Brett Kavanaugh, President Trump’s pick to replace retiring Supreme Court Justice Anthony Kennedy, has already sparked concerns from Democrats on how his appointment could affect major issues like abortion rights, the Affordable Care Act, and the Mueller investigation. But, flying under the radar is an issue where Kavanaugh could make a big, and early, impact: the authority of the 1973 Endangered Species Act. If confirmed, experts worry Kavanaugh could threaten the landmark environmental law—and do it on his first day on the job.