The most important component to preserve is predation itself


You can get figures, or soft cuddly toys, of any number of farmyard animals or domestic pets, and the occasional wild animal like a hedgehog or a squirrel, but I have failed to find any likeness of a fox, other than a comic soft toy, so that I may acknowledge its existence as the largest mammalian predator we have left in Britain. What is it about Britain that so miserably fails to understand and accept predation as part of wild nature, but persecute it often to extinction? As ever, North America offers lessons.

It’s a rare opportunity in Britain to get to hear a talk about the ecology of wolves given by one of the most highly cited experts in North America, and so I leapt at the chance when John Vucetich came to the University of Leeds in late March this year. It’s a pity more people didn’t turn up. Anyhow, Vucetich is a Professor in the School of Forest Resources and Environmental Science, Michigan Technological University, where his work on fusing ecological science and environmental ethics is inspired by carnivore conservation, and in particular the wolves and moose of Isle Royale (1). Vucetich was over in Britain as a Visiting Fellow of the Oxford Martin Programme on Natural Governance (2). A few days before coming to Leeds, he had given a plenary talk at the WildCRU Conservation Geopolitics Forum in Oxford on the role of ethics in solving interdisciplinary problems in conserving biodiversity, the principles of ethics when conjoined to engineering change in human behaviour offering a path towards resolving the lack of clarity, the underspecification between sustainability and conservation (3,4). His talk in Leeds was hosted by the Leeds Animal Studies Network, who will have noted his melding of ethics and science as being informative for the collaborative, interdisciplinary modes of research that the Network encourages, and which touch upon diverse approaches to the animal in the arts, humanities and sciences (5). Vucetich’s talk was billed as the Spring Keynote event of the Network, and promised a review of the ecological science to emerge from the wolves and moose of Isle Royale National Park, a Project entering into its sixth decade that he has led for 15 years, and is thus the longest continuous study of any predator-prey study in the world (6-8). Vucetich was also to highlight some implications of the research for the broader relationship between humans and nature.

The extent of browsing and the health of the woodland became a concern

The story of Isle Royale is well known to me, having written about it in 2007 in relation to what would happen if we got rid of the influence of farming from our landscapes (9). I noted the stunning comeback of wild nature of the deserted exclusion zone of Pripyat near Chernobyl after the nuclear disaster, the encroaching vegetation breaking up concrete and buildings, with wild boar being 10 to 15 times more common, as were big predators such as the wolf. I also explained what happened in Isle Royale National Park, a large island 45-mile-long and nine-mile-wide, in Lake Superior, surrounded by over 450 smaller islands so that it encompasses an area of 850 square miles including submerged land (10). What I was interested in was how wild nature adjusted when the landscape there was threatened by herbivores. In the early 1900’s, moose swam across to the main island, multiplying in their thousands where they had not been before, as they found the regenerating logged areas highly palatable browsing. Once the island became a National Park, the extent of browsing and the health of the woodland became a concern, leading park authorities to consider introducing wolves. However, the problem solved itself when during the cold winter of 1949-1950, the lake froze more extensively, and a wolf pack from Canada travelled over the ice and began predation of the moose.

I use one of Vucetich’s papers in my wilderness lectures to illustrate the spatial patterning of wolf kills on Isle Royale, the propensity of wolves to preferentially travel along waterlines, resulting in high-density predation zones in close proximity to water, such as a river drainage, an isthmus or a peninsula (11). This study also tied these high-density predation zones to an effect on biogeochemical processes resulting from decomposition of moose carcases, the nutrient inputs from decomposing carcasses causing rapid microbial growth in soil communities at the kill sites, which then mobilize organic detritus into forms available for plants. It’s a great way to get ecological concepts across, the science of wilderness, such as the behaviourally mediated effects of predation on wild herbivores like the moose, and the local impact on plant growth. I should perhaps also use a study from a decade earlier that monitored the shift in moose diet due to predator avoidance. In order to avoid predators, moose females with calves sacrifice the high quality diet available on the main island of Isle Royale by surviving on the wolf-free small islands throughout the growing season where the plant season is delayed by the cold water of Lake Superior (12). The data suggest that the wolves not only affect prey numbers by direct kills but also indirectly influence prey numbers by altering the diet of their prey, in this case, the reproductive females that contribute most directly to growth of the population, but which frequent poor feeding areas to avoid predators. A more up to date paper elaborated spatial variation in predation pressure by studying whether life history dynamics of moose on Isle Royale, and particularly their age-specific variation in habitat decisions, make them more prone to predation. The authors used evidence of age-related pathologies in wolf-killed moose carcasses of either osteoarthritis or diseased teeth, and made the correlation that the probability of kill occurrence for senescent moose, in comparison to prime moose, increased in high elevation habitat with patches of dense coniferous trees. These differences could be attributed, at least in part, to senescent moose being more vulnerable to predation and making different risk-sensitive habitat decisions than prime moose (see Section 10 in (13)(14)).

Vucetich took us through the biology of moose and wolves on Isle Royale. While cold adapted to withstand winters, moose lose weight during winter months when they only get to chew mostly on twigs from deciduous trees and shrubs, and the twigs and needles of balsam fir and cedar, while waiting for leaf growth to start in spring (15,16). Their greatest mortality from starvation occurs when this greening is late in coming. Moose spend eight hours a day foraging, and then a further eight hours regurgitating, chewing and re-swallowing to get the most out of their food. In contrast, wolves living in packs walk about eight hours a day at a speed of 5-6mph and commonly cover 25-30 miles, the reasons for the walking being to capture food and to defend their territories (17). A big, healthy, moose is safe from wolves – they will test moose a few times for a reaction and then walk away. If the moose runs, the wolves follow, with chases typically continuing for less than half a mile before they are grabbed by the nose, other wolves latching on – a wolf can support its weight by its teeth -slowing the moose and eventually stopping it by bringing it to the ground. This is a dangerous manoeuvre for the wolves and rib breakages are common. A wolf weighing 85lb can eat 15-20lb, then scavengers move in, foxes, eagles, and ravens are among the most important scavengers on Isle Royale. Most moose that avoid predation die of old age after nine years, although there are rare examples of moose living 18-19 years. Young moose are born to die, with 30-50% of moose calves being lost within six months of birth, but if they can survive past 10 months, they can go on to live for 5-7 years (see Section 13 in (13)). While wolves can live for up to 12 years, the average is four years, death coming from either starvation or from killing each other for food.

By 2017, there were maybe only two wolves left

A graphic of the chronology of events between 1959 and 2019 showed fluctuating populations of moose and wolves on Isle Royale. Vucetich took us through the most important events, stable populations of 500 moose and 20 wolves changing when a series of mild winters in the 1960s saw moose abundance doubled (see an animation of the chronology here (18)). Then a series of severe winters in the second half of the 1970s saw increased wolf predation, cutting moose abundance in half while wolves soared from 20-30 in three packs to 50. In 1980, humans inadvertently introduced canine parvovirus by way of a domestic dog, a disease also of wolf, and the wolf population crashed. With a reprieve from wolf predation, the moose population exploded to nearly 2,500 over the next 15 years, and with the growth rate of balsam fir plummeting. Vucetich believes this inter-relationship of change between wolves, moose and balsam fir constituted compelling evidence for the operation of a trophic cascade at Isle Royale (19,20). Over 1996, intense competition for a declining forage, an outbreak of winter moose ticks, and the severe winter, all conspired against the moose population which collapsed to below 1,000 leading to a high density of carcasses. Over the next 10 years, moose continued to dwindle, reaching below 500. However, wolves increase from a low of 10, albeit erratically, but getting a significant boost in 1997 when a sexually dominant wolf immigrated from Canada, effectively bringing an infusion of new genes. Over the next 10 years, the wolf population eventually stumbled as the moose continued to be kept low by high rates of predation, ticks, and hot summers, so that by 2011 the population was reduced to only nine wolves living in one pack, and six wolves of the socially disorganized remnants of what had been the Middle Pack. DNA analysis of wolf scats collected at kill sites indicated that there were no more than two adult females in the population, then they would be committed to extinction if those females were to die before giving birth to new females. By 2017, there were maybe only two wolves left.

Since the wolf population on Isle Royale was descended originally from just a single female and two males that arrived voluntarily to the island in winter of 1949-1950, then there was always a danger that it was going to be highly inbred, leading to inbreeding depression, a loss of genetic vigour which in the case of the wolves on Isle Royale has manifested in several different kinds of congenital malformation of the spine (see Section 12 in (13)). Vucetich seems to miss out the next immigration to the island that took place in 1967 when seven wolves were seen crossing the ice from Canada to the north shore of Isle Royale, four of which were black (21). However, the next arrival of only a single, new male wolf from Canada in 1997 offered only a temporary relief from the rate of inbreeding, Vucetich reckoning that it would need one fresh immigrant a decade to make a difference. Thus while the frequency of winter ice bridges to the island was high in the 1960s and 1970s – 7/8 years in 10 – that frequency had dropped and would continue to do so with climate change, thus begging the question of whether wild nature should be allowed to take its course, probably leading to the extinction of wolves on Isle Royale, irruption of moose leading to catastrophic loss of vegetation and consequent starvation of the moose leading to their extinction. Vucetich noted that extinction on small islands was a common, natural event, that as a natural event it could be perceived as a good thing, and therefore by extension that extinction is a good thing, but he saw this a naturalistic fallacy, a logical fallacy whereby a conclusion doesn't follow logically from what preceded it, as it is an error in reasoning. It isn’t anyway the case that extinctions on Isle Royale have been natural, as I have since found out that just prior to becoming a National Park in 1931, Isle Royale’s dominant large mammals were Canada Lynx and Woodland Caribou (21,22). Evidence from archaeological records indicate that these two species had been present on the island for 3,500 years, but both were removed by direct human actions. Caribou were extirpated from the island by hunting and lynx were removed by trapping. The last woodland caribou was seen on Isle Royale in 1925 and no animals have attempted to recolonize the island. Lynx were effectively killed off by the 1930s. Coyotes, having made it to the island by 1905, persisted on Isle Royale until the 1950s, when after decades of human persecution they ultimately disappeared. They undoubtedly, like the wolf, got to the island via the winter ice bridges.

It was at this stage that Vucetich brought in ethics in considering the appropriateness of intervention in Isle Royale (23) and what values were at stake in the efforts that were being made to introduce new wolves, which Vucetich described as the National Park Service intending to release 15 wolves on the island to bring the total up to 17. All I could think about at that stage, and which I commented to Vucetich, was the devastating effect that an irruption of moose would have on the balsam fir forests if more wolves weren’t brought in. He said some had raised that issue. I have since found that for others, it was about the fact that pretty much the whole of the National Park, bar a few docking and amenity areas, a total of 132,018 acres, was designated as wilderness in 1976 (10, 24). Views have been divided, with Marvin Roberson, conservation representative of the Michigan Chapter of the Sierra Club, saying that the decision by the National Park Service to go ahead with supplementing the wolf population on Isle Royale will lock the Park Service into a "dangerous cycle of manipulation”, that it was a “knee-jerk reaction” that the Park Service was pressured in to, that it is “restocking the zoo with the animals we like", and with Kevin Proescholdt of Wilderness Watch saying that human restraint is central to wilderness designation and so the National Park service can’t just pick and choose when to follow it (25):
“We can't just ignore a statute because everyone likes wolves. As soon as we drop the wolves out there, wild ends. At that point, it's no longer wild; it's no longer self-willed. It will make Isle Royale less wild and less free, and that's not what the Wilderness Act intended"

Natural processes will be relied upon to maintain native plant and animal species

Vucetich gave the impression that he was sympathetic to these arguments against intervention, and asserted that the National Park Service had had a policy of non-intervention for nearly a century. I knew this was not actually the case, as it was Starker Leopold, oldest son of Aldo Leopold, who changed the policy of management in National Parks with a report in 1963. In 1962, Starker Leopold was appointed as chairman to the Special Advisory Board on Wildlife Management by Secretary of the Interior Stewart Udall. The Advisory Board was responsible for writing what is known as the Leopold Report, a series of recommendations regarding wildlife and ecosystem management in the country's national parks (26). The report detailed the culling of elk in Yellowstone as a management process. Over a period of 27 years, the National Park Service had removed 8,825 animals by shooting and 5,765 by live- trapping; concurrently, hunters took 40,745 elk from this herd outside the park. Yet the range continued to deteriorate. Leopold presaged the return of wolves in Yellowstone, as his report recommended that as far as possible “control through natural predation should be encouraged” and this principle was incorporated into National Park Management policies. These policies have regularly been revised, the current (and extensive) version dates from 2006 where under Section 4.4.2 Management of Native Plants and Animals it has this (27):
“Whenever possible, natural processes will be relied upon to maintain native plant and animal species and influence natural fluctuations in populations of these species”

Vucetich also implied that the National Park Service, and particularly the Superintendent of the National Park itself, had done little to engage with the range of views. It was Vucetich’s opinion that instead of releasing 15 wolves all at once, which would abruptly force pack dynamics, it would be better to increase numbers gradually, although he seemed to suggest only one new wolf every 10-15 years, defending this by the impact that had been seen after that one, particularly sexually dominant male wolf that had come over the ice in 1997. I found myself wondering about how pack dynamics could be built from such a slow rate of addition, even given a probable rise in offspring, when what you probably needed was to bring in some less dominant wolves to make up numbers for hunting. I also wondered why inbreeding depression wasn't an issue for the moose on Isle Royale, as Vucetich didn't mention any new influxes to the island, but I didn't raise it with him. The National Park doesn't record any either, but instead note that because of their abundance, 70 moose were taken off Isle Royale in 1937 to restock dwindling numbers in Michigan's upper penninsula (21). I found it surprising that Vucetich was disapproving of the National Park Service, given what I knew about the deliberations there had been over the possibility of introducing wolves into Rocky Mountain National Park in response to the damage that the imbalance in deer populations was causing (28). Sure enough, when I was able to check, the Isle Royale National Park had started a public scoping exercise for what to do about the falling wolf population back in 2015, a consultation that included proposals about action on protecting vegetation, as well as whether to directly intervene by culling the increased moose population, or by increasing the wolf population (29,30). During the public scoping comment period, the park hosted four public open house meetings during the week of 27 July 2015 - in Houghton, Michigan, the home of Michigan Technological University where Vucetich is a Professor (see above); Grand Portage, Minnesota; and at the park in both Rock Harbor and Windigo (31). The public were also invited to comment during the consultation period by using the National Park Service’s Planning, Environment and Public Comment website, or by way of written communication.

In response to public comments received, and additional internal deliberations, a second notice of intent was issued for another consultation period, but with a narrowing of focus down to the question of whether to bring wolves to Isle Royale in the near term, and if so, how to do so (31,32). In similar vein to the Rocky Mountain National Park, the options in a draft Environmental Impact Statement that would be put out to that public consultation ranged from A: No Action; B: a preferred alternative of Immediate Limited Introduction over a three-year period with 20-30 wolves selected to maximize genetic diversity and initial predation rates; C: Immediate Introduction of between six and 15 wolves, including one or more established pairs or packs, with an additional four to six unrelated individuals, and with potential supplemental introductions over a 20-year period; and D: No Immediate Action, allowing natural processes to continue, but with Allowance for Future Action based on Alternative C (33). Vucetich was, in fact, given an early chance to comment on the various options put forward in the draft Environmental Impact Statement as a member of a team of eight Subject Matter Experts, and where one of his comments was about the challenge of managing for naturalness in the face of anthropogenic climate change – “An essential element of meeting that challenge is to specify and justify more precisely the purpose of management” (34). Having clarity about the exact purpose of each alternative was a repeated theme in Vucetich’s responses, as it had been in his plenary talk at the WildCRU Conservation Geopolitics Forum where he stressed the importance of understanding exactly what was the underlying purpose of actions (4). In that talk, he asserted that the issue surrounding wolf restoration on Isle Royale could be taken as a proxy for whether we should be mitigating climate change, that the National Park Service did not have a firm policy about mitigating climate change, and that they didn’t know with precision what the purpose of a protected area was.

In answer to a question to the Subject Matter Experts on what was the minimum number of wolves and of wolf packs desired for Isle Royale, Vucetich had responded that it depended on the overarching purpose of bringing wolves to the island – “If the purpose includes minimizing the risk of long-term damage by over-browsing, then it may be prudent to restore predation as an unimpaired force in a prompt manner. Prompt restoration would entail releasing more rather than fewer wolves. Between 8 and 12 wolves would result in relatively prompt restoration of predation shortly after they were released”(34). His answer to the relevance of the location of the release site in terms of individual animals or mated pairs was at odds with what he had said in his talk to us in that if the wolves were released in a more staggered fashion (a few at a time) the concern would be that the first wolves would establish a territory that occupies the entire island, making it a bit more difficult for subsequent packs to form. On the potential of climate change, Vucetich argued about an internal inconsistency in Alternative D that specified inaction through “allowing natural processes to continue” as he saw that the “wolf population on Isle Royale and the function of that population (predation) have been and continue to be impaired by anthropogenic climate change”. He was thus making a distinction about what was natural and what was anthropogenic, saying this reflected the challenge of managing for naturalness, perhaps because he viewed it as an ethical uncertainty here, but you could say that about the active interventions that were proposed and which are being carried out. Overall, his comments appear to be a willingness to be informative on the science in ensuring a successful implementation of an augmentation of wolf numbers on Isle Royale.

Minimizing impacts to the untrammeled quality of wilderness

The four alternatives of draft Environmental Impact Statement were put out to public scoping at two open house meetings in February 2017, one in Duluth, Minnesota, the other in Houghton, Michigan, as well as in two webinars (35) and again the public were also invited to comment during the consultation periods by using the National Park Service’s Planning, Environment and Public Comment website, or by way of written communication. Public responses during the two consultative periods are available (36,37) as are recordings of the webinars (38,39) as well as the Final Environmental Impact Statement that was amended and evolved as a result of the consultation (40). It was on this final statement that a decision was made, and published as a Record of Decision, signed by the Regional Director of the National Park Service's Midwest Region in June 2018 (41). This shows that the National Park Service had selected Alternative B, a time limited process of an “immediate introduction of a large enough number of wolves to fulfil the function of the apex predator throughout the 20-year planning period and allow the wolves to hunt, establish pair bonds, and ultimately establish packs. The selected alternative will introduce the historical average number of wolves on Isle Royale in an effort to have immediate effects on the island moose population, while minimizing impacts to the untrammeled quality of wilderness over the course of the planning period”. During a 3-year period of multiple and separate introductions, 20-30 wolves would be selected to maximize age, sex, and genetic diversity. The range in number gave scope to ensure adequate genetic diversity in the initial wolf population, so that the exact number of individuals would be determined based on available genetic data and assessment by subject matter experts. After the third year, if unforeseen disease or mass mortality occurs that decreases the wolf population to fewer than 12 individuals, and less than 3 breeding age females, then there could be supplementary wolves introduced for an additional 2 years. However, that 5-year limit on introductions is firm, even if the introduction efforts prove to be unsuccessful. Ecosystem monitoring will continue and the wolf population will again be reliant on voluntary immigration to the island.

I found that the first two wolves were introduced to Isle Royal last September, the 4-year old female and a 5-year old male coming from different pack territories on the Grand Portage Indian Reservation in north-eastern Minnesota (42). Two more females arrived in early October last year, then one female and three males were translocated from Canada in late February, and a further seven Canadian wolves, 3 females and 4 males, were translocated in late March, giving a total number of introductions of 13 to add to the two wolves that were already there (43-45). Unfortunately, in an update at the end of May, it was reported that the satellite positioning radio collar on a black-coated male translocated from Canada had been transmitting a mortality mode signal since March (46). However, National Park Service personnel had to wait a few weeks until the park reopened for the 2019 season to recover the carcass from the middle of Siskiwit swamp and determine the cause of death. The swampy conditions hadn’t helped, as the carcass was in a state of deterioration that made making an accurate cause of death difficult, but there were no apparent signs of injury or struggle. The loss of at least one wolf may have been expected, based on the approximately 25 % annual mortality seen in the wild wolves of the nearby Upper Peninsula of Michigan. Now, amongst the remaining 14 wolves, satellite location monitoring was showing that the new wolves were beginning to form loose associations with one another, hopefully as a prelude to pack formation. Thus a study had been initiated to look at predation this summer using satellite locations to determine clusters of wolves that may indicate that wolves have made a kill, are scavenging, or perhaps just resting. So how does this does this square up with what Vucetich appeared to recommend in his responses to the questions posed of the Subject Matter Experts group? When asked to describe ecological processes important to monitor so that changes in the system could be assessed, he responded (34):
“Isle Royale is characterized by a top predator that is un-persecuted by humans, an unhunted ungulate population, and a forest that is no longer logged. That circumstance – a food chain of large mammals that is entirely unexploited by humans is remarkably rare. Even in Yellowstone wolves have been killed often enough by humans to affect their behavior and often enough to be a non-trivial force on their population dynamics. The rarity of such a natural wonder and basic ecological phenomenon is the component of the ISRO [Isle Royale] ecosystem that is specifically the most important to preserve. The most important component to preserve, in this particular case, is predation itself”

Other than trusting to luck that there are immediately some successive bad winters creating land-bridges of ice across Lake Superior on which wolves might inquisitively reach Isle Royale, the preservation of predation that Vucetich seeks – at least for a few decades – has been met by the prescription of a limited intervention in this wilderness in augmenting the wolf population. It is a tough dilemma, with human meddling in wild nature written all over it, such as in the past the extirpation of lynx, caribou, and coyote from Isle Royale (see above) and now the changing climate reducing the potential for wolves to migrate across to the island, and worse still the suspicion from DNA testing that now rules out the moose having swum the 14 miles across from the Canadian mainland because they appear to be derived from moose in northeast Minnesota and North Dakota, combined with recently uncovered anecdotal evidence suggesting that 11–13 moose were captured in north-eastern Minnesota in 1907 and transported to the island by a private citizen’s group that may have intentionally stocked the moose onto the island for the purposes of recreational hunting (21,47). The only natural thing in this sorry story is thus the wolves voluntarily turning up and sorting out the mess of a trophic imbalance that humans had created, and which threatened the native forests of the island. Nevertheless, it’s a fascinating story about trophic ecology, the impact that large carnivores have, and the perils of island biogeography, the negative effect that isolated landmasses have on large carnivores through inbreeding depression and faunal relaxation (48).

Freely slaughtering an inconvenient wild animal

If only we could be faced with resolving such absorbing dilemmas in trophic ecology, when we have created such a mess in Britain, but do not have a large carnivore to bail us out. It’s not even often that our wild nature is seen in relation to the natural process of predation in trophic ecology – I wrote about a rare incidence back in 2014 when I highlighted two papers that had been published on the back of evidence arising out of the Randomised Badger Culling Trial that looked at the ecological consequences of the removal of the badger (49). Thus the findings on badgers and hedgehogs provided experimental evidence for mesopredator release, a situation where removal of a higher predator results in an increase in the population of a middle predator (50) and the findings on badgers and foxes gave experimental support for competitive release in sympatric carnivores (carnivores that exist in the same geographic area and thus regularly encounter one another)(51). When I first wrote about Isle Royale back in 2007, I see that I made the point that while we don’t now have the wolf, we should perhaps better appreciate the intrinsic value of foxes, the natural predator we do have and which is a mesopredator in relation to larger carnivores such as the wolf (9). I guess though that because the only manifestation of the fox that is commonly available is a cuddly, comic soft toy, then it is the usual dichotomy here of one section of Britain freely slaughtering an inconvenient wild animal, while another incorporates it into their fantasy where all wild animals are animated cartoon characters that can speak to us.

As an example of the former, I came across a recent review from last year on predation, in what is described as the mesopredator-rich landscapes of the UK, as a limiting factor for bird populations, a desk study of the literature obviously from birdists, and which laid the finger of blame at foxes as well as crows (53). The paper indicated that predator management aimed simultaneously at foxes and crows was more likely to result in stable or increasing bird populations of gamebirds (grouse, pheasants) as well as the birdists favoured waders, such as avocet, plover, curlew, lapwing and sandpiper. This is the ever-downward spiral of destruction from using predator control in nature conservation. As I have explained, take out the top predators, as we did with the wolf, lynx and bear, plus the larger birds of prey, and you end up losing the natural restraint on middle predators, like the fox, pine martin, badger, stoat, polecat, crows and the smaller birds of prey (53). The latter then become the target of predator control from the likes especially in Britain of game keeping, but also by the conservation industry - in particular the RSPB who these authors worked for - and so by chopping away at the trophic levels, we go down and down the spiral of landscapes empty of fauna, except a few birds and lots of livestock, the latter maintaining the degradation of natural vegetation – we destroy the structure of our native trophic pyramid. But then a pre-publication version of an article for the Journal of Applied Ecology paints an interesting picture on trophic associations between gamebird releases and generalist predators. What the authors found is that there is a predominantly positive association between gamebird abundance (both reared and free-roaming) and the abundance and inter-annual population growth rates of predators (54). Furthermore, they discovered that "at the landscape scale, levels of [predator] control associated with releases generally do not overcome the positive effects of resource provision". The irony of this is that the flooding of landscapes with gamebirds like the non-natives in pheasants and Red-legged Partridges, is putting other, native species at risk from the increased numbers of predators seeking to take advantage of the increase in food availability. Further irony is that predator control is a bust, because highly mobile species with high fecundity or an abundant non-breeding population, means that removed predators are easily replaced.

With wolves now breeding in the Netherlands, wolf numbers on the rise in Belgium, and the first sighting of a wolf in Lichtenstein, then there really is a presence of wolves in every country in Europe – except the UK and Ireland (55-57). Moreover, the golden jackal, a mesopredator like the fox, but which is native in Southeast Europe and on into Turkey, Syria, Iraq and the Arabian Peninsula, is gradually colonising westward in Europe, into Denmark, Estonia, France, Germany, Latvia, Lithuania, Netherlands, Poland, and Switzerland (58) and with recent confirmation of a sighting in the Tyrol in Austria (59). This poses the interesting question of whether it will be accepted as a new addition to the native trophic ecology of the countries it settles in, expanding the boundaries of its natural range, or will it be regarded as an alien invader (60). It is more, though, than just an intellectual interest for me, because – like the failing population of wolves on Isle Royale and moves to overcome that, and with the knowledge that wolves are now definitely a part of the trophic structure of continental Europe - it gets to grips with what should be issues for the trophic ecology of Britain. We must get past the dichotomy of the cuddly toy image versus the slaughter of what animals that these toys represent in real life, and recognise that predation above all else – and at every level of trophic occupancy up to the highest – is the most important component of our wild nature.

Mark Fisher 13 July 2019

(1) John A. Vucetich, Professor School of Forest Resources and Environmental Science, Michigan Technological University

(2) Professor John Vucetich. Oxford Martin Visiting Fellow, Oxford Martin Programme on Natural Governance

(3) John Vucetich, Conserving biodiversity on purpose: the role of ethics in solving an interdisciplinary problem. 1705-1730pm, 20 March. Conservation Geopolitics Forum Abstracts 19th – 22nd March 2019

(4) Conserving biodiversity on purpose: the role of ethics by John Vucetich, WildCRU Conservation Geopolitics Forum Plenary Talk

(5) Leeds Animal Studies Network - An Interdisciplinary Research Network Exploring the ‘Animal’

(6) Spring Keynote 25 March 2019: Prof. John Vucetich – Restoring the Balance: Lessons from Wolves on a Wilderness Island. Leeds Animal Studies Network

(7) John Vucetich, The People, Wolves and Moose of Isle Royale

(8) About The Project: Overview, Wolves and Moose of Isle Royale

(9) Duddon valley - woodland now and into the future, Self-willed land February 2007

(10) Nature & Science, Isle Royale National Park, National Park Service

(11) Bump, J. K., Peterson, R. O., & Vucetich, J. A. (2009). Wolves modulate soil nutrient heterogeneity and foliar nitrogen by configuring the distribution of ungulate carcasses. Ecology, 90(11): 3159-3167

(12) Edwards, J. (1983). Diet shifts in moose due to predator avoidance.Oecologia,60(2), 185-189.

(13) The Population Biology of Isle Royale Wolves and Moose: An Overview, Wolves and Moose of Isle Royale

(14) Montgomery, R. A., Vucetich, J. A., Roloff, G. J., Bump, J. K., & Peterson, R. O. (2014). Where wolves kill moose: the influence of prey life history dynamics on the landscape ecology of predation. PloS one, 9(3), e91414.

(15) All About Moose, Wolves and Moose of Isle Royale

(16) Montgomery, R. A., Vucetich, J. A., Peterson, R. O., Roloff, G. J., & Millenbah, K. F. (2013). The influence of winter severity, predation and senescence on moose habitat use. Journal of Animal Ecology, 82(2), 301-309.

(17) All About Wolves, Wolves and Moose of Isle Royale

(18) About The Project: Overview, Wolves and Moose of Isle Royale

(19) Frelich, L. E., Peterson, R. O., Dovčiak, M., Reich, P. B., Vucetich, J. A., & Eisenhauer, N. (2012). Trophic cascades, invasive species and body-size hierarchies interactively modulate climate change responses of ecotonal temperate–boreal forest. Philosophical Transactions of the Royal Society B: Biological Sciences, 367(1605), 2955-2961

(20) Peterson, R. O., Vucetich, J. A., Bump, J. M., & Smith, D. W. (2014). Trophic cascades in a multicausal world: Isle Royale and Yellowstone. Annual Review of Ecology, Evolution, and Systematics, 45: 325-345

(21) Mammals on Isle Royale- Historical Context, Isle Royal National Park, National Park Service

(22) AN ACT To provide for the establishment of the Isle Royale National Park, in the State of Michigan, and for other purposes. March 3, 1931 46 Stat. 1514

(23) Vucetich, J. A., Nelson, M. P., & Peterson, R. O. (2012). Should Isle Royale wolves be reintroduced? A case study on wilderness management in a changing world. In The George Wright Forum (Vol. 29, No. 1, p. 126). George Wright Society

(24) Isle Royale Wilderness, Wilderness Connect

(25) Is Bringing New Wolves to Isle Royale National Park "Restocking the Zoo"?  Conor Mihell, Sierra, The national magazine of the Sierra Club 2 November 2018

(26) Control of animal populations, Wildlife Management in the National Parks: The Leopold Report March 4, 1963

(27) Management Policies 2006. The Guide to Managing the National Park System. National Park Service

(28) Can the ecological functions of wolves be substituted?, Self-willed land September 2015

(29) Notice of Intent To Prepare an Environmental Impact Statement and Management Plan for Moose, Wolves, and Vegetation, Isle Royale National Park, Michigan, A Notice by the National Park Service on 07/10/2015, Federal Register

(30) Moose-Wolf-Vegetation Management Plan/EIS Isle Royale National Park, Michigan Summer 2015

(31) Plan Update: Revised Scope of the EIS, Isle Royale National Park

(32) Amended Notice of Intent To Prepare an Environmental Impact Statement To Address the Presence of Wolves at Isle Royale National Park. A Notice by the National Park Service on 06/06/2016, Federal Register

(33) Isle Royale National Park Draft Environmental Impact Statement to Address the Presence of Wolves, December 2016

(34) Compiled Subject Matter Expert Questionnaires - Technical Input regarding options for bringing wolves to Isle Royale National Park 16 May 2016

(35) Meeting Notices, Environmental Impact Statement to Address the Presence of Wolves at Isle Royale National Park

(36) All Public Scoping Correspondence, Isle Royale National Park Environmental Impact Statement to Address the Presence of Wolves

(37) All Amended NOI Public Scoping Correspondence, Isle Royale National Park Environmental Impact Statement to Address the Presence of Wolves

(38) 2017-02-16 Webinar DEIS to Address the Presence of Wolves, Isle Royale NP.mp4

(39) 2017-02-21 Webinar DEIS to Address the Presence of Wolves, Isle Royale NP.mp4

(40) Final Environmental Impact Statement to Address the Presence of Wolves, Isle Royale National Park Environmental Impact Statement March 2018


(42) Isle Royale National Park and Partners Release two Wolves on the Island, Isle Royale National Park News Release September 27, 2018

(43) Two More Wolves Transported to Isle Royale, Isle Royale National Park News Release October 5, 2018

(44) Canadian Wolves Released at Isle Royale, Isle Royale National Park News Release March 4, 2019

(45) More Wolves from Canada Transported to Isle Royale, Isle Royale National Park News Release March 26, 2019

(46) Isle Royale Wolf Population Update May 29, 2019

(47) Sattler, R. L., Willoughby, J. R., & Swanson, B. J. (2017). Decline of heterozygosity in a large but isolated population: a 45-year examination of moose genetic diversity on Isle Royale. PeerJ, 5, e3584.

(48) An ecological landscape – connectivity, cores and coexistence, Self-willed land March 2019

(49) Ecological consequence of predator removal, Self-willed land July 2014

(50) Trewby ID, Young R, McDonald RA, Wilson GJ, Davison J, et al. (2014) Impacts of Removing Badgers on Localised Counts of Hedgehogs. PLoS ONE 9(4): e95477

(51) Trewby, I.D., Wilson, G.J., Delahay, R.J., Walker, N., Young, R., Davison, J., Cheeseman, C., Robertson, P.A., Gorman, M.L. and McDonald, R.A., (2007) Experimental evidence of competitive release in sympatric carnivores. Biology letters 4(2): 170-172

(52) Roos, S., Smart, J., Gibbons, D. W., & Wilson, J. D. (2018). A review of predation as a limiting factor for bird populations in mesopredator-rich landscapes: a case study of the UK. Biological Reviews, 93(4): 1915-1937

(53) The continuing destruction of our native trophic pyramid, Self-willed land February 2018

(54) Pringle, H., Wilson, M.,Calladine, J. and Siriwardena, G (2019) Associations between gamebird releases and generalist predators. Journal of Applied Ecology 1–12

(55) The return of the wolf: Wild cubs born in the Netherlands, Mike Corder, JUNE 20, 2019

(56) Wolves on the rise in Belgium, Jules Johnston, The Brussels Times 21 March 2019

(57) Wolf in Liechtenstein gesichtet, Liechtensteiner Vaterland Samstag, 13. Juli 2019;art102,365586

(58) Hoffmann, M., Arnold, J., Duckworth, J.W., Jhala, Y., Kamler, J.F. & Krofel, M. 2018. Canis aureus. The IUCN Red List of Threatened Species 2018

(59) Erstmals Goldschakal in Tirol nachgewiesen, 03.06.2019

(60) Trouwborst, A., Krofel, M., & Linnell, J. D. (2015). Legal implications of range expansions in a terrestrial carnivore: the case of the golden jackal (Canis aureus) in Europe. Biodiversity and Conservation, 24(10): 2593-2610