VORACIOUS rabbits, sheep and deer are munching their way through Ben Nevis and many of Scotland’s most famous wilderness beauty spots.
A quarter of the nation’s most important outdoor sites – including parts of the Cairngorms and Loch Lomond – have been seriously damaged, say the government.
Almost 250 of the 1000 sites of special scientific interest (SSSI) are in bad condition thanks to hungry herbivores overgrazing, trampling and answering the call of nature.
In some places, little remains but bare soil and earth.
The sites are vital because they provide homes to species such as capercaillie, wildcats, golden eagles and also sparse areas of pine forests.
Other damaged locations include the dunes of the Culbin Sands, Moray, the Cuillins in Skye and the slopes of North Berwick Law, East Lothian.
The SSSIs also include rivers and the banks of the Tweed have been damaged, potentially affecting salmon.
Nature bosses are now considering culling herbivores in the affected areas.
Paul Wheelhouse, the environment and climate change minister, told the Scottish Parliament: “Of the 957 SSSIs which could potentially suffer impacts by herbivores, 248 have been assessed as being in unfavourable condition due, wholly or partially, to the impact of herbivores.”
One report from Scottish Natural Heritage (SNH) stated that a 12km protected area around Ben Nevis is damaged “largely in relation to grazing pressure”.
This has caused rare plants to dwindle as well as the mountain’s last remnants of the Caledonian pinewood.
Large numbers of sheep have been removed “but it is not yet certain whether this has been sufficient to bring the habitats into favourable condition,” added the report.
North Berwick Law, a 614ft volcanic plug in East Lothian, now only has soily slopes as a result of “heavy rabbit grazing”, say SNH.
Creatures such as brown trout, otters and salmon are being affected by deer that devour the banks of the River Tweed.
The lack of plants means extra soil enters the water and changes its purity.
This causes a harmful knock-on affect to other animals who rely on the river as a home and food source.
A report shows nature bosses have fenced-off riverbanks to reduce grazing pressure in order to reduce “bank erosion and siltation of the watercourse”.
Nick Bullivant, head ranger for Cairngorms National Park, said rabbits have been a pest for the least ten years as they eat specially-made gardens.
He said: “They just appeared in 2001 when there was a lot of building work going on and they made a home out of underground pipes – now they have multiplied.
“We thought cold winters would kill them off or drive them out but they have survived and now they are coming out at night and eating special gardens that were set up for tourists to look at the natural flora of the mountain.”
The West Loch Lomondside Woodland also has “poorly developed” shrubs caused by “grazing pressure”.
The Cuillins mountain range in Skye – home to golden eagles – were pin-pointed as having a problem with deer.
But the Scottish Gamekeepers Association (SGA) warned against rushing to cull the culprits.
A spokesman said: “Before considering excessive culls, government agencies have to take the time to do accurate counts of the grazing animals.
“Gamekeepers are aware of the need to protect the flora of the region but there should be an acknowledgement that conservation works best when people are at the heart of it.”
SNH said they will implement “grazing management plans” – culls – to stop SSSIs being lost to hungry herbivores.
A spokesman said: “Where deer are the cause, SNH and partner organisations are in the process of negotiating with land managers to agree grazing management plans to reduce the pressure to a level at which unfavourable habitats can recover.
“It is important to ensure appropriate management of these sites as they represent the best examples of semi-natural habitat, host significant species populations or important geological features.
“They are refuges for many species which can not be found anywhere else in the United Kingdom or Europe.”