‘Science denialism’ is also about outdoor cats

Loss, S. R., Will, T., Longcore, T., & Marra, P. P. (2018). Responding to misinformation and criticisms regarding United States cat predation estimates. Biological Invasions, 20(12), 3385-3396.
Misinformation (or denialism), the disingenuous assertion of information contradicting overwhelming scientific consensus, increasingly poses a challenge for invasion biology. The issue of free-ranging domestic cats (Felis catus) provides an example of this misinformation: overwhelming consensus shows that cats are invasive species that impact wildlife and human health yet free-ranging cat advocates propagate misinformation about such impacts to support policies keeping cats on the landscape. These advocates also attempt to discredit peer-reviewed scientific research on cat impacts, as exemplified by the response to a high-profile paper estimating cats annually kill billions of U.S. birds and mammals (Loss et al. in Nat Commun 4:1396, 2013). Although favorably received by scientific and invasive species management communities, an effort was launched to discredit this paper by criticizing its methods, including a report commissioned by a feral cat advocacy group and a post by a feral cat blogger. These same organizations and individuals have made similar criticisms at scientific conferences and policy roundtables. Given the realized effects of this campaign in influencing invasive species policy, we here respond to these criticisms and show they are characterized by numerous errors and misrepresentations. We conclude that the criticisms are part of the broader campaign to fabricate doubt about outdoor cat impacts and stymie policies favoring removal of cats from the landscape. Because misinformation surrounding cats is emblematic of the broader issue of misinformation and denialism, this response will not only facilitate evidence-based policy for managing cats but also stimulate research and discussion into causes and impacts of misinformation in invasion biology.

Involvement in a Northern California community on the feral cat problem

Lando, C. A. (2016). Building involvement in a Northern California community on a targeted public health issue: a service announcement on the feral cat problem in Chico.  Faculty of California State University, Chico

The primary purpose of this study is to examine the health and environmental issues caused by feral cats and to offer solutions to control the growth of feral cat colonies in a Northern California community. Research supports the claim that feral cats, or community cats are a community problem and a community’s responsibility. Therefore, the local government, local animal welfare groups, and concerned citizens need to work together to find viable solutions.
Furthermore, the City of Chico’s Animal Control Officer estimates there are approximately 14,000 feral cats living on the streets and in the parks of the city of Chico. Several animal welfare organizations have worked to reduce this number through adoption, offering permanent housing, or trapping, vaccinating, neutering and returning cats to their colonies. The city’s euthanasia policy is only in effect for sick animals brought into the shelter by citizens. Due to budget cuts and lack of space, the city cannot house abandoned or surrendered animals. Therefore, the city refers calls about feral cats to one of the other animal welfare agencies.
The results of this project have shown that a collaborative organization consisting of members of concerned citizens and animal welfare groups can offer the best solutions to the feral cat dilemma. Accessing information about the ways other communities have addressed the feral cat problem is helpful. Working together individual organizations can share strategies for implementing fundraising activities, publicity, grant writing, and other issues such as purchasing pet supplies and food.
In addition, California State University, Chico, needs to take a more active role in disseminating information to its students about not releasing cats at the end of the school year. This information should be provided during orientation and through the university’s newspaper. Research has shown that an ongoing public service announcement through television and radio is one of the best ways to reach the most people. Public service announcements offer information and resources available to
citizens for assistance with a feral cat problem. 

Semi-Stray Dogs and Graduated Humanness

Sandoval-Cervantes, I. (2016). Semi-Stray Dogs and Graduated Humanness: The Political Encounters of Dogs and Humans in Mexico. In Companion Animals in Everyday Life (pp. 169-181). Palgrave Macmillan US.

In January 2013, a pack of stray dogs was accused with murder in one of Mexico City’s poorest and most populated boroughs. Images of the dogs, expert testimonies, and protests saturated the media. Eventually, the dogs were ambiguously exonerated. This event raises important questions that show the intricate ways in which human–dog relationships in Mexico have been historically constructed around notions of humanness, and informed by notions of class, race, and citizenship. I rely on the concept of “graduated humanness” to analyze the case of the “doglinquents” of Mexico City. I conclude that the concept of “graduated humanness” can illuminate how humans and animal rights are used contextually to “save” specific nonhuman beings while not addressing the larger structural conditions that frame the lives of humans and nonhumans.

Polarized opinions approach on Feral Cat Management

Lorden, R. (2016). Polarized Opinions and Shared Goals: Feral Cat Management in an Academic Community in Kentucky. In Companion Animals in Everyday Life (pp. 183-200). Palgrave Macmillan US.

Although there is general agreement among government agencies, conservation groups and animal welfare organizations that cat populations need to be managed, the management of cats is frequently a topic of debate between biologists/environmental groups and animal welfare/animal rights advocacy groups. The two groups’ beliefs are polarized in regard to impacts on wildlife, management strategies and efficacy of trap-and-neuter (TNR) programs. Concerns of conservation biologists relate to cats as predators, but welfare proponents feel that humans must take responsibility for free-ranging house pets and their feral offspring. It is not surprising that discussions of feral cat management become volatile. Much of the debate hinges upon whether management solutions should use lethal or non-lethal control strategies. Conservation biologists largely support cat euthanasia, while animal welfare activists support non-lethal treatments such as TNR for free-ranging cats. The issues of this larger conservancy/welfare debate framed the discourse of the cat problem and guided solution strategies at Eastern Kentucky University, where a population of cats has existed on the campus for many years. A tentative agreement has been forged between an administration that subscribed to a trap and remove policy, and a network of TNR volunteers. Both sides have focused on the common goal of a reduction in the number of campus cats. In addition, both sides have realized that each setting has its own particular constraints and that solutions must be tailored to those situations. Instead of resorting to invective, data are being collected. When well-meaning people meet and focus on solutions to a shared goal, positive outcomes become possible.

Camera trapping to estimate free-ranging cats in towns

Elizondo, E. C., & Loss, S. R. (2016). Using trail cameras to estimate free-ranging domestic cat abundance in urban areas. Wildlife Biology, 22(5), 246-252.

The domestic cat Felis catus is one of the most ecologically harmful invasive species on earth. Predation by free-ranging cats poses a serious global threat to small vertebrates and is a leading source of anthropogenic mortality for birds and small mammals in North America. However, little is known about the size of cat populations, especially in urban areas where both cats and wildlife are abundant. Methods to quantify free-ranging cat populations are needed to understand the magnitude of threats facing wildlife populations and to inform decisions about prioritizing conservation and cat population management. We assessed the utility of trail cameras and sight—resight analysis for estimating free-ranging cat abundance in a small urban area (Stillwater, OK, USA). We also evaluated whether relationships exist between cat abundance and both urban development intensity and human population density. Even with relatively large cat populations, we identified the vast majority (∼96.5%) of individual cats in both day-time and night-time photos. We found no relationship between cat abundance and either urban development intensity or human population density. This finding combined with the large numbers of cats observed suggests that cats may be abundant in our study area regardless of urban context. Sampling freeranging cat populations across a broad range of urbanization intensities that capture a variety of human behaviors and/or cat management policies is needed to shed light on the drivers of cat population abundance. Trail cameras show promise as a highly useful tool for achieving this objective in the context of wildlife conservation management.

High-impact conservation: invasive mammal eradications from the islands of western Mexico

Aguirre-Muñoz, A., Croll, D. A., Donlan, C. J., Henry III, R. W., Hermosillo, M. A., Howald, G. R., ... & Samaniego-Herrera, A. (2008). High-impact conservation: invasive mammal eradications from the islands of western Mexico. AMBIO: A Journal of the Human Environment, 37(2), 101-107.

Islands harbor a disproportionate amount of the earth's biodiversity, but a significant portion has been lost due in large part to the impacts of invasive mammals. Fortunately, invasive mammals can be routinely removed from islands, providing a powerful tool to prevent extinctions and restore ecosystems. Given that invasive mammals are still present on more than 80% of the world's major islands groups and remain a premier threat to the earth's biodiversity, it is important to disseminate replicable, scaleable models to eradicate invasive mammals from islands. We report on a successful model from western México during the past decade. A collaborative effort between nongovernmental organizations, academic biologists, Mexican government agencies, and local individuals has resulted in major restoration efforts in three island archipelagos. Forty-two populations of invasive mammals have been eradicated from 26 islands. For a cost of USD 21 615 per colony and USD 49 370 per taxon, 201 seabird colonies and 88 endemic terrestrial taxa have been protected, respectively. These conservation successes are a result of an operational model with three main components: i) a tri-national collaboration that integrates research, prioritization, financing, public education, policy work, capacity building, conservation action, monitoring, and evaluation; ii) proactive and dedicated natural resource management agencies; and iii) effective partnerships with academic researchers in México and the United States. What is now needed is a detailed plan to eradicate invasive mammals from the remaining islands in the region that integrates the needed additional financing, capacity, technical advances, and policy issues. Island conservation in western México provides an effective approach that can be readily applied to other archipelagos where conservation efforts have been limited.

Inefficient TNR

Kilgour, R. J., Magle, S. B., Slater, M., Christian, A., Weiss, E., & DiTullio, M. (2016). Estimating free-roaming cat populations and the effects of one year Trap-Neuter-Return management effort in a highly urban area. Urban Ecosystems, 1-10.

Free-roaming cat populations are increasing in urban areas around the world. Management strategies remain controversial, as attempts to rapidly minimize the impact of cats may conflict with finding an ethical means of population reduction in this domesticated species. Trap-Neuter-Return (TNR) is a non-lethal strategy which can theoretically lead to population decline with an ethical approach. The present study aimed to estimate free-roaming cat populations and also to measure the efficacy of a one-year TNR campaign in a highly urban area. Using a sight/resight methodology, we examined free-roaming cat populations in four sites across two neighbourhoods (Harlem and Bedford-Stuyvesant) in New York City. Sampling was repeated after 1 year, during which an intensive TNR effort occurred in each of those areas. Results from this study found population estimates range from 2.6-4.1 cats/km. Additionally, we found between 78-98% turnover in each study area. After one year of TNR, the proportion of sterilised individuals in our treatment sites increased to 50%. Model results suggest there is no evidence that sterilised individuals are more likely to be encountered, indicating that sterilisation may not affect movement patterns of cats. Free-roaming cats occur at high densities at all study sites, though populations varied, even within the same neighbourhood. We found evidence of considerable migration within study sites, which further complicates the application of a sterilisation management strategy. Management strategies directed toward free-roaming cats, such as TNR, may require a broad-scale approach, involving different facets of the community and should occur over multiple years.

Canine pathogens among wolves from the Alaska peninsula

Watts, D. E., & Benson, A. M. (2016). Prevalence of antibodies for selected canine pathogens among wolves from the Alaska peninsula, USA. Journal of Wildlife Diseases.

We collected blood samples from wolves (Canis lupus) on the Alaska Peninsula, southwest Alaska, USA, 2006–2011 and tested sera for antibodies to canine adenovirus (CAV), canine coronavirus (CCV), canine distemper virus (CDV), canine herpesvirus (CHV), canine parainfluenza (CPI), canine parvovirus (CPV), Neospora caninum, and Toxoplasma gondii. Detected antibody prevalence was 90% for CAV, 28% for CCV, 12% for CDV, 93% for CHV, 0% for CPI, 20% for CPV, and 86% for T. gondii. Prevalence of CCV antibodies suggested a seasonal pattern with higher prevalence during spring (43%) than in fall (11%). Prevalence of CCV antibodies also declined during the 6-yr study with high prevalence during Spring 2006–2008 (80%, n=24) and low prevalence during Spring 2009–2011 (4%, n=24). Prevalence of N. caninum and T. gondii antibodies were highly variable in the study area during 2006–2011. Results suggested that some pathogens might be enzootic on the Alaska Peninsula (e.g., CAV and CHV) while others may be epizootic (e.g., CCV, N. caninum, T. gondii).

US public opinion on humane treatment of stray cats

Chu, K., & Anderseon, W. M. US Public Opinion on Humane Treatment of Stray Cats. 2007. Alley Cat Allies: Bethesda, MD, 6.

An overwhelming majority of Americans believe that leaving a stray cat outside to live out his life is more humane than having him caught and put down, according to a nationally representative survey conducted for Alley Cat Allies by Harris Interactive in April and May 2007. These results reveal a significant disparity between the public’s humane ethic and the operating policy of most U.S. animal pounds and shelters.
 The current animal control policy is that it is more humane to kill a stray cat now than let him live out his life outdoors; however, this policy rests on untenable bases. While those bases will be discussed in detail below, what is most salient to note is that the socalled humane ethic of the animal control and sheltering system ends more cats’ lives than does any other documented cause of death.

An international comparison of the attitudes of urban people regarding predation by pet cats

Hall, C. M., Adams, N. A., Bradley, J. S., Bryant, K. A., Davis, A. A., Dickman, C. R., ... & Pollock, K. H. (2016). Community Attitudes and Practices of Urban Residents Regarding Predation by Pet Cats on Wildlife: An International Comparison. PLoS One, 11(4), e0151962.

International differences in practices and attitudes regarding pet cats' interactions with wildlife were assessed by surveying citizens from at least two cities in Australia, New Zealand, the UK, the USA, China and Japan. Predictions tested were: (i) cat owners would agree less than non-cat owners that cats might threaten wildlife, (ii) cat owners value wildlife less than non-cat owners, (iii) cat owners are less accepting of cat legislation/restrictions than non-owners, and (iv) respondents from regions with high endemic biodiversity (Australia, New Zealand, China and the USA state of Hawaii) would be most concerned about pet cats threatening wildlife. Everywhere non-owners were more likely than owners to agree that pet cats killing wildlife were a problem in cities, towns and rural areas.

Cat husbandry practices in different countries. (a) Percentage of households that own one, two or more than two cats (b) Percentage of cats kept in different conditions of confinement (c) Percentage of desexed cats. (d) Percentage of cats that have ever caught vertebrate prey.

Agreement amongst non-owners was highest in Australia (95%) and New Zealand (78%) and lowest in the UK (38%). Irrespective of ownership, over 85% of respondents from all countries except China (65%) valued wildlife in cities, towns and rural areas. Non-owners advocated cat legislation more strongly than owners except in Japan. Australian non-owners were the most supportive (88%), followed by Chinese non-owners (80%) and Japanese owners (79.5%). The UK was least supportive (non-owners 43%, owners 25%). Many Australian (62%), New Zealand (51%) and Chinese owners (42%) agreed that pet cats killing wildlife in cities, towns and rural areas was a problem, while Hawaiian owners were similar to the mainland USA (20%).

Percentage agreement of cat owners (dark blue) and non-owners (light blue) in each country to eight survey items: (a) There is a need for cat legislation (b) All cats should be kept in at night time (c) Cats should be kept on their owner's property at all times (d) It is important to have wildlife in cities, towns and rural areas (e) Pet cats killing wildlife in cities, towns and rural areas is a serious problem (f) Pet cats on farms are harmful to wildlife (g) Pet cats in nature reserves are harmful to wildlife (h) Except for a cat owned by a breeder, all cats should be desexed.

Thus high endemic biodiversity might contribute to attitudes in some, but not all, countries. Husbandry practices varied internationally, with predation highest where fewer cats were confined. Although the risk of wildlife population declines caused by pet cats justifies precautionary action, campaigns based on wildlife protection are unlikely to succeed outside Australia or New Zealand. Restrictions on roaming protect wildlife and benefit cat welfare, so welfare is a better rationale.

Leptospira in free-living sea lions in California and Baja California

Rosalía Avalos-Téllez, Erika M. Carrillo-Casas, Daniel Atilano-López, Carlos R. Godínez-Reyes, Efrén Díaz-Aparicio, David Ramírez-Delgado, María F. Ramírez-Echenique, Margarita Leyva-Leyva, Gerardo Suzán, and Francisco Suárez-Güemes (2016) Pathogenic Leptospira serovars in free-living sea lions in the gulf of California and along the Baja California coast of Mexico. Journal of Wildlife Diseases In-Press.


The California sea lion (Zalophus californianus), a permanent inhabitant of the Gulf of California in Mexico, is susceptible to pathogenic Leptospira spp. infection, which can result in hepatic and renal damage and may lead to renal failure and death. During summer 2013, we used the microscopic agglutination test (MAT) to investigate the prevalence of anti-Leptospira antibodies in blood of clinically healthy sea lion pups from seven rookery islands on the Pacific Coast of Baja California (Pacific Ocean) and in the Gulf of California. We also used PCR to examine blood for Leptospira DNA. Isolation of Leptospira in liquid media was unsuccessful. We found higher antibody prevalence in sea lions from the rookery islands in the gulf than in those from the Pacific Coast. Antibodies against 11 serovars were identified in the Gulf of California population; the most frequent reactions were against serovars Bataviae (90%), Pyrogenes (86%), Wolffi (86%), Celledoni (71%), and Pomona (65%). In the Pacific Ocean population, MAT was positive against eight serovars, where Wolffi (88%), Pomona (75%), and Bataviae (70%) were the most frequent. Serum samples agglutinated with more than one Leptospira serovar. The maximum titer was 3,200. Each island had a different serology profile, and islands combined showed a distinct profile for each region. We detected pathogenic Leptospira DNA in 63% of blood samples, but we found no saprophytic Leptospira. Positive PCR results were obtained in blood samples with high and low MAT titers. Together, these two methods enhance the diagnosis and interpretation of sea lion leptospirosis. Our results may be related to human activities or the presence of other reservoirs with which sea lions interact, and they may also be related to sea lion stranding.

Use of camera traps to examine the mesopredator release hypothesis in a fragmented landscape

Cove, M. V., Jones, B. M., Bossert, A. J., Clever Jr, D. R., Dunwoody, R. K., White, B. C., & Jackson, V. L. (2012). Use of camera traps to examine the mesopredator release hypothesis in a fragmented Midwestern landscape. The American Midland Naturalist, 168(2), 456-465.

The mesopredator release hypothesis (MRH) has been suggested as a reason why many mammalian generalist mesopredators flourish and become abundant. However, the MRH has only been examined in a limited number of field studies. Some studies have argued that coyotes (Canis latrans) act as top predators in fragmented forest systems and coyote presence has a positive effect on song bird diversity and abundance by controlling mesopredator abundance. We integrated camera trap data and occupancy modeling to determine the factors that affect coyote detection probability and habitat use in a fragmented suburban landscape in central Missouri. We then examined the influence of coyote presence and other habitat variables on mesopredator detection probability and habitat use in the same system. Coyote detection was negatively related to increasing forest cover, whereas red fox (Vulpes vulpes) detection was positively related to increasing urbanization. Coyote occurrence models suggested little habitat selection, while the mesopredator occurrence models suggested an affinity for urbanization. Although there was a slight negative effect of coyote presence on site use by other mesopredators, we suggest that the smaller species are better adapted to coexisting with humans and thus have increased in abundance.

Proposal on solutions to stray dog problem in American cities

Lyu, P. (2015). Proposal on Solutions to Stray Dog Problem in American Cities. Journal of Political Sciences & Public Affairs, 2015.

With the development of cities, stray dogs have become one of the most serious public management problems in American cities, and a widespread concern by the public. Stray dogs have many negative impacts on city environment and human health. There are many causes for the stray dog problem. Strengths and weakness of each solution was analyzed. A Five Year Plan to better solve the stray dog problem was proposed by this proposal.

Distribution and correlates of feral cat trapping permits in Los Angeles

Kingsley, G. (2015). Distribution and correlates of feral cat trapping permits in Los Angeles, California (doctoral dissertation, University of Southern California)

Uncontrolled populations of feral cats in urban settings have become of concern to public officials, wildlife scientists, animal rights advocates and the public in general due to the risks they pose to public health, urban wildlife, and esthetics. Solutions to the problem of unmanaged cat populations in cities have been limited in scope by the lack of actual data on feral cats and the urban geographic ranges they occupy. Full extent censuses and environmental analyses have not been collected or performed due to the resources allocations and costs involved. A method for collecting this data without the use of field crews and research summaries exists in the form of unused paper records. Past studies on the problem have used data mining of available records to model cat territories and densities (Aguilar and Farnworth 2012). This approach mitigates the cost while providing information regarding the distributions of these animals. This thesis investigates the spatial properties of feral cat populations in a large metropolitan area (Los Angeles, California) using a previously non-spatialized dataset as a proxy for concentrations of feral cats. The following case study explores two matters: 1) development of a workflow to create a spatial model of feral cat extents from geographic data brought into an analyzable format and 2) analysis of the model data to determine what, if any, variables are correlated with these distributions. The data used for the model were obtained from the City in the form of paper records and successfully imported into a Geographic Information System. Densities of applications were determined from the cleaned and geocoded records and concentrations of both raw density and patterns of clustering were mapped. Modeling of correlations found positive associations with population density and a weak negative correlation with median income. The analysis was assessed and future work on this type of data was considered.

Understanding public perceptions of risk regarding outdoor pet cats to inform conservation action

Gramza, A., Teel, T., VandeWoude, S., & Crooks, K. (2016). Understanding public perceptions of risk regarding outdoor pet cats to inform conservation action. Conservation Biology, 30 (2): 276–286

Free-ranging domestic cats (Felis catus) incur and impose risks on ecosystems and represent a complex issue of critical importance to biodiversity conservation and cat and human health globally. Prior social science research on this topic is limited and has emphasized feral cats even though owned cats often comprise a large proportion of the outdoor cat population, particularly in urban areas. To address this gap, we examined public risk perceptions and attitudes toward outdoor pet cats across varying levels of urbanization, including along the wildland-urban interface, in Colorado, USA. An analysis of 1397 completed surveys showed that residents did not view all types of risks uniformly; they viewed risks of cat predation on wildlife and carnivore predation on cats as more likely than risks of disease transmission to and from wildlife. Additionally, risk perceptions were related to attitudes, prior experiences with cats and cat-wildlife interactions, and cat owner behavior. Findings suggest that changes in risk perceptions may result in behavior change, and they offer insight for communication aimed at promoting risk aversive behaviors and cat management strategies that are acceptable to the public and that directly advance the conservation of native species.

Pathogen exposure varies widely among sympatric populations of wild and domestic felids

Carver, S., Bevins, S. N., Lappin, M. R., Boydston, E. E., Lyren, L. M., Alldredge, M. W., Logan K.A., Sweanor, L.L., Riley, S.P.D., Klein Serieys, L.E., Fisher, R.N., Vickers,T.W., Boyce, W.M., McBride, R., Cunningham, M.C., Jennings, M., Lewis, J.S., Lunn, T. Crooks, K.R. & VandeWoude, S. (2015). Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States. Ecological Applications.
Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened >1,000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus) and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure-providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban landuse predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest inter-specific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey. Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intra-specific interactions through pile-up of home ranges. Beyond these regional and pathogen specific relationships, proximity to the wildland urban interface did not generally increase the probability of disease exposure in wild or domestic felids, emphasizing the importance of local ecological determinants. Indeed, pathogen exposure was often negatively associated with the wildland urban interface for all felids. Our analyses suggest cross-species pathogen transmission events around this interface may be infrequent, but followed by self-sustaining propagation within the new host species.

Epidemiology of FeLV and FIV in USA and Canada

Chhetri, B. (2015). Spatial and temporal epidemiology of feline immunodeficiency virus and feline leukemia virus infections in the United States and Canada (Doctoral dissertation, The University of Guelph).

This thesis investigates the geographical and temporal variations in feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infections, and the importance of known risk factors for these infections relative to each other in the United States and Canada. In addition, the effect of the modifiable areal unit problem (MAUP) on commonly used spatial analysis methods was assessed.
Choropleth mapping and spatial scan testing revealed that compared to FIV, FeLV infection was predominant in western regions, and FIV infection was predominant in eastern regions of the US. A multilevel case-case study design for comparison of FIV and FeLV infections indicated that cats that were adult, male, healthy, or outdoor cats were more likely to be seropositive for FIV compared to FeLV when compared to juvenile, female, sick or cats kept exclusively indoors. Neuter status and testing at clinic or shelter did not differ significantly between the two infections. Time series analysis did not reveal an increasing or decreasing trend in FIV or FeLV seropositivity among cats tested at the Animal Health Laboratory (AHL) from 1999-2012. Further, the FIV vaccine introduction did not have a significant effect on changing seroprevalence for FIV. It was evident from this study that commonly used spatial epidemiological methods (Moran's I, the spatial scan test and spatial Poisson regression modeling) are sensitive to the choice of the spatial aggregation scale (state, county, postal code levels) for analysis, (i.e., are affected by the MAUP). The MAUP effect was expressed as differences in strength and significance of clustering, differences in size and number of clusters detected, and differences in significance and magnitude of associations between FIV or FeLV infections and predictor variables as the level of aggregation changed.

Ecology and predation of free ranging farm cats

 Kitts-Morgan SE, Caires KC, Bohannon LA, Parsons EI, Hilburn KA (2015) Free-Ranging Farm Cats: Home Range Size and Predation on a Livestock Unit In Northwest Georgia. PLoS ONE 10(4): e0120513. doi:10.1371/journal.pone.0120513

This study’s objective was to determine seasonal and diurnal vs. nocturnal home range size, as well as predation for free-ranging farm cats at a livestock unit in Northwest Georgia. Seven adult cats were tracked with attached GPS units for up to two weeks for one spring and two summer seasons from May 2010 through August 2011. Three and five cats were tracked for up to two weeks during the fall and winter seasons, respectively. Feline scat was collected during this entire period. Cats were fed a commercial cat food daily. There was no seasonal effect (P > 0.05) on overall (95% KDE and 90% KDE) or core home range size (50% KDE). Male cats tended (P = 0.08) to have larger diurnal and nocturnal core home ranges (1.09 ha) compared to female cats (0.64 ha). Reproductively intact cats (n = 2) had larger (P < 0.0001) diurnal and nocturnal home ranges as compared to altered cats. Feline scat processing separated scat into prey parts, and of the 210 feline scats collected during the study, 75.24% contained hair. Of these 158 scat samples, 86 contained non-cat hair and 72 contained only cat hair. Other prey components included fragments of bone in 21.43% of scat and teeth in 12.86% of scat. Teeth were used to identify mammalian prey hunted by these cats, of which the Hispid cotton rat (Sigmodon hispidus) was the primary rodent. Other targeted mammals were Peromyscus sp., Sylvilagus sp. and Microtus sp. Invertebrates and birds were less important as prey, but all mammalian prey identified in this study consisted of native animals. While the free-ranging farm cats in this study did not adjust their home range seasonally, sex and reproductive status did increase diurnal and nocturnal home range size. Ultimately, larger home ranges of free-ranging cats could negatively impact native wildlife.

Cat's impact in Idaho

Hansel, T. E. (2015). Update: Pressing Issues--Impacts of Roaming, Stray, and Feral Domestic Cats (Felis catus) on Birds in Idaho.

Outdoor domestic cats (Felis catus) threaten the welfare of birds and endanger the integrity of the ecosystems into which domestic cats are introduced in Idaho.

Spatial ecology of feral cats on San Clemente Island

Bridges, A. S., Sanchez, J. N., & Biteman, D. S. (2015). Spatial ecology of invasive feral cats on San Clemente Island: implications for control and management. Journal of Mammalogy, 96(1), 81-89.

Feral cats, Felis catus, inhabiting San Clemente Island, California, are both predators and competitors of multiple sympatric endemic species. To improve our understanding and management of these invasive predators, we used GPS-equipped radiocollars to track 11 (6F:5M) cats for a total of 3,108 days, resulting in 15,419 GPS locations. Average 100% minimum convex polygon, 95% kernel density, and 50% kernel density estimates were 229, 132, and 33 ha, respectively. The point estimate for average male home-range size was larger than the average for females, but there was substantial variation among individuals of both sexes. Overlap indices indicated similar usage areas during nocturnal and diurnal time periods. Sample size limited our ability to definitively detect habitat preference, but data suggested areas within 50 m of roads were avoided, and that thicker land cover was preferred over open grasslands. Three test collars deployed within active cat home ranges indicated GPS locations were precise, with 96% of locations having < 10-m error estimates, and that horizontal dilution of precision indices were not useful in screening data. Our results describe feral cat spatial ecology on a semiarid island and can be used to inform population estimation, control, and mitigation programs.