Cat impact on wildlife

Submitted by editor on 19 August 2014.

Do domestic cats have any impact on the wildlife around them? Or do they supplied food prevent from hunting themselves? Find out more in Ferreira et al's study "Domestic cat predation on Neotropical species in an insular Atlantic Forest remnant in southeastern Brazil" in Wildlife Biology. Below is their own ummary of the study.

Although considered as pets, domestic cats have greater behavioral flexibility, which allow them to adapt to various environments in an extraordinary way.

By presenting an opportunistic predation behavior, feeding on a variety of very diverse items, this way we can consider cats as generalist hunters. For this reason, they may have a strong impact of predation on small mammals, birds, reptiles, amphibians, insects, among others. Thus, introducing this species in natural environments, as well as permission of their free access to these areas, can bring strong impact on the local fauna. Several studies conducted in different parts of the world show that in island environments, the presence this predator ends up negatively influencing the survival of some species, which can further aggravate the situation. However, for Brazilian natural environments, little is known about this dynamic.

Our research group has been developing an extensive study whose objective is: to know the possible impacts of this feline, on an island remnant of Atlantic Forest, located on the southern coast of São Paulo - Brazil, to prove mitigation measures to address the problem.

This fragment, a Conservation Unit: Environmental Protection Area Ilha Comprida, belonging to the largest still remaining fragment of the Atlantic Forest of Brazil, the “Serra do Mar”. The IUCN - International Union for Conservation of Nature - classified this region as the third environment importance for the South Atlantic marine productivity.

Since 2009, our team has been conducting research involving methods such as radio telemetry, specifically to check the distances that these animals go in this area of the Atlantic Forest, as well as analysis of the diet of this species through stool samples collected in the region.

The results of this last line of study (see our article in Wildlife Biology), show that even those pets, having a food provided by their owners, in situations where their owners allow access to outside areas; they can exercise this activity on different species, from insects to small vertebrates.  Once they find a wealth of stimuli in this biome of great diversity and are still motivated by their natural hunting behavior. In some cases, these cats can kill even animals proportionally large compared to its size, such as, the big-eared opossum (Didelphis aurita), a species of Brazilian marsupial, as observed during the analysis of the diet of these cats on Ilha Comprida coastal southern state of São Paulo.

Well hunt they do, look here...(video by the authors)