Article

Cat Demographics & Impact on Wildlife in the USA, the UK, Australia and New Zealand: Facts and Values

Authors:
  • WellBeing International
  • Four Paws International
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Abstract

The estimated populations of domestic cats in the USA, whether pets, stray or feral, vary widely and have changed significantly over the past forty to fifty years. Accurate estimates of these populations are necessary to determine appropriate policy responses to calls to control domestic cats and to determine the impact of domestic cats on wildlife populations. Domestic cat predation on wild animals is being hotly debated in Australia, New Zealand and the USA (but much less so in the UK). The paper explores some of the different policy approaches being promoted in each country and examines the status of cats in each country. For example, although there is strong movement to control cat predation in New Zealand, the country also has the highest relative (to humans) population of pet cats in the world, despite the vulnerability of native animals to predation by introduced carnivores.

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... as an important problem by most conservation groups and authorities, with the exception of managing domestic-wildcat hybridisation in Scotland (Rowan et al. 2019). It is perhaps unsurprising that cats are less controversial in the UK than elsewhere; unlike places like Aotearoa/New Zealand, feline predators (namely wildcats and lynx) are native to Britain, and domestic cats have been present since at least the Iron Age (Kitchener and O'Connor 2010). ...
... Furthermore, disagreements may arise about how best to prevent hybridisation between wildcats and feral domestic cats, echoing arguments about TNR efficacy for controlling outdoor cat populations in the USA (Wald and Peterson 2020). A gamekeeper argued that killing feral cats is more effective than the trap-neutervaccinate-release approach taken by the wildcat conservation project led by government agency Scottish Natural Heritage (SNH) (Rowan et al. 2019): an approach adopted because "it would have been a bit more difficult" in terms of public image to carry out lethal control, according to one individual involved. This divergence of views has led to tensions, with some gamekeepers reluctant to let conservationists onto their land to trap and re-release feral cats (I14). ...
... Furthermore, cat advocates may express concern about the negative welfare impacts of anti-predation measures like keeping cats indoors. Representatives from two of the three animal welfare/protection groups I contacted indicated that they do not advocate for keeping cats indoors, on the grounds that they view outdoor access as important for cat welfare in most cases (see also Rowan et al., 2019). There are therefore likely to be few NGOs interested in advocating for the welfare of wild animals at the expense of cats. ...
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This article examines why cat predation is not on the agenda for most UK-focused conservation NGOs. Drawing on interviews and an analysis of scientific literatures and social media, I show that there are genuine epistemic uncertainties about whether cat predation presents a widespread conservation problem in the UK. This means that characterising NGOs' position as science denialism is unjustified. However, I argue that NGOs may wish to avoid looking into the issue too closely, due to a belief that the matter is irresolvable: a view founded on assumptions about what the British public thinks, and what politicians think the public thinks. Finally, I show that while there is little fighting about cats between conservationists and cat advocates, cats are readily 'grafted' onto existing disagreements about gamekeeping and predator control. I conclude that the small British cat debate is unlikely to get any bigger in future, and that the case illustrates the importance of bringing together social science literatures on NGO politics, science and technology, and human-animal relationships when seeking to understand 'issue creation' by conservation NGOs. Furthermore, it highlights the need to attend to local cultures, practices, and ecologies rather than assuming that issues will translate across contexts.
... That is why it is useful in this collection of papers not to restrict our interest in human-cat interactions and the behaviors they yield to the domesticated cats eating preprepared cat food from a can or a dry food package and leaving their litter in an absorbent clay cat box. The cats that do live outside their "homes, " beyond the bounds of domesticity as we put it, and sometimes in large numbers (11,12), raise questions about human interests in and concerns about cats that merit attention even in a set of papers primarily focused on those human-cat interactions that occur within the bounds of domesticity. ...
... In important ways our interest in cats and their behavior, as well as our interest in whether and why and how we want to regulate that behavior, is conditioned by the context in which cats are found. Some of them lead lives that are completely wild and free ranging and some are completely tame and confined (12). Context is related to regulation. ...
... The way this precept works in practice for the cats can vary considerably, however, from one country to another and from one locality to another, depending on how firmly the moral precept against killing impounded cats is locally held. In the aggregate and across many urban and suburban jurisdictions, it is still the case that locally managed animal control programs euthanize large numbers of cats every year, although this now occurs less frequently than used to be the case (12). ...
Article
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Although human interactions with cats are often even typically analyzed in the context of domesticity, with a focus on what sorts of interactions might make both people and cats “happy at home,” a large number of cats in the world live, for one reason or another, beyond the bounds of domesticity. Human interactions with these more or less free-living cats raise deeply controversial questions about how both the cats and the people they interact with should be sensibly managed, and about the moral imperatives that ought to guide the management of their interactions through the laws and public policies regulating both human interactions with pets and with wildlife. We review the geography of human interactions with cats living beyond the bounds of domesticity. We acknowledge the contributions made to ideas about how to manage cats by the animal protection movement. We review the tensions that have emerged over time between advocates for the eradication of free-living cats, because of the impacts they have on native wildlife species, and those who have imagined alternatives to eradication, most notably one or another variant of trap-neuter-return (TNR). The conflict over how best to deal with cats living beyond the bounds of domesticity and their wildlife impacts raises the prospect of stalemate, and we canvass and critique possibilities for moving beyond that stalemate.
... The domestication of the cat, Felis catus L. (Carnivora: Felidae), started more than 9000 years ago through a commensal pathway based on the ability of cats to control rodent pests in human settlements (Driscoll et al., 2007;Engels, 1999;Zeder, 2012). Cats can live as feral animals independently from human provisioning in some locations, but they live mostly in close association with humans (Crowley et al., 2020;Rowan et al., 2019). Although the cat's domestication was associated to its ability to control rodents, cats are opportunistic generalist predators, predating on small and medium-sized animals (Fitzgerald & Turner, 2000;Krauze-Gryz et al., 2017;Kutt, 2012). ...
... Some prey species have also been shown to develop antipredator responses after novel exposure to cats (Carthey & Banks, 2016;West et al., 2018). Moreover, considering that cats are mostly and at their densest in close proximity to human settlements (Campos et al., 2007;Crowley et al., 2020;Gehrt et al., 2013;Møller & Ib añez-Álamo, 2012;Rowan et al., 2019;Stracey, 2011), the impact of cats is often limited. Around human settlements cats have mainly local effects on biodiversity (Turner, 2021b). ...
Article
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Abstract Cats, Felis catus L. (Carnivora: Felidae), were domesticated because of their role in rodent control around human settlements. Free‐roaming cats (henceforth, referred to as “cats”) can predate on a wide variety of small‐ to medium‐sized animals and affect biodiversity. The impact of cats on biodiversity varies from country to country, region to region, and habitat to habitat. Depending on the location and context, the overall impact of cats on biodiversity can be negative, neutral, or positive. Management of cats should take into account the complex interactions that occur between cats, rodents, and the species they prey upon.
... Beyond basic agreement that reducing the number of FRCs is desirable, there is often a lack of consensus about how to best accomplish this goal. 12 This has led to highprofile debates and legal battles about FRC management in municipalities (eg, Los Angeles, CA) and even countries (eg, Australia). [12][13][14][15][16][17] Typically, animal welfare organizations favor using non-lethal (also termed 'humane') methods that rely on the surgical sterilization of cats, such as trap-neuterreturn (TNR), and cite projects where this approach has been successful. ...
... 12 This has led to highprofile debates and legal battles about FRC management in municipalities (eg, Los Angeles, CA) and even countries (eg, Australia). [12][13][14][15][16][17] Typically, animal welfare organizations favor using non-lethal (also termed 'humane') methods that rely on the surgical sterilization of cats, such as trap-neuterreturn (TNR), and cite projects where this approach has been successful. 6,[18][19][20][21][22] In contrast, many wildlife conservation organizations are skeptical about the effectiveness of TNR in reducing FRC numbers. ...
Article
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Objectives: This study used computer simulation modeling to estimate and compare costs of different free-roaming cat (FRC) management options (lethal and non-lethal removal, trap-neuter-return, combinations of these options and no action) and their ability to reduce FRC population abundance in open demographic settings. The findings provide a resource for selecting management approaches that are well matched for specific communities, goals and timelines, and they represent use of best available science to address FRC issues. Methods: Multiple FRC management approaches were simulated at varying intensities using a stochastic individual-based model in the software package Vortex. Itemized costs were obtained from published literature and expert feedback. Metrics generated to evaluate and compare management scenarios included final population size, total cost and a cost efficiency index, which was the ratio between total cost and population size reduction. Results: Simulations suggested that cost-effective reduction of FRC numbers required sufficient management intensity, regardless of management approach, and greatly improved when cat abandonment was minimized. Removal yielded the fastest initial reduction in cat abundance, but trap-neuter-return was a viable and potentially more cost-effective approach if performed at higher intensities over a sufficient duration. Of five management scenarios that reduced the final population size by approximately 45%, the three scenarios that relied exclusively on removal were considerably more expensive than the two scenarios that relied exclusively or primarily on sterilization. Conclusions and relevance: FRCs present a challenge in many municipalities, and stakeholders representing different perspectives may promote varying and sometimes incompatible population management policies and strategies. Although scientific research is often used to identify FRC impacts, its use to identify viable, cost-effective management solutions has been inadequate. The data provided by simulating different interventions, combined with community-specific goals, priorities and ethics, provide a framework for better-informed FRC policy and management outcomes.
... 4 Limited information exists on the exact number of pet cats with outdoor access; however, between 30% and 44% of owned cats in North America are estimated to have some outdoor access. 5,6 In addition, there are an estimated 30-80 million feral cats in the USA. 6 At a minimum, it is reasonable to expect that there is a population of hundreds of thousands of feral and owned cats outdoors, mostly concentrated near urban population centers. ...
... 5,6 In addition, there are an estimated 30-80 million feral cats in the USA. 6 At a minimum, it is reasonable to expect that there is a population of hundreds of thousands of feral and owned cats outdoors, mostly concentrated near urban population centers. ...
Article
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Objectives The aim of this study was to determine the prevalence of internal parasites in feral and free-roaming owned cats in the region of Portland, Oregon, USA. Methods Fecal samples from asymptomatic cats were opportunistically collected from feral cats presented for surgical sterilization (n = 46), as well as free-roaming owned cats (n = 86) presented to primary care clinics. Fecal analysis was performed using the Baermann technique, centrifugal flotation, fluorescent auramine and fluorescent antibody for Giardia species. Results Lungworm infection was identified in 24.2% of owned cats and 17.2% of feral cats. At least 11 unique parasite species were identified in this study. Taenia species and Toxocara cati were identified in higher proportions in feral cats, whereas Giardia species were significantly higher in owned cats. Conclusions and relevance The prevalence of lungworm was higher than has been previously documented in other areas of the USA. In addition, feral cats were infected with a higher percentage of Toxocara species and Taenia but a significantly lower percentage of Giardia species.
... 38,50,51 And resource-rich urban areas are where an estimated 75% of free-roaming cats in the US are found. 52 In addition, feeding cats presumed to be stray is a common activity (10-26%, depending on the survey) across the US, 4,53-55 making enforcement of feeding bans a challenge. n It is worth noting, too, the studies showing that regularly fed free-roaming cats are less likely to kill wildlife than their unfed conspecifics. ...
... Numerous locations where free-living Green Iguanas have been reported in Hong Kong to date have been heavily developed areas, which is indicative of a high proportion of individuals originating from escaped or released pets (Mo and Mo 2022). In such environments, the impacts on wildlife from free-roaming and stray dogs (Young et al. 2011;Hughes and Macdonald 2013;Home et al. 2018) and cats (Loss et al. 2013;Rowan et al. 2019) are well-documented. Both are plentiful in Hong Kong (Dahmer 2002;Chemonges-Nielsen 2003;Woo et al. 2012) and are likely to provide an important source of predation. ...
Article
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Biological control is the management of non-native species through the use of their natural enemies. The Green Iguana (Iguana iguana), a large lizard of the Neotropics, has established populations in extralimital countries. There has been an increasing recent pattern of reports of free-living Green Iguanas in Hong Kong, which was the trigger of this desktop assessment of native Hong Kong fauna that may prey upon escaped or released iguanas. A literature review found documented predators of Green Iguanas from 12 vertebrate orders. There were two mammalian orders (Carnivora, Primates), eight avian orders (Cuculiformes, Pelecaniformes, Accipitriformes, Cathartiformes, Falconiformes, Strigiformes, Piciformes, Passeriformes), and two reptilian orders (Squamata, Crocodylia), which are all presently represented in Hong Kong with the exception of the orders Cathartiformes and Crocodylia. Based on knowledge of other taxa documented to prey upon lizards represented in Hong Kong, we suggested additional prospective predators of Green Iguanas from one further mammalian order (Artiodactyla) and one further avian order (Ciconiiformes). Since avian species generally have a greater representation in settled areas, along with stray domestic dogs and cats, we expect these species to be the potential predators most likely to take iguanas when they are first released or escaped.
... Although there is no consensus on the exact numbers, some researchers have estimated that owned and unowned (feral and stray) free-roaming domestic cats kill 61 million birds and 53 million reptiles in Australia annually [23,24]. Despite the possibility that cat numbers and therefore predation may be over-estimated [25], the threat of cat predation on wildlife has led to them being listed amongst 100 of the world's worst invasive Animals 2023, 13, 1711 3 of 21 species [9]. The extent and significance of free-roaming cats and their impact on wildlife destruction are an ongoing debate [4]. ...
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Free-roaming cats pose a risk to their own health and welfare, as well as to the health and welfare of wildlife and humans. This study aimed to monitor and quantify area-specific free-roaming cat movement. Two local government areas (LGAs) in Greater Sydney were included, Campbelltown (CT) and the Blue Mountains (BM). Motion-capture cameras were installed on 100 volunteer properties (50 per LGA) to indirectly capture animal movements over two months. Transect drives were completed eight times (four per LGA) to directly observe roaming cats in residential areas. The cameras and transects both identified higher free-roaming cat numbers in CT (density of 0.31 cats per ha, resulting in an estimated abundance of 361 cats in the 1604 ha of residential area) than the BM (density of 0.21 cats per ha, resulting in an estimated abundance of 3365 cats in the 10,000 ha of residential area). More wildlife events were captured in the BM (total = 5580) than CT (total = 2697). However, there was no significant difference between CT and the BM for cat events (p = 0.11) or wildlife events (p = 0.32) observed via the cameras. Temporally, cats were observed via the cameras throughout the entire day with peaks at 9:30 am and 8:00 pm in the BM, and 7:00 am and 12:00 pm in CT. Overlaps in activity times were recorded for free-roaming cats with bandicoots (BM), possums (BM), and small mammals (BM and CT). This study demonstrates that camera monitoring on private property and transect drives are useful methods to quantify free-roaming cat abundance to inform cat management interventions.
... For instance, Loss et al.'s (2012) claim that cat predation in North America kills tens of billions of birds and other animals is based on poor "guesstimations." Relatedly, the idea that cats equally threaten animals across urban, rural, and wild landscapes fails to account for the concentration of cats around human settlements, questions of seasonal variations, differences between individual cats' predaciousness, or whether cat predation adds to or substitutes for other causes of wildlife mortality Matthews, 2013;Rowan et al., 2019;Wolf, 2016). ...
Article
The relationship between people, outdoor cats, and wildlife is the subject of fraught debate. Some conservationists claim cats are harbingers of chaos – akin to a zombie apocalypse threatening biodiversity and public health. The empirical evidence and scientific reasoning do not bear this out. Cats may or may not be a problem for biodiversity depending on diverse ecological and social contexts. Indeed, while all animals can be vectors or victims of zoonotic disease, cats are not a significant threat to public health. While most of the debate is focused on dueling claims about the science, that is not the primary source of the dispute. Instead, moral disputes drive the debate, and managing the relationship between people, cats, and wildlife is a wicked problem rooted in differing ethical values and worldviews. While wicked problems have no permanent or technical fix, addressing their ethical aspects is key to unlocking productive policy options.
... They might also cause a nuisance to humans, mainly by impairing sanitation (9,10). These conflicts are intensified in the urban setting, where cats form large populations, increasing human-cat interaction (12,13). ...
Article
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Significance Although popular companion animals, domestic cats pose numerous problems when free-roaming, including predation of wildlife, hazards to humans, impaired sanitation, and a decrease in their welfare. Thus, managing their populations is essential. The trap–neuter–return method (TNR; capturing, sterilizing, returning/releasing) is widely employed for managing cat populations. However, there is a lack of long-term controlled evidence for its effectiveness. We examined the outcomes of high-intensity TNR by performing a 12-y controlled field experiment. Neutering over 70% of the cats caused population decline when applied over contiguous areas. However, it was limited by a rebound increase in reproduction and survival. These findings provide a robust quantification of the limitations and the long-term effectiveness of TNR.
... That stated this is challenging if a cat supplements its diet by hunting prey. Cat access to the outdoors and the impact of their predatory behaviours on wildlife is a contemporary issue in NZ [51][52][53]. While several studies have suggested that unrestricted outdoor access improves cats' overall health and welfare [10,12,44] and that limited outdoor access can be considered a potential risk factor for obesity in cats [19,44], this needs to be balanced against "the potential negative impacts of cats on communities, other species, and ecosystem" p5 [54]. ...
Article
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One in four New Zealand cats are overweight or obese, conditions associated with poor health outcomes. As part of an online survey that was conducted from January 2019 to March 2019, NZ residents aged ≥18 years were asked demographic questions along with questions related to the body condition, breed and diet of their cat/s. From the responses, possible owner-related risk factors for developing obesity were identified. Of the respondents, 65.5% (n = 1537) owned cat/s; the owners being more likely to be female, live rurally, or live with children. Most of the respondents fed their cat/s biscuits from the supermarket (63%) and wet food (57%). Almost half (45%) fed their cat/s specialised food from a pet shop or veterinary clinic and gave them treats, with 31% of respondents feeding their cat/s raw meat. Feeding cats a variety of food types may make it difficult to estimate the appropriate amount of each needed to avoid excess caloric intake. In addition, approximately 30% of the respondents did not agree with the correct body condition statement, revealing a need for owner education. These findings highlight important areas of cat nutrition requiring future research to better inform the development of healthy weight interventions for NZ cats.
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The free-ranging cat is a significant threat to global biodiversity, yet there is a dearth of research on the fundamental biology of these non-domesticated felines within China. Between 2018 and 2022, we undertook a comprehensive study focusing on the population dynamics and reproductive biology of free-ranging cats on the Xianlin Campus of Nanjing University, which covers approximately 195 hectares. Utilizing point sampling surveys conducted over a continuous 20-day period, we generated a population accumulation curve for the cat population. Despite having pre-existing knowledge of the cats’distribution, we found that a single day of sampling yielded a discovery rate of only 51. 22%, with a confidence interval of 44. 51% to 53. 66%. This rate improved to 84. 15% (confidence interval: 81. 10% to 86. 59%) following six days of repeated sampling efforts. From 2018 to 2022, the cat population on the Xianlin Campus of Nanjing University saw a swift increase, rising from 51 individuals in 2018 to 220 by 2022. To delve into the population’s dynamics and reproductive patterns, we conducted detailed monthly surveys six times between March 2021 and March 2022. Over this period, we documented a total of 273 cats, comprising 149 adults and 124 kittens, with a near-even sex ratio. The one-year retention rate for the cats was approximately 58. 71%, with a marked difference favoring neutered cats over their unneutered counterparts in terms of survival. Regarding reproduction, while cats are capable of breeding year-round, the peak breeding season is predominantly from March to June. Among the 65 recorded litters, 84 cats survived past the six-month mark. Assuming an average litter size of 3 to 4 kittens, the survival rate of these feral cats on the campus at six months was estimated to be around 36. 92%, with a range of 32. 31% to 43. 08%. Our findings suggest that sampling efforts of low intensity may have led to an underestimation of the free-ranging cat population. Furthermore, in an environment where human care is abundant, the survival and reproductive success rates of these cats remain high, unaffected by limitations in food, shelter, or disease. This presents considerable challenges for the control and management of free-ranging cat populations.
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Management of domestic and wild animals is an integral part of conservation and is often based on how an animal is categorised. For example, feral cats are often killed, while valued companion cats and native wildcats are protected. Drawing on qualitative research and using the concept of boundary‐work, this paper examines the complex categorisation and management of cats within conservation in Britain and Aotearoa, New Zealand (NZ). We examine how, both in theory and in practice, valued companion and wildcats are distinguished from unprotected feral cats, and in‐between categories of stray and hybrid cats. We demonstrate that stakeholders draw boundaries between cat categories differently. These differences in boundary‐drawing reflect the inherent blurriness of category boundaries, practical challenges and, importantly, differences in values, in particular whether priority is placed on the life of the cat or the cat's potential victim, particularly native or game birds. This can mean that laws outlining protections for specific categories of animals have limited effect if, in practice, those encountering cats draw boundaries differently. This paper also reports on important differences between the two case studies. In NZ, even cat advocates support the humane killing of unambiguously feral cats while this is less true in Britain. Furthermore, due to the nature of the contexts, conservationists in NZ are more inclined to assume that ambiguous cats are feral whereas conservationists in Britain are more inclined to assume that they are wildcats. This paper demonstrates that values not only shape people's perceptions and treatment of animals but also how they draw boundaries between them. This finding may have important implications for understanding other controversies in conservation and animal management. Read the free Plain Language Summary for this article on the Journal blog.
Chapter
This chapter addresses ethical concerns in companion animal practice including shelter medicine, outdoor cats, overpopulation, neutering/gonadectomy, conformational disorders/brachycephaly, convenience surgeries/declawing/onychectomy, behavioral medicine, referrals, futile intervention, obesity, and access to veterinary care. Modern animal shelters provide an array of services with population control and animal welfare at the forefront. Sterilization programs have been an integral part of shelter missions to control overpopulation and stop the influx of unwanted animals into shelters. Some shelters have stopped taking in unsocialized cats and euthanizing them. Instead, these cats are now being sterilized, vaccinated, and returned to field. The dog and cat overpopulation crisis in the 1970s coincided with surgical sterilizations becoming routine in private clinics. Neutering involves the surgical removal of gonads. It is performed primarily to prevent companion animal overpopulation. Conformational disorders occur when an animal's shape and structure negatively impact its health and welfare.
Article
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Substantial societal investment is made in the management of free-roaming cats by various methods, with goals of such programs commonly including wildlife conservation, public health protection, nuisance abatement, and/or promotion of cat health and welfare. While there has been a degree of controversy over some of the tactics employed, there is widespread agreement that any method must be scientifically based and sufficiently focused, intensive and sustained in order to succeed. The vast majority of free-roaming cat management in communities takes place through local animal shelters. Throughout the 20th century and into the 21st, this consisted primarily of ad hoc admission of cats captured by members of the public, with euthanasia being the most common outcome. In North America alone, hundreds of millions of cats have been impounded and euthanized and billions of dollars invested in such programs. Given the reliance on this model to achieve important societal goals, it is surprising that there has been an almost complete lack of published research evaluating its success. Wildlife conservation and public health protection will be better served when debate about the merits and pitfalls of methods such as Trap-Neuter-Return is grounded in the context of realistically achievable alternatives. Where no perfect answer exists, an understanding of the potential strengths and shortcomings of each available strategy will support the greatest possible mitigation of harm—the best, if still imperfect, solution. Animal shelter function will also benefit by discontinuing investment in methods that are ineffective as well as potentially ethically problematic. This will allow the redirection of resources to more promising strategies for management of cats as well as investment in other important animal shelter functions. To this end, this article reviews evidence regarding the potential effectiveness of the three possible shelter-based strategies for free-roaming cat management: the traditional approach of ad hoc removal by admission to the shelter; admission to the shelter followed by sterilization and return to the location found; and leaving cats in place with or without referral to mitigation strategies or services provided by other agencies.
Conference Paper
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A major source of conflict in the management of cats arises from the fact that, in Australia and elsewhere, they are viewed simultaneously as troublesome feral pests and as valued companion animals. A further source of conflict arises from the methods that are used to manage cats. On the one hand, populations of feral cats are controlled usually by lethal methods (e.g. shooting) or by expensive exclusion fencing. On the other, management of domestic cats tends to focus on local and state government legislation that encourages owners to look after their pets responsibly. Despite the expense and controversy that attends these methods of management, they are applied patchily in most areas and there is little indication of how effective they are in achieving their objectives. We argue here that much of the conflict in cat management is due to misperceptions about what cats are and what they do, and outline a series of steps that should help to guide the management of cats in future. The steps include recognizing differences in value between owned domestic and feral cats; recognizing the impacts of cats on native fauna, communities and ecological processes; and understanding the effects of management procedures on individuals and populations of cats. We conclude by suggesting strategic means of cat management that may be acceptable to both sides of the debate about this pet/pest species.
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Misinformation (or denialism), the disingenuous assertion of information contradicting overwhelming scientific consensus, increasingly poses a challenge for invasion biology. The issue of free-ranging domestic cats (Felis catus) provides an example of this misinformation: overwhelming consensus shows that cats are invasive species that impact wildlife and human health yet free-ranging cat advocates propagate misinformation about such impacts to support policies keeping cats on the landscape. These advocates also attempt to discredit peer-reviewed scientific research on cat impacts, as exemplified by the response to a high-profile paper estimating cats annually kill billions of U.S. birds and mammals (Loss et al. in Nat Commun 4:1396, 2013). Although favorably received by scientific and invasive species management communities, an effort was launched to discredit this paper by criticizing its methods, including a report commissioned by a feral cat advocacy group and a post by a feral cat blogger. These same organizations and individuals have made similar criticisms at scientific conferences and policy roundtables. Given the realized effects of this campaign in influencing invasive species policy, we here respond to these criticisms and show they are characterized by numerous errors and misrepresentations. We conclude that the criticisms are part of the broader campaign to fabricate doubt about outdoor cat impacts and stymie policies favoring removal of cats from the landscape. Because misinformation surrounding cats is emblematic of the broader issue of misinformation and denialism, this response will not only facilitate evidence-based policy for managing cats but also stimulate research and discussion into causes and impacts of misinformation in invasion biology.
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This retrospective study of cat admissions to RSPCA Queensland shelters describes changes associated with improved outcomes ending in live release in 2016 compared to 2011. There were 13,911 cat admissions in 2011 and 13,220 in 2016, with approximately 50% in both years admitted as strays from the general public or council contracts. In contrast, owner surrenders halved from 30% to 15% of admissions. Percentages of admissions ending in euthanasia decreased from 58% to 15%. Only 5% of cat admissions were reclaimed in each of these years, but the percentage rehomed increased from 34% to 74%, of which 61% of the increase was contributed by in-shelter adoptions and 39% from non-shelter sites, predominately retail partnerships. The percentage temporarily fostered until rehoming doubled. In 2011, euthanasias were most common for medical (32% of all euthanasias), behavioral (36%) and age/shelter number (30%) reasons, whereas in 2016, 69% of euthanasias were for medical reasons. The number of young kittens euthanized decreased from 1116 in 2011 to 22 in 2016. The number of cats classified as feral and euthanized decreased from 1178 to 132, in association with increased time for assessment of behavior and increased use of behavior modification programs and foster care. We attribute the improved cat outcomes to strategies that increased adoptions and reduced euthanasia of young kittens and poorly socialized cats, including foster programs. To achieve further decreases in euthanasia, strategies to decrease intake would be highly beneficial, such as those targeted to reduce stray cat admissions.
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In August 2008, the University of New South Wales (UNSW) in Sydney, Australia, commenced a trap-neuter-return (TNR) program to manage the population of approximately 69 free-roaming unowned urban cats on its Kensington campus. The goals of the program included an ongoing audit of cats on campus, stabilization of cat numbers through TNR, and a subsequent reduction in cat numbers over time while maintaining the health of remaining campus cats. Continuation of the TNR program over nine years resulted in a current population, as of September 2017, of 15 cats, all desexed (78% reduction). Regular monitoring of the cats through a daily feeding program identified a further 34 cats that immigrated on to campus since initiation of the program; these comprised 28 adult cats (16 unsocialized, 12 socialized) and six solitary kittens. In addition, 19 kittens were born on campus, 14 of which were born to immigrant pregnant females. Unsocialized adult immigrants were absorbed into the resident campus population. Where possible, socialized adult immigrants, solitary kittens, and campus-born kittens were removed from campus through rehoming. Overall, reasons for reductions in the cat population (original residents, immigrants, campus-born kittens; n = 122) included rehoming or return to owner (30%), death/euthanasia (30%) and disappearance (29%). This successful animal management program received some initial funding from the university to support desexing, but was subsequently funded through donations, and continues with the university’s approval and support.
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There is a need for effective and humane management tools to manage urban stray cats and minimise negative impacts associated with stray cats. One such tool is targeted trap-neuter-return (TTNR), but no concerted implementation of this technique or formal assessments have been reported. To address this deficit, a TTNR programme was implemented and assessed in one Auckland suburb from May 2015 to June 2016; the programme sterilised and returned 348 cats (4.2 cats/1000 residents). Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned (independently of the TTNR programme); and neonatal/underage euthanasias. Incoming stray felines, underage euthanasias, and unsocialised stray cat euthanasias were all reduced for the targeted suburb when compared for the years before and after the programme (the percentage reduction in these parameters was −39, −17, −34, −7, and −47, respectively). These outcome measures had a greater reduction in the targeted suburb compared to the Auckland suburbs not targeted by the TTNR programme (p < 0.01), although causation cannot be inferred, as a variety of reasons could have contributed to the changes. This pilot programme suggests that TTNR could be a valuable, humane cat management tool in urban New Zealand, and further assessment is warranted.
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Available evidence indicates that overall levels of feline intake and euthanasia at U.S. shelters have significantly declined in recent decades. Nevertheless, millions of cats, many of them free-roaming, continue to be admitted to shelters each year. In some locations, as many as 70% of cats, perhaps up to one million or more per year nationally, are euthanized. New approaches, including return-to-field (RTF) and targeted trap-neuter-return (TNR) appear to have transformative potential. The purpose of the present study was to examine changes in feline intake and euthanasia, as well as additional associated metrics, at a municipal animal shelter in Albuquerque, New Mexico, after institutionalized RTF and targeted TNR protocols, together referred to as a community cat program (CCP), were added to ongoing community-based TNR efforts and a pilot RTF initiative. Over the course of the CCP, which ran from April 2012 to March 2015, 11,746 cats were trapped, sterilized, vaccinated, and returned or adopted. Feline euthanasia at the Albuquerque Animal Welfare Department (AAWD) declined by 84.1% and feline intake dropped by 37.6% over three years; the live release rate (LRR) increased by 47.7% due primarily to these reductions in both intake and euthanasia. Modest increases in the percentage of cats returned to owner (RTO) and the adoption rate were also observed, although both metrics decreased on an absolute basis, while the number of calls to the city about dead cats declined.
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Article impact statement: Misinformation campaigns create false doubt about free‐ranging cat impacts, hinder efforts to manage cat numbers and conserve biodiversity.
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Simple Summary Strong public support in the United States for the non-lethal management of free-roaming cats has prompted an increase in the practice of trap-neuter-return (TNR) over the past quarter-century, yet a paucity of analyzable data exists. Data sets collected by citizen scientists are likely to play an important role in filling this information void. A citizen scientist in Chicago, Illinois, recorded significant reductions in a free-roaming cat population as the result of a neighborhood TNR program. Colony populations, when grouped by the number of years enrolled in the program, declined by a mean of 54% from entry and 82% from peak levels. Results from concurrent TNR programs in the Chicago area are compatible with these findings. Abstract The use of trap-neuter-return (TNR) as a method of managing free-roaming cat populations has increased in the United States in recent decades. Historically, TNR has been conducted most often at a grassroots level, which has led to inconsistent data collection and assessment practices. Consequently, a paucity of analyzable data exists. An initiative is underway to standardize TNR program data collection and assessment. However, it could be some time before scientifically sound protocols are implemented on a broad scale. In the interim, sets of data collected by nascent citizen scientists offer valid opportunities to evaluate grassroots TNR programs. The purpose of the present study was to examine the effectiveness of a TNR program conducted by a citizen scientist located in Chicago, Illinois, where a county law permitting TNR was enacted in 2007. Colony populations, when grouped by the number of years enrolled in the program, declined by a mean of 54% from entry and 82% from peak levels. Results from coexistent TNR programs in the Chicago area are consistent with these findings.
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The use of trap-neuter-return (TNR) as a humane alternative to the lethal management of free-roaming cats has been on the rise for several decades in the United States; however a relative paucity of data from TNR programs exists. An iconic community-wide TNR effort; initiated in 1992 and renowned for having eliminated hundreds of free-roaming cats from the Newburyport; Massachusetts waterfront; is cited repeatedly; yet few details appear in the literature. Although the presence of feline population data was quite limited; a detailed narrative emerged from an examination of contemporaneous reports; extant TNR program documents; and stakeholder testimony. Available evidence indicates that an estimated 300 free-roaming cats were essentially unmanaged prior to the commencement of the TNR program; a quick reduction of up to one-third of the cats on the waterfront was attributed to the adoption of sociable cats and kittens; the elimination of the remaining population; over a 17-year period; was ascribed to attrition. These findings illuminate the potential effectiveness of TNR as a management practice; as well as call attention to the need for broad adoption of systematic data collection and assessment protocols.
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Padded leg-hold live traps were used as the primary removal technique in the successful eradication of feral cats Felis silvestris catus from San Nicolas Island, California, USA. Risk of injury to endemic San Nicolas Island foxes Urocyon littoralis dickeyi, a similarly sized and more abundant non-target species, was mitigated by using a smaller trap size, modifying the trap and trap set to reduce injuries, and utilising a trap monitoring system to reduce time animals spent in traps. Impacts to foxes during the eradication campaign were further reduced by having a mobile veterinary hospital on island to treat injured foxes. Compared to other reported fox trapping efforts, serious injuries were reduced 2-7 times. Trapping efforts exceeded animal welfare standards, with 95% of fox captures resulting in minor or no injuries. Older foxes were more likely to receive serious injury. Fox captures were also reduced through aversive conditioning, with initial capture events providing a negative stimulus to prevent recaptures. Fox capture rates decreased up to six times during seven months of trapping, increasing trap availability for cats, and improving the efficacy of the cat eradication program. No aspect of the first capture event was significantly linked to the chance of recapture.
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Projects to eradicate invasive species from islands are a high priority for conservation. Here we describe the process used to successfully eradicate an introduced carnivore on an island where a native carnivore of similar size was also present. We primarily used padded leg-hold live trapping to capture feral cats (Felis silvestris catus). Trapped feral cats were transported off-island and housed in a permanent enclosure on the continent. We used additional methods, such as tracking dogs and spotlight hunting, to detect and remove more-difficult individuals. Project implementation caused no significant negative impacts to the endemic San Nicolas Island fox (Urocyon littoralis dickey) population. Mitigation measures included on-site veterinary resources, modified padded leg-hold live traps, conditioned trap aversion, a trap monitoring system and personnel training. To confirm eradication, we utilized camera traps and sign search data in a model to predict project success. A key part of the success of this project was the partnerships formed between NGOs, and government organizations. With support from the partnership, the use of innovative technology to improve traditional trapping methods allowed feral cats to be removed effectively in the presence of a native species occupying a similar niche. This project shows that strong partnerships, innovative methods, and use of technology can provide the conditions to eradicate invasive species when major barriers to success exist.
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Context Feral cats (Felis catus) threaten biodiversity in many parts of the world, including Australia. Low-level culling is often used to reduce their impact, but in open cat populations the effectiveness of culling is uncertain. This is partly because options for assessing this management action have been restricted to estimating cat activity rather than abundance. Aims We measured the response, including relative abundance, of feral cats to a 13-month pulse of low-level culling in two open sites in southern Tasmania. Methods To do this we used remote cameras and our analysis included identification of individual feral cats. We compared estimates of relative abundance obtained via capture-mark-recapture and minimum numbers known to be alive, and estimates of activity obtained using probability of detection and general index methods, pre- and post-culling. We also compared trends in cat activity and abundance over the same time period at two further sites where culling was not conducted. Key results Contrary to expectation, the relative abundance and activity of feral cats increased in the cull-sites, even though the numbers of cats captured per unit effort during the culling period declined. Increases in minimum numbers of cats known to be alive ranged from 75% to 211% during the culling period, compared with pre- and post-cull estimates, and probably occurred due to influxes of new individuals after dominant resident cats were removed. Conclusions Our results showed that low-level ad hoc culling of feral cats can have unwanted and unexpected outcomes, and confirmed the importance of monitoring if such management actions are implemented. Implications If culling is used to reduce cat impacts in open populations, it should be as part of a multi-faceted approach and may need to be strategic, systematic and ongoing if it is to be effective.
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Large populations of free-roaming cats (FRCs) generate ongoing concerns for welfare of both individual animals and populations, for human public health, for viability of native wildlife populations, and for local ecological damage. Managing FRC populations is a complex task, without universal agreement on best practices. Previous analyses that use simulation modeling tools to evaluate alternative management methods have focused on relative efficacy of removal (or trap-return, TR), typically involving euthanasia, and sterilization (or trap-neuter-return, TNR) in demographically isolated populations. We used a stochastic demographic simulation approach to evaluate removal, permanent sterilization, and two postulated methods of temporary contraception for FRC population management. Our models include demographic connectivity to neighboring untreated cat populations through natural dispersal in a metapopulation context across urban and rural landscapes, and also feature abandonment of owned animals. Within population type, a given implementation rate of the TR strategy results in the most rapid rate of population decline and (when populations are isolated) the highest probability of population elimination, followed in order of decreasing efficacy by equivalent rates of implementation of TNR and temporary contraception. Even low levels of demographic connectivity significantly reduce the effectiveness of any management intervention, and continued abandonment is similarly problematic. This is the first demographic simulation analysis to consider the use of temporary contraception and account for the realities of FRC dispersal and owned cat abandonment.
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Cat impoundments were increasing at the municipal San Jose animal shelter in 2009, despite long-term successful low cost sterilization programs and attempts to lower the euthanasia rate of treatable-rehabilitatable impounds beginning in 2008. San Jose Animal Care and Services implemented a new strategy designed to control overall feral cat reproduction by altering and returning feral cats entering the shelter system, rather than euthanizing the cats. The purpose of this case study was to determine how the program affected the shelter cat intakes over time. In just over four years, 10,080 individual healthy adult feral cats, out of 11,423 impounded at the shelter during this time frame, were altered and returned to their site of capture. Included in the 11,423 cats were 862 cats impounded from one to four additional times for a total of 958 (9.5%) recaptures of the previously altered 10,080 cats. The remaining 385 healthy feral cats were euthanized at the shelter from March 2010 to June 2014. Four years into the program, researchers observed cat and kitten impounds decreased 29.1%; euthanasia decreased from over 70% of intakes in 2009, to 23% in 2014. Euthanasia in the shelter for Upper Respiratory Disease decreased 99%; dead cat pick up off the streets declined 20%. Dog impounds did not similarly decline over the four years. No other laws or program changes were implemented since the beginning of the program.
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Approximately 2-3 million cats enter animal shelters annually in the United States. A large proportion of these are unowned community cats that have no one to reclaim them and may be too unsocialized for adoption. More than half of impounded cats are euthanased due to shelter crowding, shelter-acquired disease or feral behavior. Trap-neuter-return (TNR), an alternative to shelter impoundment improves cat welfare and reduces the size of cat colonies, but has been regarded as too impractical to reduce cat populations on a larger scale or to limit shelter cat intake. The aim of this study was to assess the effect of TNR concentrated in a region of historically high cat impoundments in a Florida community. A 2 year program was implemented to capture and neuter at least 50% of the estimated community cats in a single 11.9 km2 zip code area, followed by return to the neighborhood or adoption. Trends in shelter cat intake from the target zip code were compared to the rest of the county. A total of 2,366 cats, representing ~54% of the projected community cat population in the targeted area, were captured for the TNR program over the 2 year study period. After 2 years, per capita shelter intake was 3.5-fold higher and per capita shelter euthanasia was 17.5-fold higher in the non-target area than in the target area. Shelter cat impoundment from the target area where 60 cats/1,000 residents were neutered annually decreased 66% during the 2 year study period, compared to a decrease of 12% in the non-target area, where only 12 cats/1,000 residents were neutered annually. High-impact TNR combined with the adoption of socialized cats and nuisance resolution counseling for residents is an effective tool for reducing shelter cat intake.
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Simple Summary This study found that less than 15% of Thai nationals engaged in semi-ownership practices, such as feeding, but that few of these stray cats and dogs had been sterilised. Intentions to sterilise in the future were predicted by religious beliefs, attitudes towards sterilisation, perceived pressure from others, and beliefs about personal capacity to sterilise (such as affordability). Community awareness campaigns that approach the issue of sterilisation in a way that is consistent with cultural and religious traditions using Thai role models, such as veterinarians, may go some way in reducing stray animal population growth. Abstract The aim of this study was to identify the prevalence of cat and dog semi-ownership in Thailand and factors that predict sterilisation. Semi-ownership was defined as interacting/caring for a companion animal that the respondent does not own, such as a stray cat or dog. A randomised telephone survey recruited 494 Thai nationals residing in Thailand. The findings revealed that 14% of respondents (n = 71) engaged in dog semi-ownership and only 17% of these dogs had been sterilised. Similarly, 11% of respondents (n = 55) engaged in cat semi-ownership and only 7% were known to be sterilised. Using Hierarchical Multiple Regression, the findings showed that 62% and 75% of the variance in intentions to sterilise semi-owned dogs and cats, respectively, was predicted by religious beliefs, and psychosocial factors such as attitudes, perceived pressure from others, and perceived behavioural control. Community awareness campaigns that approach the issue of sterilisation in a way that is consistent with cultural and religious traditions using Thai role models, such as veterinarians, may go some way in reducing stray animal population growth.
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The measurable benefits of animal control programs are unknown and the aim of this study was to determine the impact of these programs on pet population changes. A prospective cross-sectional study of 1000 households was implemented in 2005 to evaluate characteristics of the owned and unowned population of dogs and cats in Santa Clara County, California. The same population was previously studied 12 years earlier. During this time period, the county instituted in 1994 and then subsequently disestablished a municipal spay/neuter voucher program for cats. Dog intakes declined from 1992-2005, as they similarly did for an adjacent county (San Mateo). However, cat intakes declined significantly more in Santa Clara County than San Mateo, with an average annual decline of approximately 700 cats for the 12 year period. Time series analysis showed a greater than expected decline in the number of cats surrendered to shelters in Santa Clara County during the years the voucher program was in effect (1994-2005). The net savings to the county by reducing the number of cat shelter intakes was estimated at approximately $1.5 million. The measurable benefits of animal control programs are unknown and the aim of this study was to determine the impact of these programs on pet population changes.
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Our goal was to determine whether it is more cost-effective to control feral cat abundance with trap-neuter-release programs or trap and euthanize programs. Using STELLA 7, systems modeling software, we modeled changes over 30 years in abundance of cats in a feral colony in response to each management method and the costs and benefits associated with each method . We included costs associated with providing food, veterinary care, and microchips to the colony cats and the cost of euthanasia, wages, and trapping equipment in the model. Due to a lack of data on predation rates and disease transmission by feral cats the only benefits incorporated into the analyses were reduced predation on Wedge-tailed Shearwaters (Puffinus pacificus). When no additional domestic cats were abandoned by owners and the trap and euthanize program removed 30,000 cats in the first year, the colony was extirpated in at least 75% of model simulations within the second year. It took 30 years for trap-neuter-release to extirpate the colony. When the cat population was supplemented with 10% of the initial population size per year, the colony returned to carrying capacity within 6 years and the trap and euthanize program had to be repeated, whereas trap-neuter-release never reduced the number of cats to near zero within the 30-year time frame of the model. The abandonment of domestic cats reduced the cost effectiveness of both trap-neuter-release and trap and euthanize. Trap-neuter-release was approximately twice as expensive to implement as a trap and euthanize program. Results of sensitivity analyses suggested trap-neuter-release programs that employ volunteers are still less cost-effective than trap and euthanize programs that employ paid professionals and that trap-neuter-release was only effective when the total number of colony cats in an area was below 1000. Reducing the rate of abandonment of domestic cats appears to be a more effective solution for reducing the abundance of feral cats.
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The domestic cat is an invasive species that often causes great impacts where introduced due to its high predatory and reproductive potential, especially on islands. In this study, carried out on Ilha Grande (RJ, Brazil), we aimed to: i) estimate the population density of domestic cats, ii) calculate the number of animals preyed upon annually by domestic cats, and iii) evaluate the efficiency of methods to control the cat population. We used the Vortex program to project the population growth of domestic cats in fifty years, and simulated different scenarios of population control (without control, castration, spay and harvest). Population density of owned cats was 662 cats/km². The annual predation rate was 1.97 prey animals/cat which is an average of 1497.96 prey/year. The population would only be reduced if 70% of females were spayed or removed annually. Measures to control the domestic cat population must be undertaken urgently, since uncontrolled growth of this predator has the potential to seriously impact the biodiversity of Ilha Grande.
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Feral cats are directly responsible for a large percentage of global extinctions, particularly on islands. We reviewed feral cat eradication programs with the intent of providing information for future island conservation actions. Most insular cat introductions date from the nineteenth and twentieth centuries, whereas successful eradication programs have been carried out in the last 30 years, most in the last decade. Globally, feral cats have been removed from at least 48 islands: 16 in Baja California (Mexico), 10 in New Zealand, 5 in Australia, 4 in the Pacific Ocean, 4 in Seychelles, 3 in the sub-Antarctic, 3 in Macaronesia (Atlantic Ocean), 2 in Mauritius, and 1 in the Caribbean. The majority of these islands (75%; n= 36) are small (≤5 km²). The largest successful eradication campaign took place on Marion Island (290 km²), but cats have been successfully removed from only 10 islands (21%) of ≥10 km². On Cousine Island (Seychelles) cat density reached 243 cats/km², but on most islands densities did not exceed 79.2 cats/km² (n= 22; 81%). The most common methods in successful eradication programs were trapping and hunting (often with dogs; 91% from a total of 43 islands). Frequently, these methods were used together. Other methods included poisoning (1080; monofluoracetate in fish baits; n= 13; 31%), secondary poisoning from poisoned rats (n= 4; 10%), and introduction of viral disease (feline panleucopaenia; n= 2; 5%). Impacts from cat predation and, more recently, the benefits of cat eradications have been increasingly documented. These impacts and benefits, combined with the continued success of eradication campaigns on larger islands, show the value and role of feral cat eradications in biodiversity conservation. However, new and more efficient techniques used in combination with current techniques will likely be needed for success on larger islands.
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Since their introduction in 1949, feral cats have caused extensive damage to seabird populations on sub-Antarctic Marion Island, Indian Ocean. This paper reports on the first four years of an eradication programme launced in 1986. Eight hundred and seventy-two cats were shot dead and 80 trapped during 14 725 hours of hunting. Cats sighted per hour of night hunting and kills per hour decreased dramatically. Hunting success (cats killed as a proportion of those seen) decreased. The only reliable indication of the decrease in density as a result of hunting was the decrease in the number of cats seen per hour of night hunting. By the end of the third season it was apparent that hunting alone was no longer removing sufficient animals to maintain the population decline, and trapping was incorporated into the eradication programme.
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Worldwide domestic and feral cat (Felis catus) numbers have increased. Concerns regarding high populations of feral cats in urban areas include wildlife predation, public nuisance, and disease. This study aimed to estimate the size of the feral cat population on 5 campuses of the University of KwaZulu-Natal, South Africa, to determine whether sterilization has an effect and to make management recommendations. The study used both the total count and mark-recapture methods to estimate the feral cat population on each campus. The study chose a noninvasive method of taking photographs to "mark" individuals and record those who were sterilized. The study estimated a total of 186 cats on all campuses and density at 161 cats km(-2). There was a negative relationship between sterilization and numbers. Sites with higher sterilization showed a lower proportion of younger cats. At the average sterilization of 55%, the population, according to predictions, would remain stable at fecundity, survival, and immigration rates reported by cat caretakers. However, caretakers underestimated cat abundance by 7 ± 37 SD%. Caretakers' feral cat sterilization and feeding programs appear to provide a service to the university community. Key management recommendations were to increase sterilization to 90% to reduce the population over the long term and to raise funds to support the costs incurred by voluntary cat caretakers.
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Many jurisdictions have adopted programs to manage feral cats by trap-neuter-return (TNR), in which cats are trapped and sterilized, then returned to the environment to be fed and cared for by volunteer caretakers. Most conservation biologists probably do not realize the extent and growth of this practice and that the goal of some leading TNR advocates is that cats ultimately be recognized and treated as "protected wildlife." We compared the arguments put forth in support of TNR by many feral cat advocates with the scientific literature. Advocates promoting TNR often claim that feral cats harm wildlife only on islands and not on continents; fill a natural or realized niche; do not contribute to the decline of native species; and are insignificant vectors or reservoirs of disease. Advocates also frequently make claims about the effectiveness of TNR, including claims that colonies of feral cats are eventually eliminated by TNR and that managed colonies resist invasion by other cats. The scientific literature contradicts each of these claims. TNR of feral cats is primarily viewed and regulated as an animal welfare issue, but it should be seen as an environmental issue, and decisions to implement it should receive formal environmental assessment. Conservation scientists have a role to play by conducting additional research on the effects of feral cats on wildlife and by communicating sound scientific information about this problem to policy makers.
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To describe the characteristics of unowned, free-roaming cats and their caretakers who participated in a trap-neuter-return (TNR) program and to determine the effect of the program on free-roaming cat colonies. Prospective study. 101 caretakers of 920 unowned, free-roaming cats in 132 colonies in north central Florida. Most (85/101; 84%) caretakers were female. The median age was 45 years (range, 19 to 74 years). Most (89/101; 88%) caretakers owned pets and of those, most (67/101; 66%) owned cats. The major reasons for feeding free-roaming cats were sympathy and love of animals. Most caretakers reported that the cats they cared for were too wild to be adopted, but many also reported that they considered the cats to be like pets. The total surveyed cat population was 920 before participation in TNR and 678 after TNR. Mean colony size was 7 cats before TNR and 5.1 cats after TNR. Most cats lived on the caretaker's property. At the time of the survey, 70% (644/920) of the cats had been neutered. The decrease in the surveyed free-roaming cat population was attributed to a reduction in births of new kittens, adoptions, deaths, and disappearances. Recognition of the human-animal bond that exists between caretakers and the feral cats they feed may facilitate the development of effective control programs for feral cat populations.
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To evaluate the effect of a long-term trap-neuter-return program, with adoption whenever possible, on the dynamics of a free-roaming cat population. Observational epidemiologic study. 155 unowned free-roaming cats. Free-roaming cats residing on a university campus were trapped, neutered, and returned to the environment or adopted over an 11-year period. During the observation period (January 1991 to April 2002), 75% of the cats were feral, and 25% were socialized. Kittens comprised 56% of the original population. Male cats were slightly more numerous (55%) than females. At the conclusion of the observation period, 47% of the cats had been removed for adoption, 15% remained on site, 15% had disappeared, 11% were euthanatized, 6% had died, and 6% had moved to the surrounding wooded environment. Trapping began in 1991; however, a complete census of cats was not completed until 1996, at which time 68 cats resided on site. At completion of the study in 2002, the population had decreased by 66%, from 68 to 23 cats (of which 22 were feral). No kittens were observed on site after 1995, but additional stray or abandoned cats continued to become resident. New arrivals were neutered or adopted before they could reproduce. A comprehensive long-term program of neutering followed by adoption or return to the resident colony can result in reduction of free-roaming cat populations in urban areas.
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In August 1998, Texas AM University implemented on campus a trap-test-vaccinate-alter-return-monitor (TTVARM) program to manage the feral cat population. TTVARM is an internationally recognized term for trapping and neutering programs aimed at management of feral cat populations. In this article we summarize results of the program for the period August 1998 to July 2000. In surgery laboratories, senior veterinary students examined cats that were humanely trapped once a month and tested them for feline leukemia and feline immunodeficiency virus infections, vaccinated, and surgically neutered them. They euthanized cats testing positive for either infectious disease. Volunteers provided food and observed the cats that were returned to their capture sites on campus and maintained in managed colonies. The program placed kittens and tame cats for adoption; cats totaled 158. Of the majority of 158 captured cats, there were less kittens caught in Year 2 than in Year 1. The proportion of tame cats trapped was significantly greater in Year 2 than in Year 1. The prevalence found for feline leukemia and feline immunodeficiency virus ELISA test positives was 5.8% and 6.5%, respectively. Following surgery, 101 cats returned to campus. The project recaptured, retested, and revaccinated more than one-fourth of the cats due for their annual vaccinations. The program placed 32 kittens, juveniles, and tame adults for adoption. The number of cat complaints received by the university's pest control service decreased from Year 1 to Year 2.
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To determine reproductive capacity of naturally breeding free-roaming domestic cats and kitten survival rate. Prospective cohort and retrospective cross-sectional study. 2,332 female cats brought to a trap-neuter-return clinic for neutering and 71 female cats and 171 kittens comprising 50 litters from a cohort study of feral cats in managed colonies. Data collected for all cats included pregnancy, lactation, and estrus status and number of fetuses for pregnant cats. Additional data collected for feral cats in managed colonies included numbers of litters per year and kittens per litter, date of birth, kitten survival rate, and causes of death. Pregnant cats were observed in all months of the year, but the percentage of cats found to be pregnant was highest in March, April, and May. Cats produced a mean of 1.4 litters/y, with a median of 3 kittens/litter (range, 1 to 6). Overall, 127 of 169 (75%) kittens died or disappeared before 6 months of age. Trauma was the most common cause of death. Results illustrate the high reproductive capacity of free-roaming domestic cats. Realistic estimates of the reproductive capacity of female cats may be useful in assessing the effectiveness of population control strategies.
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To evaluate the efficacy of trap-neuter-return and trap-euthanatize management strategies for controlling urban free-roaming cat populations by use of matrix population models. Prospective study. Estimates of free-roaming cat populations in urban environments. Data from the literature describing the biology of free-roaming cat populations in urban environments were gathered. A matrix population model was developed with a range of high and low survival and fecundity values and all combinations of those values. The response of population growth rate to a range of management actions was assessed with an elasticity analysis. All possible combinations of survival and fecundity values of free-roaming cats led to predictions of rapid, exponential population growth. The model predicted effective cat population control by use of annual euthanasia of > or = 50% of the population or by annual neutering of > 75% of the fertile population. Elasticity analyses revealed that the modeled population was most susceptible to control through euthanasia. Free-roaming cat populations have a high intrinsic growth rate, and euthanasia is estimated to be more effective at reducing cat populations than trap-neuter-return programs.
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To evaluate 2 county trap-neuter-return (TNR) programs for feral cat population management via mathematical modeling. Theoretical population model. Feral cats assessed from 1992 to 2003 in San Diego County, California (n = 14,452), and from 1998 to 2004 in Alachua County, Florida (11,822). Data were analyzed with a mathematical Ricker model to describe population dynamics of the feral cats and modifications to the dynamics that occurred as a result of the TNR programs. In both counties, results of analyses did not indicate a consistent reduction in per capita growth, the population multiplier, or the proportion of female cats that were pregnant. Success of feral cat management programs that use TNR can be monitored with an easily collected set of data and statistical analyses facilitated by population modeling techniques. Results may be used to suggest possible future monitoring and modification of TNR programs, which could result in greater success controlling and reducing feral cat populations.
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Feral cats (Felis catus) have devastated wildlife globally. In Australia, feral cats are implicated in most recent mammal extinctions and continue to threaten native species. Cat control is a high-profile priority for Australian policy, research and management. To develop the evidence-base to support this priority, we first review information on cat presence/absence on Australian islands and mainland cat-proof exclosures, finding that cats occur across >99.8% of Australia's land area. Next, we collate 91 site-based feral cat density estimates in Australia and examine the influence of environmental and geographic influences on density. We extrapolate from this analysis to estimate that the feral cat population in natural environments fluctuates between 1.4 million (95% confidence interval: 1.0–2.3 million) after continent-wide droughts, to 5.6 million (95% CI: 2.5–11 million) after extensive wet periods. We estimate another 0.7 million feral cats occur in Australia's highly modified environments (urban areas, rubbish dumps, intensive farms). Feral cat densities are higher on small islands than the mainland, but similar inside and outside conservation land. Mainland cats reach highest densities in arid/semi-arid areas after wet periods. Regional variation in cat densities corresponds closely with attrition rates for native mammal fauna. The overall population estimate for Australia's feral cats (in natural and highly modified environments), fluctuating between 2.1 and 6.3 million, is lower than previous estimates, and Australian feral cat densities are lower than reported for North America and Europe. Nevertheless, cats inflict severe impacts on Australian fauna, reflecting the sensitivity of Australia's native species to cats and reinforcing that policy, research and management to reduce their impacts is critical.
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Domestic cat (Felis catus L.) advocates have formed coalitions whose goals are to promote the welfare of cats through the use of a specific nonlethal population control method. This method consists of trapping, neutering, and releasing cats into supervised cat colonies located on private and public lands, including state and county parks and natural areas. Advocates believe that this method will help reduce the number of unwanted cats and stabilize the population of unwanted cats over time. Furthermore, advocates claim that established colonies are temporary in nature and will decrease in size over time through death and adoption. This claim was tested through photographic and observational capture-recapture techniques in Miami-Dade County, Florida, USA, in two Metro-Dade County parks (A. D. Barnes Park and Crandon Marina). Although the number of original colony members decreased over time, illegal dumping of unwanted cats and the attraction of stray cats to provisioned food offset reductions in cat numbers caused by death and adoption. Furthermore, overall population size of the colony at A. D. Barnes Park increased over time, and at Crandon Marina neither decreased nor increased over time. Our study suggests that this method is not an effective means to control the population of unwanted cats and confirms that the establishment of cat colonies on public lands encourages illegal dumping and creates an attractive nuisance. We recommend that advocates of cat colonies seek a long-term solution to the pet overpopulation issue by redirecting their efforts toward the underlying problem of managing irresponsible pet owners.
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Trap-neuter-return (TNR) for cat management is transitioning from an enterprise driven mainly by an urge to 'help' into an enterprise that draws useful guidance and precedent from the fields of population biology and wildlife management. This transition is in its infancy, however. At the present time many TNR programs do not produce substantial and persistent reductions in cat populations, and those that do often fail to effectively document this achievement or to publicize their success. As a result, TNR has become increasingly controversial, with TNR advocates and wildlife conservationists often staking out fundamentally incompatible positions. This may ultimately prove to be an unproductive debate, since public opinion in developed countries is unlikely to support a total abandonment of TNR in favor of widespread cat management using lethal methods, and since wildlife advocates are unlikely to support TNR as it is typically practiced. In contrast, improving the effectiveness of TNR as a population management tool can benefit both cats and wildlife, potentially on a broad scale. Making these advancements requires the diligent promotion, dissemination and adoption of tools like population modeling, population monitoring and adaptive management. By virtue of their training and exposure to the scientific method, veterinarians are uniquely well positioned to translate the more technical aspects of these approaches to TNR practitioners, and to facilitate their wider use. The purpose of this review is to describe for a veterinary audience how to facilitate more effective sterilization-based management of outdoor cats, using a combination of theoretical knowledge derived from population modeling and empirical knowledge derived from population monitoring. Using both of these information sources synergistically can offer a viable pathway to better management outcomes. © The Author(s) 2015.
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Study undertaken on Marion Island, which supported a feral cat population, revealed that the conditions approached the optimal for the release of a feline parvovirus. The initial success of this procedure is evaluated and compared with the dissemination of other viruses affecting vertebrates, for the purpose of biological control.-from Author
Article
The feral Cat (Felis catus) population on Macquarie Island was targeted for eradication between 1996 and 2002, with 761 cats captured during this period. After 22 years of cat control from 1974 integrated with control programmes for other pests, effort intensified for 2 years before a dedicated eradication programme began in 1998. The primary knock-down for the eradication used cage trapping and shooting, with most surviving cats captured with leg-hold traps. A total of 6298 field days and 216 574 trap nights were recorded in this operation. Factors contributing to the success of the programme included extensive planning, increased staff numbers at critical times, better access to remote areas of the island, introduction of leg-hold traps, sufficient operational funding and good collaboration between government agencies operating on the island. The programme would have benefited from earlier deployment of detector dogs and better posteradication monitoring of a broader range of native species impacted by cats. The successful eradication of cats from Macquarie Island, being the second largest achieved to date, provides valuable experience for cat eradication attempts on other large remote islands. This programme relied on ground-based techniques with minimal use of poisons and provides possible options for sites where broad-scale poisoning, or where aerial distribution of poisons, cannot be used.
Article
Global estimates of the number of domestic cats (Felis catus) are >400million. Issues associated with free- roaming cats are of global importance because of animal-welfare and public-health concerns and impacts on native wildlife throughpredation,competitionanddiseasetransmission.IntheUnitedStates,proposedcontrolsolutionsformanagingurban free-roaming cat populations include euthanasia and trap-neuter-return (TNR) programs. We evaluated control methods usingademographicpopulationmodelfora25-yearperiod,withparametersestimatedfromanunmanaged,free-roamingcat populationinTexas.WemodelledeuthanasiaandTNRat25%,50%and75%implementationratesanda50:50combination of euthanasia and TNR at 25%, 50%, 75% and 100% implementation rates for 0%, 25% and 50% maximum immigration rates. We compared final population size, total number of cats treated and treatment effort relative to population reduction. Population decreases were comparable among euthanasia, TNR and a 50:50 combination for all treatment rates when the immigrationratewas0%;however,theywerehigherforeuthanasiaat25%and50%maximumimmigrationrates.Euthanasia required higher treatment effort than TNR. Our results indicate that immigration must be prevented and high (>50%) treatment rates implemented to reduce free-roaming cat populations.
Article
The size of urban cat colonies is limited only by the availability of food and shelter; therefore, their population growth challenges all known population control programs. To test a new population control method, a free-roaming feral cat colony at the Zoological Park in the city of Rio de Janeiro was studied, beginning in 2001. The novel method consisted of performing a hysterectomy on all captured female cats over 6 months of age. To estimate the size of the colony and compare population from year to year, a method of capture-mark-release-recapture was used. The aim was to capture as many individuals as possible, including cats of all ages and gender to estimate numbers of cats in all population categories. Results indicated that the feral cat population remained constant from 2001 to 2004. From 2004 to 2008, the hysterectomy program and population estimates were performed every other year (2006 and 2008). The population was estimated to be 40 cats in 2004, 26 in 2006, and 17 cats in 2008. Although pathogens tend to infect more individuals as the population grows older and maintains natural behavior, these results show that free-roaming feral cat colonies could have their population controlled by a biannual program that focuses on hysterectomy of sexually active female cats.
Article
In Italy, which is rabies-free, the national Law No. 281 [Legge Nazionale 14 agosto 1991. No. 281: Legge Quadro in materia di animali di affezione e prevenzione del randagismo. Gazz. Uff. Rep. Ital. no 203 del 30 agosto 1991: p. 3] on the management of pets and on the control of feral cats has introduced the no-kill policy for this species. Thus, "trap-neuter-release" (TNR) programs have been carried out for >10 years. In this paper we present data on registered colonies and censused cats in Rome from 1991 to 2000; the results of the neutering campaign from 1991 to 2000; and a survey, on 103 cat colonies, on the effects of demographic control of urban feral-cat colonies in the city of Rome, carried out by the local Veterinary Public Services (VPS) in collaboration with the associations of cat care-takers. In 10 years almost 8000 were neutered and reintroduced in their original colony. The spay/neuter campaigns brought about a general decrease in cat number but the percentage of cat immigration (due to abandonment and spontaneous arrival) is around 21%. This suggests that all these efforts without an effective education of people to control the reproduction of house cats (as a prevention for abandonment) are a waste of money, time and energy.
Cat wars break out in New Zealand
  • K Adam
  • Adam, K.
Adam, K. (2013). Cat wars break out in New Zealand. Available online: https://www. theguardian.com/world/2013/may/21/cat-wars-new-zealand-morgan.
Pet Ownership in Australia
  • Animal Medicines Australia
Animal Medicines Australia (2016). Pet Ownership in Australia. Available online: http://animalmedicinesaustralia.org.au/wp-content/uploads/2016/11/AMA_Pet-Ownership-in-Australia-2016-Report_sml.pdf.
Should the cat take the rap?
  • I Anderson
  • Anderson, I.
Anderson, I. (1994). Should the cat take the rap? New Scientist, 21 May 1994. Available online: https://www.newscientist.com/article/mg14219262 300/ [Accessed 27 July 2018].
The AVMA has produced reports including information on pet demographics every five years from
AVMA (various from 1987 to 2012). The AVMA has produced reports including information on pet demographics every five years from 1986 to 2011 (e.g., US Pet Ownership and Demographics Sourcebook, 1996). Schaumburg, IL: American Veterinary Medical Association.