The move prompted concerns from conservationists that national parks could be short-staffed during the summer season, when millions of Americans usually visit.

At least 400 seasonal positions have been rescinded, but the number could be much higher as parks prepare for the busy season.

Trump’s freeze this time around is set to expire after 90 days, though agencies will first have to submit plans—in consultation with OMB and Musk’s Department of Government Efficiency—to permanently reduce their rolls through efficiencies and attrition. The Internal Revenue Service will face a longer freeze, per Trump’s order.