Re-Introduction of the Grey Wolf
Is there enough appropriate habitat in the Glen Affric region of the Scottish Highlands to sustain a re-introduction of the grey wolf (Canis Lupus)?
Introduction
The native Caledonian forest which was home to the grey wolf and covered most of Scotland was cut down to provide timber and fuel for human consumption and the forests only value to humans was as a resource for fuel and timber, areas were also cleared for agricultural and grazing land and over thousands of years the home of the grey wolf was eroded and is now all but gone (Puplett, D. 2007a)
Image 1. Grey Wolf (Canis, Lupus), in woodland (copyright Pitcher, J. 2007)
The extirpation of the grey wolf has caused a 'change' to Scotland's habitat over 'time', namely by removing the grey wolf from the ecosystem there has been no natural predator to control the deer numbers which has led to an increase in the deer population. These high numbers of deer (Image 2.) have also had a detrimental effect on natural forest regeneration by overgrazing and preventing re-growth.
"Red deer, through their excessive numbers and overgrazing, are sometimes seen as the main problem preventing the regeneration of the Caledonian Forest today. However, the ecological imbalance between native forest cover, numbers of grazing deer and lack of natural predators has been caused by humans, not the deer." (Pottie, S. 2000)
This change was brought about by human 'conflict' with the wolf, we humans carried out sustained persecution of the wolf over many hundreds of years, killing and trapping the wolves and burning the forests which they made their home. This demonstrates how we humans used our 'power' over the grey wolf to satisfy our own perceived needs to try and tame nature. Re-introducing the grey wolf to the Scottish Highlands would be humans using their power to affect positive change to the highland ecosystem by replacing this top level predator and maybe beginning to put right some of the damage we have done to the ecosystem.
Image 2. Red Deer (Cervus, Canadensis), on Rannoch Moor, Scotland (copyright Thompson,, A. 2008)
If the grey wolf were to be re-introduced into the Glen Affric region of the Scottish Highlands, would there be sufficient habitat to support it? This is the question which I set out to answer and if the re-introduction went ahead, would the deer population then be reduced to such a level that natural forest regeneration would begin?
Research
I began my research by first looking at the main source of food which the grey wolf would prey upon the red deer (Cervus, Canadensis) and their numbers in the Glen Affric region. The Deer Commission for Scotland (DCS) have a stated deer management objective of six deer per square kilometer. I have tried to compare the deer density figures for Glen Affric and also the surrounding area from the Deer Commission for Scotlands (DCS) 2003 deer count, to prey density figures which a pack of wolves would need to survive. This gave me an indication of whether there would be sufficient prey available within the area to sustain a small pack of wolves.
I have researched wolf ecology in the book 'Wolves: Behaviour, Ecology and Conservation' by Mech, L.D. and Boitani, L (2006), where I gained an understanding of the spatial requirements required by wild wolves as well as the habitat and prey requirements which I was able to compare to the Glen Affric region.
I also obtained information from the internet on wolves and the habitat requirements; I accessed the Trees for Life website. Trees for Life is a registered charity who are aiming to restore large areas of native wild forest in the Scottish Highlands as well as the extirpated species which once lived there.
Wolves and Humans Foundation who are also a registered charity also provided information on the role of large carnivores in the ecosystem on their website.
I have used the concepts of 'change' to the ecosystem over 'time' due to the disappearance of the wolf and growth in deer numbers and the subsequent damage which the deer cause to the regeneration of forest. Trees for Life websitecontained information relating to the effect of removing wolves from the ecosystem and the changes to the Caledonian forest over time due to human interference.
The book 'Wolves: Behaviour, ecology and Conservation' by Mech, L.D. and Boitani, L (2006), contained information of the impact on the deer population growth after wolves were extirpated and also the power of humans in wiping out the species using weapons and legislation to hunt and kill the wolf and eventually drive the species into extinction in Scotland. I have looked at what obstacles humans would need to overcome in order to use their 'power' to benefit the ecosystem and re-introduce the wolf and manage its habitat and development.
Discussion
The re-introduction of the grey wolf (canis, lupus) into the Glen Affric region of Scotland should not pose too much of a problem with regard to the topography and vegetation of the area because the grey wolf was once native to this area, however, over time humans have created 'changes' to the landscape over hundreds of years cutting down trees (Puplett, D. 2006b). Glen Affric and the Scottish Highlands in general would once have been dominated by native Caledonian forest, now there is less than one percent of native forest left due to trees being cut down by humans to provide fuel and timber and huge areas have been cleared for agricultural production and animal grazing (Puplett, D. 2006c). Glen Affric is an area which still has some of the remaining ancient pine forest as well as some commercial plantations.
Glen Affric is now a very different area (Images 3 and 4.) to what it would have been when wolves last roamed the area, so would wolves be able to survive in this changed landscape?
Wolves are found in many other parts of the world including Mexico, Southern Saudi Arabia, India and eastern Europe and they survive in various habitats, including desert, prairies, woodlands, swamps and tundra ranging from sea level to mountain tops (Fuller, T.K, Mech, L.D, Cochrane, J.F. 2006a). Wolves are extremely adaptable (Fuller, T.K, Mech, L.D, Cochrane, J.F. 2006b) and the types of vegetation available are not important to the wolves as long as there are large enough populations of ungulates (hoofed prey) available (Fuller, T.K, Mech, L.D, Cochrane, J.F. 2006c). Therefore due to the adaptability of the grey wolf I believe that it would be able to survive in the Glen Affric region so long as there was sufficient prey.
Glen Affric covers an area of approximately 300 - 400 Km2 and bordering Glen Affric there are similar areas such as West Benula, Glen Cannich, Strathfarrar and Strathconnon. This is a largely uninhabited area of mountainous terrain with very few roads covering in excess of 1600 Km2 so there would be minimal disturbance to the wolves by humans, although there may be some disturbance from recreational visitors to the area such as hillwalkers for example. The average size of territory which a small pack of wolves would require on the mainland with a prey density of 7 - 10 deer per Km2 would be 100 - 200 Km2 (Fuller, T.K, Mech, L.D, Cochrane, J.F. 2006d). As can be seen in Table 1. the deer density for these regions ranges from 12.79 - 17.24 deer per Km2, which means there would be sufficient prey available and a potential range for upto 8 or 9 wolf packs. Since wolves were extirpated there has been no natural predator to deer and so their population size has grown out of control.
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(Coghill, S. Deer Commission for Scotland 2008) |
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Re-introducing wolves would help to keep the deer population size under control and there is evidence that over time the health of the deer population would actually improve. Wolves would cull sick, weak or old deer simply because they would be easier to catch than a healthy stag (Puplett, D. 2006d). This would mean that fast healthy deer stand a greater chance of passing on their genes, therfore improving the speed and agility of future generations (Puplett, D. 2006e).
In 1995 there was a reintroduction of the grey wolf (canis, lupus) in Yellowstone National Park in the Northern Rockies, USA. Following the reintroduction during the late 1990's it was noted by biologists that the growth of willow and aspen along waterways began to improve, after being grazed upon for years by elk (The American name for red deer (cervus, Canadensis)), beavers moved in and wetland areas were formed, plants, insects and birds colonized these wetlands (Wolves and Humans Foundation 2008a). This is known as 'trophic cascade' where a change to a species high up the food chain has a knock on effect to the species lower down (Wolves and Humans Foundation 2008b). This natural regeneration of willow and aspen may not be because of a reduction in the number of the deer (Puplett, D. 2006f) states that:
"[the red deer] have become wary about grazing down by the rivers, where their view is limited; this forces them onto higher ground."
The deer become aware that there are predators in the area and this displaces them to other areas, if the deer are constantly moving around there is less opportunity to cause damage to vegetation.
With a suitable habitat in which to live and adequate prey levels available the outlook for grey wolves living in the Scottish Highlands looks good, but it was humans who drove the grey wolf to extinction in Scotland. If we reintroduce the grey wolf back into the wild there are no guarantees that there will not be conflict between wolves and humans again. Approval to reintroduce the wolf to Scotland would need to be granted by Scottish Natural Heritage (SNH) the government organisation responsible for wildlife and habitats in Scotland (Wolves and Humans Foundation 2008c). If in the future approval were given to restore wolves in Scotland, legislation would have to be put in place to protect the wolf from human persecution, but there would also be a requirement for compensation to be paid for example if a farmer lost a sheep due to predation. The reintroductions which have taken place in Yellowstone National Park and also other areas within the USA can teach us a great deal in how to manage such a project and by sharing best practice we would learn from the mistakes which they made. Ecological restoration is also an important aspect to wolf reintroductions, the wolves would cause sufficient displacement of the deer that natural forest regeneration would start to take place again. Humans may have to help this along however because some areas of the highlands are so barren that there are no local seed sources (Watson Featherstone, A 2001a). Trees for life who are already involved in the restoration of native Caledonian forest in Glen Affric suggest that for the reintroduction of wolves to be successful more work is required to restore native forestry and link these fragmented areas with 'biological corridors' of habitat creating a greater biological diversity within the species (Watson Featherstone, A 2001b).
Conclusion
Is there enough appropriate habitat in the Glen Affric region of the Scottish Highlands to sustain a reintroduction of the grey wolf (canis, lupus)?
My research leads me to believe that because the wolf is such an adaptable creature it would fit into the Scottish Highlands and with the large population of ungulates (hoofed prey) there would be no shortage of food. It is my opinion that the Glen Affric region is a suitable habitat for wild wolves. The conflict between humans and wolves which led to humans exerting power over the wolf in order to cause its destruction cuased changes to the habitat in the Scottish Highlands over time, namely the increased deer populations, overgrazing and damage to forestation. If a restoration of wolves went ahead the wolves would have to be managed and protected by government legislation. Habitat restoration in the Glen Affric region is already underway with the replanting of native Caledonian forest by charities like Trees fo Life. We humans used power to wipe out the grey wolf, it is time we now used our technological, political and legal power to reintroduce the grey wolf and improve the health not only of the deer population but also benefit the whole of the Scottish Highlands ecosystem due to trophic cascade.
References and Sources
Boitani, L. (2006), 'Wolf Conservation and Recovery' in David Mech, L. and Boitani, L.'Wolves: Behaviour,
Ecology and Conservation',University of Chicago Press. p183
Coghill, S., Deer Commission for Scotland , (o6 March 2008)'Re: Reasearch Project', email to Darren Wright.
Fuller, T.K, Mech, L.D, Cochrane, J.F, (2006a),'Wolf Population Dynamics' in David Mech, L.and Boitani, L.
'Wolves: Behaviour, Ecology and Conservation', University of Chicago Press.p163
Fuller, T.K, Mech, L.D, Cochrane, J.F, (2006b),'Wolf Population Dynamics' in David Mech, L.and Boitani, L.
'Wolves: Behaviour, Ecology and Conservation', University of Chicago Press.p163
Fuller, T.K, Mech, L.D, Cochrane, J.F, (2006c),'Wolf Population Dynamics' in David Mech, L.and Boitani, L.
'Wolves: Behaviour, Ecology and Conservation', University of Chicago Press.p163
Fuller, T.K, Mech, L.D, Cochrane, J.F, (2006d),'Wolf Population Dynamics' in David Mech, L.and Boitani, L.
'Wolves: Behaviour, Ecology and Conservation', University of Chicago Press.p163
Grewe, A. (2005a) 'Coire Leachavie from Mam Sodhail',[online] available from: http://www.armin-grewe.com/holiday/
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Grewe, A. (2005b) 'View over Loch Beinn a'Mheadoin',[online] available from: http://www.armin-grewe.com/holiday/
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