Guidance for management of free-roaming community cats: a bioeconomic analysis

OBJECTIVES

This study used computer simulation modeling to estimate and compare costs of different free-roaming cat (FRC) management options (lethal and non-lethal removal, trap-neuter-return, combinations of these options and no action) and their ability to reduce FRC population abundance in open demographic settings. The findings provide a resource for selecting management approaches that are well matched for specific communities, goals and timelines, and they represent use of best available science to address FRC issues.

METHODS

Multiple FRC management approaches were simulated at varying intensities using a stochastic individual-based model in the software package Vortex. Itemized costs were obtained from published literature and expert feedback. Metrics generated to evaluate and compare management scenarios included final population size, total cost and a cost efficiency index, which was the ratio between total cost and population size reduction.

RESULTS

Simulations suggested that cost-effective reduction of FRC numbers required sufficient management intensity, regardless of management approach, and greatly improved when cat abandonment was minimized. Removal yielded the fastest initial reduction in cat abundance, but trap-neuter-return was a viable and potentially more cost-effective approach if performed at higher intensities over a sufficient duration. Of five management scenarios that reduced the final population size by approximately 45%, the three scenarios that relied exclusively on removal were considerably more expensive than the two scenarios that relied exclusively or primarily on sterilization.

CONCLUSIONS AND RELEVANCE

FRCs present a challenge in many municipalities, and stakeholders representing different perspectives may promote varying and sometimes incompatible population management policies and strategies. Although scientific research is often used to identify FRC impacts, its use to identify viable, cost-effective management solutions has been inadequate. The data provided by simulating different interventions, combined with community-specific goals, priorities and ethics, provide a framework for better-informed FRC policy and management outcomes.

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.

"State of the Mewnion": Practices of Feral Cat Care and Advocacy Organizations in the United States

Over the last several decades, feral cats have moved from the fringes to the mainstream in animal welfare and sheltering. Although many best practice guidelines have been published by national non-profits and veterinary bodies, little is known about how groups “in the trenches” actually operate. Our study sought to address that gap through an online survey of feral cat care and advocacy organizations based in the United States. Advertised as “The State of the Mewnion,” its topics included a range of issues spanning non-profit administration, public health, caretaking and trapping, adoptions of friendly kittens and cats, veterinary medical procedures and policies, data collection and program efficacy metrics, research engagement and interest, and relationships with wildlife advocates and animal control agencies. Respondents from 567 organizations participated, making this the largest and most comprehensive study on this topic to date. Respondents came primarily from grassroots organizations. A majority reported no paid employees (74.6%), served 499 or fewer feral cats per year (75.0%), engaged between 1 and 9 active volunteers (54.9%), and did not operate a brick and mortar facility (63.7%). Some of our findings demonstrate a shared community of practice, including the common use of a minimum weight of 2.0 pounds for spay/neuter eligibility, left side ear tip removals to indicate sterilization, recovery holding times after surgery commonly reported as 1 night for male cats and 1 or 2 nights for females, requiring or recommending to adopters of socialized kittens/cats that they be kept indoor-only, and less than a quarter still engaging in routine testing of cats for FIV and FeLV. Our survey also reveals areas for improvement, such as most organizations lacking a declared goal with a measurable value and a time frame, only sometimes scanning cats for microchips, and about a third not using a standardized injection site for vaccines. This study paints the clearest picture yet available of what constitutes the standard practices of organizations serving feral and community cats in the United States.

Two Methods of Monitoring Cats at a Landscape-Scale

Simple Summary

Feral cats are difficult to manage and harder to monitor. We report on the efficacy of Eradicat^® baiting and the cost and the efficacy of monitoring the activty of feral cats via camera-traps or track counts. Pre-baiting surveys for 2020 and 2021 suggested that the population of feral cats on Matuwa was very low, at 5.5 and 4.4 cats/100 km respectively, which is well below our target threshold of 10 cats/100 km. Post-baiting surveys then recorded 3.6 and 3.0 cats/100 km respectively, which still equates to a 35% and 32% reduction in cat activity despite initial low cat detection rate. Track counts recorded more feral cats than camera traps and were cheaper to implement.

Abstract

Feral cats are difficult to manage and harder to monitor. We analysed the cost and the efficacy of monitoring the pre- and post-bait abundance of feral cats via camera-traps or track counts using four years of data from the Matuwa Indigenous Protected Area. Additionally, we report on the recovery of the feral cat population and the efficacy of subsequent Eradicat^® aerial baiting programs following 12 months of intensive feral cat control in 2019. Significantly fewer cats were captured in 2020 (n = 8) compared to 2019 (n = 126). Pre-baiting surveys for 2020 and 2021 suggested that the population of feral cats on Matuwa was very low, at 5.5 and 4.4 cats/100 km, respectively, which is well below our target threshold of 10 cats/100 km. Post-baiting surveys then recorded 3.6 and 3.0 cats/100 km, respectively, which still equates to a 35% and 32% reduction in cat activity. Track counts recorded significantly more feral cats than camera traps and were cheaper to implement. We recommend that at least two methods of monitoring cats be implemented to prevent erroneous conclusions.

SARS-CoV-2 infection in domestic and feral cats: current evidence and implications

Current evidence indicates that cats play a limited role in COVID-19 epidemiology, and pets are probably dead-end hosts of SARS-CoV-2 and pose negligible risks of transmission to humans. Still, one health concept is to be adopted widely as a component of mitigation strategies to tackle the ongoing pandemic. Therefore, in terms of the magnitude of infection and potential to transmit SARS-CoV-2 to humans, our surveillance efforts should mainly focus on mustelids (especially minks, ferrets, and others) for early detection and control of infection. This will ensure that SARS-CoV-2 will not get established in the wild animal population of these susceptible species. We agree with Dr. Passarella Teixeira on the possibility of domestic and feral cats acting as an urban reservoir, subsequently transmitting the virus to human beings. However, it is less likely that such a phenomenon will be reported even if it has occurred due to the efficient and extensive human-to-human transmission of SARS-CoV-2.

Managing ecosystems in a sea of uncertainty: invasive species management and assisted colonizations

Managing ecosystems in the face of complex species interactions, and the associated uncertainty, presents a considerable ecological challenge. Altering those interactions via actions such as invasive species management or conservation translocations can result in unintended consequences, supporting the need to be able to make more informed decisions in the face of this uncertainty. We demonstrate the utility of ecosystem models to reduce uncertainty and inform future ecosystem management. We use Phillip Island, Australia, as a case study to investigate the impacts of two invasive species management options and consider whether a critically endangered mammal is likely to establish a population in the presence of invasive species. Qualitative models are used to determine the effects of apex predator removal (feral cats) and invasive prey removal (rabbits, rats, and mice). We extend this approach using Ensemble Ecosystem Models to consider how suppression, rather than eradication influences the species community; and consider whether an introduction of the critically endangered eastern barred bandicoot is likely to be successful in the presence of invasive species. Our analysis revealed the potential for unintended outcomes associated with feral cat control operations, with rats and rabbits expected to increase in abundance. A strategy based on managing prey species appeared to have the most ecosystem-wide benefits, with rodent control showing more favorable responses than a rabbit control strategy. Eastern barred bandicoots were predicted to persist under all feral cat control levels (including no control). Managing ecosystems is a complex and imprecise process. However, qualitative modeling and ensemble ecosystem modeling address uncertainty and are capable of improving and optimizing management practices. Our analysis shows that the best conservation outcomes may not always be associated with the top-down control of apex predators, and land managers should think more broadly in relation to managing bottom-up processes as well. Challenges faced in continuing to conserve biodiversity mean new, bolder, conservation actions are needed. We suggest that endangered species are capable of surviving in the presence of feral cats, potentially opening the door for more conservation translocations.

Kitts, West Indies

Toxoplasma gondii (T. gondii) is a cosmopolitan protozoan parasite that infects all warm-blooded species including humans. The definitive hosts of T. gondii are felid vertebrates including the domestic cat. Domestic cats shed oocysts for approximately two weeks in their feces after the primary infection. It has been shown that feline immunodeficiency virus (FIV) positive cats have a higher prevalence of and a higher titer of antibodies to T. gondii than those of FIV-negative cats. The main purposes of this study were to determine FIV prevalence and to investigate the oocysts shedding in FIV-positive and FIV-negative feral cats on St. Kitts. Fecal samples were collected from feral cats while their FIV statues were determined using a commercial SNAP kit. Total fecal DNA of each cat was tested for the presence of T. gondii DNA using a polymerase chain reaction (PCR) consistently detecting one genome equivalent. A FIV-positive status was detected in 18 of 105 (17.1%, 95% confidence interval (CI): 9.9%−24.3%) feral cats sampled. Furthermore, males were three times more likely to be FIV positive than females (p = 0.017) with an odds ratio of 3.93 (95% CI: 1.20–12.89). Adults were found to have at least twice the prevalence of FIV compared to cats younger than one year of age (p = 0.056) with an odds ratio of 3.07 (95% CI: 0.94–10.00). Toxoplasma gondii DNA was not detected in the feces of any of the 18 FIV-positive (95% CI: 0%−0.18%) and 87 FIV-negative cats (95% CI: 0%−0.04%). A follow-up study with a much bigger sample size is needed to prove or disprove the hypothesis that FIV-positive cats have a higher prevalence of shedding T. gondii oocysts than FIV-negative cats.

A triple threat: high population density, high foraging intensity and flexible habitat preferences explain high impact of feral cats on prey

Alien mammalian carnivores have contributed disproportionately to global loss of biodiversity. In Australia, predation by the feral cat and red fox is one of the most significant causes of the decline of native vertebrates. To discover why cats have greater impacts on prey than native predators, we compared the ecology of the feral cat to a marsupial counterpart, the spotted-tailed quoll. Individual prey are 20-200 times more likely to encounter feral cats, because of the combined effects of cats' higher population densities, greater intensity of home-range use and broader habitat preferences. These characteristics also mean that the costs to the prey of adopting anti-predator behaviours against feral cats are likely to be much higher than adopting such behaviours in response to spotted-tailed quolls, due to the reliability and ubiquity of feral cat cues. These results help explain the devastating impacts of cats on wildlife in Australia and other parts of the world.

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.

EVIDENCE OF LEPTOSPIRA SEROVARS IN WILDLIFE AND LEPTOSPIRAL DNA IN WATER SOURCES IN A NATURAL AREA IN EAST-CENTRAL ILLINOIS, USA

We identified seven Leptospira serovars in wildlife and the presence of leptospiral DNA in water sources at a natural area within a fragmented habitat in Illinois, US. These serovars have been implicated in domestic animal and human leptospirosis, a reemerging zoonotic disease, whose reservoirs include wildlife and domestic animals. We live trapped medium-sized mammals (n=351) near building (H-sites) or forest sites (F-sites). Using serology, we evaluated exposure to Leptospira (L. interrogans serovars Autumnalis, Bratislava, Canicola, Icterohaemorrhagiae, Pomona; L. kirschneri serovar Grippotyphosa; L. borgpetersenii serovar Hardjo). Using PCR, we tested for the presence of leptospires in eight water samples (ponds, creeks, and rainwater runoff) collected near trapping sites. We identified antibody titers in raccoons (Procyon lotor; 121/221) and Virginia opossums (Didelphis virginiana; 60/112), but not in feral cats (Felis catus; 0/18). We found significant differences in overall Leptospira seroprevalence between years (P=0.043) and animal's age in 2008 (P=0.005) and 2009 (P=0.003). Serovars Autumnalis, Bratislava, and Grippotyphosa showed significant differences among age groups with the highest seroprevalence in adults. Females had a higher seroprevalence for Icterohaemorragiae in 2008 (P=0.003) and Hardjo in 2009 (P=0.041). Risk of exposure to Leptospira was higher at F-sites compared to H-sites (odds ratio 2.3, 95% confidence interval 1.3-3.9, P=0.002). We captured more animals with titers >1:800 at H-sites, but there was no association between titer levels and capture site. Six of eight water sources were Leptospira-positive; however, there was no correlation between trapping locations of seropositive animals and positive water sources. Natural areas create opportunities for interspecies interactions, favoring leptospires transmission across species. Understanding that Leptospira serovars are present in natural areas is an integral part of the safe human and pet recreational use of these areas. Our study should raise awareness and build on public education designed to prevent disease transmission between species.

Spatial Analysis of a Cat-Borne Disease Reveals That Soil pH and Clay Content Are Risk Factors for Sarcocystosis in Sheep

Cat-borne parasites and their associated diseases have substantial impacts on human, livestock, and wildlife health worldwide. Despite this, large and detailed datasets that allow researchers to study broad-scale trends in the ecology of cat-borne diseases are either difficult to obtain or non-existent. One condition that is easily detected at slaughter is macroscopic sarcocystosis, a cat-borne parasitosis of sheep (Ovis aries). We conducted a cross-sectional study to describe the geographic distribution of sarcocystosis in sheep throughout South Australia and investigate ecosystem characteristics associated with the presence of disease. Data were obtained from two slaughterhouses which processed 3,865,608 sheep from 4,204 farms across 385,468 km² of South Australia's land mass for the period 2007-2017. A Poisson point process model was developed to quantify environmental characteristics associated with higher densities of sarcocystosis-positive farms. Sarcocystosis was highly clustered on a large island off of the Australian coast and the density of sarcocystosis-positive farms increased in areas of low soil pH (intensity ratio: 0.86, 95% CI: 0.78, 0.95) and high clay content. We hypothesize that region was confounded by, and predominately acted as a proxy for, cat density. Our results have broader implications regarding the health, welfare, economic, and conservation impacts of other cat-borne parasitosis, such as toxoplasmosis.

Native reptiles alter their foraging in the presence of the olfactory cues of invasive mammalian predators

Invasive mammalian predators are linked to terrestrial vertebrate extinctions worldwide. Prey naïveté may explain the large impact invasive predators have on native prey; prey may fail to detect and react appropriately to the cues of novel predators, which results in high levels of depredation. In Australia, the feral cat (Felis catus) and the red fox (Vulpes vulpes) are implicated in more than 30 animal extinctions and the naïveté of native prey is often used to explain this high extinction rate. Reptiles are one group of animals that are heavily preyed upon by F. catus and V. vulpes. However, very few studies have examined whether reptiles are naive to their cues. In this study, we examine the ability of two native reptile species (Morethia boulengeri and Christinus marmoratus) to detect and distinguish between the chemical cues of two invasive predators (V. vulpes and F. catus) and three native predators (spotted-tailed quoll, Dasyurus maculatus; dingo, Canis lupus dingo; eastern brown snake, Pseudonaja textilis), as well as two non-predator controls (eastern grey kangaroo, Macropus giganteus and water). We conducted experiments to quantify the effects of predator scents on lizard foraging (the amount of food eaten) during 1 h trials within Y-maze arenas. We found both study species reduced the amount they consumed when exposed to predator scents-both native and invasive-indicating that these species are not naive to invasive predators. An evolved generalized predator-recognition system, rapid evolution or learned behaviour could each explain the lack of naïveté in some native Australian reptiles towards invasive predators.

Australian native mammals recognize and respond to alien predators: a meta-analysis

Prey naiveté is a failure to recognize novel predators and thought to cause exaggerated impacts of alien predators on native wildlife. Yet there is equivocal evidence in the literature for native prey naiveté towards aliens. To address this, we conducted a meta-analysis of Australian mammal responses to native and alien predators. Australia has the world's worst record of extinction and declines of native mammals, largely owing to two alien predators introduced more than 150 years ago: the feral cat, Felis catus, and European red fox, Vulpes vulpes Analysis of 94 responses to predator cues shows that Australian mammals consistently recognize alien foxes as a predation threat, possibly because of thousands of years of experience with another canid predator, the dingo, Canis lupus dingo We also found recognition responses towards cats; however, in four of the seven studies available, these responses were of risk-taking behaviour rather than antipredator behaviour. Our results suggest that a simple failure to recognize alien predators is not behind the ongoing exaggerated impacts of alien predators in Australia. Instead, our results highlight an urgent need to better understand the appropriateness of antipredator responses in prey towards alien predators in order to understand native prey vulnerability.

Infections by pathogens with different transmission modes in feral cats from urban and rural areas of Korea

In this study, we examine prevalences of three infectious pathogens with different transmission modes (Bartonella henselae, hemoplasma, and Toxoplasma gondii) in feral cats from urban and rural habitats. Infection status of the three pathogens in blood samples (n = 117) was determined through molecular or serological diagnostic methods. Overall prevalence of hemoplasma, Toxoplasma gondii, and Bartonella henselae was 47.9%, 50%, and 35.7%, respectively. Comparing the two habitats, only seroprevalence of Bartonella henselae was significantly higher in urban cats. Based on the results, we discuss how pathogens with distinct transmission modes may show different prevalence between urban and rural habitat types.

Zoonotic disease transmission associated with feral cats in a metropolitan area: A geospatial analysis

Feral cats raise public health concerns due to their large population numbers and ability to harbour pathogens that cause disease in people, pets, and wildlife. Information regarding the potential for feral cats to intersect with areas frequented by humans is lacking. This study examined the potential for feral cats and human territories to overlap in the Richmond metropolitan area of Central Virginia. Feral cats (n = 275) were trapped for monthly trap-neuter-release (TNR) clinics from July to November 2016. A geographic information system (GIS) was used to map feral cat trapping locations, elementary and preschools, public parks, and community gardens, and to evaluate the potential for cat interaction with these areas, presuming a maximum habitat radius of 0.44 miles. We found that 8.0% of feral cats in the Richmond metropolitan area had potential to range onto public elementary or preschool property, and 81.5% of feral cats trapped in Richmond City had potential to roam into one or more places of interest, including elementary and preschool grounds, public parks, and community gardens. This provides public health, veterinary, and human health professionals with important information that can be used to focus resources in an effort to reduce zoonosis associated with feral cat populations.

Failure to detect Tritrichomonas foetus in a cross-sectional survey in the populations of feral cats and owned outpatient cats on St Kitts, West Indies

OBJECTIVES

For over two decades, feline trichomonosis caused by Tritrichomonas foetus has been recognized as a large-bowel protozoan disease of the domestic cat. It has a wide distribution, but no reports exist in the Caribbean. The objectives of this study were to detect the presence of T foetus and its prevalence in the domestic cat on St Kitts, West Indies.

METHODS

A cross-sectional study was performed between September 2014 and December 2015. This study recruited 115 feral cats from a trap-neuter-return program and 37 owned cats treated as outpatients at the university veterinary clinic. Fresh feces were inoculated in InPouch culture medium, as per the manufacturer's instructions. In addition, PCR was performed using primers for T foetus. DNA extraction with amplification using primers of a Feliscatus NADH dehydrogenase subunit 6 was used as a housekeeping gene for quality control.

RESULTS

Only two owned cats had reported diarrhea in the preceding 6 months. None of the 152 samples were positive on InPouch culture microscopic examination. Only 35/69 feral cat fecal DNA samples were positive for the housekeeping gene, of which none tested PCR positive for T foetus.

CONCLUSIONS AND RELEVANCE

T foetus was not detected by culture and PCR in feral cats and owned cats on St Kitts. A high proportion of PCR inhibitors in the DNA samples using a commercial fecal DNA kit can lead to underestimating the prevalence, which should be taken into consideration when a survey on gastrointestinal pathogens depends exclusively on molecular detection.

Habitat as a mediator of mesopredator-driven mammal extinction

A prevailing view in dryland systems is that mammals are constrained by the scarcity of fertile soils and primary productivity. An alternative view is that predation is a primary driver of mammal assemblages, especially in Australia, where 2 introduced mesopredators-feral cat (Felis catus) and red fox (Vulpes vulpes)-are responsible for severe declines of dryland mammals. We evaluated productivity and predation as drivers of native mammal assemblage structure in dryland Australia. We used new data from 90 sites to examine the divers of extant mammal species richness and reconstructed historic mammal assemblages to determine proportional loss of mammal species across broad habitat types (landform and vegetation communities). Predation was supported as a major driver of extant mammal richness, but its effect was strongly mediated by habitat. Areas that were rugged or had dense grass cover supported more mammal species than the more productive and topographically simple areas. Twelve species in the critical weight range (CWR) (35-5500 g) that is most vulnerable to mesopredator predation were extirpated from the continent's central region, and the severity of loss of species correlated negatively with ruggedness and positively with productivity. Based on previous studies, we expect that habitat mediates predation from red foxes and feral cats because it affects these species' densities and foraging efficiency. Large areas of rugged terrain provided vital refuge for Australian dryland mammals, and we predict such areas will support the persistence of CWR species in the face of ongoing mammal declines elsewhere in Australia.

Prey selection and dietary flexibility of three species of mammalian predator during an irruption of non-cyclic prey

Predators often display dietary shifts in response to fluctuating prey in cyclic systems, but little is known about predator diets in systems that experience non-cyclic prey irruptions. We tracked dietary shifts by feral cats (Felis catus), red foxes (Vulpes vulpes) and dingoes (Canis dingo) through a non-cyclic irruption of small mammalian prey in the Simpson Desert, central Australia. We predicted that all three predators would alter their diets to varying degrees as small mammals declined post irruption, and to test our predictions we live-trapped small mammals through the irruption event and collected scats to track predator diets. Red foxes and dingoes included a broader variety of prey in their diets as small mammals declined. Feral cats did not exhibit a similar dietary shift, but did show variable use and selectivity of small mammal species through the irruption cycle. Results were largely consistent with prior studies that highlighted the opportunistic feeding habits of the red fox and dingo. They also, however, showed that feral cats may exhibit less dietary flexibility in response to small mammal irruptions, emphasizing the importance of tracking predator diets before, during and after irruption events.

A Survey of Public Opinion on Cat (Felis catus) Predation and the Future Direction of Cat Management in New Zealand

Simple Summary

The need to balance the benefits of cat ownership with the prevention of wildlife predation in New Zealand evokes strong and opposing views. This paper evaluates public concern for wildlife predation by four categories of cats; owned cats, managed-stray cats, unmanaged-stray cats, and feral cats. In addition, public support for a National Cat Management Strategy and a range of management techniques are investigated. Although the participants expressed concern regarding wildlife predation by all four categories of cats, the highest levels of concern were predation by feral cats, followed by unmanaged stray cats, then managed stray cats, and finally owned cats. The large majority of participants were found to support the implementation of a National Cat Management Strategy. Management techniques for owned cats that obtained public support included; cat exclusion zones, limits on ownership numbers, microchipping, Council registration, and de-sexing. Trap-Neuter-Return (TNR) was the favoured management technique for managed stray cats, while TNR and lethal management techniques were equally favoured for unmanaged stray cats. Lethal control methods were favoured for feral cats. The findings presented in this paper will be useful to consider during the development of legislation relating to cat management and predation in New Zealand.

Abstract

Cat predation is a prominent issue in New Zealand that provokes strong and opposing views. We explored, via 1011 face-to-face questionnaires, public opinion on (a) support for a National Cat Management Strategy (78% support); (b) concern regarding predation of wildlife by owned and un-owned cats (managed stray, unmanaged stray, and feral cats); (c) the acceptability of management techniques for owned cats; and (d) the acceptability of population management techniques for un-owned cats. The highest concern was expressed regarding the predation of non-native and native wildlife by feral cats (60 and 86% repectively), followed by unmanaged stray cats (59 and 86% respectively), managed stray cats (54 and 82% respectively), and finally owned cats (38 and 69% repectively). Limits to the number of cats owned and cat restriction zones received high levels of support (>65%), and compulsory microchipping, Council registration, and de-sexing were supported by the majority (>58%). Public support of population control methods for unowned cats was explored, and the influence of participant demographic variables on responses is described. These findings provide insight into public opinion regarding the management of cats in New Zealand, which should be considered during the development of legislation in this area.

Invasive predators and global biodiversity loss

Invasive species threaten biodiversity globally, and invasive mammalian predators are particularly damaging, having contributed to considerable species decline and extinction. We provide a global metaanalysis of these impacts and reveal their full extent. Invasive predators are implicated in 87 bird, 45 mammal, and 10 reptile species extinctions-58% of these groups' contemporary extinctions worldwide. These figures are likely underestimated because 23 critically endangered species that we assessed are classed as "possibly extinct." Invasive mammalian predators endanger a further 596 species at risk of extinction, with cats, rodents, dogs, and pigs threatening the most species overall. Species most at risk from predators have high evolutionary distinctiveness and inhabit insular environments. Invasive mammalian predators are therefore important drivers of irreversible loss of phylogenetic diversity worldwide. That most impacted species are insular indicates that management of invasive predators on islands should be a global conservation priority. Understanding and mitigating the impact of invasive mammalian predators is essential for reducing the rate of global biodiversity loss.

Are we getting the full picture? Animal responses to camera traps and implications for predator studies

Camera trapping is widely used in ecological studies. It is often considered nonintrusive simply because animals are not captured or handled. However, the emission of light and sound from camera traps can be intrusive. We evaluated the daytime and nighttime behavioral responses of four mammalian predators to camera traps in road‐based, passive (no bait) surveys, in order to determine how this might affect ecological investigations. Wild dogs, European red foxes, feral cats, and spotted‐tailed quolls all exhibited behaviors indicating they noticed camera traps. Their recognition of camera traps was more likely when animals were approaching the device than if they were walking away from it. Some individuals of each species retreated from camera traps and some moved toward them, with negative behaviors slightly more common during the daytime. There was no consistent response to camera traps within species; both attraction and repulsion were observed. Camera trapping is clearly an intrusive sampling method for some individuals of some species. This may limit the utility of conclusions about animal behavior obtained from camera trapping. Similarly, it is possible that behavioral responses to camera traps could affect detection probabilities, introducing as yet unmeasured biases into camera trapping abundance surveys. These effects demand consideration when utilizing camera traps in ecological research and will ideally prompt further work to quantify associated biases in detection probabilities.

Effects of feral cats on the evolution of anti-predator behaviours in island reptiles: insights from an ancient introduction

Exotic predators have driven the extinction of many island species. We examined impacts of feral cats on the abundance and anti-predator behaviours of Aegean wall lizards in the Cyclades (Greece), where cats were introduced thousands of years ago. We compared populations with high and low cat density on Naxos Island and populations on surrounding islets with no cats. Cats reduced wall lizard populations by half. Lizards facing greater risk from cats stayed closer to refuges, were more likely to shed their tails in a standardized assay, and fled at greater distances when approached by either a person in the field or a mounted cat decoy in the laboratory. All populations showed phenotypic plasticity in flight initiation distance, suggesting that this feature is ancient and could have helped wall lizards survive the initial introduction of cats to the region. Lizards from islets sought shelter less frequently and often initially approached the cat decoy. These differences reflect changes since islet isolation and could render islet lizards strongly susceptible to cat predation.

Top-predator control-induced trophic cascades: an alternative hypothesis to the conclusion of Colman et al

Colman et al. (2014 Proc. R. Soc. B 281, 20133094. (doi:10.1098/rspb.2013.3094)) recently argued that observed positive relationships between dingoes and small mammals were a result of top-down processes whereby lethal dingo control reduced dingoes and increased mesopredators and herbivores, which then suppressed small mammals. Here, I show that the prerequisite negative effects of dingo control on dingoes were not shown, and that the same positive relationships observed may simply represent well-known bottom-up processes whereby more generalist predators are found in places with more of their preferred prey. Identification of top-predator control-induced trophic cascades first requires demonstration of some actual effect of control on predators, typically possible only through manipulative experiments with the ability to identify cause and effect.

Reliability and Validity of a Survey of Cat Caregivers on Their Cats' Socialization Level in the Cat's Normal Environment

Simple Summary

Many animal welfare organizations accept cats with no known behavioral history. It can be difficult to differentiate between a frightened but well-socialized cat and an unsocialized cat in an animal shelter environment. Making this distinction can save lives, yet currently there is no valid tool. Here we measured the quality of a survey designed to determine socialization level using information from the cat’s caregiver about a cat’s usual behavior around people in the cat’s normal environment. This survey will be used to help develop an effective process that accurately differentiates cats by their socialization levels in animal shelters.

Abstract

Stray cats routinely enter animal welfare organizations each year and shelters are challenged with determining the level of human socialization these cats may possess as quickly as possible. However, there is currently no standard process to guide this determination. This study describes the development and validation of a caregiver survey designed to be filled out by a cat’s caregiver so it accurately describes a cat’s personality, background, and full range of behavior with people when in its normal environment. The results from this survey provided the basis for a socialization score that ranged from unsocialized to well socialized with people. The quality of the survey was evaluated based on inter-rater and test-retest reliability and internal consistency and estimates of construct and criterion validity. In general, our results showed moderate to high levels of inter-rater (median of 0.803, range 0.211–0.957) and test-retest agreement (median 0.92, range 0.211–0.999). Cronbach’s alpha showed high internal consistency (0.962). Estimates of validity did not highlight any major shortcomings. This survey will be used to develop and validate an effective assessment process that accurately differentiates cats by their socialization levels towards humans based on direct observation of cats’ behavior in an animal shelter.

Practical Physical and Behavioral Measures to Assess the Socialization Spectrum of Cats in a Shelter-Like Setting during a Three Day Period

Simple Summary

Animal welfare organizations accept large numbers of cats with no known history. Because shelters are often highly stressful environments for cats, it is likely to be difficult to differentiate a frightened cat that is socialized to humans from a feral cat that is not. However, this distinction can help channel cats into appropriate dispositions. We conducted structured assessments to measure various behaviors and their potential to distinguish socialization levels. Our results show that a specific set of behaviors are only exhibited by more socialized cats. Many cats needed time to adjust to the shelter-type setting to show these socialized behaviors.

Abstract

Animal welfare organizations routinely accept large numbers of cats with unknown histories, and whose backgrounds vary from well-socialized pets to cats that have had little or no contact with humans. Agencies are challenged with making the determination of socialization level in a highly stressful environment where cats are often too frightened to show typical behaviors. A variety of structured behavioral assessments were conducted in a shelter-like environment, from intake through a three day holding period, on cats from the full range of socialization as reported by their caregivers. Our results show that certain behaviors such as rubbing, playing, chirping, having the tail up or being at the front of the cage were found to be unique to More Socialized cats. While not all more socialized cats showed these behaviors, cats that did were socialized. Assessing the cats throughout the three day period was beneficial in eliciting key behaviors from shyer and more frightened cats. These results will be used in future work to develop an assessment tool to identify the socialization status of cats as a standardized guide for transparent and reliable disposition decisions and higher live release rates for cats in animal shelters.

Physical and Behavioral Measures that Predict Cats' Socialization in an Animal Shelter Environment during a Three Day Period

Simple Summary

Information from surveys completed by the cats’ caregivers provided a score for the level of socialization of cats. We examined the effectiveness of structured assessments and measures in their ability to distinguish More and Less Socialized cats in a shelter-like setting over a three day period. Statistical models were developed that best predicted More and Less Socialized cats. Measures from these models were used to calculate a point system where more points indicated more socialization. In combination with key socialized behaviors, these points were able to fairly accurately distinguish More Socialized from Less Socialized cats.

Abstract

Animal welfare organizations typically take in cats with unknown levels of socialization towards humans, ranging from unsocialized cats well-socialized but lost pets. Agencies typically determine the socialization status and disposition options of cats within three days, when even a well-socialized pet may be too frightened of the unfamiliar surroundings to display its typical behavior. This is the third part of a three-phase project to develop and evaluate a reliable and valid tool to predict cats’ socialization levels. We recruited cats from the full spectrum of socialization and, using information from the cats’ caregivers regarding typical behavior toward familiar and unfamiliar people, assigned each cat to a Socialization Category. This information was compared to the cats’ behavior during three days of structured assessments conducted in a shelter-like setting. The results of logistic regression modeling generated two models using assessments from the mornings of the second and third day, focusing on predicting shyer or more aloof but socialized cats. Using the coefficients from each of these models, two sets of points were calculated which were useful in differentiating More and Less Socialized cats. In combination with key socialized behaviors, these points were able to fairly accurately identify More and Less Socialized cats.