MORE than 1400 of Scotland's precious natural treasures are in a poor condition, according to the latest official assessments released by the government's wildlife agency, Scottish Natural Heritage (SNH).

Some of the country's best-known mountains, lochs and woodlands, plus birds, beetles, plants and other wildlife, are suffering from threats including farming, forestry, sporting estates, pollution and invasive species.

Among the numerous natural features categorised by SNH as being in "unfavourable condition" are alpine and other plants on Ben Lomond, Ben Lawers, Ben Nevis, Glencoe and the Cairngorms. They are being eaten by excessive numbers of deer, burned off by landowners and damaged by walkers.

An oak woodland at Loch Lomond, an ash woodland at Aberfeldy and a native pine forest in Glen Affric have been damaged by forestry operations, invasive species and over-grazing by deer. Pollution is harming lampreys in the River Tweed, great crested newts and beetles in Dumfries and Galloway, and arctic charr in an Ayrshire loch.

Many bird populations are also rated to be in poor condition, including puffins and kittiwakes in the Firth of Forth, capercaillie at Glen Tanar in Aberdeenshire and arctic terns at Mousa in Shetland. Fisheries managers, foresters, farmers and invasive species are all being blamed (see table, right).

Scotland's protected wildlife sites are "our natural jewels in the crown", according to Lloyd Austin, head of conservation policy at the bird charity RSPB Scotland.

However, he added: "To see them being poorly managed or neglected and allowed to deteriorate is like skimping on maintenance of any other part of our heritage, such as Edinburgh Castle or the Forth Rail Bridge, and is completely unacceptable. We need to see action and additional investment."

SNH released its latest database to the Sunday Herald showing the state of more than 5200 natural features in 1800 wildlife sites spread across Scotland and protected by law. As of September 9, 2014, some 1444 features were defined as being in unfavourable condition.

The biggest cause of damage, affecting more than 1000 natural features, was invasive species such as bracken, gorse and rhododendron. Other major causes were over-grazing by deer and sheep, particularly on upland areas (affecting 866 natural features), recreational disturbance from vehicles and walkers (430 sites) and agricultural operations including the use of pesticides and fertilisers (239 sites).

Other pressures cited by SNH include water pollution, forestry operations, game and fisheries management, wildfires, waste dumping, infrastructure developments, mineral extraction and military activities. Birds of prey and freshwater pearl mussels are also said to be victims of wildlife crime.

Plants are suffering in many places for many reasons, and their status across the UK was the subject of a major report last week from the conservation group, Plantlife. It pointed out that only a tiny proportion of Scotland's woodland, heathland and grassland was included in the network of legally protected areas.

According to the report's author, botanist Dr Trevor Dines, the natural variety of the countryside is being lost to agricultural production. He said: "Sites are damaged or lost, habitats are fenced off and flower-rich verges are mown before they can set seed. Inexorably, the wild is being removed from our landscape."

Matt Shardlow, chief executive of Buglife - the Invertebrate Conservation Trust, pointed out that one of the sites rated as being in poor condition is Milton Loch in Dumfries and Galloway. He said: "It is shameful that the Government formally recorded that the loch was being damaged by farming in 1985, but nearly 30 years later these problems are unresolved."

SNH stressed that 79% of natural features are in a favourable state, slightly more than last year, though it previously said that there had been a "marked increase in the proportion of natural features which are being adversely affected by invasive species".

Brian Eardley, the organisation's designated sites manager, said: "We're leading a strong coalition of key public bodies, major non-governmental organisations and the private land management sector to tackle the problems."

A Scottish Government spokesman said that protected areas are some of the most important and at times fragile parts of Scotland's natural environment, adding: "We are working closely with public and private-sector partners and conservation charities to ensure that the condition of these sites is enhanced."