Today is Endangered Species Day, and to mark the occasion, 968 scientists from across the country sent a loud and clear message to the federal government: Keep politics out of conservation decisions. The scientists addressed a petition to Secretary of the Interior Sally Jewell and Secretary of Commerce Penny Pritzker, the heads of the federal agencies that oversee America’s land and natural resources and economic growth. The scientists asked that the federal government “place species conservation policy on firmer scientific footing” by using the “best available science.”

The signatories hail from different specialties, including mathematics, engineering, social science and, of course, wildlife biology and environmental science. The term “best available science,” they explain, means that policy decisions are made only after independent scientists with relevant expertise are able to evaluate the available scientific research, and that those decisions pass peer-review. It also requires that all parties in the process disclose any conflicts of interest.

A survey conducted last year by the Union of Concerned Scientists found that government scientists from the Centers for Disease Control and Prevention, the Food and Drug Administration, the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration reported that too much consideration was given to political interests in decision making. At the Fish and Wildlife Service, 73 percent of respondents reported that the influence of politics is “too high.”

A recent example of politics in environmental decision-making is the Fish and Wildlife Service’s choice to deny Endangered Species Act protection to the wolverine, which a federal judge said  “border[ed] on the absurd.”

“Of the numerous Western states which urged the service not to list the wolverine … internal service documents expose the likely motives—freedom from perceived federal oversight, maintaining the public's right to trap—behind the states' efforts against listing the wolverine,” U.S. District Court Judge Dana L. Christensen wrote in his 85-page decision throwing out the wildlife service’s 2014 decision.

A few weeks after that ruling, under similar political pressure, the wildlife service abruptly pulled plans to protect the Pacific fisher, a small mammal that is part of the weasel family, under the Endangered Species Act. A Freedom of Information Act request about this decision is pending.

The scientist’s petition must also be seen in light of the fact that the 114th Congress has already made more than 100 legislative attempts to weaken the Endangered Species Act. For plants and animals facing extinction, the Endangered Species Act is their last line of defense. And the act is wildly successful, preventing 99 percent of protected species from going extinct.

On this Endangered Species Day, we hope government leaders listen to scientists, for the sake of our wildlife and America’s natural heritage.