The US Fish and Wildlife Service (FWS) has routinely brushed aside advice from scientific experts when setting critical habitats for endangered species, according to a study published in the July issue of BioScience.

In setting the boundaries of critical habitats, internal FWS scientists are supposed to account for everything from the nesting tendencies of a species to its historical range. A draft habitat is then released for public comment, and a separate panel of outside experts reviews it before the agency sets the final boundaries.

But in a study of 42 critical habitats set between 2002 and 2007, the researchers found that the FWS ignored these reviewers 92% of the time, regardless of whether they recommended adding or subtracting land from the draft habitat boundaries.

“We’re seeing that they routinely ignored the scientific advice,” says Stuart Pimm, a conservation biologist at Duke University in Durham, North Carolina and a co-author on the study. “It’s a scientific integrity issue.”