The Cairngorms Connect partners are working at the cutting-edge of conservation in Britain, on a larger scale, with a longer vision, and across a wider range of connected habitats, than any other project in Britain. Therefore, we expect to face new challenges and we need science to help us solve these.
We need to ask the question "Which techniques work best and are the most cost effective?" Where this is uncertain, then it makes sense to formally compare different management approaches side by side – testing different interventions within carefully designed field trials.
Re-establishing native woodlands by natural regeneration relies on nearby existing woodland to provide a source of abundant seed. This can be a very slow process in remote and higher altitude areas, which are so distant from current seed sources. Therefore, to speed up the process in such remote areas, we are planting and sowing small pockets of trees to establish an initial seed source, from which natural regeneration can then occur.
To work out how best to use this assisted regeneration method, we are comparing different options in a controlled management trial, replicated at nine sites across the woodland expansion zone.
We are comparing two methods of ground preparation: cutting the field layer with a traditional flail mower, vs cutting with a robotic cutter, with both methods designed to open up the ground layer to provide better conditions for young trees to establish.
Alongside this, we are testing the effectiveness of sowing seeds vs planting saplings. We are comparing all combinations of these cutting and sow/planting treatments and with areas subject to no management. This trial focusses on Downy Birch, Aspen and Eared Willow, and is taking place at the RSPB Scotland Abernethy Nature Reserve.
Image (above): Ring-barking Scots pine tree using hand tool as part of restructuring work in Abernethy Forest. Photo by Scotland the Big Picture.
Deadwood is a really important habitat for a natural forest ecosystem. It is vital for many forest-dwelling species, particularly fungi and invertebrates, such as the Pine Hoverfly, and birds, such as Crested Tits. Unfortunately, there isn’t enough naturally occurring deadwood in our forests due to past management practices so we’re looking at ways to create more.
We are comparing three different methods of creating deadwood and monitoring how these different techniques affect the deadwood beetle community, which are a good indicator of the effect the deadwood is having.
The three methods we’re trialling are:
We are monitoring deadwood beetle abundance and diversity throughout the summer, both before and after deadwood creation, in each treatment type, as well as in ‘control’ trees that will remain alive throughout the project. We will repeat this monitoring for several years after deadwood creation to help us understand how the different methods of deadwood creation influence the deadwood beetle community over time.
Image (above): The trailing stem of Twinflower, Linnaea borealis. Photo by Lizzie Brotherston.
We are working to restore two rare plant populations: Twinflower and Montane Willows. We are testing whether this work is successful at increasing the extent of these plant populations, and whether it is successfully increasing the genetic diversity of the existing natural populations, by enabling existing plants to breed with newly planted individuals.
Image (above): Twinflower, Linnaea borealis. One of our “Testing Interventions” projects will compare how twinflower seed production compares between patches that are, or are not, supplemented with transplanted twinflower individuals from elsewhere.
Twinflower (Linnaea borealis) is a nationally scarce but declining understory dwarf shrub. In Britian, it is only found in the north. The loss of its native woodland habitat has led to a 44% decline since the 1970s and it is now confined to just a few hundred sites in Scotland, mostly in ancient pinewoods in the north-east of the country with particular strongholds in Strathspey and Deeside. We are working to establish new Twinflower populations within the Cairngorms Connect area, as well as bolstering some existing populations to help ensure their survival.
Montane Willows form much of the habitat known as montane woodland. Montane woodland occurs high up in the mountains between the more familiar pine forests and the extreme harshness of the montane plateau. The Cairngorms was once a stronghold of this specialist type of woodland, but it is now largely missing from our landscape. We have used surveys to map the distribution of existing populations of Montane Willows and carried out genetic studies with the Royal Botanic Gardens in Edinburgh. These studies help us identify genetically different individuals that we can take seed and cuttings from to grow on in the Cairngorms Connect Tree Nursery in order to boost the population.
Natural forests are characterised not just by their species, but also by their ecological processes; these can include disturbances created by wild grazing mammals, or natural fires started by lightning. These disturbances are a normal part of a healthy, functioning habitat and certain species that survive in native woodlands are adapted to exploit and benefit from these ecological processes in order to thrive.
At RSPB Scotland Abernethy National Nature Reserve in the Cairngorms Connect area, we are mimicking some forms of missing natural processes in a trial using three 200ha plots of old pine forest.
In one area, we are introducing grazing cattle to mimic the effect of extinct large herbivores, and in another we are carrying out field-layer cutting to mimic the effect of natural surface fires. Field-layer cutting means cutting the Heather, Blaeberry, and other ground vegetation, using operating “Robocutter” machines. The third area will remain unmanaged, as a control plot.
