The evidence against the use of culling for dog and cat ‘control’

This article collates the evidence against the use of culling for dog and cat population control; different arguments will be relevant for different locations and contexts. We hope readers will identify the evidence that is most relevant for their situation and use it to develop their case for the alternative; humane management of dog and cat populations with the aim of a harmonious co-existence between people and dogs/cats.

Dog and cat populations are ubiquitous around the world; these domesticated species are part of all human communities; hence, management of their populations is common to all countries. Over the last few years, ICAM members have witnessed a reduction in the use of inhumane methods of population control globally. However, some countries still practise culling (Dalla Villa et al 2010) due to a lack of awareness of effective, humane alternatives and the mistaken belief that inhumane treatment of animals is justifiable, and the ICAM Coalition still receives requests for intervention to halt or prevent culls.

In this article, we outline the reasons and evidence for why culling should not be used for population management of dogs or cats. Culling is also known as ‘elimination’ and may be qualified by the terms ‘mass’ or ‘targeted’; however, there is no recognised threshold or criteria for when the culling of dogs or cats should be termed ‘mass’ culling. Culling is the killing of animals for reasons other than their individual welfare state; this may be simply their location or type. For example, attempting to cull all the free-roaming dogs within a particular municipality, with the aim of reducing or eliminating the population. Or as a precaution against a perceived disease risk without assessment of the individual animal’s disease status. Authorities may also cull owned cats and dogs if their owners are not keeping the animal in the manner that regulators demand, such as not fully confined by leashing/chaining/caging or not registered; in this scenario, animals are being confiscated and then culled based on the behaviour of their owners. Killing of dogs or cats for the meat trade may also be perceived as a form of culling with population control implications and will suffer the same inefficiencies described below.

Culling often involves cruel methods that cause significant suffering to animals. These methods, such as strychnine poisoning or shooting, are particularly distressing when carried out on the streets, where citizens, including children, may witness the suffering. Alternatively, authorities may collect animals from the streets and then cull within shelter facilities away from public view, where the methods used may be different but also can be inhumane, such as gassing with exhaust fumes, injections of air embolisms or toxins that cause death but without prior lack of consciousness. Culling may be indirect, as in the case of relocation of dogs or cats away from the point of capture and to an area where they are perceived to be less of a nuisance but with minimal food, water or shelter resources leading to a slow but inevitable death.

Culling differs from euthanasia, which focuses on the current and predicted welfare of an individual animal with the goal of ending suffering. Euthanasia, by definition, must always involve humane methods as outlined in article 7.7.27 of WOAH’s Chapter 7.7, Dog Population Management of the Terrestrial Animal Health Code. ICAM’s guide to developing a euthanasia policy with an animal welfare basis supports participatory and objective policy development with individual animal welfare as the priority consideration, taking note of the potential to return or rehome and the resources required to provide veterinary treatment and ongoing care to maintain good welfare (ICAM 2019). Euthanasia is part of humane population management and will be essential for all services that involve direct animal handling, including sterilisation programmes, rehoming centres and provision of veterinary services, to prevent animal suffering.

Population dynamics:

Authorities carry out culling in the belief that it will reduce or eliminate the population of free-roaming dogs or cats. However, culling has rarely achieved elimination, and these examples are limited to small islands. In all other contexts, even at the highest rates of culling, only reduction is achieved. The remaining animals have greater access to resources, and their breeding success and ability to expand or move territory increases. As a result, populations rebound to pre-culling levels (Yoak et al 2023). Rates of replacement following culling can be rapid and the resulting populations are skewed towards younger animals that are likely unvaccinated and therefore rabies-susceptible (Nunes et al 2008, Moreira et al 2004, Palmas et al 2020). That dog and cat populations replenish their numbers quickly following culls surprises some authorities, who expect their culling efforts to lead to longer lasting impacts. But even in the absence of culling, these populations are often already experiencing high natural mortality and compensatory birth rates, leading to a high turnover of populations (Morters et al 2014); hence, for many populations, culling adds relatively little additional mortality. Evolution has selected for behaviours and mechanisms that support animals to compensate for peaks in mortality, usually caused by disease or predation but here caused by culling. In comparison, a reduction in the birth rate through sterilisation can be much more impactful.
In many communities, owned populations also act as sources of free-roaming animals through abandonment, loss, and allowing pets to roam. These sources are not impacted by culling, and hence, they also continue to fuel the rebound of free-roaming populations following culls.
Western Europe and North America are known to have engaged in decades of culling free-roaming dogs and cats. This may be mistakenly perceived to have led to the low density of free-roaming animals in these regions today. However, progress in free-roaming animal management only began when emphasis moved away from culling and towards addressing the source of unwanted animals through widespread sterilisation, encouragement of responsible ownership behaviours, celebrating the value of individual animals and a commitment to lifelong ownership, controls over commercial breeding and sale and identification and registration allowing for an increase in reuniting lost animals. Progress was made in these regions despite culling and not because of it. The peak of culling, mainly in the last century, occurred before development of the more effective and humane practice of Trap/Capture, Neuter, Vaccinate, and Return (T/CNVR).

Disease (canine rabies) transmission:

The Global Alliance for Rabies Control provides a rabies specific position statement on dog culling.
Dog culling has been shown to be ineffective for control of rabies within cities such as Colombo, Sri Lanka (Hasler et al 2014), Jaipur, India (Reece and Chawla 2006), Dhaka, Bangladesh (Hossain et al 2011), Guayaquil, Ecuador (Beran and Frith 1988) and the Province of Bali, Indonesia (Putra et al 2013) and the island of Flores, Indonesia (Windiyaningsih et al. 2004).
Reducing the density of animals or people will reduce transmission of some diseases. However, this is not the case for rabies transmission within dog populations. Rabies transmission is largely independent of the density of the dog population, so even at very low densities of dogs, rabies will persist (Hampson et al 2009). Mechanisms for this persistence are unclear but are likely linked to the social nature of dogs and the fact that some dogs with rabies symptoms are able to travel reasonable distances.
Where vaccinated dogs are not clearly marked, or these marks fail over time, culling may disproportionately remove vaccinated dogs as they tend to be more accessible; a dog that was accessible for vaccination is likely to also later be accessible for culling, so culling becomes biased towards already vaccinated dogs and drives vaccination coverage down (Beran and Frith 1988). As described in the section on population dynamics, culled dogs are quickly replaced, either through breeding by the remaining dogs who give birth to susceptible puppies or by owners replacing their culled dogs by purchasing them from elsewhere, who are also likely to be unvaccinated (Morters et al 2013). Together, this reduces herd immunity and creates a dog population that is more at risk of rabies transmission.
Culling can inadvertently increase contact between dogs and lead to rabies spreading to other populations due to social perturbation of the dog populations (Beran and Frith 1988). In addition, people may proactively move their dogs to safer areas to avoid culling teams. This occurred in Bali in 2008/9 when the government attempted to control a rabies outbreak on this previously rabies-free island using culling. Owners moved their dogs from the peninsula where the culling was focused to other regions of Bali, effectively seeding rabies across the island (Putra et al 2013, Townsend et al 2013); if the authorities in Bali had adopted an evidence-based vaccination programme instead of reactionary culling, dog owners would not have felt threatened by indiscriminate cruelty and moved their dogs to safety.
The WHO’s report following expert consultation on rabies (2018; TRS 1012) has a clear stance against the use of culling for rabies control: “Mass dog vaccination has repeatedly been shown to be effective for controlling dog-mediated rabies, whereas removal of dogs does not decrease dog density or control rabies in the long run. Mass culling of dogs should therefore not be a part of a rabies control strategy: it is ineffective and may be counterproductive to vaccination programmes, particularly when they target free-roaming dogs.”

Childrens’ right to be protected from violence:

The UN Committee for the Rights of the Child has demanded that states must protect children ‘from all forms of physical and psychological violence’, including ‘violence inflicted on animals’. This includes the public culling or public removal for culling elsewhere of free-roaming dogs and cats. This is in recognition of the link between exposure to animal cruelty and human violence, especially when such cruelty is institutionalised and witnessed by children. Children are at higher risk of serious harms following exposure to violence against animals compared to adults. This is partly because children are still developing empathy and have a greater predisposition to “biophilia”, the innate connection humans have with the natural world, including animals.

Social acceptability:

Public support for culling is limited to a minority of individuals, KAP surveys exploring attitudes to free-roaming animals and options for management report very low agreement with the use of culling (Munir et al 2023, 3 unpublished KAP studies). Culling leads to public protests in some communities, particularly when humane alternatives such as mass vaccination or Trap/Catch, Neuter, Vaccinate and Return (T/CNVR) are possible. Reports of authorities culling owned and vaccinated cats and dogs are frequent and lead to further mistrust between government services and local communities.
Acceptability will be particularly low where inhumane methods of culling are used, such as strychnine and shooting; article 7.7.27 of WOAH’s Chapter 7.7 also lists many other unacceptable methods of killing dogs.
Non-lethal and effective alternatives to culling for population management and rabies control exist. Dogs and cats are sentient beings with the capacity to suffer, hence ethical arguments do not support culling as justified.
Culling of owned animals may be used as a punitive measure for an owner’s failure to comply with regulations, such as confinement, muzzling or registration/licensing. However, these demands are often beyond the reach of many current owners due to economic reasons (excessively high registration fees), incompatible housing infrastructure (traditional housing with no boundary fencing) or the animal’s intended purpose (confinement limits ability to guard or perform pest management role). Such draconian regulations will appear unjust and elitist, allowing only the wealthy to be compliant owners and leading to the culling of animals owned by those in the lowest socioeconomic strata, or abandonment to avoid non-compliance making the situation worse.

Economics of culling:

Culling may be perceived as a ‘cheap’ alternative to humane approaches such as sterilisation, however, culling involves many hidden costs causing culling programmes to become expensive and labour intensive (Herrera et al 2022, Parkes et al 2014). For example, where toxins are used to cull, there is a need to monitor and dispose of uneaten bait and the dead bodies of culled dogs and cats, to protect the public and non-target animals from encountering toxins. Staff costs can also be high, as the public is very unlikely to actively engage in culling, unlike humane approaches which often have significant volunteer support. Where animals are caught and held in shelters for a period of time before culling, there will be a high cost of kennelling and significant costs relating to high staff turnover due to the stress of continued culling.
Where legislation demands that free-roaming animals are culled, and private companies are contracted to conduct this culling, with or without a holding period, this creates the perception of free-roaming dogs and cats as a resource from which to make a living. This creates an economic incentive for their continued reproduction, rather than a motivation to reduce their numbers.
Culling only deals with the current population of free-roaming dogs or cats, addressing the symptom rather than the cause or source. This means culling must continue indefinitely. It can become a sunk cost fallacy, where the practice persists despite its ceaseless and cyclical nature. Sporadic culls are followed by an inevitable rebound of free-roaming animals and a return to the original related problems.
Benka and Boone et al (2022) found that culling cats is more expensive than sterilisation for achieving the same reduction in population numbers. In Benka and Boone’s study, culling involved removing cats from the streets and killing them in shelters.
One reason for this higher cost is that more individual animals need to be culled than need to be sterilised for the same population outcome. After culling, all the remaining animals are left with the capacity to breed and face less competition over resources, leading to a population rebound. In contrast, sterilised populations do not suddenly find themselves without competition for resources and, when T/CNVR has been applied intensively, very few animals can breed so the capacity for population rebound is blunted. This means fewer new unsterilized puppies/kittens or immigrated animals are available for sterilisation when management is next applied. As a result, the number of animals needing sterilisation decreases each year, whereas culling requires a similar number of animals killed year after year.

Humane alternatives to culling:

The argument against the use of culling is further strengthened by the existence of proven humane and effective alternatives for free-roaming dog and cat population management.
- Rehoming centres where free-roaming animals can be reunited with their owners or rehomed with new owners can be used. However, their success is dependent on a widespread practice of rehoming and reuniting and significant funding to ensure good welfare. Rehoming centres should be used for temporary housing until reuniting or rehoming is achieved. Sanctuaries with no intention to rehome, or shelters with predictably very low rehoming rates, are ineffective for population management, as like culling, they only address the symptom of the current free-roaming population and not the source. They quickly fill to capacity as new dogs and cats continue to appear on the street due to birth, migration or abandonment. The welfare of dogs and cats in such facilities can also be very poor and financial costs extremely high, including large capital expenditure, high ongoing financial costs and challenges with staff management and training.
- T/CNVR can be more affordable and appropriate for street adapted or unsocialized animals, especially when rehoming practices are minimal. This approach allows animals to be managed in situ the streets meaning their ongoing care is not solely in the hands of a sanctuary, rather they are returned to the care of the community that has supported them to this point. When compared to culling, T/CNVR can lead to similar reductions in numbers as culling but this depression in numbers is more persistent as the remaining animals have limited capacity to breed and replenish their numbers (Yoak et al 2023).
Both rehoming and T/CNVR are one part of a comprehensive population management system that must also include preventative services to stem sources of future free-roaming dogs and cats:
- Promoting responsible animal ownership behaviours such as sterilisation, vaccination and identification with registration of dogs and cats is achieved through education, regulation and service (principally veterinary) provisioning. Expectations of owner behaviours need to be realistic; draconian measures that owners cannot feasibly achieve will lead to animal abandonment, culling and public disobedience. Reasonable expectations with clear benefits to animals, owners and communities will instead be welcomed by owners when paired with accessible services, with uptake of these behaviours benefiting from the development of social ‘norms’ or expectations. Policies with implications for owner behaviour should be assessed for their likely impact before implementation to ensure they are reasonable and will benefit from the support of a critical mass of owners.
- Control of commercial dog and cat breeding and selling needs to prevent the production of unhealthy and unsocialised animals at high risk of abandonment and ensure that acquisition is a thoughtful process with life-long commitment. Ideally also encouraging rehoming.
Comprehensive guidance on dog and cat population management is available from ICAM’s website.

In summary, the case against culling is strong and humane alternatives exist. As a result, culling as an approach to dog and cat population management is no longer pursued in most countries. Until all countries have ended these practices, ICAM will continue to support the wider dog and cat population management community to advocate and develop humane and effective alternatives.

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About International Companion Animal Management (ICAM) Coalition

ICAM supports the development and use of humane and effective companion animal population management worldwide. The coalition was formed in 2006 as a forum for discussion on global dog and cat management issues.

Our key goals are to: