Much ado about nothing: assessing the impact of a problematic rodent on agriculture and native trees

Human-wildlife conflict, especially related to crop losses, dramatically reduces tolerance towards wildlife and hinders conservation efforts. Despite being a protected species, the crested porcupine Hystrix cristata, probably an introduced species to Italy, is recorded as one of the worst agricultural pest and is extensively poached. Tree debarking by this rodent is also reported, although no quantitative information was available before this work. We analysed data on crop damages by crested porcupines from complaints obtained by two areas of Central Italy. As well, data on tree debarking were collected and examined. Our results showed that the crop damage by this species is low, even if it may sporadically account for up to 44 % the overall agricultural loss (mostly to sunflower, onion, melon and watermelon). Higher damages may occur on private small vegetable gardens, particularly on underground storage organs. Even if analysed in a single study area and for only 1 year, tree debarking occurred on less than 6 % of trees, mainly young plants (Fraxinus ornus, Ostrya carpinifolia and Pyrus pyraster), with no tree mortality.