World Rainforest Day

Today on World Rainforest Day we dive into what makes Glen Nevis such an internationally important habitat and get some insight into our own slice of Scottish Rainforest from some of our team in the field at Glen Nevis, Alison Austin and Rob Cochrane. 

When someone talks about the rainforest, generally the first image that comes to mind is a tropical jungle filled with exotic creatures, oversized plant life that could be straight out of Jurassic Park and equatorial heat paired with frequent humid thunderstorms. However, in a small corner of forest in the North West of Scotland, a very different kind of rainforest exists; switching Brazillian Tapir for Red Deer, Macaw for Willow Warblers and Cocoa trees for Oak.

Where can you find a rainforest in Fort William?

Lochaber and Argyll to the south are blessed with some really great surviving examples of this kind of habitat. The John Muir Trust cares for a medium sized remnant of Scotland’s Rainforest in Steall Gorge in upper Glen Nevis. Other examples can be found out west on the Road to the Isles, on the Ardnamurchan Peninsula at Ariundle National Nature Reserve, in the Hidden Valley in Glencoe National Nature Reserve and at Taynish National Nature Reserve among many other places. 

What makes this forest a rainforest?

Short answer - it's very wet here! Despite the recent heatwave, the West Coast is a particularly rainy part of the world. We can blame the North Atlantic Drift for this, which delivers lots of cool, damp weather to us.

Scotland’s Rainforest is made up of the native woodlands found on our west coast in the ‘hyper-oceanic’ zone. There are other similar but extremely small remnants of this temperate rainforest on the western seaboard of Cumbria and Wales as well as parts of France and Spain.

When this rain falls over a particularly sheltered spot such as a deep glen or a sheltered north facing slope, it evaporates at a slower rate than at other more exposed locations. This creates areas that rarely dry out completely, creating a very humid environment. These pockets of humid woodland are what make up Scotland’s Rainforest 

The high levels of rainfall and relatively mild, year-round temperatures provide just the right conditions for some of the world’s rarest bryophytes - mosses, lichens and liverworts.

What species of flora can you find in the rainforest there?

The trees you can expect to find here are slow growing and often ancient. Hazel, Oak, Ash and Birch are some of the key species that make up this habitat, but we also often find Alder, Aspen, Pine and Willow too. The high humidity creates ideal conditions for bryophytes, many of which have become incredibly rare due to habitat loss.

Living alongside these are some fascinating fungi. Both fungi and bryophytes are often very slow growing. Some have even adapted to only grow on the bark of trees older than 100 years! All this moisture is also ideal for many species of insects (including biting midges...), which feed a diverse range of birds including Willow Warblers, Blackcaps and Redstarts. 

What dangers/issues does this area of rainforest face?

Sadly, Scotland’s Rainforest is thought by some to be even more under threat than tropical rainforests. Owing to the very specific conditions this habitat requires, and historic damage caused by humans, temperate rainforest covers less than 1% of the world. Today, the biggest threats to Scotland’s Rainforest are over-grazing and non-native invasive species.

High numbers of large herbivores, such as sheep, feral goats, roe deer and red deer, can cause ancient woodlands to enter a terminal spin decline by eating all the young seedlings. This means that as the oldest trees die there is nothing to replace them.  Non-native invasive rhododendron is increasingly dominating Scotland's Rainforest, suppressing tree regeneration and shading out the internationally important plants that form a key part of temperate rainforest biodiversity. Without action to remove and reduce these threats we could lose much of what makes these our rainforests special.

Fire is also a threat. Well-meaning campers often scour the forest for dead wood to burn. However, this dead wood is an equally important part of the ecosystem as it hosts many of the rare insects, fungi and bryophytes that call this habitat home. Should a campfire get out of hand and become a forest fire, the whole habitat could be lost and may take centuries to recover. Need to acknowledge that even though it’s always wet, it can still catch fire.

What have we been doing to look after this habitat?

Here at Nevis the team carefully monitor our rainforest to keep an eye on the overall health of the habitat. As with many other sites, we have identified that the levels of grazing from large herbivores, particularly red deer, are too high to allow the habitat to regenerate. Therefore, we've been carrying out deer culls informed by our monitoring results to reduce this pressure to a more appropriate level.

We are lucky not to have any non-native invasive species on our Nevis property but we work closely with Nevis Landscape Partnership who often coordinate clearing of non-native species on neighbouring land which could spread if not kept under check.

Our Rangers also work hard during the busy summer season to speak to campers and visitors on site and let them know about the damage fires can cause and the risks they create. We have introduced a strict 'no fires' policy on the land in our care as this could damage all the rare and protected habitats including the rainforest.

What can the public do to help look after this habitat?

Supporting our work and the work of other nature conservation charities is a great way to help these fragile habitats directly. You can get involved as a volunteer or support us by becoming a member. Even helping out with seemingly unrelated tasks goes a long way to supporting our work as it helps to free up our team's time to focus on the finer details of habitat restoration.

You can also help us out by being a responsible visitor - stick to the established paths and walking routes to minimize trampling of fragile vegetation and don't collect dead wood from the forest. Always check for wildfire warnings and never have a campfire when there is a high risk. 

The John Muir Trust is a founding member of the Alliance for Scotland’s Rainforest; a voluntary partnership of more than 20 organisations with a shared interest in “Saving Scotland’s Rainforest”. Since the Alliance first came together in May 2019, it has created a strategy that aims to secure funding for landscape-scale restoration projects, change government policy to support rainforest conservation, and raise awareness of this special habitat.

As little as 30,000 hectares of Scottish rainforest remain – a mere 2% of Scotland’s woodland cover and only one fifth of the area that has climatic conditions suitable for rainforest. If we don’t start taking serious and urgent action to support and protect our rainforest, we face the risk of losing this internationally important habitat completely. And the longer we wait, the harder it will become.

• Head to Alliance for Scotland’s Rainforest to find out more information on Scotland’s Rainforest and how you can help protect this incredible habitat.