Some ecologists say that the domestication of feral cat harms environment or ecosystem, as excessive population of feral cats result in large hunting of small birds and animals in both rural and urban areas.
Feral cats have a considerable effect on the environment, as these cats have put several native animals and species to danger and even death.
Even, people now consider feral cats as the most vicious creatures on small islands. Other species that are vanished on small islands include burrowing bettong and spectacled hare-wallaby. These animals were found once abundant on small islands.
Researchers state that feral cats in the USA, every year, kill large population of animal and bird species, and hundreds of those in Florida. Thus, these cat breeds have great impact on environment as well as wildlife animal species.
This may result in disruption of food chain and limitation of local wildlife populations. In fact, feral cats in countries such as New Zealand and Australia have killed native birds and animals and have damaged the natural flora completely.
In Australia, feral cats have killed several wallabies, thus there is a considerable drop in the population of wallabies over the years. Many ecologists found that feral cats were to blame mostly for the dropping population of rock wallabies in a remote area of tropical Queensland.
Even though feral cats mainly depend on rabbits for their food source, they do little to lower the population, as the population of rabbits is as same as the amount of feral cats in Australia.
Not only the feral cats have a substantial effect on food chain, but they also affect the other local creatures by depleting their sources of food. These include the wedge-tailed eagle, hawks, the eastern quoll, reptiles such as the Lace Monitor and Goanna and the dingoes.
Feral cats eat nearly all those foods that are vital for other local species. Because of such huge population, not only these cats eat all other native species, but also provide nothing for other local species. In most regions, hawks and eagles have had to alter their routine diet to survive due to these cats.
Even, the native cats are in danger. Feral cats more often affect domestic cats such as Quoll. For instance, if feral cats come near female quolls, they become infertile. Here, people cannot help them out, but as there are several feral cats around, the best way to avoid is preventing domestic cats to outside exposure. A recent report study states that several female quolls have already become infertile and their populations are declining day-by-day.
Feral cats also carry certain incurable diseases, which are fatal and harmful to other species, especially for the local marsupials. Toxoplasmosis is the name of one such disease, which causes paralysis, blindness, respiratory disorders, and loss of infantile because of stillbirth and impulsive abortion.
Feral cats are also the carriers of Rabies, a disease affecting not only animals and species, but also the human beings. It is more excruciating and devastating to the whole ecosystem.