Last month, a petition circulated after Countryfile host Chris Packham voiced ‘controversial’ opinions against the hunting and killing of so-called pest animals. Packham’s non-profit company Wild Justice takes legal cases against public bodies on behalf of wildlife and recently lobbied against the killing of predatory birds in the UK, such as jays, woodpigeons and crows. Their case that these licenced shootings were neither lawful nor scientifically robust was successful, leading the government’s conservation watchdog to revoke the licences that permit farmers to kill 16 species of birds. Following this action, a petition calling for Packham’s immediate dismissal by the BBC was signed by over 73,000 people and the TV host returned home to find dead crows hanging from his gate posts. That’s a pretty strong statement of dissent.
Why is this issue so contentious? Well, farmers claim that letting jays and crows thrive is unacceptable because these large birds not only damage crops but have been known to attack livestock and prey on other ‘more attractive’ wildlife, like songbirds. Public fear of these ‘savage’ birds has been fuelled by tabloids like the Daily Mail who publish pictures of bloodied lamb corpses mauled by crows or sheep with their eyes pecked out. One petitioner commented: “[Packham’s] biased opinions and hatred of countryside management are damaging our country.”
Despite seeing a distressing case firsthand, in which birds pecked out the eyes and udders of live sheep during lambing, a farmer friend of mine expressed her frustration with this attitude on social media. She explains,
“As a farmer, I am fully aware that predators and scavengers come into conflict with livestock…so, we are meant to just shoot anything we come into conflict with? Can those who hunt and shoot for ‘pest control’ honestly say that they are doing it because they have read the most recent evidence about (a) the efficacy of what they are doing and (b) the so-called increases in pest species numbers that need ‘controlling’? Are they really are responding to this evidence? Or do they primarily enjoy hunting and killing an animal and need to find a reason to justify that warped feeling to themselves?”
I wrote an earlier blog about those who use wildlife management as an excuse for sport hunting and I won’t give those sad individuals any further time here. But when it comes from a place of genuine concern for protecting vulnerable animals, countryside management is a complex issue. To Packham and his supporters, it’s insane for a statutory body with responsibility for wildlife protection to operate a licensing scheme that destroys millions of birds each year. But to others, the welfare of livestock and those that benefit from their production (including, arguably, the consumer who demands ever cheaper meat and milk) not every animal is created equal nor deserving of protection. This debate uses similar arguments to those that justify the destruction of invasive or pest species to conserve more ‘valuable’ types of animal. The BBC recently published an essay by Mark Kinver which argues that conservation “should concentrate on species or habitats rather than individual animals”. By that reasoning, it’s okay to mass-cull invasive or pest animals if that’s necessary to protect an endangered or native species. Indeed, in America the USDA’s Wildlife Services (APHIS) kill roughly 2.7 million wild animals from over three hundred different species a year, mostly ‘pest’ animals.
The key word here is ‘necessary’: Packham’s opponents argue that killing pest birds is the only way to effectively protect livestock. Of course, livestock are hardly endangered and, as Wild Justice points out, there’s a notable lack of scientific evidence supporting the necessity of killing pests to protect either livestock or other birds. The government blog Natural England states that to be granted a licence to kill a pest species, the applicant must show that “all other avenues have been explored”. They supposedly have to demonstrate that
a) actual damage or a problem is occurring
b) the species is actually causing the damage or problem, and
c) other reasonable and practical non-lethal alternatives have been considered and tried (such as scaring, trapping or proofing).
However, take this licence to kill carrion crows in the UK: users don’t need to register to use the licence and are “advised to keep a record of problems and the use of nonlethal methods, but do not need to submit records to Natural England.” The fact that millions of birds were being killed every year under the revoked licenses GL04, GL05 and GL06 (see Table 1 below) suggested to Wild Justice that all this killing cannot possibly have been legal according to the terms above. After all, if every farmer granted a licence to kill predatory birds in the last 40 years (170,000 birds in the past five years, according to The Guardian) had provided solid proof of the damage done to their livestock and the failure of alternative methods of control, why – as I’ll explore below – is there so pitifully little published evidence of either? Are farmers really exploring all practical non-lethal alternatives? Call me cynical, but it doesn’t seem very likely.
Furthermore, unlike with debates around ‘conservation management’, the ethical argument for culling crows and jays is on very shaky ground. It’s the farmers and their livestock that are the ‘invasive’ species in this case, having taken over the wild birds’ habitats and displaced both them and their natural prey. This isn’t an argument about maintaining ecosystems, it’s about human-wildlife conflict: protecting domestic animals over wild ones, or – more cynically – about protecting the economies of farming. Whether the motivation is genuine care for livestock or whether it’s simply about loss of profits, the assumption is that the lives of sheep and other farmed animals (as well as songbirds) are more important than the lives of crows and other ‘dangerous’ birds. Of course, it’s easy to reduce the problem of wildlife management to an ideological debate. If you take a deontological ethical view, the life of the individual animal – regardless of its ‘invasive’ or ‘pest’ label – has immediate value and should be protected, no matter the long-term repercussions. It’s not okay to shoot a crow even if it might go on to kill one of your lambs. A utilitarian, on the other hand, would argue that destruction of one group of animals is ethical if that saves more lives than it destroys – and farmers might argue that protecting livestock means protecting human food sources and thus people too.
But there are practical aspects at play too. Does culling or hunting pest species actually work? It’s all very well to say that killing x number of badgers is justified to save a greater number of cows from possible death by TB (not true – over four years, around 85,000 badgers will be culled to prevent the slaughter of about 17,750 cattle over nine years, which equates to about five badgers to every cow saved from early slaughter (McCulloch and Reiss, 2017a)). But what if killing badgers only has a marginal impact on bovine TB anyway? While proactive culling of badgers was found to reduce the incidence of TB in cattle in the culling area by 19 percent, it increased the disease by 29 percent in the area outside (McCulloch and Reiss, 2017b). In 2012 Patrick Bateson, President of the Zoological Society of London, published an open letter in the Observer signed by 30 eminent scientists, urging the government to reconsider the culling of badgers because “the complexities of TB transmission mean that licensed culling risks increasing cattle TB rather than reducing it” (Bateson et al., 2012).
So returning to our current example, are corvids really as big a threat to the survival of songbirds as we’re being told, or are they another ‘badger’? A 1998 paper on songbird decline in rural Britain concluded that not only have previous studies have failed to find links between the decline of breeding songbirds and mortality from avian predators, but their large-scale, long-term data indicated the same: songbird populations were unaffected by the presence of pest birds like sparrowhawks (Thomson et al, 1998). Twelve years later, the biggest ever analysis of songbirds and their predators concluded that for the majority of the songbird species examined, there was no evidence that increases in common avian predators are associated with large-scale population declines (Newson et al, 2010). Packham’s website goes through each species of predatory bird and shows that, except for the carrion crow, there is no evidence that these animals are causing declines in population levels of other species. The chief prey of carrion crows are actually foxes, not songbirds, who are “not seriously affected” by carrion crows. Madden et al (2015) reviewed 42 studies on the impacts of crows, ravens and magpies on prey bird productivity and abundance, and found no negative influence of corvids on either in 81 percent of cases. Last year, Roos et al (2018) concluded that despite high and increasing densities of predators, there is little evidence that predation limits populations of pigeons, woodpeckers and songbirds.
Is there more evidence for the efficacy of killing these predators to improve populations of songbirds or indeed in protecting livestock? A little. A 2006 paper from Spain suggests that raven populations learn lamb predation from a small number of individuals, supporting (speculative) arguments that shooting a few predators could lead to reduced numbers of deaths in the long term (Ruiz-Olmo et al., 2006). Looking at 83 predator removal studies from six continents, Smith et al conclude that “current evidence indicates that predator removal is an effective strategy for the conservation of vulnerable bird populations” (2010). In 2010 Stoate and Szczur conducted a six-year study on a Leicestershire farm that concluded that for “some species” of songbird, nest success was inversely related to abundance of breeding corvids and game management helped increase the number of songbirds. Four years later, White et al analysed 11 years of nest data from six songbird species on three farms that used different game management regimes. They also detected a positive effect of systematic predator reduction on five of these species, although they qualify “the extent to which predator reduction might influence populations may depend on mechanisms such as re‐nesting compensation and overwinter mortality” (2014).
In the same year, Marzluff and Neatherlin note in their article on corvid response to human settlements that “The process of corvid responses and their actual effects on other species is only vaguely understood” (2014). Their American study found that while corvids accounted for 32.5 percent of the predation events on 837 artificial seabird nests, removing large corvids “may do little to reduce overall rates of nest predation because of the diverse predator assemblage.” Interestingly, Bodey et al (2009) consider that “removal of larger ‘superior’ competitors often releases the ‘inferior’ ones and can precipitate trophic cascades”. Their study indicates that culling hooded crows appears to release a larger and more destructive competitor, the common raven. Roos et al (2018) point out that while lethal control can protect vulnerable species in the short term, these techniques are costly and time‐consuming. Instead, they advocate that “future research should identify land‐use practices and landscape configurations that would reduce predator numbers and predation rates.”
If it is decided, rightly or wrongly, that mass execution of the predatory species is the only possible measure, this should surely be actioned in the kindest way possible. Bekoff points out the inadequacy of Kinver’s statement in his essay that “cruelty should be minimised”. Really? Why does there need to be any cruelty at all? Sadly, wildlife management is often far from humane, especially when we consider that other non-targeted animals can suffer too. Take New Zealand’s widespread use of the lethal poison 1080 to control ‘pests’, which causes a horrific death for any animal that accidentally ingests it. Hunting pest birds in the UK is hardly cruelty-free either: injured, uncollected birds can die slowly and painfully and a targeted bird who manages to escape undergoes enormous stress. Hunting disturbance can cause temporary disruption of normal activities, alter their diurnal rhythms and disrupt pair-bonds. Licensed pest control with a marksman is arguably more humane, but how ‘humane’ can it ever be to take the life of an healthy animal who doesn’t want to die?
Ideally, there should be a way to protect the lives of all the animals involved. So does ‘compassionate conservation’, the counter argument to conservation culling, have the answer? According to American animal ethologist and animal ethics writer Marc Bekoff, this growing movement has four key tenants: First Do No harm, Individuals Matter, Value All Wildlife, and Peaceful Coexistence. There have been many examples of successful compassionate wildlife management which follow these pillars, not just in the western world. The Maasai Kenyan teenager Richard Turere, for instance, inspired Kenyans to use lights to scare off lions from villages and livestock instead of killing them, a method now being trialled in India for tigers. Rather than jumping to mass destruction as a solution, compassionate conservationists first explore the possibility of relocation or alternative ways for species to co-exist. One example of ‘justified culling’ given by Kinver is the destruction of hundreds of thousands of cats that kill millions of birds. But why not introduce a neutering programme that reduces the cat populations without killing anyone? If there’s a non-lethal alternative, the ‘justification’ for the death sentence becomes much weaker. Marzluff and Neatherlin found that reducing “anthropogenic food in the landscape” (i.e., removing human food waste and protecting livestock) might be more effective in discouraging avian predators than culling (2014). Similarly, McCulloch and Reiss concluded that in the case of bovine TB, non-culling approaches like badger vaccination resulted in greater benefits to humans and livestock compared to lethal management of badgers (2017b).
The 2010 Smith study states that, despite evidence to support the efficacy of predator removal, “the ethical and practical problems associated with predator removal may lead managers to favor alternative, nonlethal solutions”. If alternative solutions exist to culling corvids, such as relocating them or adding extra protection for the threatened species, surely farmers have a moral as well as a legal duty to reject destruction as the first option. A recent study by Liordos and Baltzi suggests that the public agree: 630 adults were asked to rate their acceptance of three management methods, i.e., do nothing, non-lethal control, and lethal control, in the context of five different human–wildlife conflict scenarios. The first was corvids damaging crops. While members of the general public agreed that doing nothing was unacceptable and non-lethal control acceptable, they didn’t accept lethal control in any scenario. Farmers, however, accepted lethal methods for the corvids (2017).
This is not to suggest that all farmers are trigger-happy crow murderers: many, like my friend, are keen to research new and innovative methods to help change farming practices so they don’t come into so much conflict with wildlife. That might mean keeping feed and grain stored in rat-proof bins or sheds, using other deterrents for corvids on arable fields, or having a shepherd with the flock. The government provides a list of alternatives to culling here, including visual deterrents, auditory scaring, human disturbance and shooting to scare (described as “highly effective”), restricting access to food sources, modification of loafing and/or roosting areas, habitat management and public education. Not all of these methods work for every farmer and it’s unlikely that many are as effective as simply shooting the pests. Research published last year suggested that relocating or disturbing ravens failed to disperse them away from livestock (Marchand et al, 2018) and only a few effective management experiments involving corvids and livestock have been reported in the literature.
Regardless, when we acknowledge that it is almost always human activity that placed these birds in the pest category in the first place, perhaps ‘somewhat effective’ is a reasonable compromise. The massive release of non-native gamebirds for hunting has provided carrion crows with more prey, inflating their populations in the UK countryside. Hunting also kills other native predators like Goshawks, meaning the carrion crows are not vulnerable to predators themselves. Yet at the same time, farming has ‘cleaned up’ the countryside: it’s not permitted to leave carcasses of dead animals in fields, so these birds have no carrion to feed on. We’ve inadvertently helped grow these populations of ‘dangerous’ birds, while at the same time depriving them of their natural food source. Can we blame them for going after live animals instead? But then again, if we’re responsible for increasing their populations in the first place, do we also have a responsibility to lethally control or ‘manage’ them, essentially ‘correcting’ our earlier mistake?
Either way, the ‘managed’ animal has no agency in this situation. A crow or jay, or even a rat, raccoon or possum doesn’t know he’s a pest, he’s just trying to survive as best he can in a world where his natural habitat has been occupied by humans and his natural prey removed. As Thirgood et al point out, “Human persecution has greatly restricted the range and abundance of most [birds of prey] species in Britain” (2001). Do we really need to keep persecuting these wild birds? If there’s an option to reduce – if not prevent – livestock predation without killing these displaced animals then, surely, as the invaders in this situation, we need to take it.
References
Bateson, P., Begon, M., Blackburn, T., Bourne, J., Sutherland, W., Burke, T., et al. (2012). Culling badgers could increase the problem of TB in cattle: Badger culling risks becoming a costly distraction from nationwide TB control. The Observer.
Bodey, T. W., McDonald, R. A., & Bearhop, S. (2009). Mesopredators constrain a top predator: competitive release of ravens after culling crows. Biology Letters, 5(5), 617-620.
Liordos, V., Kontsiotis, V. J., Georgari, M., Baltzi, K., & Baltzi, I. (2017). Public acceptance of management methods under different human–wildlife conflict scenarios. Science of the Total Environment, 579, 685-693.
Madden, C. F., Arroyo, B., & Amar, A. (2015). A review of the impacts of corvids on bird productivity and abundance. Ibis, 157(1), 1-16.
Marchand, P., Loretto, M. C., Henry, P. Y., Duriez, O., Jiguet, F., Bugnyar, T., & Itty, C. (2018). Relocations and one-time disturbance fail to sustainably disperse non-breeding common ravens Corvus corax due to homing behaviour and extensive home ranges. European Journal of Wildlife Research, 64(5), 57.
Marzluff, J. M., & Neatherlin, E. (2006). Corvid response to human settlements and campgrounds: causes, consequences, and challenges for conservation. Biological Conservation, 130(2), 301-314.
McCulloch, S. P., & Reiss, M. J. (2017). Bovine tuberculosis and badger culling in England: A utilitarian analysis of policy options. Journal of Agricultural and Environmental Ethics, 30(4), 511-533.
Newson, S. E., Rexstad, E. A., Baillie, S. R., Buckland, S. T., & Aebischer, N. J. (2010). Population change of avian predators and grey squirrels in England: is there evidence for an impact on avian prey populations?. Journal of Applied Ecology, 47(2), 244-252.
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.
Ruiz-Olmo J, Dalmau Gafas Q, Bosch Ricart J, Masoller Arias J, Cárdenas Cobos G (2006) Daños del cuervo al ganado ovino en cataluña. dimensiones del problema y criterios de gestión. Quercus (246):18–24
Smith, R. K., Pullin, A. S., Stewart, G. B., & Sutherland, W. J. (2010). Effectiveness of predator removal for enhancing bird populations. Conservation Biology, 24(3), 820-829.
Stoate, C., & Szczur, J. (2001). Could game management have a role in the conservation of farmland passerines? A case study from a Leicestershire farm. Bird Study, 48(3), 279-292.
Thirgood, S., Redpath, S., Newton, I., & Hudson, P. (2000). Raptors and red grouse: conservation conflicts and management solutions. Conservation Biology, 14(1), 95-104.
Thomson, D. L., Green, R. E., Gregory, R. D., & Baillie, S. R. (1998). The widespread declines of songbirds in rural Britain do not correlate with the spread of their avian predators. Proceedings of the Royal Society of London. Series B: Biological Sciences, 265(1410), 2057-2062.
White, P. J., Stoate, C., Szczur, J., & Norris, K. (2014). Predator reduction with habitat management can improve songbird nest success. The Journal of Wildlife Management, 78(3), 402-412.
