License to Kill? Domestic Cats Affect a Wide Range of Native Fauna in a Highly Biodiverse Mediterranean Country

Abstract

Amongst domestic animals, the domestic cat, Felis catus, is widely considered to be one of the most serious threats to wildlife conservation. This is particularly evident for island ecosystems, as data for mainland countries are often lacking. In Italy, the European country that is richest in biodiversity, cats are very popular pets. In this work, we aimed at assessing the potential spectrum of wild vertebrates that may be killed by free-ranging domestic cats, and we considered our results within the context of their conservation status and IUCN threat category. We collected data on the impact of cats both through a citizen science approach (wildlife predations by 145 cats belonging to 125 owners) and by following 21 of these 145 cats for 1 year and recording all of the prey they brought home. Domestic cats may kill at least 207 species (2042 predation events) in Italy; among those, 34 are listed as "Threatened" or "Near Threatened" by the IUCN and Italian Red Lists. Birds and mammals such as passerines and rodents were reported to be the groups most commonly killed by free-ranging cats. When considering this diet in functional trait space, we observed that the class occupying the largest functional space was that of birds, followed by mammals, reptiles, and amphibians. Thus, the largest impact was on the functional structure of mammal and bird communities. The use of a collar bell did not affect the predation rate of cats, and the number of prey items brought home decreased with increasing distance from the countryside. We provided strong evidence that free-ranging domestic cats may seriously affect the conservation of threatened and non-threatened wildlife species, which are already suffering from population declines due to other causes, e.g., habitat loss. The mitigation of the impacts of domestic cats on wildlife requires dissemination projects promoting responsible cat ownership, as well as a restriction of free-ranging behavior, particularly at nighttime.

First detection ofBursaphelenchus abietinusandB. andrassyiin Italy

“…The effect of five variables was assessed on the number of species of Bursaphelenchus detected in our 778 sampling events through generalized linear models (cf. Mori et al., 2019), conducted through the R software (version 3.5.1., R Foundation for Statistical Computing) packages lme4 (Bates, Maechler, Bolker, & Walker, 2014) and MuMIn (Barton & Barton, 2019). Only data from 2016 to 2019 were considered since in 2015 no parameters were collected.…”

Domestic cats and their impacts on biodiversity: A blind spot in the application of nature conservation law

“…mice, voles, shrews, squirrels, stoats, rabbits and bats), 44 bird species, four reptile and three amphibian species and some invertebrates (Woods, McDonald, & Harris, ). To provide another example, a recent citizen science survey in Italy rendered records of 2,042 animals killed by 145 cats, involving no less than 207 different species (Mori et al, ). Whereas most cat prey tends to consist of small animals, domestic cats have been documented to prey on medium‐sized animals weighing up to 4 kg (e.g.…”

“…A recent Italian study provided further ‘strong evidence that free‐ranging domestic cats may seriously affect the conservation of [various] wildlife species, which are already suffering from population declines due to other causes, e.g. habitat loss’ (Mori et al, ).…”

“…As an interpretive analysis of the Directives in light of CJEU case law shows (Trouwborst & Somsen, ), the Court's broad interpretation of the term ‘deliberate’—as encompassing unwanted but accepted side effects—brings the act of allowing domestic cats to roam free within the scope of the various prohibitions. For instance, western green lizards Lacerta viridis/bilineata and agile frogs Rana dalmatina are listed in Annex IV of the Habitats Directive, and are distinctly prone to predation by domestic cats (Mori et al, ). The same is true, to provide some further examples, of many bat species (Ancillotto, Serangeli, & Russo, ; Ancillotto et al, ), with all Microchiroptera species listed in Annex IV; and certain dormouse Gliridae species (Cortens & Verbeylen, ), most of which are in Annex IV.…”

Evidence for Citation Networks in Studies of Free-Roaming Cats: A Case Study Using Literature on Trap–Neuter–Return (TNR)

“…The ultimate aim of such programs is to reduce or eliminate populations of unowned cats with minimal use of euthanasia, thereby mitigating the problems they cause. The topic is important because free-roaming cats, owned or otherwise, may hunt or otherwise disturb wildlife [ 15 , 16 ], spread disease to wildlife, pet cats or humans [ 17 , 18 ], hybridise with native felids in some locations [ 19 ], cause general nuisance by fighting, spraying and fouling gardens [ 20 ], and suffer poor welfare outcomes themselves through untreated trauma or ingestion of hazardous substances [ 21 ]. Thus measures to reduce or eliminate unowned cat populations are undertaken globally, with due attention to the specific needs and wishes of individual communities (e.g., [ 22 ]).…”