Too many retirements and not enough new hires are behind the drop in law enforcement rangers for the National Park Service.

According to Park Service officials in Washington, D.C., the agency hopes to boost law-enforcement personnel numbers through existing recruiting efforts. However, in the meantime parks are expected to assist each other when short-term staffing issues arise, said Park Service spokeswoman Linda Fryer.

"The recruiting efforts will address, at least in part, the decline in law enforcement rangers at the National Park Service,” she said via email on Monday.

Officials at Public Employees for Environmental Responsibility raised the issue of declining L.E. ranger ranks late last month, pointing out that Park Service figures showed that during the decade spanning 2005 through 2014 the number of permanent law enforcement rangers in the National Park System dropped by nearly 14 percent (from 1,548 to 1,322) despite both an increase in the number of park units and a substantial hike in annual visitors, campers and hikers.

The drop in seasonal L.E. rangers was even steeper, PEER reported. From 2006 (the first year full statistics were available) to 2014 there were nearly 27 percent (671 to 492) fewer seasonal rangers while “Peak seasonals” covering the peak month of August fell 7 percent (385 to 356) over that period.

On Monday, Ms. Friar said there were 1,329 permanent law enforcement rangers, and 425 seasonals, at the end of July. Not included in those tallies were U.S. Park Police numbers.

President Obama, in his fiscal 2016 budget request, asks that $2 million be appropriated specifically so the Park Service could hire additional law enforcement seasonal rangers for next year. If approved by Congress, this would come on top of $2.2 million that was approved this past year for seasonal law enforcement rangers.

Budget officers say 200 additional law enforcement rangers could be hired for FY16 compared to FY14 levels if Congress approves the president's request. However, the agency also would need an increase in funding to cover costs tied to health insurance for those seasonal rangers. Otherwise, the Park Service would have to find a way to absorb those costs within existing appropriations, something that could negatively impact the number of seasonals the agency hires.