Bananas get everywhere: this one was on the summit cairn of Swirl How in the Lake District

It’s enough to drive a mountaineer bananas: Britain’s highest peak is being blighted by a thousand discarded skins as thoughtless walkers toss away the remains of their energy-boosting snack.

A working party from the John Muir Trust, which owns the summit and much of the land on Ben Nevis, worked out that more than half the rubbish they collected from the mountain was banana skins. Walkers mistakenly believe it is acceptable to throw the skins and other fruit peel on the hill because they are biodegradable.

Ben Nevis: carry your rubbish off the mountain

However, the discarded skins are a major problem for the trust and its volunteers. Even under normal conditions, the yellow skins can take two years to decompose. In the cold, arctic climate on the summit of the Ben, it can take much longer.

Now, the JMT has issued an appeal to all those who slog up the 1,344m (4,409ft) mountain: take all your rubbish off with you. Conservation officer Sarah Lewis said: “Banana skins are a particular problem because people think they will quickly disappear.

“Sadly, this isn’t the case. Quite simply, if you carry something up, you should carry it back down.”

Ms Lewis’s advice holds for all upland areas. Any food thrown away in the harsh upland environments of Britain’s mountains and fells can have an adverse effect on the delicate equilibrium of the species that inhabit the high grounds. Multiplied by the numbers involved in those visiting Ben Nevis, this source of food can tip the balance in favour of certain predators, starting a process that could see much larger changes over the decades.

All rubbish, whether considered biodegradable or not, should be carried off the mountain and disposed of correctly.

Anyone dropping fruit skins or peel on Scotland’s mountains could face a fixed-penalty fine of £50.

More exotic rubbish finds included this wheelchair. Sandy Maxwell of the JMT in the foreground with two volunteers

Banana skins are one of the more mundane items of rubbish found on Ben Nevis. Previous John Muir Trust working parties have discovered an old piano and a buried wheelchair. Other oddities to have found their way to the summit have included a Model-T Ford, a bed, a wheelbarrow and a barrel of beer. The JMT also cleared hundreds of unofficial memorials from the mountain. The scattering of loved-ones’ ashes has also proved a problem, the mineral-rich remains changing the chemistry of the thin soil around the fringes of the rocky summit.