Sheep predation: Characteristics and risk factors

Abstract

Predation has always been an important problem in extensive sheep farms, causing serious economic losses to the farmers. Official predation reports have recently been decreasing in the District of Pisa, in spite of the presence of two wolf packs in the area. The aim of the present research was to obtain reliable information on the characteristics of predation and to estimate the effectiveness of existing prevention methods in sheep farms of the southern District of Pisa, in order to set up predictive models for an improved and more focused prevention plan and support interventions by public authorities. On-farm surveys were carried out in 73 semi-extensive sheep farms. Predation events were reported by 75.3% of the farmers. Wolves seemed to be responsible for most of those events, although their actual role could be confirmed only in 34% of cases. Most of the events occurred in spring and 85.1% of them were concentrated during night time. The average number of sheep killed during each attack was 7.05. In 22.3% of cases, the number of sheep killed was ≥ 10. Proximity to protected areas and the presence of thick vegetation cover significantly affected the probability of a farm being subjected to chronic predation. Farm size was significantly higher in those cases. No clear indication about the effectiveness of prevention methods could be obtained from our survey. The results of this investigation highlighted the impact of predation in the Southern District of Pisa and emphasized the need for finding technical and political solutions to this problem. Attention should be focused on large farms, with thick vegetation cover and located close to protected areas. Further investigations should be carried out in order to test the effectiveness of suitable prevention methods in these farms.The title and the running title have been changed, following the reviewer's suggestion.The manuscript (text, figures and tables) has been reviewed again from a native English speaker. We hope that there are no more errors in this new version. All the changes are highlighted in red.Thank you for the quick revision and the useful comments.

Impact of Wolf(Canis Lupus)on Animal Husbandry in an Apennine Province

“…This suggests that the presence of closed shelters for the night or fences is extremely important: this drastically reduces attacks by wolves, even if some attacks happen during the day. Confirming the results of previous studies conducted both in Italy and abroad (Cozza et al, 1996;Mech et al, 2000;Mattiello et al, 2012), our results suggest that the size of the flock is another important risk factor. In fact, predation occurred with significantly higher frequency in smaller farms (5.9% of farms with less than 25 animals vs 48% of the farms with more than 25 animals; P<0.01) and two farms with chronic predation had more than 100 animals.…”

“…This is similar to the average value reported by Ciucci and Boitani (1998), but lower than that observed in other provinces of Tuscany: in Pisa province, for example, the average number of sheep killed during each wolf attack was 7.05, with several surplus killing events , while in the province of Arezzo it was 15 (Gazzola et al, 2008). The adult age class suffers more attacks, in agreement with data reported by other authors (Ciucci and Boitani, 1998;Mattiello et al, 2012). In this study, the killing of approximately 10 lambs in 2010 and 10 in 2011 occurred, but these losses were not formally complained, because these young lambs (less than six months old) had not been identified with ear tags yet.…”

“…The farmers are not favourable to these structures, mainly because of the high cost of installation, but also because of subsequent maintenance costs, consisting essentially of cutting the grass. This phenomenon was also observed in the provinces of Pisa and Florence (Berzi et al, 2008;Mattiello et al, 2012), where many farmers have rejected the adoption of these fences, in spite of the possibility of having them for free.…”

“…In fact, predation occurred with significantly higher frequency in smaller farms (5.9% of farms with less than 25 animals vs 48% of the farms with more than 25 animals; P<0.01) and two farms with chronic predation had more than 100 animals. The susceptibility to attacks of larger flocks can be explained in part by the difficulty of monitoring the large number of animals by the farmer, who usually works alone, or because in these flocks guardian dogs are often numerically insufficient to prevent the attacks (Cozza et al, 1996;Mech et al, 2000;Mattiello et al, 2012).…”

“…Tuscany shows many mountain ranges, related to both the main backbone chain and the secondary chain. Depending on this strategic location at the heart of the Apennines, and on the quantity and quality of the environments suitable for the survival of the species, the wolf is present throughout the region, with differing densities between provinces (Banti et al, 2005;Mattiello et al, 2012).…”