Predicting free-roaming cat population densities in urban areas

Home range size and habitat selection of owned outdoor domestic cats (Felis catus) in urban southwestern Ontario

Domestic cats (Felis catus) play a dual role in society as both companion animals and predators. When provided with unsupervised outdoor access, cats can negatively impact native wildlife and create public health and animal welfare challenges. The effective implementation of management strategies, such as buffer zones or curfews, requires an understanding of home range size, the factors that influence their movement, and the types of habitats they use. Here, we used a community/citizen scientist approach to collect movement and habitat use data using GPS collars on owned outdoor cats in the Kitchener-Waterloo-Cambridge-Guelph region, southwestern Ontario, Canada. Mean (± SD) 100% minimum convex polygon home range size was 8 ± 8 ha (range: 0.34-38 ha) and was positively associated with road density but not with intrinsic factors such as boldness, sex, or age. With regards to habitat selection, cats used greenspaces, roads, and agricultural land less often than predicted but strongly selected for impervious surfaces (urban areas other than greenspaces or roads). Our results suggest that wildlife near buildings and residential areas are likely at the greatest risk of cat predation and that a buffer size of 840 m would be needed to restrict cats from entering areas of conservation concern.

Challenges and opportunities in human dimensions behind cat-wildlife conflict

Because global anthropogenic activities cause vast biodiversity loss, human dimensions research is essential to forming management plans applicable to biodiversity conservation outside wilderness areas. Engaging public participation is crucial in this context to achieve social and environmental benefits. However, knowledge gaps remain in understanding how a balance between conservation and public demands can be reached and how complicated sociocultural contexts in the Anthropocene can be incorporated in conservation planning. We examined China's nationwide conflict between free-ranging cats (owned cats that are allowed to go outdoors or homeless cats living outdoors) and wildlife to examine how a consensus between compassion and biodiversity conservation can help in decision-making. We surveyed a random sample of people in China online. Over 9000 questionnaires were completed (44.2% response). In aggregate, respondents reported approximately 29 million free-ranging owned cats and that over 5 million domestic cats per year become feral in mainland China. Respondents who were cat owners, female, and religious were more likely to deny the negative impacts of cats on wildlife and ongoing management strategies and more supportive of stray cat shelters, adoption, and community-based fund raising than nonowners, male, and nonreligious respondents (p < 0.05). Free-ranging cat ownership and abandonment occurred less with owners with more knowledge of biodiversity and invasive species than with respondents with less knowledge of these subjects (p < 0.05). We recommend that cat enthusiasts and wildlife conservationists participate in community-based initiatives, such as campaigns to keep cats indoors. Our study provides a substantially useful framework for other regions where free-ranging cats are undergoing rapid expansion.

CATastrophic myths part 1: Common misconceptions about the social behavior of domestic cats and implications for their health, welfare, and management

Cats are among the most popular pets worldwide, but there are still major gaps in the public's general understanding of their social behaviors and related needs, including for socialization. In addition to these knowledge gaps, people often have negative or ambivalent attitudes about cats, which can directly impact their welfare outcomes. Insufficient attention to the behavioral ecology and development of cat sociality, along with failure to account for their highly variable individual preferences and tolerance for social behaviors can lead them to experience distress that undermines both their welfare and the human-animal bond. As Part 1 of a two-part series addressing common myths about cats, the purpose of this first paper is to review and debunk common misperceptions about the social needs and behaviors of cats, including misunderstandings about their social lives and abilities to bond with humans. We also identify where opportunities exist to improve socialization of cats and to advance research in related areas that might better support their behavior and welfare needs.

Spatial and Temporal Movements of Free-Roaming Cats and Wildlife in Two Local Government Areas in Greater Sydney, Australia

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.

Counting the Capital's cats: Estimating drivers of abundance of free-roaming cats with a novel hierarchical model

Free-roaming cats are a conservation concern in many areas but identifying their impacts and developing mitigation strategies requires a robust understanding of their distribution and density patterns. Urban and residential areas may be especially relevant in this process because free-roaming cats are abundant in these anthropogenic landscapes. Here, we estimate the occupancy and density of free-roaming cats in Washington D.C. and relate these metrics to known landscape and social factors. We conducted an extended camera trap survey of public and private spaces across D.C. and analyzed data collected from 1483 camera deployments from 2018 to 2020. We estimated citywide cat distribution by fitting hierarchical occupancy models and further estimated cat abundance using a novel random thinning spatial capture-recapture model that allows for the use of photos that can and cannot be identified to individual. Within this model, we utilized individual covariates that provided identity exclusions between photos of unidentifiable cats with inconsistent coat patterns, thus increasing the precision of abundance estimates. This combined model also allowed for unbiased estimation of density when animals cannot be identified to individual at the same rate as for free-roaming cats whose identifiability depended on their coat characteristics. Cat occupancy and abundance declined with increasing distance from residential areas, an effect that was more pronounced in wealthier neighborhoods. There was noteworthy absence of cats detected in larger public spaces and forests. Realized densities ranged from 0.02 to 1.75 cats/ha in sampled areas, resulting in a district-wide estimate of ~7296 free-roaming cats. Ninety percent of cat detections lacked collars and nearly 35% of known individuals were ear-tipped, indicative of district Trap-Neuter-Return (TNR) programs. These results suggest that we mainly sampled and estimated the unowned cat subpopulation, such that indoor/outdoor housecats were not well represented. The precise estimation of cat population densities is difficult due to the varied behavior of subpopulations within free-roaming cat populations (housecats, stray and feral cats), but our methods provide a first step in establishing citywide baselines to inform data-driven management plans for free-roaming cats in urban environments.

Stable isotopes unveil one millennium of domestic cat paleoecology in Europe

The domestic cat is the world's most popular pet and one of the most detrimental predators in terrestrial ecosystems. Effective protection of wildlife biodiversity demands detailed tracking of cat trophic ecology, and stable isotopes serve as a powerful proxy in dietary studies. However, a variable diet can make an isotopic pattern unreadable in opportunistic predators. To evaluate the usefulness of the isotopic method in cat ecology, we measured C and N isotope ratios in hundreds of archaeological cat bones. We determined trends in cat trophic paleoecology in northern Europe by exploiting population-scale patterns in animals from diverse locations. Our dataset shows a high variability of isotopic signals related to the socio-economic and/or geomorphological context. This points toward regularities in isotopic patterns across past cat populations. We provide a generalized guide to interpret the isotopic ecology of cats, emphasizing that regional isotopic baselines have a major impact on the isotopic signal.

Direct and Indirect Factors Influencing Cat Outcomes at an Animal Shelter

Animal shelters play a vital role for pets, such as transitioning animals between homes, from outdoor communities into homes, caring for unadoptable and community animals, and providing a breadth of veterinary and welfare services. The goal of shelters is to move cats to their appropriate outcome as quickly as possible, which for many animals, is to rehome them as quickly as possible through adoption. Therefore, the ability to identify pre-existing factors, particularly those occurring outside the walls of the shelter, which result in specific outcomes is vital. In this study, we used structural equation modeling to test four hypotheses addressing how to predict cat outcome from a shelter in Washington, D.C. We developed four hypotheses that described how cat outcomes could be predicted, based on four general factors: (1) The characteristics of the cats; (2) The location of origin; (3) The type and date of intake; (4) The length of stay. Using 4 years of data from the Humane Rescue Alliance in Washington, D.C., we found support for each of our hypotheses. Additionally, we tested and found support for a global model, which comprised an amalgamation of our all our predictors. From the global model, we can conclude that many factors are at play in predicting cat outcomes in this shelter and very likely in many others as well. Critically, these factors are interconnected, indicating, for example, that cat characteristics mediate the influence of intake location on outcome type. Furthermore, our study highlights the importance of incorporating influences beyond the shelter when attempting to understand cat outcomes. Therefore, to modify cat outcomes most efficiently, such as increasing adoption probabilities, our results show that efforts may be most effective when incorporating multiple factors.

Human influences shape the first spatially explicit national estimate of urban unowned cat abundance

Globally, unowned cats are a common element of urban landscapes, and the focus of diverse fields of study due to welfare, conservation and public health concerns. However, their abundance and distribution are poorly understood at large spatial scales. Here, we use an Integrated Abundance Model to counter biases that are inherent in public records of unowned cat sightings to assess important drivers of their abundance from 162 sites across five urban towns and cities in England. We demonstrate that deprivation indices and human population densities contribute to the number of unowned cats. We provide the first spatially explicit estimates of expected distributions and abundance of unowned cats across a national scale and estimate the total UK urban unowned cat population to be 247,429 (95% credible interval: 157,153 to 365,793). Our results provide a new baseline and approach for studies on unowned cats and links to the importance of human-mediated effects.

Domestic Cat Abundance and Activity Across a Residential Land Use Gradient

Free-ranging domestic cats are a detriment to wildlife and humans by preying on native species and transmitting disease. As a result, removing free-ranging cats from the landscape has become a conservation and public health priority. Estimating cat population size with an unbiased sampling design, however, especially in human-dominated areas, is logistically challenging and rarely done. The lack of robust cat population sampling limits our understanding of where cats pose risks, which is important for evaluating management strategies, such as trap-remove or trap-neuter-return. We hypothesized that cat abundance and activity both depend on human land use and demographics. Using a network of sites participating in a community science program, we conducted transect and camera trap surveys to test predictions of cat population abundance and activity across a gradient of residential land use intensity. Both sampling methods determined that cat abundance was greatest in areas with intermediate human population density and lower educational attainment. Transect data also provided evidence that cat abundance was greatest at intermediate levels of impervious surface cover (e.g., road and buildings), while data from camera traps also showed that cat abundance was positively associated with household income. Using counts of cats observed on cameras, we found that the timing of cat activity varied depending on the degree of urban intensity. Cats were more strictly nocturnal in medium and high intensity residential land-use areas, possibly because a greater proportion of these cats are unowned or because they avoid human activity. These results suggest that transect surveys conducted during the day may undercount cats in urban environments where unowned free-ranging cats predominate. Taken together, our results highlight the importance of incorporating human demographics, land use patterns, and urban context in estimating the abundance of free-ranging cats to better inform management decisions and improve conservation outcomes.

Counting Cats: The integration of expert and citizen science data for unbiased inference of population abundance

Free-roaming animal populations are hard to count, and professional experts are a limited resource. There is vast untapped potential in the data collected by nonprofessional scientists who volunteer their time to population monitoring, but citizen science (CS) raises concerns around data quality and biases. A particular concern in abundance modeling is the presence of false positives that can occur due to misidentification of nontarget species. Here, we introduce Integrated Abundance Models (IAMs) that integrate citizen and expert data to allow robust inference of population abundance meanwhile accounting for biases caused by misidentification. We used simulation experiments to confirm that IAMs successfully remove the inflation of abundance estimates caused by false-positive detections and can provide accurate estimates of both bias and abundance. We illustrate the approach with a case study on unowned domestic cats, which are commonly confused with owned, and infer their abundance by analyzing a combination of CS data and expert data. Our case study finds that relying on CS data alone, either through simple summation or via traditional modeling approaches, can vastly inflate abundance estimates. IAMs provide an adaptable framework, increasing the opportunity for further development of the approach, tailoring to specific systems and robust use of CS data.

Public opinions on seven different stray cat population management scenarios in Flanders, Belgium

Stray cat population management is an important worldwide issue. Understanding citizen attitudes towards stray cat control options is vital to the success of controlling stray cat numbers, as public perception affects the acceptance of, support for and collaboration in stray cat management policies. Audience segmentation, as to enable each group to be engaged in the stray cat management policy, is important for the success of the interventions. Therefore a web-based survey was conducted among Flemish citizens in order to examine differences in acceptance towards seven management scenarios: household cat neutering with financial support for the owner, household cat neutering without financial support for the owner, encouraging responsible household cat ownership, trapping stray cats and taking them to a shelter, trapping and neutering stray cats for release into a managed "cat colony" (composed by so called "community cats"), trapping and killing of stray cats, and undertaking no action. A total of 4059 valid responses were collected and the proportions of agreement were compared across the different management scenarios using the two-sample z-test. Interactions among factors that influenced each management scenario were investigated using the CHAID (Chi-squared Automatic Interaction Detection) analysis and visualized on a tree. Our results showed that fostering responsible household cat ownership (89.9%) and conversion of stray cats to "community cats" (76.3%) were most supported by respondents in our sample (which consisted mainly of females, cat-lovers, and families without children). Least supported were the killing of stray cats (7.7%) and undertaking no action (3.3%). The demographic analyses revealed that for the acceptance of management scenarios there were three important factors (attitude towards cats, area of residence, and gender), two weaker factors (education and having children) and two which had almost no impact (age and cat ownership). We propose that future studies should focus on the effect of 'area of residence', 'having children' and 'education'. In conclusion, our research confirms that management of and communication on stray cat strategies should not be developed with a one-size-fits-all approach. Efforts should be tailored to each audience segment, thus adapted to the area of residence and human characteristics.

Are physiological and behavioural responses to stressors displayed concordantly by wild urban rodents?

Understanding wild animal responses to stressors underpins effective wildlife management. In order for responses to stressors to be correctly interpreted, it is critical that measurements are taken on wild animals using minimally invasive techniques. Studies investigating wild animal responses to stressors often measure either a single physiological or behavioural variable, but whether such responses are comparable and concordant remains uncertain. We investigated this question in a pilot study that measured responses of wild-caught urban brown and black rats (Rattus norvegicus, Rattus rattus) to fur-based olfactory cues from a predator, the domestic cat (Felis catus); a novel herbivore, the koala (Phascolarctos cinereus); and a familiar herbivore and competitor, the common brushtail possum (Trichosurus vulpecula). Physiological responses, measured by assaying faecal glucocorticoid metabolites, were compared to behavioural responses observed via video recordings. We found that physiological and behavioural responses to stressors were expressed concordantly. There was no sizeable physiological response observed, and the behavioural response when considered across the night was negligible. However, the behavioural response to the predator and competitor cues changed across the observation period, with activity increasing with increasing hours of exposure. Our results indicate that responses of wild rodents to cues are nuanced, with stress responses modulated by behaviour changes that vary over time according to the severity of the perceived threat as animals gather further information. If the physiological response alone had been assessed, this moderated response may not have been evident, and in terms of wildlife management, vital information would have been lost.

Identification of the population source of free-ranging cats threatening endemic species on Tokunoshima Island, Japan

Free-ranging cats Felis silvestris catus are harmful to endemic species, especially on islands. Effective management practices require an understanding of their habitat use and population source at the landscape level. We aimed to identify the source of the free-ranging cat population on Tokunoshima Island, Japan, which harbors a variety of endemic organisms as well as human settlements. Trapping data for the whole island were provided by local governments, and landscape factors (residential, agricultural, and woodlot areas and cattle barn density) affecting cat density were explored. An analysis of live-capture data indicated that the density (per 1 km2) of free-ranging cats was positively correlated with the densities of cattle barns and woodlot areas and negatively correlated with residential areas. An interview survey revealed that nearly half of the cattle barns feed free-ranging cats. The source habitat of free-ranging cats appears to be areas with a high density of cattle barns and a high percentage of woodlots in human-dominated landscapes. Feeding cats in cattle barns may strengthen the bottom-up process of population growth on the island. To reduce the impact of cats on endemic species on Tokunoshima Island, efforts to stop feeding cats in cattle barns are important. Reaching a consensus with stakeholders will require further studies of the ecological risks posed by free-ranging cats.

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.

An accessible scheme for monitoring free-roaming cat population trends

Free-roaming cats (FRCs) form nondomiciliary population groups that might lead to adverse environmental effects, as well as to welfare impairment of the cats themselves. Though criticized by ecologists, for the last two decades, the trap-neuter-return (TNR) programs were often employed aiming to manage these populations. At present, no accepted and accessible monitoring scheme exists to determine the effectiveness of those programs. In the current study, we present the reliability and validity of an applicable monitoring scheme, as an adjunct tool for a TNR program of FRC in an urban environment. The monitoring scheme is based on cat observation counts along randomly chosen transects. Fifty-four transects were repeatedly walked for three years, between 2012-2014, in 27 neighborhoods within an urban area of 19.3 Km2. Cat numbers counted in the 2014 observations were significantly higher than cat numbers found in the 2012 observations (prevalence ratio = 1.258, CI95%= 1.198-1.322, p < 0.001). The method revealed high reliability when different observers and different transects in the same neighborhood were compared (R 2 = 0.548 and R 2 = 0.391, respectively, for measuring cat counts per km, p < 0.001; and R 2 = 0.5 and R 2 = 0.74, respectively, for measuring neutering percentage, p < 0.001). This scheme was constructively validated by measurements of municipal data on the number of neutered cats and demonstrated high correlation (R 2 = 0.59, p < 0.001). Conducting cat observations using friendly calling and feeding resulted in an increased number of FRC observed per km walk (by 79% and 22%-30%, respectively). However, these manipulations did not alter the recorded percentage of neutered cats. The proposed scheme provides spatio-temporal data that can contribute to the management programs of such cat metapopulations in an urban environment.

Generalized spatial mark-resight models with incomplete identification: An application to red fox density estimates

The estimation of abundance of wildlife populations is an essential part of ecological research and monitoring. Spatially explicit capture-recapture (SCR) models are widely used for abundance and density estimation, frequently through individual identification of target species using camera-trap sampling.Generalized spatial mark-resight (Gen-SMR) is a recently developed SCR extension that allows for abundance estimation when only a subset of the population is recognizable by artificial or natural marks. However, in many cases, it is not possible to read the marks in camera-trap pictures, even though individuals can be recognized as marked. We present a new extension of Gen-SMR that allows for this type of incomplete identification.We used simulation to assess how the number of marked individuals and the individual identification rate influenced bias and precision. We demonstrate the model's performance in estimating red fox (Vulpes vulpes) density with two empirical datasets characterized by contrasting densities and rates of identification of marked individuals. According to the simulations, accuracy increases with the number of marked individuals (m), but is less sensitive to changes in individual identification rate (δ). In our case studies of red fox density estimation, we obtained a posterior mean of 1.60 (standard deviation SD: 0.32) and 0.28 (SD: 0.06) individuals/km2, in high and low density, with an identification rate of 0.21 and 0.91, respectively.This extension of Gen-SMR is broadly applicable as it addresses the common problem of incomplete identification of marked individuals during resighting surveys.

A Forensic Pathology Investigation of Dismembered Domestic Cats: Coyotes or Cults?

Dismembered cats ( Felis catus) have been found in North American schoolyards, parks, walkways, or lawns and sometimes result in local media attention. When a member of the public encounters these cats, they commonly report finding either the cranial or caudal half of a cat in a prominent location. Such findings cause public consternation and pose difficulties to investigators in identifying whether animal abuse has occurred and whether to concentrate resources on the investigation. This report describes necropsy results from 53 cats involved in such instances in the cities of Edmonton and St. Albert, Canada, from 2007 to 2016. We evaluated these results in relation to 2 hypotheses: that the dismembered cats were the result of human activity, or predation and scavenging by coyotes ( Canis latrans). The main postmortem features were canine tooth wounds in the neck accompanied by tearing of the subcutaneous structures, skin avulsion, broken claws, and removal of internal organs with the colon and intestine attached to and trailing from the carcass. Based on the nature of the lesions, along with other circumstances of the deaths of the cats in this study, we concluded that these dismembered cat remains resulted from coyote predation on living cats and scavenging of the bodies of cats that died of other causes. We offer additional information to assist veterinarians, veterinary pathologists, and civic officials in identifying the probable cause of death for cat carcasses provided by members of the public.

Defining the risk landscape in the context of pathogen pollution: Toxoplasma gondii in sea otters along the Pacific Rim

Pathogens entering the marine environment as pollutants exhibit a spatial signature driven by their transport mechanisms. The sea otter (Enhydra lutris), a marine animal which lives much of its life within sight of land, presents a unique opportunity to understand land-sea pathogen transmission. Using a dataset on Toxoplasma gondii prevalence across sea otter range from Alaska to California, we found that the dominant drivers of infection risk vary depending upon the spatial scale of analysis. At the population level, regions with high T. gondii prevalence had higher human population density and a greater proportion of human-dominated land uses, suggesting a strong role for population density of the felid definitive host of this parasite. This relationship persisted when a subset of data were analysed at the individual level: large-scale patterns in sea otter T. gondii infection prevalence were largely explained by individual exposure to areas of high human housing unit density, and other landscape features associated with anthropogenic land use, such as impervious surfaces and cropping land. These results contrast with the small-scale, within-region analysis, in which age, sex and prey choice accounted for most of the variation in infection risk, and terrestrial environmental features provided little variation to help in explaining observed patterns. These results underscore the importance of spatial scale in study design when quantifying both individual-level risk factors and landscape-scale variation in infection risk.

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.

Multistate matrix population model to assess the contributions and impacts on population abundance of domestic cats in urban areas including owned cats, unowned cats, and cats in shelters

Concerns over cat homelessness, over-taxed animal shelters, public health risks, and environmental impacts has raised attention on urban-cat populations. To truly understand cat population dynamics, the collective population of owned cats, unowned cats, and cats in the shelter system must be considered simultaneously because each subpopulation contributes differently to the overall population of cats in a community (e.g., differences in neuter rates, differences in impacts on wildlife) and cats move among categories through human interventions (e.g., adoption, abandonment). To assess this complex socio-ecological system, we developed a multistate matrix model of cats in urban areas that include owned cats, unowned cats (free-roaming and feral), and cats that move through the shelter system. Our model requires three inputs-location, number of human dwellings, and urban area-to provide testable predictions of cat abundance for any city in North America. Model-predicted population size of unowned cats in seven Canadian cities were not significantly different than published estimates (p = 0.23). Model-predicted proportions of sterile feral cats did not match observed sterile cat proportions for six USA cities (p = 0.001). Using a case study from Guelph, Ontario, Canada, we compared model-predicted to empirical estimates of cat abundance in each subpopulation and used perturbation analysis to calculate relative sensitivity of vital rates to cat abundance to demonstrate how management or mismanagement in one portion of the population could have repercussions across all portions of the network. Our study provides a general framework to consider cat population abundance in urban areas and, with refinement that includes city-specific parameter estimates and modeling, could provide a better understanding of population dynamics of cats in our communities.

Trap-Neuter-Return Activities in Urban Stray Cat Colonies in Australia

Simple Summary

Urban stray cats in Australia are poorly regarded because of wildlife predation and nuisance behaviors. However, current methods of population control via low level culling are ineffective. Effective control requires culling 30% to 50% of the population every six months, which is prohibitive for municipalities. Overseas, trap, neuter and return is frequently used to control urban cat numbers, and reduce nuisance behaviors, but is considered illegal in many Australian jurisdictions. An anonymous questionnaire was used to gather data on trap, neuter and return of urban stray cats in Australia. Respondents were mostly middle-aged women, and more participated as individuals than with organizations. Colony size decreased from a median of 11.5 cats to 6.5 cats over 2.2 years, through adoptions and desexing a median of 69% of the colony. Cats were fed once or twice daily, and provided with prophylactic health care. Programs were largely funded by private sources, with some funding by animal welfare organizations. We conclude that trap, neuter and return associated with high desexing rates in colonies, and adoption of kittens and friendly adults substantially reduces colony size, and improves the welfare of cats and kittens. This model is cost-effective for municipalities, and should be legalized in Australia.

Abstract

Trap, neuter and return (TNR) describes a non-lethal approach to the control of urban stray cat populations. Currently, in Australia, lethal control is common, with over 85% of cats entering some municipal pounds euthanized. No research has been published describing TNR activities in Australia. Adults involved with TNR in Australia were invited to participate. Data from 53 respondents were collected via an anonymous online questionnaire. Most respondents were females 36 to 65 years of age, and slightly more participated in TNR as individuals than as part of an organization. Respondents generally self-funded at least some of their TNR activities. The median number of colonies per respondent was 1.5 (range 1 to over 100). Median colony size declined from 11.5 to 6.5 cats under TNR over a median of 2.2 years, and the median percent reduction was 31%; this was achieved by rehoming cats and kittens and reducing reproduction. A median of 69% of cats in each colony were desexed at the time of reporting. Most respondents fed cats once or twice daily, and at least 28% of respondents microchipped cats. Prophylactic healthcare was provided to adult cats and kittens, commonly for intestinal parasites (at least 49%), and fleas (at least 46%); vaccinations were less common. Time-consuming activities for respondents were feeding (median 4 h/week) and locating resources (median 1.1 h/week). These findings indicate that TNR, when involving high desexing rates within colonies, adoption of kittens and friendly adults, and ongoing oversight by volunteer caretakers, can reduce cat numbers over time, improve health and welfare of cats and kittens, and is largely funded by private individuals and organizations.