We have common, serotine and greater horseshoe bats, otters, rabbits, hedgehogs ( in Cies ) country and common rats , house and country mice, shrews ( in Cortegada ) and also moles, some of them introduced by men such as rats , rabbits and hedgehogs.
We rarely see the otter but it is proved a long time ago, although its presence, reproduction and breeding was doubted, but today it is present in the four archipelagos. In the furnas there are usually small freshwater overflows that become necessary for the use, care and cleaning of salinity attached to the otters.
Rabbits are very abundant and easy to see. They leave traces such as excrements on the roads (brown balls) and the dens that they dig. They suffer from the plague of myxomatosis almost every year usual for a large number of specimens. After all, it is a way of self-regulation of these populations.
Other mammals are wild cats (in Cies and Ons) and the American mink (in Ons and Sálvora) resulting the first ones in the domestic cat in freedom. The second one is a result of the releases and escapes from fur farms in the continent. Both species are harmful to populations of birds and lizards so its presence is fought from the park to reduce and eliminate its impact.
