PHOENIX (AP) — More people were rescued at the Grand Canyon in 2014 than in any year since 2001, with most being unprepared hikers, a park official said.

Half a million dollars was spent on 324 search and rescue operations at Grand Canyon National Park, according to spokeswoman Emily Davis.

"Last year, the reason we had the most call-outs in the canyon was actually for fatigue and hiker inexperience and physical inabilities," Davis said Tuesday.

Nationwide, the National Park Service spent $4 million of its $2.6 billion budget on rescues, KPNX reported (http://bit.ly/1QExil6 ).

About 2,600 search and rescue operations were carried out, or an average of seven searches each day.

A park's operating budget pays for rescues costing under $500, while a national pool of taxpayer funds covers costlier operations, Davis said.

While volunteers play significant roles on search teams, money is needed to cover food and equipment costs as well as park employees who lead the searches.

Park Service data indicates most of the calls made last year involved men above 50.

National Park Service search and rescue branch chief Ken Phillips said costs also go up if a helicopter or other aircraft becomes involved in a search.

With the beginning of summer and rising temperatures, Grand Canyon park officials are anticipating more search and rescue missions.

Phillips said calls involving lost or distressed hikers typically increase 60 percent when canyon temperatures hit 95 degrees. Many of the rescues are preventable if hikers prepare themselves and stay aware of their surroundings, he said.

"Aviators have a term they call situational awareness that's not only knowing what's going on around you but also taking the appropriate action," Phillips said.

He said hikers and visitors at any national park should check the weather ahead of time, map out hikes, research activities and carry water and provisions.