carunculatus rufusater) in Little Barrier Island, New Zea-
land(Gillies& Fitzgerald,2005).Yet therehavebeen fewer
than100cat eradicationsfrom islands(Nogaleset al.,2004;
Campbell et al., 2011) and there are likely thousands of
islands where feral cats negatively impact native verte-
brates (B. Tershy, unpublished data). Thus, more effective
cat eradication techniques are needed, as are guidelines
for selecting islands where cat eradication will have the
largest impact. Our review suggests that cats have nega-
tive impacts on a wide range of native vertebrates, that
endemic island species are particularly vulnerable com-
island mammals may be the most vulnerable, and that
introducedalternate prey species such as mice and rabbits
1. Cats have contributed to a minimum of 14% of all bird,
mammal, and reptile extinctions and the decline of at
least 8% of critically endangered birds, mammals, and
reptiles. Cats can be eradicated from many islands and
our results suggest that the most vulnerable species are
island endemics, particularly mammals and that intro-
duced alternate prey (rodents and rabbits) increase the
impactsof feral cats.
2. Our review undoubtedly underestimated the impact
of cats on native species due to the lack of studies on
numerous islands of the world and on numerous
endangered species particularly in Asia, Indonesia,
Polynesia, and Micronesia.
3. Existing studies suffered from uneven geographic
coverage of vertebrate orders (e.g. clumping of rep-
tile studies in the Caribbean and mammal studies in
the Eastern Paciﬁc) and limited quantiﬁcation of
impacts or controlled experimental design.
4. More research on the impacts of feral cats on island
animals can improve these guidelines and thus
improve the prioritization of islands for cat eradica-
5. More studies are needed that quantify changes in
the survival, reproductive success, or population
size of native vertebrates following cat eradication.
This contribution is dedicated to all who have supplied infor-
mation on the effects of feral cats in all islands worldwide. This
work has received support from the European Union by the
projects CGL-2004-0161 BOS co-ﬁnanced by the Spanish Minis-
try of Science and Education, the DIREN PACA via Life Nature
project (ref. LIFE03NAT/F000105), the French National
Research Agency (ALLIENS project) and the MEDAD (Ecotrop-
ic programme). EB was ﬁnanced by a CR PACA PhD fellow-
ship. Brian M. Fitzgerald made a critical read of this review,
supporting interesting annotations and suggestions. Pedro Jord-
ano made useful comments on the early draft of the manuscript,
and Karl J. Campbell and an anonymous referee did it on its
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