A feral cat is a cat that lives outdoors and has had little or no human contact. They do not allow themselves to be handled or touched by humans, and will run away if they are able. They typically remain hidden from humans, although some feral cats become more comfortable with people who regularly feed them. Even with long term attempts at socialization, feral cats usually remain fearful and avoidant of humans.
Feral cats often live outdoors in colonies in locations where they can access food and shelter. These colonies are called managed colonies when they are provided with regular food and care by humans. Some animal rescue groups provide care for feral cats by implementing trap-neuter-return programs, feeding the cats, socializing and adopting out young kittens, and providing healthcare.
Attempts to control feral cat populations are widespread, although the techniques differ significantly. Some advocate for trap-neuter-return programs to prevent the cats from continuing to breed; others suggest euthanasia.
The meaning of the term feral cat varies between professions and countries, and is sometimes used interchangeably with other terms such as free-roaming, street, alley, or community cat. Some of these terms are also used to refer to stray cats, although stray and feral cats are generally considered to be different by rescuers, veterinarians, and researchers. Stray cats are socialized cats who no longer live in homes, but could potentially be successfully reintroduced to a home environment.
A 2013 article in the Journal of Feline Medicine and Surgery found that rescuers and veterinarians in the United Kingdom tended to distinguish feral cats from domesticated cats based on traits such as their levels of socialization, ownership, and confinement, and on the amount of fear of, interaction with, and dependence upon humans. They found that rescuers and veterinarians tended to agree that feral cats were cats that had not had much human contact (particularly before eight weeks of age), would try to avoid humans, and would prefer to escape rather than attack a human. However, veterinarians and rescuers disagreed on whether a feral cat would tend to hiss and spit at or attack a human during an encounter, and disagreed on whether adult ferals could potentially be tamed. The article provided a composite definition of a feral cat as a cat that would choose not to interact with humans, could survive with or without human assistance, and would hide or defend itself when trapped rather than allowing itself to be handled.
A survey of rescuers and veterinarians in the United States found that there was no widely accepted definition of a feral cat. Many facilities used waiting periods to evaluate whether a cat was feral by observing whether the cat became less afraid and evasive over time. Other indicators included the cat's response to touch with an inanimate object, and observation of social behavior from the cat in varying environments (in response to human contact, with a human nearby, or when moved to a quieter environment). The American Society for the Prevention of Cruelty to Animals defines community cats as either cats who were born and raised in the wild, or domestic cats who have been abandoned or lost and turned to wild ways in order to survive.
Farm cats (also called barn cats) are cats that live on agricultural properties in feral or semi-feral condition. They primarily live outdoors, usually sheltering in outbuildings. They hunt vermin such as rodents and other small animals that live in or around outbuildings and farm fields.
The need to keep rodents from consuming or contaminating grain crops stored for later human consumption may be the original reason cats were domesticated. They are still commonly kept for the purpose of catching undesired vermin found on farms and ranches, which would otherwise eat or contaminate crops, especially grain or feed stocks.
Some animal rescue organizations maintain farm cat programs, where they place cats in barns whose owners agree to provide basic care for the animals. The cats in these programs are often feral cats who cannot safely be returned to their colonies, or cats who are semi-feral or otherwise difficult to adopt due to behavioral issues.
Ship's cats are typically feral or semi-feral, and were once common features on many trading, exploration, and naval ships. Cats were primarily brought aboard to catch mice and rats, which can cause damage to ropes, woodwork, and eventually as technology progressed, electrical wiring. Rodents also presented a threat to the stores the ship carried, both as cargo and as food for sailors. Rats and mice were also sources of disease, which was dangerous for ships at sea for long periods of time. Cats have been officially banned from some commercial and military fleets, though they are sometimes still kept privately by sailors.
Although scientists do not agree on whether cats were originally domesticated in Egypt or if they were introduced there after domestication, the spread of cats throughout much of the world is thought to have originated in Egypt, where they were popular and effective at controlling mouse populations. Traders from Phoenicia brought them to Europe to control rat populations, and monks brought them further into Asia. Roman armies also helped with the spread, eventually bringing them to England. Since then, cats continued to be introduced to new areas, often by sailors or settlers. Cats are thought to have been introduced to Australia in either the 1600s by Dutch shipwrecks, or the late 1700s by English settlers. These domesticated cats began to form feral populations after their offspring began living away from human contact.
Some behaviors are commonly observed among feral cats, although there is disagreement among veterinarians, rescuers, and researchers on the prevalence of some. In a free-roaming environment, feral cats avoid humans. They do not allow themselves to be handled or touched by humans, and back away or run when they are able to do so. If trapped, they may hiss, growl, bare their teeth, or strike out. They remain fairly hidden from humans and will not approach, although some feral cats gradually become more comfortable around humans who feed them regularly.
Feral cats often live in colonies, groups of feral cats that live together in one territory, often near food sources and shelter. Researchers disagree on the existence, extent, and structure of dominance hierarchies within feral colonies. Different types of hierarchies have been observed in feral colonies, including despotic and linear hierarchies. Some colonies are organized in more complex structures, such as relative hierarchies, where social status of individual cats can vary on their location, the time of day, or the activity the cats are engaged in (particularly feeding and mating).
When a human decides to care for a feral colony, it is often called a managed colony. The care given can include regularly supplying food and water to the cats, providing shelters, helping with trap-neuter-return programs, providing continued veterinary care, finding foster homes for cats that can be socialized for eventual adoption, and working to educate people who live in the neighborhood.
Feral kittens can be trapped and socialized, then adopted into a home. The age at which a kitten becomes difficult to socialize is not agreed upon, but suggestions generally range from seven weeks to four months of age. Although older cats can sometimes be socialized, it is a very long and difficult process, and the cat rarely becomes friendly and may remain fearful.
In a 2013 study of participants from the United Kingdom, rescuers tended to be more willing than veterinarians to attempt to tame adult feral cats. Veterinarians tended to be more opposed to this practice, with some expressing concerns for the welfare of such a cat in a home environment. In a 2010 study of veterinarians and rescuers in the United States, 66% of respondents had socialization programs for kittens, and 8% for adult cats.
Diet and predatorsEdit
Feral cats primarily subsist on food scavenged from garbage when it is available to them. They also eat animals they kill, and carcasses of animals already dead. Feral cats living in managed colonies are fed cat food by their caretakers.
Domesticated and feral cats have been observed to prey on a wide variety of both vertebrates and invertebrates. Cats typically prefer smaller animals with body weights under 100 grams (3.5 oz), particularly mammals, birds, and lizards. A meta-analysis of studies of cat diet found that cats preyed on over 1,000 species. The analysis found house mice, European rabbits, black rats, house sparrows, and common blackbirds were some of the most commonly observed prey species.
Feral cats in Australia prey on a variety of wildlife. In arid and semi-arid environments, they eat mostly introduced European rabbits and house mice. In arid environments where rabbits do not occur, native rodents are taken. In forests and urbanized areas, they eat mostly native marsupials (particularly the common ringtail possum) and rodents.
Life span and survivalEdit
Without human assistanceEdit
Without human assistance, feral kittens are expected to have a high death rate, with approximately 50% dying within the first year.:45 Of cats who survive kittenhood, the average life span of a feral cat without human care is less than two years
However, adult feral cats without human assistance have been found in surprisingly good condition. In Florida, a study of feral cats admitted to a trap-neuter-return (TNR) program concluded that "euthanasia for debilitated cats for humane reasons is rarely necessary". A further study of over 100,000 community cats (feral and stray) admitted to TNR programs in diverse locations of the U.S. resulted in the same 0.4% rate of euthanasia for debilitating conditions. The body condition of feral cats entering a TNR program in Florida was described as "generally lean but not emaciated". However, many community cats had suffered from parasites such as fleas and ear mites before entering TNR programs.
With human assistanceEdit
Feral cats in managed colonies can live long lives. A number of cats in managed colonies in the U.K. died of old age.:522 In the U.S., the last cat in a managed colony in Washington, D.C. died at age 17, and Zorro, the last cat of a colony at the Merrimack River in Newburyport, Massachusetts, died in 2009 at age 16.
A long-term study of a trap-neuter-return (TNR) program on a university campus in Central Florida found that, despite widespread concern about the welfare of free-roaming cats, 83% of the cats studied had been present for more than six years, with almost half first observed as adults of unknown age. The authors compare this result to a 1984 study that found the mean life span for domesticated cats was 7.1 years.
Feral cats, as with all cats, are susceptible to diseases and infections including rabies, bartonellosis, toxoplasmosis, plague, parasites, feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), rickettsial diseases, and feline respiratory disease complex (FRDC, a group of respiratory illnesses including feline herpesvirus type 1, feline calicivirus, Chlamydia felis, and Mycoplasma felis).
Feline leukemia virus and feline immunodeficiency virus belong to the Retroviridae family, and both cause immunosuppression in cats, which can increase their susceptibility to other infections. Research has shown that the prevalence of these viruses among feral cat populations is low and is similar to prevalence rates for owned cats in the United States.
Researchers studying 553 feral cats in Northern Florida in the United States tested them for a number of infections that could be detrimental to feline or human health. The study found the most prevalent infection to be Bartonella henselae, the cause of cat-scratch disease in humans, with 33.6% of the cats testing positive. Feline coronavirus was the next most common infection, found in 18.3% of the cats, although they noted that the antibody levels were low in most of the cats who tested positive, and concluded that the cats they tested did not appear to be a greater risk for shedding the virus than pet cats. Researchers studying 96 feral cats on Prince Edward Island in Canada found that feline roundworm was the most common infection in cats in that colony, afflicting 34% of cats. This was followed by Toxoplasma gondii, which was detected in 29.8% of cats, although only one cat of the 78 for whom fecal samples were available was shedding T. gondii oocysts. They did note that most fecal samples collected indicated the presence of one intestinal parasite, with some samples indicating the presence of multiple parasites.
Transmission to humansEdit
The Center for Disease Control and Prevention has warned about the rabies risk associated with feral cats. With 16% of people infected with rabies from exposure to rabid cats, cats have been the primary animals responsible for transmission of the virus to humans in the United States since the efforts to control rabies in dogs in the 1970s. In 2010, there were 303 rabid cats reported within the United States. Although some colony management programs involve administering rabies vaccines, the need to revaccinate every few years makes this challenging to maintain. Furthermore, lack of documentation can mean that contact with vaccinated feral cats may still require post-exposure treatment.
The study of feral cats on Prince Edward Island warned of "considerable zoonotic risk" for transmission of intestinal parasites. Although the authors noted that their study did not provide evidence for great risk associated with T. gondii in cats, they advised that the risk should still be considered, as the infection in humans can cause significant health problems, and cats who are not otherwise transmitting the infection can begin shedding the virus in times of stress.
Distribution and habitatEdit
Feral cats live on all continents except for Antarctica. The worldwide feral cat population is estimated to be at least 100 million. The United States' feral cat population is estimated at 60 million, Australia's at 12 million, and Britain's at one million.
Cats are found on many remote islands, such as the Hawaiian Islands, where they are an invasive species. Based on microsatellite genetic tests it was determined that these cats have a mainly European ancestry. This can be attributed to their travel on ship trading routes in the 19th century.
Some locations have become known for their feral cat populations, such as the Japanese island of Aoshima. The multiple, managed, feral colonies at the Colosseum in Rome exceed 250 cats. Other notable colonies include the Canadian Parliamentary Cats, and the cats of Jerusalem.
Most feral cats have small home ranges, although some are more transient and travel long distances. The home ranges of male feral cats, which are generally two or three times larger than those of female cats, are on average under 10 hectares (25 acres), but can vary from almost 300 hectares (740 acres) to under 1 hectare (2.5 acres). This variance is often due to breeding season, access to females, whether the cat is neutered, age, time of day, and availability of prey.
Control and managementEdit
Trap-neuter-return (TNR) involves trapping feral cats, spaying or neutering them, and then returning them to the place where there were originally trapped. When neutered, the cats receive vaccinations against rabies and other medical care, such as dental care and parasite treatment. TNR programs are prevalent in several countries, including England, Italy, Canada, and the United States, supported by many local and state governments. Various long-term studies have shown that TNR is effective in stopping reproduction and reducing the population over time. TNR results in fewer complaints, as nuisance behaviors diminish following neutering,:16 and the quality of life of the cats is improved.:1359 The practice is reported to save money:294 and garner more public support and better morale than efforts that involve killing cats.:297:49
The International Companion Animal Management Coalition advocates for TNR as a humane method of controlling feral cat populations. In the U.S., the practice is endorsed by the Humane Society of the United States and the National Animal Control Association. While the United States Department of Defense does not formally advocate TNR, it provides information to military installations on how to implement TNR programs, with the main message that population control programs must be humane.
In 2011, an Australian study emphasised the need to monitor the effects of culling programs after infrared cameras found that the culling of feral cats led to an increase in feral cat populations in the culled areas. It was thought that only dominant cats were being baited and trapped during such operations. After the removal of dominant cats, there was an influx of subordinate animals to the area which unlike the dominant cats, did not venture into the traps. Within a year cat numbers in culled areas stabilised to original numbers.
Effects on wildlifeEdit
Cats hunt small prey, such as rodents and birds. Free-ranging cats kill one to four billion birds and six to 22 billion mammals annually in the contiguous states of the United States. 
Sometimes feral cats kill non-native pests. Feral cats have been intentionally introduced to some areas as a pest control strategy. In the 1800s, thousands of cats were introduced near settlements in Australia that had developed near gold dig sites and farms as an attempt to manage populations of mice, rabbits, and rats.
Hybridisation with wild felidsEdit
Feral cats have interbred with wildcats to various extents throughout the world, the first reported case occurring more than 200 years ago. The significance of hybridisation is disputed. Older documentation suggests that the wildcat was a separate species from the domestic cat, but modern genetic analysis has shown that the domestic cat is a domesticated version of the near-eastern wildcat. In some locations, high levels of hybridisation have led to difficulties in distinguishing a "true" wildcat from feral domestic and domestic hybrid cats, which can complicate conservation efforts. Some researchers argue that "pure" wildcats do not exist anymore, but others dispute this.
One study in Scotland suggests that while "true" Scottish wildcats are unlikely to exist, the current wildcat population is distinct enough from domestic cats to be worth protecting, genetics research is still underway as part of the Wildcat Haven project in Scotland, which has reported success protecting wildcats from hybridisation with widespread trap-neuter-return work. Wildcat populations' notable gene introgression exists also in Italy, Hungary, Spain and Portugal.
- Gosling, Lara; Stavisky, Jenny; Dean, Rachel (2013). "What is a feral cat?: Variation in definitions may be associated with different management strategies". Journal of Feline Medicine and Surgery. 15 (9): 759–64. doi:10.1177/1098612X13481034. PMID 23966002.
PROPOSED DEFINITION: A feral cat is proposed by this study to be a cat that is unapproachable in its free-roaming environment and is capable of surviving with or without direct human intervention, and may additionally show fearful or defensive behaviour on human contact.
- "Feral and Stray Cats—An Important Difference". Alley Cat Allies. Retrieved 9 March 2016.
- Slater, Margaret R.; Miller, Katherine A.; Weiss, Emily; Makolinski, Kathleen V.; Weisbrot, Lila A. M. (1 August 2010). "A survey of the methods used in shelter and rescue programs to identify feral and frightened pet cats". Journal of Feline Medicine and Surgery. 12 (8): 592–600. doi:10.1016/j.jfms.2010.02.001. ISSN 1098-612X. PMID 20460192.
- "A Closer Look at Community Cats". ASPCA. Retrieved 26 December 2015.
- Department of Sustainability, Environment, Water, Population and Communities (2011). The Feral Cat (Felis Catus) (PDF) (Report). Commonwealth of Australia.
- Department of Agriculture and Fisheries (March 2015). Feral cat (PDF) (Report). The State of Queensland.
- Wastlhuber, Joan (1991). "History of domestic cats and cat breeds". In Pedersen, Niels C. Feline Husbandry: Diseases and Management in the Multiple Cat Environment. Goleta, CA: American Veterinary Publications, Inc. ISBN 978-0939674299.
- Geller, Jon (5 February 2016). "Geller: The care, keeping and importance of barn cats". Coloradoan. Retrieved 9 March 2016.
- Frye, Elizabeth (October 20, 2015). "Barn Cat Placement Program: A Simple Shelter Solution". Huffington Post. Retrieved September 30, 2017.
- "Cats in the Sea Services". U.S. Naval Institute. Retrieved 9 March 2016.
- "How domestic cats spread". The Cat Encyclopedia. New York, NY: Dorling Kindersley. 16 June 2014. p. 19. ISBN 9781465419590.
- Dickman, Chris R. (May 1996). Overview of the Impacts of Feral Cats on Australian Native Fauna (PDF) (Report). Australian Nature Conversation Agency and University of Sydney. Archived (PDF) from the original on 4 March 2016.
- Alger, Janet M.; Alger, Steven F. (2003). Cat Culture: The Social World of A Cat Shelter. Philadelphia, PA: Temple University Press. ISBN 978-1-4399-0772-6.
- "Outdoor Cats: Frequently Asked Questions". The Humane Society of the United States. 8 January 2015. Retrieved 30 October 2015.
- Crowell-Davis, Sharon L.; Curtis, Terry M.; Knowles, Rebecca J. (1 February 2004). "Social organization in the cat: A modern understanding". Journal of Feline Medicine and Surgery. 6 (1): 19–28. doi:10.1016/j.jfms.2003.09.013. ISSN 1098-612X. PMID 15123163.
- Voith, Victoria L.; Borchelt, Peter L. (September 1986). "Social Behavior of Domestic Cats". Compendium on Continuing Education for the Practising Veterinarian. 8 (9): 637–646.
- Bonanni, Roberto; Cafazzo, Simona; Fantini, Claudio; Pontier, Dominique; Natoli, Eugenia (2007-11-01). "Feeding-order in an urban feral domestic cat colony: relationship to dominance rank, sex and age". Animal Behaviour. 74 (5): 1369–1379. doi:10.1016/j.anbehav.2007.02.029.
- "The 7 Steps of TNR". Neighborhood Cats. Archived from the original on 2 January 2017. Retrieved 1 January 2016.
- "Socialized Cat Guide". Alley Cat Allies. Retrieved 30 October 2015.
- "Stray and Feral Cats". ASPCA. Retrieved 30 October 2015.
- "Biology and Behavior of the Cat". Alley Cat Allies. Retrieved 27 December 2015.
- Lepczyk, Christopher A.; Lohr, Cheryl A.; Duffy, David C. (2015). "A review of cat behavior in relation to disease risk and management options". Applied Animal Behaviour Science. 173: 29–39. doi:10.1016/j.applanim.2015.07.002.
- "Colony Care Guide". Alley Cat Allies. Retrieved 27 December 2015.
- Plantinga, Esther A.; Bosch, Guido; Hendriks, Wouter H. (1 October 2011). "Estimation of the dietary nutrient profile of free-roaming feral cats: possible implications for nutrition of domestic cats". British Journal of Nutrition. 106 (Supplement S1): S35–S48. doi:10.1017/S0007114511002285. ISSN 1475-2662.
- Prugh, Laura R.; Stoner, Chantal J.; Epps, Clinton W.; Bean, William T.; Ripple, William J.; Laliberte, Andrea S.; Brashares, Justin S. (2009). "The Rise of the Mesopredator". BioScience. 59 (9): 779–791. doi:10.1525/bio.2009.59.9.9.
- Keim, Brandon (4 May 2015). "The Dingoes Ate My Kitten". WIRED. WIRED. Retrieved 28 December 2015.
- Levy JK, Gale DW, Gale LA, JK; Gale, DW; Gale, LA (2003). "Evaluation of the effect of a long-term trap-neuter-return and adoption program on a free-roaming cat population". J. Am. Vet. Med. Assoc. 222 (1): 42–6. doi:10.2460/javma.2003.222.42. PMID 12523478.
- "A Closer Look at Community Cats". ASPCA. Retrieved September 30, 2017.
- Scott, K. C.; Levy, J. K.; Crawford, P. C. (2002). "Characteristics of free-roaming cats evaluated in a trap-neuter-return program". Journal of the American Veterinary Medical Association. 221 (8): 1136–8. doi:10.2460/javma.2002.221.1136. PMID 12387382.
- Wallace, J. L.; Levy, J. K. (2006). "Population Characteristics of Feral Cats Admitted to Seven Trap-Neuter-Return Programs in the United States" (PDF). Journal of Feline Medicine & Surgery. 8 (4): 279–84. doi:10.1016/j.jfms.2006.02.004. PMID 16603400.
- Scott, K. C.; Levy, J. K.; Gorman, S. P.; Newell, S. M. (2002). "Body Condition of Feral Cats and the Effect of Neutering". Journal of Applied Animal Welfare Science. 5 (3): 203–13. doi:10.1207/S15327604JAWS0503_04. PMID 12578741.
- Levy, J. K.; Crawford, P. C. (2004). "Humane strategies for controlling feral cat populations". Journal of the American Veterinary Medical Association. 225 (9): 1354–60. doi:10.2460/javma.2004.225.1354. PMID 15552308.
- Remfry, J (1996). "Feral cats in the United Kingdom" (PDF). Journal of the American Veterinary Medical Association. 208 (4): 520–3. PMID 8603900.
- "Trap-Neuter-Return Effectively Stabilizes and Reduces Feral Cat Populations". Alley Cat Allies. Retrieved 9 March 2016.
- "Advocates report success with trap, neuter, return approach to stray cats". LA Times Blogs - L.A. Unleashed. 29 September 2009. Retrieved 9 March 2016.
- Nassar, R.; Mosier, J.E.; Williams, L.W. (February 1984). "Study of the feline and canine populations in the greater Las Vegas area". American Journal of Veterinary Research. 45 (2): 282–287. PMID 6711951.
- Levy, Julie K.; Gale, David W.; Gale, Leslie A. (1 January 2003). "Evaluation of the effect of a long-term trap-neuter-return and adoption program on a free-roaming cat population". Journal of the American Veterinary Medical Association. 222 (1): 42–46. doi:10.2460/javma.2003.222.42. ISSN 0003-1488. PMID 12523478.
- Roebling, A. D.; Johnson, D.; Blanton, J. D.; Levin, M.; Slate, D.; Fenwick, G.; Rupprecht, C. E. (2014-06-01). "Rabies Prevention and Management of Cats in the Context of Trap–Neuter–Vaccinate–Release Programmes". Zoonoses and Public Health. 61 (4): 290–296. doi:10.1111/zph.12070. ISSN 1863-2378. PMID 23859607.
- Lee, I. T.; Levy, J. K.; Gorman, S. P.; Crawford, P. C.; Slater, M. R. (2002). "Prevalence of feline leukemia virus infection and serum antibodies against feline immunodeficiency virus in unowned free-roaming cats" (PDF). Journal of the American Veterinary Medical Association. 220 (5): 620–2. doi:10.2460/javma.2002.220.620. PMID 12418520.
- Luria, Brian J.; Levy, Julie K.; Lappin, Michael R.; Breitschwerdt, Edward B.; Legendre, Alfred M.; Hernandez, Jorge A.; Gorman, Shawn P.; Lee, Irene T. (1 October 2004). "Prevalence of infectious diseases in feral cats in Northern Florida". Journal of Feline Medicine and Surgery. 6 (5): 287–296. doi:10.1016/j.jfms.2003.11.005. ISSN 1098-612X. PMID 15363760.
- Stojanovic, Vladimir; Foley, Peter (2011-09-01). "Infectious disease prevalence in a feral cat population on Prince Edward Island, Canada". The Canadian Veterinary Journal. 52 (9): 979–982. ISSN 0008-5286. PMC . PMID 22379197.
- Weise, Elizabeth Weise (18 August 2013). "Feral cat colonies could pose rabies risk, CDC says". USA TODAY. Retrieved 10 March 2016.
- "Wild Side of Cats". Nat Geo WILD. Retrieved 2016-03-30.
- McLamb, Eric (27 August 2013). "The Global Impact of Feral Cats". Ecology Global Network. Retrieved 17 March 2016.
- Koch, Katrin; Algar, Dave; Schwenk, Klaus (2016-08-01). "Feral Cat Globetrotters: genetic traces of historical human-mediated dispersal". Ecology and Evolution. 6 (15): 5321–5332. doi:10.1002/ece3.2261. ISSN 2045-7758. PMC . PMID 27551385.
- "It's raining cats and tourists on a Japanese island". Reuters. 2015-03-03. Retrieved 2016-03-29.
- "Cat Empire: Moggies outnumber humans on Aoshima Island in Japan, in pics". Telegraph.co.uk. Retrieved 2016-03-29.
- Hamilton, Jill (30 July 2007). "Blair and the stray cats of Jerusalem". The Jerusalem Post. Archived from the original on 13 July 2011. Retrieved 25 August 2009.
- How to Help Community Cats: A step-by-step guide to Trap-Neuter-Return. Bethesda, MD: Alley Cat Allies. 2015. p. 2. Archived from the original on 17 October 2014.
- Kortis, Bryan (2013). Neighborhood Cats TNR Handbook (PDF) (2 ed.). Neighborhood Cats. p. 115.
- Natoli, Eugenia; Maragliano, Laura; Cariola, Giuseppe; Faini, Anna; Bonanni, Roberto; Cafazzo, Simona; Fantini, Claudio (2006). "Management of feral domestic cats in the urban environment of Rome (Italy)". Preventive Veterinary Medicine. 77 (3–4): 180–5. doi:10.1016/j.prevetmed.2006.06.005. PMID 17034887.
- "Feral Cat Organizations". The Humane Society of the United States. 21 October 2009. Archived from the original on 22 November 2009. Retrieved 3 March 2016.
- Hughes KL, Slater MR; Slater (2002). "Implementation of a feral cat management program on a university campus" (PDF). Journal of Applied Animal Welfare Science. 5 (1): 15–28. doi:10.1207/S15327604JAWS0501_2. PMID 12738586.
- Slater, Margaret R.; Shain, Stephanie (2005). "Feral cats: An overview" (PDF). The State of the Animals. Washington, D.C.
- "Humane Cat Population Management Guidance" (PDF). International Companion Animal Management Coalition. 2011.
- HSUS Position Statement: Trap-Neuter-Return (TNR) (PDF), The Humane Society of the United States, 20 March 2006
- "Taking a Broader View of Cats in the Community" (PDF). Animal Sheltering. September–October 2008. Archived from the original (PDF) on 22 July 2011.
- Kozaryn, Linda D. "'Trap, Neuter, Return,' Cat Lovers Urge". United States Department of Defense. Archived from the original on 14 July 2015. Retrieved 21 November 2010.
- Kozaryn, Linda D. "Cat Herding on the Military Range-DoD Advocates Humane Cat Control". United States Department of Defense. Archived from the original on 14 July 2015. Retrieved 21 November 2010.
- Salleh, Anna (7 April 2015). "Culling cats 'may do more harm than good'". ABC. Retrieved 4 September 2016.
- Loss, Scott R.; Will, Tom; Marra, Peter P. (2012-09-06). "Article number: 1396". The impact of free-ranging domestic cats on wildlife of the United States (Report) (Nature Communications 4, ed.). NATURE COMMUNICATIONS. Retrieved 2016-08-20.
Here we conduct a systematic review and quantitatively estimate mortality caused by cats in the United States. We estimate that free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually. Un-owned cats, as opposed to owned pets, cause the majority of this mortality. Our findings suggest that free-ranging cats cause substantially greater wildlife mortality than previously thought and are likely the single greatest source of anthropogenic mortality for US birds and mammals.
- Driscoll, C. A.; Menotti-Raymond, M.; Roca, A. L.; Hupe, K.; Johnson, W. E.; Geffen, E.; Harley, E. H.; Delibes, M.; Pontier, D.; Kitchener, A. C.; Yamaguchi, N.; O'Brien, S. J.; MacDonald, D. W. (2007). "The Near Eastern Origin of Cat Domestication". Science. 317 (5837): 519–523. doi:10.1126/science.1139518. PMID 17600185.
- European wildcat (Felis silvestris grampia) Arkive.org
- "CSG Species Account: European Wildcat". Cat Specialist Group. 1996. Archived from the original on 8 March 2013. Retrieved 7 January 2016.
- Genetic diversity and introgression in the Scottish wildcat. Molecular Ecology (2001) 10: 319–336. Archived 17 May 2008 at the Wayback Machine.
- (Herald Scotland 'Haven to Save the Wildcat from Total Extinction')
- Domestic gene introgression into wildcat populations in Europe. Petsaspests.blogspot.com.es. Retrieved on 2015-11-01.
|Wikimedia Commons has media related to Feral cats.|
- A feral cat advocacy organization's explanation of feral cats Stray Cat Alliance
- Feral cat control in the UK
- Study of the feral cats in Portsmouth Naval Dockyard, UK with photos and scientific papers
- List of Humane Societies and Rescue Groups With TNR Programs Alley Cat Rescue