A review of cat behavior in relation to disease risk and management options

Density and Home Range of Cats in a Small Inhabited Mediterranean Island

There is growing concern about effectively controlling cat populations due to their impact on biodiversity, especially on islands. To plan this management, it is essential to know the cat population size, sterilization rates, and space they use. Small inhabited islands can have very high cat densities; thus, this study aimed to evaluate cat density and home range on a small tourist island in the Spanish Mediterranean. Surveys in the urban area identified individual cats using a photographic catalog, and camera trapping was conducted in the scrubland area. GPS devices were fitted on three urban cats. The overall cat density was estimated to be 308 cats/km2, varying between the urban area (1084 cats/km2) and the uninhabited scrubland (27 cats/km2). Urban cats had smaller average home ranges (0.38 ha or 1.25 ha, depending on the estimation method) compared to scrubland cats (9.53 ha). Penetration of scrubland cats into the urban area was not detected. These results indicate that the urban area acts as a source of cats for the scrubland. Although the total sterilization rate was high (90.3%), the large cat population implies that the density would take over a decade to decrease to acceptable levels. Therefore, complementary measures for managing this cat population are recommended.

Serological detection of Rickettsia spp. and evaluation of blood parameters in pet dogs and cats from Bangkok and neighboring provinces

Rickettsiosis is caused by Orientia spp. and Rickettsia spp., arthropod-borne zoonotic intracellular bacteria. The close relationships between pet dogs, cats and owners increase the risk of rickettsial transmission, with limited studies on the seroprevalence in pets. This study investigated the prevalence of rickettsia exposure among dogs and cats in Bangkok and neighboring provinces. The samples from 367 dogs and 187 cats used in this study were leftover serum samples from routine laboratory testing stored at the Veterinary Teaching Hospital. In-house Enzyme-linked immunosorbent assay (ELISA) tests included IgG against the scrub typhus group (STG), typhus group (TG), and spotted fever group (SFG). The seroprevalence in pet dogs was 30.25% (111/367), including 21.53% for STG, 4.36% for TG, and 1.09% for SFG. Co-seroprevalence consisted of 2.72% for STG and TG, 0.27% for STG and SFG, and 0.27% for pangroup infection. The prevalence in cats was 62.56% (117/187), including 28.34% for STG, 4.28% for TG, and 6.42% for STG. Co-seroprevalence in cats consisted of STG and TG (4.28%), STG and SFG (5.35%), TG and SFG (3.21%), and three-group infection (10.69%). No significant difference in seroprevalence for the three serogroups was observed in any of the 64 districts sampled. The mean hematocrit level significantly decreased in seropositive dogs (P<0.05). Seropositive dogs and cats were detected in significantly greater numbers of anemia cases than nonanemia cases (P<0.05) (odds ratio: 7.93, 0.44, p = 0.00, p = 0.01). A significantly higher number of seropositive cats had decreased hemoglobin levels (P<0.05) (odds ratio: 3.63, p = 0.00). The seropositive samples significantly differed among older cats (P<0.05). These high exposures in pet dogs and cats could constitute important relationship dynamics between companion animals and rickettsial vectors. Significantly decreased hematocrit and hemoglobin levels indicated anemia in the exposed dogs and cats. The study findings will raise awareness of this neglected disease among pet owners and veterinary hospital personnel and aid in future public health preventative planning.

Community Engagement and the Effectiveness of Free-Roaming Cat Control Techniques: A Systematic Review

Although free-roaming and feral cat control techniques are often applied in human communities, community engagement is not always considered. A systematic literature review following an update of the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020) methodology was conducted to evaluate whether community engagement influences the effectiveness of control techniques, excluding culling, in managing cat populations. The degree of community engagement was estimated based on the number of roles reported during the application of the control technique, which included adoption, trapping, care, and/or education. Education followed by adoption was the determining factor in the decreasing cat populations over time. The limited evaluations of control technique effectiveness, narrow geographical scope, and our simple measure of engagement emphasize the need for more detailed studies. These studies should evaluate the effectiveness of control techniques, while considering community engagement more comprehensively.

Audience segmentation of New Zealand cat owners: Understanding the barriers and drivers of cat containment behavior

Free-roaming companion cats have a detrimental impact on the environment and are at risk of harm. Despite these negative impacts, it is the norm in New Zealand (NZ) to allow companion cats to roam freely and only a minority of cat owners practice cat containment. This study firstly sought to identify what factors act as barriers and drivers of NZ owners' participation in cat containment, and secondly whether NZ owners could be segmented into unique audiences based on the factors predicting their cat containment behavior. It was hypothesized that cat owners with greater capability, opportunity, and motivation to perform cat containment would have greater cat containment intentions and behavior. Furthermore, it was expected that at least three segments of cat owners would exist in NZ which differed significantly in the set of capability, opportunity and motivational factors predicting their cat containment behavior. A quantitative online cross-sectional survey of 395 NZ cat owners was conducted, measuring containment intentions and behavior, and capability, opportunity, and motivation to perform cat containment. Results from bivariate correlations and multiple regression demonstrated that capability, opportunity, and motivational factors predicted increased cat containment intentions and behavior. Latent profile analysis identified four distinct segments of cat owners with unique COM profiles; engaged (6%), receptive (17%), ambivalent (48%), and opposed (30%). Validation analysis demonstrated that these groups all differed significantly in their cat containment intentions and behaviors. From these findings theoretically grounded behavior change interventions can be developed to target the causes of non-participation in cat containment for each of the identified cat owner segments, thereby improving the management of free-roaming cats in NZ.

A global synthesis and assessment of free-ranging domestic cat diet

Free-ranging cats (Felis catus) are globally distributed invasive carnivores that markedly impact biodiversity. Here, to evaluate the potential threat of cats, we develop a comprehensive global assessment of species consumed by cats. We identify 2,084 species eaten by cats, of which 347 (16.65%) are of conservation concern. Islands contain threefold more species of conservation concern eaten by cats than continents do. Birds, reptiles, and mammals constitute ~90% of species consumed, with insects and amphibians being less frequent. Approximately 9% of known birds, 6% of known mammals, and 4% of known reptile species are identified in cat diets. 97% of species consumed are <5 kg in adult body mass, though much larger species are also eaten. The species accumulation curves are not asymptotic, indicating that our estimates are conservative. Our results demonstrate that cats are extreme generalist predators, which is critical for understanding their impact on ecological systems and developing management solutions.

Do cats mirror their owner? Paired exposure assessment using silicone bands to measure residential PAH exposure

It has been suggested that domestic animals can serve as sentinels for human exposures. In this study our objectives were to demonstrate that i) silicone collars can be used to measure environmental exposures of (domestic) animals, and that ii) domestic animals can be used as sentinels for human residential exposure. For this, we simultaneously measured polycyclic aromatic hydrocarbons (PAHs) using silicone bands worn by 30 pet cats (collar) and their owner (wristband). Collars and wristbands were worn for 7 days and analyzed via targeted Gas Chromatography-Mass Spectrometry (GC-MS). Demographics and daily routines were collected for humans and cats. Out of 16 PAHs, 9 were frequently detected (>50% of samples) in both wristbands and collars, of which Phenanthrene and Fluorene were detected in all samples. Concentrations of wristbands and collars were moderately correlated for these 9 PAHs (Median Spearman's r = 0.51 (range 0.16-0.68)). Determinants of PAH concentrations of cats and humans showed considerable overlap, with vacuum cleaning resulting in higher exposures and frequent changing of bed sheets in lower exposures. This study adds proof-of-principle data for the use of silicone collars to measure (domestic) animal exposure and shows that cats can be used as sentinels for human residential exposure.

Prevalence of feline chronic gingivostomatitis in feral cats and its risk factors

OBJECTIVES

This study investigated the prevalence of feline chronic gingivostomatitis in urban feral cats in South Korea and analysed its risk factors.

METHODS

Three hundred and forty-five feral cats that visited the hospital for neutering using a trap-neuter-return approach were screened for feline chronic gingivostomatitis based on clinical criteria. In addition, we determined if body weight, sex and the presence of tongue lesions are risk factors for feline chronic gingivostomatitis. The difference in severity due to the presence or absence of risk factors, and the relationship between gross findings and histopathological lesions, were analysed by grading lesion severity.

RESULTS

Feline chronic gingivostomatitis was diagnosed in 92 cats. Disease prevalence did not significantly differ with body weight and sex but was significantly related to tongue lesions.

CONCLUSIONS AND RELEVANCE

The prevalence of feline chronic gingivostomatitis in urban feral cats in South Korea was 26.6%. It was significantly more prevalent in cats that had tongue lesions. Severity was also significantly associated with tongue lesions. Feline chronic gingivostomatitis may be associated with an infectious agent that causes tongue lesions.

One-Year Surveillance of SARS-CoV-2 Exposure in Stray Cats and Kennel Dogs from Northeastern Italy

Dogs and cats are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). During the pandemic, several studies have been performed on owned cats and dogs, whereas limited data are available on the exposure to stray animals. The objective of this study was to investigate the exposure to SARS-CoV-2 of feral cats and kennel dogs in northeastern Italy, through serological and molecular methods. From May 2021 to September 2022, public health veterinary services collected serum, oropharyngeal, and rectal swab samples from 257 free-roaming dogs newly introduced to shelters, and from 389 feral cats examined during the routinely trap-neutered-return programs. The swabs were analyzed for viral RNA through a real-time reverse transcriptase PCR (rRT-PCR), and sera were tested for the presence of the specific antibody against SARS-CoV-2 (enzyme-linked immunosorbent assay). Serology was positive in nine dogs (9/257) and three cats (3/389), while two asymptomatic cats tested positive to rRT-PCR. One cat turned out to be positive both for serology and molecular analysis. In addition, this study described the case of a possible human-to-animal SARS-CoV-2 transmission in a cat that travelled in close contact to a COVID-19-positive refugee from Ukraine. This study shows that SARS-CoV-2 can infect, in natural conditions, stray cats and kennel dogs in northeastern Italy, although with a low prevalence.

Intensive Adoption as a Management Strategy for Unowned, Urban Cats: A Case Study of 25 Years of Trap-Assess-Resolve (TAR) in Auckland, New Zealand

Globally, unowned urban cats are a major concern because they may suffer from poor welfare and cause problems, including public health risks, nuisances, and urban wildlife predation. While management options are often presented as a choice between culling or trap−neuter−return (TNR), for 25 years, the Lonely Miaow (Inc.) charity in Auckland, New Zealand (hereafter LM), has used a third strategy—intensive adoption or trap−assess−resolve (TAR). As of 2019, of 14,611 unowned cats trapped, 64.2% were adopted, 22.2% were euthanized if unsocialised or in grave ill-health, 5.7% were neutered and returned to the site, and 7.9% had other outcomes, such as being transferred to other shelters. Adoption rates increased over this time, exceeding 80.0% in 2018 and 2019. The cost of processing each cat from capture to adoption rose from NZD 58 in 1999 to NZD 234 by 2017. Approximately 80% of colonies (sites where cats were trapped) were around residential areas. Approximately 22% of cats required veterinary treatment after capture; common ailments included respiratory infections, ringworm, dental problems, and trauma. Consistently, 52% of cats were young kittens (<10 weeks old), c. 80% of cats were <1 year old, and only c. 2% were estimated to be >5 years old. TAR avoids euthanasia where possible. Its effectiveness would be enhanced by fewer abandonments of owned cats and kittens, fitting within integrated strategies for the control of unowned cats involving community education. Cat adoptions improve the welfare of cats and, with appropriate husbandry, should alleviate concerns about nuisances, public health, and attacks on wildlife or the cats themselves, essentially benefitting the community and the cats. This case study is relevant to other cities around the world that are seeking to manage unowned cats.

Review and synthesis of the global literature on domestic cat impacts on wildlife

A vast global literature documents that free-roaming domestic cats (Felis catus) have substantial negative effects on wildlife, including through predation, fear, disease, and competition-related impacts that have contributed to numerous wildlife extinctions and population declines worldwide. However, no study has synthesized this literature on cat impacts on wildlife to evaluate its overarching biases and major gaps. To direct future research and conservation related to cat impacts on wildlife, we conducted a global literature review that entailed evaluation and synthesis of patterns and gaps in the literature related to the geographic context, methods, and types of impacts studied. Our systematic literature search compiled 2,245 publications. We extracted information from 332 of these meeting inclusion criteria designed to ensure the relevance of studies analyzed. This synthesis of research on cat impacts on wildlife highlights a focus on oceanic islands, Australia, Europe, and North America, and on rural areas, predation, impacts of unowned cats, and impacts at population and species levels. Key research advances needed to better understand and manage cat impacts include more studies in underrepresented, highly biodiverse regions (Africa, Asia, South America), on cat impacts other than predation, and on methods designed to reduce impacts on wildlife. The identified areas of needed research into cat impacts on wildlife will be critical to further clarifying the role of cats in global wildlife declines and to implementing science-driven policy and management that benefit conservation efforts.

Reduction of free-roaming cat population requires high-intensity neutering in spatial contiguity to mitigate compensatory effects

When free-roaming in natural areas, the domestic cat (Felis silvestris catus) is ranked high among the most destructive alien species. Near human dwellings, it might pose a risk to humans, impair sanitation, and suffer from poor welfare. Cats' popularity as companion animals complicates their population control. Thus, culling is often replaced by a fertility control method called “trap–neuter–return/release” (TNR), considered more humane. Despite the extensive application of TNR, a long-term controlled study was never performed to test its effectiveness. We present a uniquely designed controlled field experiment for examining TNR effectiveness. The study was performed over a 12-y period, divided into preintervention and mixed- and full-intervention phases, and spanned a 20-km2 urban area. Trends of cat, intact-female, and kitten counts, cat reproduction, and carcass reports were compared among study phases and areas with different neutering intensities. The cat population increased during the first two study phases and did not decline in highly neutered populations, presumably due to cat immigration. Expansion of high-intensity neutering to the entire city in the full-intervention phase (>70% neutering percentage) reversed cat population growth, reaching an annual approximately 7% reduction. This population reduction was limited by a rebound increase in cat reproduction and longevity. We conclude that cat population management by TNR should be performed with high intensity, continuously, and in geographic contiguity to enable population reduction. To enhance management effectiveness and mitigate compensatory effects, we recommend further evaluating an integrated strategy that combines TNR with complementary methods (e.g., vital resource regulation, ill cat euthanasia, and adoption).

Surviving the Urban Jungle: Anthropogenic Threats, Wildlife-Conflicts, and Management Recommendations for African Crowned Eagles

Larger carnivores often trigger human-wildlife conflicts that arise from perceived threats to humans and domestic animals’ safety, which generate the need for management and removal strategies. These issues become especially challenging when humans and wildlife coexist close to one another, for example, in urban landscapes. African Crowned Eagles (Stephanoaetus coronatus) are powerful forest raptors that breed within the metropolitan green-space system of Durban and Pietermaritzburg, South Africa. Negative human-wildlife interactions can occur because eagles occasionally predate on pets, such as cats (Felis catus) and small dogs (Canis lupus familiaris), and provisioning domestic stock to nest sites has previously been quantified. Here, wildlife management becomes critical, usually aimed at reducing or eliminating causes of economic or social harm, but have to be balanced against conservation goals regarding threatened species. In this study, we (i) identified causes of harm or loss of Crowned Eagles because of injuries (n = 53 incidents; 31 mortalities); and (ii) describe interactions with negative perceptions to human livelihoods, particularly concerning predation on pets and livestock. Anthropogenic causes of mortality were more likely to be reported than remote natural deaths, which provides important opportunities for mitigation measures. Most avoidable are electrocution on utility poles, persecution via gunshot wounds and poisoning (targeted or secondary), while collisions with anthropogenic structures, such as glass panes, vehicles and fence wires, are more challenging to mitigate. Out of 44 verified Crowned Eagle vs. pets and livestock conflicts, we documented 19 dog attacks (2012–2020), with detrimental impacts on social perception and acceptance of urban eagles. Pet and livestock conflicts were primarily associated with juveniles and immature eagles (83%). Of these, 19% occurred during September alone, which marks the end of the post-fledging dependency period; 70% occurred outside the breeding season. We provide management recommendations regarding various categories of Crowned Eagle human-wildlife interactions. For example, activities such as rehabilitation and falconry can coordinate to achieve a high standard of public support and conservation outcomes for Crowned Eagles. Finally, we discuss using different management intervention strategies, including rehabilitation, falconry, re-wildling processes, and lethal control of specific “problem” individuals toward achieving the goal of sustainable, healthy Crowned Eagle populations that coexist with humans in urban landscapes.

Use of molecular scatology to assess the diet of feral cats living in urban colonies

The overpopulation of domestic cats (Felis catus) presents a serious concern for wildlife conservationists, animal welfare advocates, public health officials, and community members alike. In cities, free-ranging, unowned cats often form high-density groups (commonly called ‘colonies’) around human provisioned food sources. While previous diet studies have primarily utilized morphology-based methods, molecular techniques offer a higher resolution alternative. In this study, we used next-generation sequencing techniques to examine the diet composition of feral cats living in five Trap-Neuter-Return colonies located in urban parks on Staten Island, a borough of New York City. We hypothesized that (1) cats living in urban colonies would still consume natural prey despite being regularly fed and (2) that the composition of taxa represented in the diet of each colony would vary, possibly due to differences in prey availability across sites. In total, 16 vertebrate prey taxa were identified in the diet, 13 at the genus level and 3 at the family level. Despite being regularly fed, 58.2% of cat scats contained DNA from natural prey. The diet composition of the cat colonies differed depending on the land cover composition surrounding the colony with the frequency of native prey positively correlated with the proportion of green space and that of non-native prey with developed land cover types. The use of molecular techniques combined with environmental DNA methods offers a promising, non-invasive approach to assessing the diet and consequently, impact of a highly abundant and non-native predator on the persistence of wildlife communities in cities.

Habitat use by wandering pet cats (Felis catus) in a patchy urban environment

Pet cats (Felis catus) often have negative effects on wildlife. This is of growing concern in urban areas as these are increasingly becoming hotspots of native wildlife activity, and as the human population increases, so too does the pet cat population. To maintain biodiversity in urban areas, further knowledge on pet cat behaviour and impacts is required so that management strategies for pet cats are well informed and have public and government support. Here, we offer insights into the wandering activity of pet cats in a patchy urban—heavily vegetated landscape on the east coast of Australia. Our estimated pet cat movement ranges were generally larger than those previously observed in similar landscapes, as well as in more urbanized and rural habitats. Using GPS data loggers, we found that pet cats did not utilize vegetated spaces more than urban areas, nor did they prefer them relative to their availability. Half of our study cats selected urban habitats, whilst the other half displayed no selection or a slight preference for vegetated spaces; these cats had fewer barriers to overcome to reach them. We did not observe any large differences in movements or habitat use between day and night, but displacement distances and preference for vegetated space habitat were marginally lower at night. All pet cats monitored spent most of their time outside their houses. As both urban and vegetated spaces in patchy urban landscapes provide habitat for native wildlife, pet cat activity across both habitat types requires management action.

Holistic understanding of contemporary ecosystems requires integration of data on domesticated, captive and cultivated organisms

Domestic and captive animals and cultivated plants should be recognised as integral components in contemporary ecosystems. They interact with wild organisms through such mechanisms as hybridization, predation, herbivory, competition and disease transmission and, in many cases, define ecosystem properties. Nevertheless, it is widespread practice for data on domestic, captive and cultivated organisms to be excluded from biodiversity repositories, such as natural history collections. Furthermore, there is a lack of integration of data collected about biodiversity in disciplines, such as agriculture, veterinary science, epidemiology and invasion science. Discipline-specific data are often intentionally excluded from integrative databases in order to maintain the “purity” of data on natural processes. Rather than being beneficial, we argue that this practise of data exclusivity greatly limits the utility of discipline-specific data for applications ranging from agricultural pest management to invasion biology, infectious disease prevention and community ecology. This problem can be resolved by data providers using standards to indicate whether the observed organism is of wild or domestic origin and by integrating their data with other biodiversity data (e.g. in the Global Biodiversity Information Facility). Doing so will enable efforts to integrate the full panorama of biodiversity knowledge across related disciplines to tackle pressing societal questions.

The Role of Carrion in the Landscapes of Fear and Disgust: A Review and Prospects

Animal behavior is greatly shaped by the ‘landscape of fear’, induced by predation risk, and the equivalent ‘landscape of disgust’, induced by parasitism or infection risk. However, the role that carrion may play in these landscapes of peril has been largely overlooked. Here, we aim to emphasize that animal carcasses likely represent ubiquitous hotspots for both predation and infection risk, thus being an outstanding paradigm of how predation and parasitism pressures can concur in space and time. By conducting a literature review, we highlight the manifold inter- and intra-specific interactions linked to carrion via predation and parasitism risks, which may affect not only scavengers, but also non-scavengers. However, we identified major knowledge gaps, as reviewed articles were highly biased towards fear, terrestrial environments, vertebrates, and behavioral responses. Based on the reviewed literature, we provide a conceptual framework on the main fear- and disgust-based interaction pathways associated with carrion resources. This framework may be used to formulate predictions about how the landscape of fear and disgust around carcasses might influence animals’ individual behavior and ecological processes, from population to ecosystem functioning. We encourage ecologists, evolutionary biologists, epidemiologists, forensic scientists, and conservation biologists to explore the promising research avenues associated with the scary and disgusting facets of carrion. Acknowledging the multiple trophic and non-trophic interactions among dead and live animals, including both herbivores and carnivores, will notably improve our understanding of the overlapping pressures that shape the landscape of fear and disgust.

Beloved Whiskers: Management Type, Care Practices and Connections to Welfare in Domestic Cats

Simple Summary

Little is known about the differences between indoor and outdoor cat management practices. Thus, our study investigated whether Brazilian cat owners’ management types were related to other cat care practices, the quality of human-animal interactions and cat welfare. We used social networks to distribute an online survey to cat owners. This survey included questions regarding owners’ sociodemographic data, type of management applied, cat care practices, and cat health and behavioral problems, as possible consequences of the management type. A total of 16,302 cat owners responded. Most (74.78%) owners reported providing indoor management for their cats; this corresponded to owners who lived in apartments and provided more cat care practices and interactions with their pets. Outdoor management was related to cats residing in farms or houses, sleeping outdoors, and having less interaction with their owners. We concluded that owners practicing indoor management were more likely to be closer to their cats than those reporting outdoor management, suggesting that the former may have more advantages related to closer human-animal relationships. It was noted, however, that indoor management was associated with obesity and owner-reported behavioral problems.

Abstract

The quality of cat care practices depends in part on the type of management applied, which either positively or negatively impacts cat welfare. This study investigated whether the type of cat management (indoor vs. outdoor) was related to other cat care practices adopted by cat owners, associated with the quality of human-cat relationships and cat welfare. An online survey was distributed via social networks. Descriptive statistics, categorical Principal Component Analysis, Fisher’s Exact test and Chi-square test in contingency table were applied. A total of 16,302 cat owners returned the survey. Most Brazilian owners reported indoor management of their cats; this was related to owners living in apartments, more frequent use of cat care practices, and more interactions with their pets. Outdoor management was related to cats living in houses or farms, sleeping outdoors or around the neighborhood, and owners had fewer interaction with their pets. In conclusion, owners practicing indoor management seemed to be closer to their cats than owners reporting outdoor management. However, obesity and owner-reported behavioral problems were associated with indoor management.

Development of the Mata Hari Judas Queen (Felis catus)

Cats (Felis catus) are significant predators of mammals, birds, frogs and reptiles and are implicated in mammal species extinctions in Australia. Current controls fail to eradicate entire populations allowing survivors to re-establish. The use of the Mata Hari Judas (MHJ) technique, i.e., inducing prolonged oestrus using hormone implants, can enhance the eradication of remnant animals and would greatly improve conservation efforts. The hypotheses tested were that hormone implants could induce prolonged oestrus in queens (adult female cats), and that prolonging oestrus would result in sustained attractiveness to toms (adult male cats). Queens (n = 14) were randomly allocated to five treatments including a control and four treatments using hormone implants. Queens were observed daily; alone and during indirect contact with a tom for 30 consecutive days. There were significant increases (p < 0.001) in oestrus duration (19 to 27 days) for entire and ovariohysterectomised queens given Compudose100™ implants (1/8 or 1/4 implant). This study shows that it is possible to induce and prolong oestrus in queens using Compudose100™ implants where these queens are attractive to toms. The MHJ queen is a new tool with the potential to enhance the detection and thus the control of feral cats in remnant populations.

Reply to Wolf et al.: Why Trap-Neuter-Return (TNR) Is Not an Ethical Solution for Stray Cat Management

Simple Summary

We provide a rebuttal to Wolf et al. (2019), outlining biological, ethical, and economic flaws in their argument that Trap-Neuter-Return (TNR) is an ethical solution for stray cat management. We contend that suppression of supplementary feeding of stray cats accompanied by proactive adoption or prompt euthanasia is more effective, humane, and economical.

Abstract

We critique the recent article by Wolf et al. (2019) that claims scientific merit for reducing the number of stray cats in Australia through Trap-Neuter-Return (TNR) programs, and then we provide an inventory of biological, welfare, and economic reasons why TNR is less successful than adoption and euthanasia for managing unowned cats. Like Crawford et al. (2019) and multiple other comprehensive and unbiased Australian and international scientific reviews, we refute the idea that returning neutered unowned cats to stray populations has any valid role in responsible, ethical, affordable, and effective cat management, or in wildlife conservation. The main purported objective of TNR proponents along with animal welfare, human health, and wildlife advocacy stakeholders is to reduce the number of unhomed cats. We contend that cessation of provisioning unowned cats with food is the most effective approach to achieve this objective. We also present evidence from the Brisbane City Council that informed cat management policy, advocacy, and laws, backed up by responsible rehoming or prompt ethical euthanasia, are together effective at reducing the stray cat problem.

Analysis of cat diet across an urbanisation gradient

The domestic cat is a widespread and abundant predator that negatively impacts a wide range of species. However, the predation activity and prey type of free-ranging cats may vary between areas with different levels urbanisation. Previous analyses of cat diet have used differing techniques to measure predation that often differ with one another. Given the variability in these methods we hypothesised that cats in rural areas will have a more diverse diet than in urban areas and their predation rate may be higher than those in the urban sites. Moreover, we hypothesized that the diet of urban cats should be highly influenced by anthropogenic food. We selected sites across a rural-to-urban gradient and used three methods of analysis to determine prey in the diet (cat stomachs, cat scats, and prey brought home). We collected 81 stomachs, 409 scats, and 337 prey items of free-roaming cats from six study sites located in southern and eastern Poland. We found seasonal and habitat related differences in prey composition. The proportion of scats and stomachs containing vertebrate varied from 17% in urban areas to 79% in one of the rural areas. Small rodents were the dominant prey category, followed by birds and soricomorphs. Anthropogenic food was found to be an important part of urban cats’ diet, but its significance decreased with a decrease in urbanisation level. Both predation rate and prey diversity were highest in rural areas. While diet analysis provided a better estimation of cat predation rate, the detailed prey examination provided better insight into less common taxa killed by the cats, such as reptiles and small mustelids. Our results contribute to the discussion about the risks associated with the activity of free ranging cats especially in areas with high conservation values.

Evidence for Citation Networks in Studies of Free-Roaming Cats: A Case Study Using Literature on Trap-Neuter-Return (TNR)

Simple Summary

All aspects of an argument need to be evaluated in evidence-based scientific pursuit to prevent the development of self-reinforcing cohorts of studies through the cross-referencing of selected subsets of studies (citation bias). Controling populations of unowned cats using Trap–Neuter–Return and its variants (hereafter TNR) is an example of how a scientific topic develops and is communicated academically and publicly. We found 145 TNR publications between 2002–2019, with the last two years seeing a rapid increase in studies. Publication clusters occur, focusing on: population control, interactions with wildlife, disease transmission (including implications for pet cats, wildlife and humans), free-roaming cats, and feral and domestic cat management. A quarter of all studies were published in Open Access formats, which have the highest potential social impact because they are free to download, share and read. While it is encouraging that diverse views are expressed, the development of clusters of introspective topics risks reduced dialogue between groups of authors with differing views. Journal editors could encourage exchanges between groups by choosing reviewers from different camps to assess manuscripts and by asking authors to acknowledge alternative views.

Abstract

Trap–Neuter–Return and its variants (hereafter TNR) aims to control unowned cat populations. Papers on this topic form a useful case study of how how an area of literature grows, papers become influential, and citation networks form, influencing future study as well as public perceptions of the science. We analysed 145 TNR studies published 2002–2019. Common topics, identified by frequently used language, were population control, interactions with wildlife, disease transmission (including implications for pets, wildlife and humans), free-roaming cats, and feral and domestic cat management. One or more papers on each of these topics was judged influential because of high citations overall, high average citations/year, or frequent mentions in social media. Open Access papers were more influential in social media, raising greater public awareness than studies published in journals that were less accessible. While divergent views exist on a range of topics, the network analysis of the TNR literature indicated potential for forming self-reinforcing groups of authors. While it is encouraging that diverse views are expressed, there is a risk of reduced dialogue interactions between groups, potentially constraining dialogue to refine arguments, share information, or plan research. Journal editors could encourage communication by choosing reviewers from different camps to assess manuscripts and by asking authors to acknowledge alternative views.

Uncontrolled Outdoor Access for Cats: An Assessment of Risks and Benefits

Uncontrolled outdoor access is associated with a number of welfare concerns for companion cats, including increased risks of disease and parasites, injury or death due to traffic, predation or ingestion of toxic substances, and getting permanently separated from their owner. In addition, cats pose a threat to local wildlife due to predatory behaviors, and can sometimes be a nuisance to human neighbors. Despite these concerns, recent estimates suggest that many owners are still providing their cats with uncontrolled outdoor access, likely because it also offers welfare benefits by allowing cats to perform natural behaviors, such as hunting, exploring, and climbing. While some have suggested that outdoor access is necessary to meet cats' behavioral needs and to prevent related behavioral problems, others have recommended various environmental enrichment strategies that can be developed to meet these needs within an indoor environment or through supervised and controlled outdoor access. This review examines the welfare issues and benefits associated with outdoor access for cats, as well as what is currently known about peoples' practices, knowledge, and attitudes about the provision of outdoor access for cats.

Cat-dependent diseases cost Australia AU$6 billion per year through impacts on human health and livestock production

Abstract ContextCats are the definitive or primary host for pathogens that cause diseases in people and livestock. These cat-dependent diseases would not occur in Australia if cats had not been introduced, and their ongoing persistence depends on contacts with cats. Toxoplasma gondii is a protozoan parasite that cycles between cats and any other warm-blooded animals. People infected by T. gondii may appear asymptomatic, or have a mild illness, or experience severe, potentially lethal symptoms; the parasite may also affect behaviour and mental health. T. gondii is also a major contributor to spontaneous abortion in sheep and goats. Two species of Sarcocystis, another genus of protozoan parasite, cycle through cats and sheep, causing macroscopic cysts to form in sheep tissues that reduce meat saleability. Toxocara cati, the cat roundworm, causes minor illnesses in humans and livestock, and the bacterium Bartonella henselae causes cat scratch disease, an infection that can be contracted by people when scratched or bitten by cats carrying the pathogen. AimsWe estimated the economic costs of cat-dependent pathogens in Australia. MethodsWe collated national and global data on infection rates, health and production consequences. Key resultsWe estimated the costs of two cat-dependent diseases (toxoplasmosis, cat scratch disease) in people at AU$6.06 billion (plausible range AU$2.11–10.7 billion) annually, and the costs to livestock production from toxoplasmosis and sarcocystosis at AU$11.7 million (plausible range AU$7.67–18.3 million). Most of the human health costs are due to the associations between T. gondii and higher rates of traffic accidents and mental illness in people. The causality behind these associations remains uncertain, so those costs may be overestimated. Conversely, our estimates are incomplete, infections and illness are under-reported or misdiagnosed, and our understanding of disease outcomes is still imperfect, all of which make our costs underestimated. ConclusionsOur analysis suggests that substantial benefits to public health and livestock production could be realised by reducing exposure to cats and breaking parasite transmission cycles. ImplicationsReducing feral cat populations in farming and urban areas, reducing the pet cat population and increasing rates of pet cat containment could help reduce the burden of cat-dependent diseases to people and livestock.

Who let the cats out? A global meta-analysis on risk of parasitic infection in indoor versus outdoor domestic cats ( Felis catus)

Parasitic infection risks in domestic animals may increase as a result of outdoor activities, often leading to transmission events to and from owners, other domestic animals and wildlife. Furthermore, outdoor access has not been quantified in domestic animals as a risk factor with respect to latitude or parasite transmission pathway. Cats are an ideal model to test parasitic infection risk in outdoor animals because there have been many studies analysing this risk factor in this species; and there is a useful dichotomy in cat ownership between indoor-only cats and those with outdoor access. Thus, we used meta-analysis to determine whether outdoor access is a significant risk factor for parasitic infection in domestic pet cats across 19 different pathogens including many relevant to human, domestic animal and wildlife health, such as Toxoplasma gondii and Toxocara cati. Cats with outdoor access were 2.77 times more likely to be infected with parasites than indoor-only cats. Furthermore, absolute latitude trended towards significance such that each degree increase in absolute latitude increased infection likelihood by 4%. Thus, restricting outdoor access can reduce the risk of parasitic infection in cats and reduce the risk of zoonotic parasite transmission, spillover to sympatric wildlife and negative impacts on feline health.

A Case of Letting the Cat out of The Bag-Why Trap-Neuter-Return Is Not an Ethical Solution for Stray Cat (Felis catus) Management

Trap-Neuter-Return (TNR) programs, in which stray cats are captured, neutered and returned to the environment are advocated as a humane, ethical alternative to euthanasia. We review the TNR literature in light of current debate over whether or not there should be further TNR trials in Australia. We revisit the problems arising from stray cats living in association with human habitation and estimate how many stray cats would have to be processed through a scientifically-guided TNR program to avoid high euthanasia rates. We also identify 10 ethical and welfare challenges that have to be addressed: we consider the quality of life for stray cats, where they would live, whether the TNR process itself is stressful, whether TNR cats are vulnerable to injury, parasites and disease, can be medically treated, stray cats' body condition and diet, and their impacts on people, pet cats, and urban wildlife, especially endemic fauna. We conclude that TNR is unsuitable for Australia in almost all situations because it is unlikely to resolve problems caused by stray cats or meet ethical and welfare challenges. Targeted adoption, early-age desexing, community education initiatives and responsible pet ownership have greater promise to minimize euthanasia, reduce numbers rapidly, and address the identified issues.

Management of Pet Cats: The Impact of the Cat Tracker Citizen Science Project in South Australia

Simple Summary

Domestic cats are popular pets worldwide and play an important role in the lives of many of their owners; however, there is growing awareness of the potential negative impacts of cats. The Cat Tracker citizen science project was conducted in South Australia to better understand domestic cats, their movement, and related community views. The project was deliberately designed to engage cat owners and assist them to make informed decisions about the management of their pet cats. The project collected data through an online social survey and tracking of pet cats, using small GPS units. This study evaluates the project and examines its impact on participant knowledge, attitude, and behaviour. We found that participation in the tracking activity had positive learning outcomes for cat owners and that, after participating, many cat owners placed an increased level of importance on containing cats. Participants reported that they changed their behaviour with existing pet cats and reported intentions to change behaviour with future pet cats. We discuss positive impacts on other members of the community, and how negative impacts may be avoided. We advocate for further research in this area to understand how projects can drive positive changes in knowledge, attitudes, and behaviours.

Abstract

Domestic cats (Felis catus) are popular pets worldwide and play an important role in the lives of many of their owners; however, there is growing awareness of the potential negative impacts of cats. Accordingly, there is increasing interest in pet cat management, including changing the attitudes and behaviours of cat owners. The Cat Tracker citizen science project was conducted in South Australia to better understand domestic cats, their movement, and related community views. The project was deliberately designed to engage cat owners and assist them to make informed decisions about the management of their pet cats. The project collected data through an online social survey (n = 3192) and GPS tracking of pet cats (n = 428), conducted between February 2015 and September 2016. A public report was published in February 2017 and an evaluation survey (n = 410) was conducted between March and May 2017. This study evaluates the project and examines its impact on participant knowledge, attitude, and behaviour. We found that participation in the tracking activity had a statistically significant influence on participant-reported learning. For participant cat owners, we recorded statistically significant increases in the level of importance placed on containing cats (both during the day and at night). Participants reported that they changed their behaviour with existing pet cats and reported intentions to change behaviour with future pet cats. We discuss impacts beyond what we set out to measure, including impacts on project onlookers, profound impacts on participants, and how the rebound effect (which can generate negative impacts) may be avoided. We describe social science applied to citizen science and advocate for further research in this area to understand how projects can drive positive changes in knowledge, attitudes, and behaviours.

Disentangling the link between supplemental feeding, population density, and the prevalence of pathogens in urban stray cats

BACKGROUND

Supplemental feeding of free-roaming animals, including wildlife and feral or stray animals, is well known to have a substantial impact on various aspects of animal ecology including habitat use, activity patterns, and host-pathogen interactions. Among them, an increased population density (PD) of animals receiving supplemental food raises concerns regarding the transmission of pathogens in these host populations. The primary aim of this study was to investigate how supplemental feeding is associated with host PD and prevalence of pathogens with different transmission modes in urban stray cats. We hypothesized that supplemental feeding would be positively associated with host PD and the prevalence of pathogens with density-dependent transmission modes compared with pathogens with transmission modes that are considered relatively density-independent.

METHODS

This study was conducted in six districts in Seoul, Republic of Korea which were selected based on different degrees of supplemental feeding and cat caretaker activity (CCA). The PD of stray cats was estimated by mark-recapture surveys. Stray cat blood samples (N = 302) were collected from stray cats by local animal hospitals from each district performing the trap-neuter-release which tested for eight pathogens with different transmission modes (feline immunodeficiency virus, feline leukemia virus (FeLV), feline panleukopenia virus, feline calicivirus, feline herpesvirus-1, Bartonella henselae, hemoplasma, and Toxoplasma gondii) with molecular or serological assays. Associations between the prevalence of each pathogen and PD, CCA, and sex of cats were statistically analyzed.

RESULTS

In contrast to initial predictions, the cat PD was generally higher in low CCA districts. The prevalence of (FeLV), which is transmitted through direct contact, was significantly higher in areas with a high CCA, conforming to our hypothesis. On the other hand, the prevalence of feline parvovirus, which can be spread by environmental transmission, was higher in low CCA districts. The remaining six pathogens did not show any association with the CCA; however, they had a unique association with the PD or the sex of the stray cats.

DISCUSSION

Our findings suggest that in addition to influencing the PD, supplemental feeding may affect the prevalence of pathogens in urban animals by mechanisms such as increased aggregation and/or altered foraging strategies, with different consequences depending on the transmission mode of each pathogen.

Hierarchical filters determine community assembly of urban species pools

The majority of humanity now lives in cities or towns, with this proportion expected to continue increasing for the foreseeable future. As novel ecosystems, urban areas offer an ideal opportunity to examine multi-scalar processes involved in community assembly as well as the role of human activities in modulating environmental drivers of biodiversity. Although ecologists have made great strides in recent decades at documenting ecological relationships in urban areas, much remains unknown, and we still need to identify the major ecological factors, aside from habitat loss, behind the persistence or extinction of species and guilds of species in cities. Given this paucity of knowledge, there is an immediate need to facilitate collaborative, interdisciplinary research on the patterns and drivers of biodiversity in cities at multiple spatial scales. In this review, we introduce a new conceptual framework for understanding the filtering processes that mold diversity of urban floras and faunas. We hypothesize that the following hierarchical series of filters influence species distributions in cities: (1) regional climatic and biogeographical factors; (2) human facilitation; (3) urban form and development history; (4) socioeconomic and cultural factors; and (5) species interactions. In addition to these filters, life history and functional traits of species are important in determining community assembly and act at multiple spatial scales. Using these filters as a conceptual framework can help frame future research needed to elucidate processes of community assembly in urban areas. Understanding how humans influence community structure and processes will aid in the management, design, and planning of our cities to best support biodiversity.

Research challenges and conservation implications for urban cat management in New Zealand

Over the past 20 years, conservation efforts in New Zealand have moved from being concentrated in rural and isolated island locations, where exotic mammalian predators are often controlled, to begin to bring native fauna back to major cities. However, human–wildlife conflicts arise when conservation occurs in close proximity to cities. These are particularly intense when companion animals are involved either as potential predators or prey of high-value conservation animals. Within New Zealand, this conflict is particularly fraught around domestic cats (Felis catus) in the urban environment. Cats in New Zealand are recognised as major introduced predators of native fauna, but they also prey on small introduced predatory mammals. This dynamic causes much conflict between people with different attitudes towards animals; however, as yet, few studies have explored the role(s), either negative or positive, of urban cats in New Zealand. Here, we review current knowledge on domestic cats in urban New Zealand, identify gaps in knowledge and make suggestions for future research, which includes further social science research, citizen science-based research programs, market research, investigation into cat-management legislation, and more in-depth studies of cat diseases and zoonoses. These data are vital for informing the public and improving the management of urban cat populations, including mitigating conservation impacts. Urban ecologists will need to be versatile in the way they design and conduct experiments, exploiting multiple disciplines to both ensure scientific robustness, but also community and government support for uptake of results into management and legislation.

Effects of Long-Term Exposure to an Electronic Containment System on the Behaviour and Welfare of Domestic Cats

Free-roaming cats are exposed to a variety of risks, including involvement in road traffic accidents. One way of mitigating these risks is to contain cats, for example using an electronic boundary fence system that delivers an electric ‘correction’ via a collar if a cat ignores a warning cue and attempts to cross the boundary. However, concerns have been expressed over the welfare impact of such systems. Our aim was to determine if long-term exposure to an electronic containment system was associated with reduced cat welfare. We compared 46 owned domestic cats: 23 cats that had been contained by an electronic containment system for more than 12 months (AF group); and 23 cats with no containment system that were able to roam more widely (C group). We assessed the cats’ behavioural responses and welfare via four behavioural tests (unfamiliar person test; novel object test; sudden noise test; cognitive bias test) and an owner questionnaire. In the unfamiliar person test, C group lip-licked more than the AF group, whilst the AF group looked at, explored and interacted more with the unfamiliar person than C group. In the novel object test, the AF group looked at and explored the object more than C group. No significant differences were found between AF and C groups for the sudden noise or cognitive bias tests. Regarding the questionnaire, C group owners thought their cats showed more irritable behaviour and AF owners thought that their cats toileted inappropriately more often than C owners. Overall, AF cats were less neophobic than C cats and there was no evidence of significant differences between the populations in general affective state. These findings indicate that an electronic boundary fence with clear pre-warning cues does not impair the long term quality of life of cats.