Too many lost hillgoers call 999 rather than use their own skills and experience to "sort themselves out", a rescue expert has said.
Mobile phones can help reduce the time of call-outs
Chris Lloyd, from Ogwen Valley Mountain Rescue in north Wales, said the misuse of mobile phones was leading to dozens of needless call-outs for rescue teams.
Mr Lloyd has estimated 30% of the calls to his team could be avoided.
Last weekend, the Ogwen and Llanberis teams had their busiest two days of the year, with six rescues between them.
Both teams also report a higher than average number of rescues this year.
Ian Henderson, from Llanberis Mountain Rescue Team, said they were attending more incidents every year, mainly because of the increasing numbers of people taking up outdoor sports.
He said his members had been called out 36 times this year, against a total of 70 incidents last year.
The Ogwen team has had 32 call-outs this year. The team was called out a total of 64 times in 2005.
WEEKEND OF RESCUES
Friday 21 April 1000 BST
A 55-year-old man is found by walkers in Devil's Kitchen area, collapsed.
53-year-old man has a heart attack on summit of Tryfan.
Policeman flown to hospital after he slipped and injured himself in Cwm Idwal.
Saturday 22 April 1300 BST
Climber stranded on Crib Goch.
Woman breaks ankle while walking up Snowdon via the Pyg track.
Walker dies after falling about 200ft near Snowdon summit.
Mr Lloyd told the BBC News website: "People rely on mobile phones these days. In days gone by, they would sort themselves out.
"Now people just jump to the mobile phone rather than think about their situation and how to sort themselves out.
"Rather than spending a wet night out or using some proper navigation and finding their own way down safely, they just press the button and call us out," he said.
"People are depending on them as the first line of defence. They will go out with no map and no compass and no whistle - but they have a mobile phone."
Mr Lloyd said every time volunteers were called out on a rescue it cost them money in fuel and often lost work time.
He said team members had joined mountain rescue to help out fellow mountaineers, but added it could be "tiresome" when people called them out "without thinking".
But Mr Lloyd said mobiles could be "invaluable" in some situations.
"They have reduced call-out time and I think they do improve the casualty survival," he said.
Instructions on how to treat injuries are often given by rescue teams over the phone before they reach the patient.
More and more people are taking up outdoor sports
Team members can also talk people down off the mountain if they become lost in poor weather or after dark.
Mr Henderson estimates mobile phones have "significantly" reduced call-out time for the Llanberis team.
"We can get called out much quicker. Before, it would take people three or four hours to walk down before we knew about it."
But he warned carrying a mobile was "no substitute" for climbers and walkers "being prepared, taking the right equipment and knowing how to use it".