Exploring environmental change in the Cairngorms with Patricia Macdonald

In October and November 2021 two crucial international conferences – one on the damaged state of ‘nature’, and one on climate change – will take the centre of the global stage: the UN Biodiversity Conference (Convention on Biological Diversity (CBD) COP15, Part 1), in Kunming (virtual), from 11 - 15 October; and the 26th UN Climate Change Conference, Glasgow, 31 October - 12 November (COP26). The two topics dealt with in these separate conferences are closely interconnected. It is only due to our human need to divide up the present single global-scale crisis to make it comprehensible that they are being discussed separately – nature recognises no such divisions.

In this feature, which will appear in three parts (of which this is the first – the others will appear during November), Patricia Macdonald (University of Edinburgh and Aerographica consultancy) takes as starting points three of her aerial photographic artworks from the collection of the National Galleries of Scotland, to consider environmental issues relating to climate change and biodiversity in the contexts of a series of key Scottish landscapes.

Braided river and Caledonian pines, Glen Feshie, Cairngorms, Scotland , 1988 - 2016 (triptych)

The same braided section of the River Feshie seen from the air in (left to right) 1988, 1995 and 2016, showing the large changes that continually take place in the size and position of the river channels and gravel bars

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The extent of ‘wild land’ is tiny in global terms today, but to experience it immersively, even for a short time – as an even tinier human – is not only unforgettable, but felt to be necessary by many people in an increasingly wounded world. The first three images seen above here, made overhead 57° 00’ 25” N, 3° 54’ 15” W, show a remarkable location far up a glen in the Cairngorms of the Highlands of Scotland. Arrival there on foot requires a long walk from any public road. The land here is a cultural landscape used by people over millennia, and therefore not truly ‘wild’, but it is nevertheless an exciting place to glimpse momentary views of ecological processes in action.  

The river

A dramatically braided river runs through the glen. The River Feshie drains the rainfall, snowmelt and gravel sediment from an enormous catchment of the highest and wildest Arctic-Alpine land in Scotland.

Water levels can rise and fall markedly even within a few hours, with storm-related flash-floods common, bridges carried away, and huge trees torn from the eroding banks and carried downstream, or beached and forming new islands.

The aerial images of the river seen here, made between 1988 and 2016, demonstrate this rapid aspect of the endless flux of the natural world. To stand on one of those spindle-shaped river islands with the dark, gemstone-coloured water flashing past all around is to experience directly the majesty of these processes in action and to perceive, fleetingly, the lineaments of Gaia (our ‘living’ planet). The more intense rainfall associated with climate change is expected to exacerbate the tendency of rivers, including the Feshie, to flash-flood, with even more dramatic results than in the past.

River Feshie: panorama

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Underwater in the river: boulders (left) and caverns

A veteran tree, which long stood as a snag, torn from the eroding riverbank, now forming a new islet

The woodland

Glen Feshie is also a place where a magnificent remnant of Caledonian pine forest is coming back to life – an example of long-term ecological resilience assisted by appropriate land management, following centuries of environmental degradation. 

The original woodland (pine, birch, rowan, alder, juniper and willows) was cleared for livestock, exploited for timber, and prevented from regenerating naturally by browsing deer, their numbers kept high – in the absence of top predators (wolf and lynx, made locally extinct by people in past centuries) – by the management priorities of recreational hunting AKA ‘deer-stalking’.

The hillside in Glen Feshie seen in the foreground in 1992 (top left) has no visible natural regeneration of pine, birch or other trees due to deer browsing pressure. The same view, seen in 2016 (top right) and 2021, shows natural regeneration of pine and birch increasingly well established after reduction in deer numbers

Late last century, this forest was in an almost terminal condition: the remaining veteran (‘granny’) Scots pine trees – the essential seed source – were dying. Outside fenced exclosures, very few seedlings survived to continue the woodland, and the peatlands on the higher ground were also damaged and eroding.

But recent changes in management, here and elsewhere in the Cairngorms and other Highland areas nearby, have reduced the density of deer, and a pulse of natural regeneration of trees – probably aided partly by gaps in other vegetation caused by the earlier heavy grazing – is now springing up, and the peatlands beginning to recover.

A mini-forest of pine and other tree seedlings has appeared in the most recent of the aerial views seen here, on some of the gravel bars and banks of the Feshie, although this may not survive the next flood.  

Elsewhere on the floor and sides of the glen, however, a burgeoning phase of multi-species regeneration, which includes returning ground flora and bird life (and salmon in the river), promises well for an enhanced environment that is diverse and robust enough to survive, and perhaps benefit from, future episodes of disturbance.

And in climate terms, both woodland and peatland are being strengthened as sinks for sequestering carbon dioxide from the air to help counteract climate change and its multiple dangerous effects.

A veteran pine in Glen Feshie in 1992 (left) above the sawn-up stump of another, and no visible natural regeneration of pine, birch or other trees due to high deer browsing pressure. The same tree and stump, now decayed, as that on the left, seen in 2016 (centre) and 2021 – natural regeneration of pine and birch increasingly well established after reduction in deer numbers

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Three views of the Ruigh Aiteachain area of Glen Feshie: in 1992 (left), showing minimal natural regeneration of trees (a lone pine sapling in a protective cage) due to high deer browsing pressure, and in 2016 (centre) and 2021, with good regeneration of pine after reduction in deer numbers

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Burgeoning growth of pine saplings around deadwood in Glen Feshie in 2021, below veteran ‘granny’ pines, taking place after a reduction in deer numbers has lessened browsing pressure on tree seedlings

Scots pine, Pinus sylvestris: needles (top left), canopy (top right) and shade

The future

But ecological communities, as in the past, continue to alter over time, due to climate change, either ‘natural’ or human-caused (anthropogenic), as well as human-caused disturbance (including the removal of their key members, whether top predators or sheltering woodland).

It is possible, if the climate of north-west Europe becomes increasingly ‘oceanic’ (rainy, with ‘mild’ summers and ‘cool but not cold’ winters), that pine forests will be forced to retreat into their northern and eastern heartlands, and other tree species may take over from pine. For this reason alone, it is important that a wide range of plant species should be encouraged to regenerate in the glen, even including, as part of the mix, species not within their current ‘natural’ range, like beech.

This might, in the long term, ensure that the newly regenerated woodland component of the enhanced environment in Glen Feshie, with its increased shelter and biodiversity, is not lost in the future.

Pinewood loss and natural regeneration, Glen Feshie: panorama

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Patricia Macdonald: Shadow self-portrait

Robin Gillanders: Angus & Patricia Macdonald
All photographs © Patricia & Angus Macdonald unless otherwise credited

About the author: Dr Patricia Macdonald FRSE is an environmental researcher; an Honorary Fellow of the University of Edinburgh and Edinburgh College of Art; and an eminent artist-photographer best known for her powerful aerial imagery, made in collaboration with her partner in the Aerographica consultancy, Professor Angus Macdonald, also of the University of Edinburgh. Her work is exhibited and published internationally, and held in public, corporate and private collections worldwide. She is the author / co-author of more than ten books / catalogues and numerous articles.

Explore further works by Patricia Macdonald on the National Galleries of Scotland website
Follow updates on the Aerographica website
Read more about Rephotography in the Scottish Highlands

12 October 2021