Arguably one of the most fascinating and biodiverse habitats in the UK Western Atlantic woodland is dotted along the western seaboard of Great Britain. I am fortunate enough to work on the conservation of this habitat in my day job. The following is extracted, with some additions, from a blog I wrote for the Woodland Trust
In this blog I shall summarise what the habitat is, where it can be found, the variety of wildlife to be found there and the threats it faces.
Defining the Rainforest
You guessed it the rainforest is defined by, well, rain. More technically it is in areas of high oceanicity where there is high rainfall and humidity and also where there is low annual variation in temperature. It also is sometimes referred to as Atlantic woodland. Generally the main composition of the woodland is oak in a mix with birch and ash. Hazel woods are an important canopy species in their own right and feature at many sites on the west coast of Scotland (Such as Ballachuan Hazelwood pictured above). Ravines and individual trees also create important features to form a mosaic of habitat niches.
Rainforests in the UK are best considered globally as part of the Coastal Temperate Rainforest biome. It is a habitat which is globally rare and some say is more threatened than tropical rainforest. The map below shows just how few places it occurs.
The areas where you get the conditions for this habitat to thrive in the UK are along the western seaboard. The key areas include the West Coast of Scotland, Snowdonia, Devon, Cumbria and Northern Ireland.
The rainforests in the UK are one of the most biodiverse habitats in the country. The high humidity and low temperature range create the perfect conditions for moisture loving lichens and bryophytes (mosses and liverworts). A good example of this habitat could contain over 200 different species of bryophytes and 100-200 species of lichen. Many of these species are ones which the UK has an international responsibility to protect due to their scarce global distribution. The key lichen communities include the Lobarion and Graphidion lichens. Probably the most recognisable is Tree Lungwort (Lobaria pulmonaria) which is a large leafy lichen common in this habitat. It literally looks like the lungs of the forest (Pictured below).
For more information on the lichens and bryophytes to explore in these woodlands see Plantlife guide to the species found here. There are also some really helpful identification tips in Bryophyte Guide 1, Bryophyte Guide 2 Lichen Guide 1 , Lichen Guide 2
This habitat is also home to lots of other rare and interesting wildlife such as the conservation priority species, Hazel Gloves fungus (Hypocreopsis rhododendri) (Pictured below), migrant birds such as pied flycatcher, wood warbler, redstart and tree pipit and butterfly species such as the chequered skipper to name but a few.
The rainforest was once a well utilised resource providing timber, charcoal and tannin for tanning leather. However our rainforest is threatened. It has suffered long term declines through clearances and conversion to other uses, now leaving a small and fragmented resource. It is also suffers two major threats in the form of the impact of invasive species and, as is the story in many types of woodland across the UK, high levels of grazing, primarily from deer.
Rhododendron (specifically Rhododendron ponticum and associated hybrids) has been called ‘the most damaging and most widespread non-native terrestrial plant in Britain’. A plant originally from the Iberian Pennisula, introduced to the UK c1760, It is an aggressive coloniser that reduces the biodiversity value of a site. It obstructs the regeneration of woodlands and once established is difficult and costly to eradicate.
The small and fragmented nature of the habitat also reduces its resilience against other threats such as pest and disease and climate change.
Where to See Rainforest
As shown above the key areas for the habitat are the West Coast of Scotland, Snowdonia, Devon, Cumbria and Northern Ireland. The Woodland Trust estate has some great sites where you can explore this habitat.
Name of the rainforest: Crinan Wood
Location: Argyll & Bute, Scotland
Description: With sweeping vistas across Loch Crinan to the romantic Duntrune Castle and the Argyll coastline, there can hardly be a wood with a more breathtaking outlook. Here, the moist, mild climate creates a temperate rainforest of ancient Atlantic oakwood, dripping with rare fern, moss and lichen, and brimming with wildlife, including the iconic red squirrel. Crinan Wood is one of our must-see gems.
Species that live there: Crinan Wood is teeming with wildlife and a visit to the woods and the wider area gives you a chance to tick off three of ‘Scotland’s Big Five’ iconic wild animals – red squirrel, red deer and harbour seal. Red squirrel are a common sight and seals can pop up almost anywhere along the coast. But to have the best chance of observing red deer, Britain's largest land animal, you need to stay downwind, and keep very quiet and still. Other species to look out for include bats, otters and, in spring and summer, the pearl bordered fritillary butterfly. Beavers have recently been reintroduced on Forestry Commission land close by. Crinan Wood also has more than 20 species of breeding bird including, tree pipit and redstart. Osprey may also be seen fishing nearby. Bird hides are scattered around the area, and local birdwatchers have spotted lots of species along the Add Estuary, just a short drive away.
Name of the rainforest: Coed Felinrhyd & Llennyrch
Location: Gwynedd, Wales
Description: In 2015, the Woodland Trust had the fantastic opportunity of acquiring Llennyrch, a traditional upland farm with an extraordinary surviving fragment of the rainforest at its heart. Together with the Trust's existing wood, Coed Felinrhyd (also know locally as Melenrhyd), this landscape has a place in Welsh myth and stretches from the shores of Llyn Trawsfynydd to the fringes of the Dwyryd Estuary. The steep banks of the Afon Prysor are thought to have been wooded for thousands of years; possibly since trees first re-colonised Wales after the last Ice Age. It’s a magical place with a rainforest feel that echoes with birdsong and where gnarled oaks are festooned with mosses and ferns.
Species that live there: The steep sides of the ravine are cloaked in sessile oak woodland with rowan and birch, with species such as ash, hazel and elm on milder soils. This woodland is designated as a SSSI for its Atlantic bryophytes, which thrive in the humid conditions of this rainforest. The quality of the lower plant flora is of European and indeed global importance, a fact recognised by its inclusion within the Meirionnydd Oakwoods and Bat Sites Special Area of Conservation. More recently, survey work has confirmed the site's international importance for lichen conservation. A number of rare species found here occur nowhere else in Wales and their presence indicates significant habitat continuity over many thousands of years.
...and in this blog the addition of a few other of my favourite sites. RSPB Scotland Inversnaid, Stirlingshire (Loch Lomond & the Trossachs National Park). A lovely drive in from Aberfoyle in the Trossachs or passenger ferry across the loch, Inversnaid is on Eastern shore of Loch Lomond. Its a great place to see the summer migrant breeding bird assemblage of pied flycatcher, wood warbler, tree pipit and redstart. If you're feeling really energetic the path also forms part of the West Highland Way...
Scottish Wildlife Trust Ballachuan Hazelwood (Pictured at the top of this blog and below). This site is on Seil Island, Argyll & Bute and is one of the best examples of Atlantic Hazelwood and full to the brim of lots of the Atlantic woodland specialist lichens
Glen Nant National Nature Reserve again in Argyll & Bute and a very accessible site close to Oban. Its a great place to see the chequered skipper and if you're lucky the day flying white-spotted sable moth (which myself and a colleague made a rare discovery of here a few years back). It also has great interpretation and reasonable grade paths.
To conclude, rainforest in the UK is part of a globally rare habitat and home to a vast amount of interesting wildlife. I would encourage you to go out and explore it for yourself. Unfortunately like many habitats it is threatened but work is underway n both Wales and Scotland to try and tackle these threats and conserve this hugely important habitat.