Act. In an attempt to accelerate the latter process, Congress passed an amendment in 1982 declaring a two-year timeline for the process, which starts with submission of a petition and ends with a final rule in the Federal Register.

But how close is this timeline to the reality? A group of U.S. researchers now evaluated factors affecting the number of species listed annually under the Endangered Species Act between 1983 and 2014. They used an information theoretic approach to assess whether listing budget, policy phase, or both factors were associated with the number of species listed and they calculated processing times for those.

While the law lays out a process time of two years for a species to be listed, what we found is that, in practice, it takes, on average, 12.1 years. 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.

It comes to no surprise that annual listing rates were positively affected by budget increase. However, the listing process for any species spans multiple years. Therefore, the colleagues also evaluated how taxonomy, the initiating organization, and lawsuits affected the duration of the listing process. They found that vertebrates had a significantly shorter wait time than did invertebrates and flowering plants. For example, the island night lizard (Xantusia riversiana) was listed in 1.19 years, whereas the prairie fringed orchid (Platanthera leucophaea) took 14.7 years to be listed. The lizard has since recovered and been removed from endangered status; the orchid is still considered threatened.

While the [US Fish and Wildlife] 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. However, our findings suggest some bias that skews the process toward vertebrates...Our results show that the process time from petition to listing would need to increase in speed 6-fold to meet statutory limits under the ESA. An increase in number of species listed annually, which currently stands at roughly 50 species per year, would be needed to provide protection to the hundreds of species not currently recognized as candidates, but that are in fact imperiled.