Fruit-eating litter louts are a major problem, even at the highest altitudes.

According to the John Muir Trust (JMT), the wild-land conservation charity which owns most of the mountain, some 55% of the litter removed from Ben Nevis by its volunteers this year has been banana skins.

Many people believe the skins will quickly biodegrade or rot. But, because of the conditions on the upper sections of Ben Nevis, they could remain in their discarded form for years.

Staff at the John Muir Trust carried out a survey this month which suggested that up to 1000 skins may be present on the summit plateau.

It is asking the 200,000 people who climb Ben Nevis every year to be considerate and take all of their litter off the hill.

Sarah Lewis, John Muir Trust conservation officer for Nevis, said: "I am sure that the vast majority of walkers are responsible and take

their litter back down the Ben with them.

"But there is a significant minority who are littering and spoiling the experience for everyone else. Quite simply, if you carry something up, you should carry it back down.

"Banana skins are a particular problem because people think they will quickly disappear. Sadly this isn’t the case. We’ve often caught walkers in the process of chucking a banana skin on the path.

"When you speak to them about it they say it is not a problem because they will biodegrade. People would not so casually litter their local streets or green spaces at home with rubbish, so it is a mystery why they think it acceptable to leave them in such a sensitive mountain environment. There is a real lack of consideration for the natural landscape."

She said banana skins could take up to two years to rot on the summit, which, at 4406ft, is the highest peak in the country.

Because the mean temperature on the summit plateau of the Ben fluctuates between five degrees above and below 0°C, the process takes longer than it would at lower levels.

This is just the latest challenge for the JMT, which has owned the Ben since 2000. In 2005, plans were unveiled to establish a memorial garden at the foot of the mountain, so that people who wanted to commemorate loved

ones would not do so on the Ben itself.

Then, in 2006, it had to launch an appeal for people who had left plaques and other memorials to remove them. It had already begun to clear the numerous cairns to preserve the wild and remote feeling at the top of Britain’s highest mountain.

The cairns had increasingly been used as rubbish bins.