What happened: Officials from the Department of Interior (DOI) stripped language that was written by federal scientists on a key environmental impacts letter to the US Customs and Border Protection (USCBP) about the US-Mexico border wall. The deleted sections, written by federal biologists and wildlife managers from the US Fish and Wildlife Service (FWS), brought up scientifically-valid concerns about the potential impact of the border wall on endangered species whose populations are located along the border.

Why it matters: The protection of endangered species requires science, indeed, the consideration of science in listing endangered species is legally mandated by the Endangered Species Act. The exclusion of scientific evidence will likely put endangered species at risks of further decline. Furthermore, the deletion of scientific language sets up a dangerous precedent that it is all right to silence and censor federal scientists. Excluding scientists and their work from the policy making process leads to governmental decisions that are not evidence-based and therefore less likely to effectively protect the health of the public and our environment.

According to newly released emails obtained by the Washington Post, concerns raised by scientists at the Fish and Wildlife Service (FWS) about the potential harms to endangered species of building a border wall were excluded from an important document submitted to the US Customs and Border Protection (USCBP). In August 2017, the USCBP asked FWS to provide information on how animal species would be impacted by the construction of 60 miles of levee and bollard wall in Hidalgo and Starr counties, near the southern tip of Texas. The USCBP only received a truncated version of FWS scientists’ concerns. Officials from the Department of Interior (DOI) removed the scientists’ concerns on endangered species’ habitats, flooding risks, and wildfires from the final draft of the letter.

The FWS raised many concerns that were dismissed from the document submitted to USCBP. The scientists brought up the border wall’s potential ability to diminish the “habitat connectivity” for the endangered ocelots and jaguarundis. A permeant border wall may limit the cats’ access to drinking water and also increase the risk of inbreeding in the cat populations due to an inability for different populations to intermingle. The scientists also said that the border wall could trap the animals “behind the levee wall to drown or starve” during a flood and they suggested constructing a pathway south of the levee to allow the animals the chance to flee during a flood. Other concerns raised by the scientists included: capping the holes used for fencing posts so that wildlife does not become trapped in the holes, and to warn authorities that they will face difficulties when fighting wildfires in the parts of the US territory that end up south of the wall.

These concerns are largely in line with what scientists outside the federal government say and are the sort of issues that have been previously brought by the scientific community. Water is a limiting factor in the area and animals need to have the freedom to move to water-rich locations to find food and water. At the same time, the area is prone to flooding and the border wall is likely to trap wildlife and heighten the risk of drowning when the Rio Grande floods. The reduction in genetic species diversity due to the US-Mexico border isolating animal populations from one another is supported by scientific literature. Furthermore, over 2500 scientists from 43 countries agree that the US-Mexico border wall is a threat to biodiversity in the region. This threat is likely to be exasperated by the suspension of important laws in New Mexico and southern Texas that protect the environment, the wildlife, and the land.

Ocelot species in North America are precariously low, with the FWS estimating only 80 to 100 individuals exist in the region. The identification of one litter of healthy ocelot babies in southern Texas is considered a newsworthy event to the wildlife biologist community. The jaguarundi is also a highly endangered cat in the region. The jaguarundi are a threatened species in Mexico, but they are so rare in their range in Texas that the Texas Parks and Wildlife Department considers them extinct in the state, though the FWS lists them as endangered with habitat ranges in the southern tip of Texas.

A few of the concerns raised by the FWS scientists were included in the final letter. One concern focused on how the border wall would affect the tourism to a national wildlife refuge. Also included in the final letter were two concerns raised about the rare wild cat species – that the amount of brush that the cats need for traveling will be negatively impacted and that nocturnal cat may be disturbed by the lighting on the border wall.

The decision to strip away the scientists’ concerns may have been guided by earlier statements made by DOI Secretary Zinke. Jonathan Andrew, a DOI borderlands coordinator, previously wrote to FWS officials in a March 2017 email that, “The Secretary has indicated we are to support the border security mission so make sure you get any correspondence on this topic cleared up the food chain.” This is certainly not Secretary Zinke’s first time censoring scientists and their work, as recently detailed by our report about attacks on science at DOI. Federal scientists should be allowed to speak freely on these issues without the threat of censorship, and protecting endangered species requires the consideration of the best available science. Endangered species risk further decline when the best available science is not considered in decisions that impact their populations – and once these species are gone, we cannot bring them back. This not the first time that the Trump administration has ignored, dismissed, or quieted federal scientists that are raising scientifically-valid concerns (see here, here, here, and here). Without the voices of federal scientists speaking truth to power, our policies are bound to be less informed by the evidence and therefore less protective of the important animal species that also call the United States its home.