ABSTRACT Mortality due to illegal killing is still today one of the main threats to wolf conserva... more ABSTRACT Mortality due to illegal killing is still today one of the main threats to wolf conservation, and an effective management of the conflict between wolf presence and husbandry is a key element for species conservation. The research was aimed at identifying the farm characteristics and the environmental factors that influence predation, and at formulating predictive models of predation risk. We collected and analysed the data on official predation events that occurred during the period 2005–2012 in an area of the northern Apennines, and on the characteristics of livestock farms recorded at the veterinary services. Furthermore, we mapped the grazing areas used by livestock farms and measured 23 variables of the pastures. Our results showed that the majority of predation events were upon cattle, and that grazing management significantly influences the number of predation events. In particular, the pastures that suffered predation were those in which births occur directly on the pasture, those that had at least one period of free grazing during the year, and cattle farms that were lacking in any preventive methods. The number of killed animals per event was higher for sheep than for cattle and goats and increased progressively during the study period. Predation risk increases if the farms practice free grazing at least for a period during the year, if they are not protected by any preventive method and if the degree of surveillance is regular or constant. The risk of predation also increases with the increasing complexity of pasture shape, the decrease in the percentage of coniferous forest and if the pasture is exposed to the north. The model of predation risk showed that 56.6% of the pastures in the study area are potentially exposed to wolf predation, and it allowed us to identify the grazing areas where it is worthwhile intervening with preventive methods.
ABSTRACT Long-term changes of wolf feeding habits have been recorded in several parts of its Euro... more ABSTRACT Long-term changes of wolf feeding habits have been recorded in several parts of its European range and were related to the increase of wild ungulate populations. An increased use of wild prey often is linked to a decrease of predation on livestock, and consequently it can reduce wolf–human conflict and make for easier predator conservation. We analysed wolf diet from scats collected from 2007 to 2012 in a 927.3-km2 area of the Northern Apennines (Northern Italy) to compare the present diet to that recorded in the late 1980s when the area was colonised by wolves, and to examine short-term changes of wolf feeding habits together with annual and seasonal variations of wild and domestic ungulate selection, possibly related to the increase of wild ungulate abundance. We calculated the availability proportions of wild ungulate species from the presence signs recorded on itineraries and those of livestock species from the data on farms of veterinary services. We identified 17 kinds of prey, pooled into six categories, of which wild ungulates (70%) and livestock (20%) were the most important. During the study period, we observed a reduction in the diet breadth of wolves, to a greater use of wild ungulates, depending on the increase in the availability of wild prey species. Significant seasonal variations were observed in the trophic habits of the wolf, but generally there was a wide use of wild ungulates, especially wild boars. Livestock was mainly used in summer, which corresponds to the period of greatest presence of domestic ungulates on the pastures. Considering the study period, a fast response of wolf feeding habits to the increase of wild ungulate species resulted, together with changes in selection patterns. The change in diet towards a greater use of wild ungulates is an important step in the recovery and conservation of the wolf.
ABSTRACT We investigated the patterns of wild ungulate selection by wolves in an 860 km study are... more ABSTRACT We investigated the patterns of wild ungulate selection by wolves in an 860 km study area of the Northern Apennines (North Italy), in order to detect seasonal variation in wolf diet and changes of feeding habits in relation to the increased abundance of wild ungulates. From June 2007 to May 2008 we collected wolf scats and recorded the signs of presence of wild ungulate species along 25 transects, representative of the different habitat types within the study area. We analysed the scats to identify the main food items used by wolves in each season and we compared the proportions of biomass of wild ungulate species in the diet (use) to those calculated from the signs of presence (availability). We recorded significant seasonal changes in wolf feeding habits, but the main food items were wild ungulates, mainly wild boars, and medium-sized mammals. Livestock (sheep, goats, and calves) were used only in summer and early autumn, during the grazing period, in small quantities. Comparing the current diet of wolves to that recorded in the past in the same study area highlighted significant differences for wild ungulates and livestock, the former being more used nowadays and the latter less. Our study showed that, in the Northern Apennines, the feeding behaviour of wolves has evolved towards a greater use of wild prey, so reducing the impact on livestock and consequently wolf-human conflicts. Moreover, predation by wolves was directed towards the most abundant species of wild ungulates.
We reviewed 20 studies on wolf diet in Italy, to relate the changes in diet composition to the in... more We reviewed 20 studies on wolf diet in Italy, to relate the changes in diet composition to the increase of wild ungulate population in Italy. Researches covered the period from 1976 to 2004 and the whole range of wolves from southern Apennines to western Alps. We used the frequency of occurrence of seven food categories and of the wild ungulate species occurring in the diet. Estimates of wild ungulate populations were obtained from the literature and we extrapolated their trend in the period considered. Differences among geographic areas (south-central Apennines, northern Apennines, and western Alps) were tested by nonparametric multivariate analysis of variance, while the trends of the wild ungulate and livestock use and of diet breadth were analysed by regression and curve-fit analyses. We used the same method to support the relationships between the use and availability of wild ungulates. Wolves preyed on wild herbivores more in the northern Apennines and in the western Alps than in the southern Apennines; the contrary was the case for livestock. Among wild ungulate species, wild boar, roe deer and red deer were the main prey of the wolf. The occurrence of wild ungulates in the wolf diet increased from 1976 to 2004 together with a decrease of livestock; the increase was mainly due to roe deer, red deer and chamois. The results of scat analysis in the province of Genoa showed an increase of the occurrence of wild ungulates from 1987 to 2005, in particular roe deer and fallow deer. Wolves in Italy seem to select wild ungulates over domestic ones where the former are available with rich and diversified guilds and abundant populations.
ABSTRACT Mortality due to illegal killing is still today one of the main threats to wolf conserva... more ABSTRACT Mortality due to illegal killing is still today one of the main threats to wolf conservation, and an effective management of the conflict between wolf presence and husbandry is a key element for species conservation. The research was aimed at identifying the farm characteristics and the environmental factors that influence predation, and at formulating predictive models of predation risk. We collected and analysed the data on official predation events that occurred during the period 2005–2012 in an area of the northern Apennines, and on the characteristics of livestock farms recorded at the veterinary services. Furthermore, we mapped the grazing areas used by livestock farms and measured 23 variables of the pastures. Our results showed that the majority of predation events were upon cattle, and that grazing management significantly influences the number of predation events. In particular, the pastures that suffered predation were those in which births occur directly on the pasture, those that had at least one period of free grazing during the year, and cattle farms that were lacking in any preventive methods. The number of killed animals per event was higher for sheep than for cattle and goats and increased progressively during the study period. Predation risk increases if the farms practice free grazing at least for a period during the year, if they are not protected by any preventive method and if the degree of surveillance is regular or constant. The risk of predation also increases with the increasing complexity of pasture shape, the decrease in the percentage of coniferous forest and if the pasture is exposed to the north. The model of predation risk showed that 56.6% of the pastures in the study area are potentially exposed to wolf predation, and it allowed us to identify the grazing areas where it is worthwhile intervening with preventive methods.
ABSTRACT Long-term changes of wolf feeding habits have been recorded in several parts of its Euro... more ABSTRACT Long-term changes of wolf feeding habits have been recorded in several parts of its European range and were related to the increase of wild ungulate populations. An increased use of wild prey often is linked to a decrease of predation on livestock, and consequently it can reduce wolf–human conflict and make for easier predator conservation. We analysed wolf diet from scats collected from 2007 to 2012 in a 927.3-km2 area of the Northern Apennines (Northern Italy) to compare the present diet to that recorded in the late 1980s when the area was colonised by wolves, and to examine short-term changes of wolf feeding habits together with annual and seasonal variations of wild and domestic ungulate selection, possibly related to the increase of wild ungulate abundance. We calculated the availability proportions of wild ungulate species from the presence signs recorded on itineraries and those of livestock species from the data on farms of veterinary services. We identified 17 kinds of prey, pooled into six categories, of which wild ungulates (70%) and livestock (20%) were the most important. During the study period, we observed a reduction in the diet breadth of wolves, to a greater use of wild ungulates, depending on the increase in the availability of wild prey species. Significant seasonal variations were observed in the trophic habits of the wolf, but generally there was a wide use of wild ungulates, especially wild boars. Livestock was mainly used in summer, which corresponds to the period of greatest presence of domestic ungulates on the pastures. Considering the study period, a fast response of wolf feeding habits to the increase of wild ungulate species resulted, together with changes in selection patterns. The change in diet towards a greater use of wild ungulates is an important step in the recovery and conservation of the wolf.
ABSTRACT We investigated the patterns of wild ungulate selection by wolves in an 860 km study are... more ABSTRACT We investigated the patterns of wild ungulate selection by wolves in an 860 km study area of the Northern Apennines (North Italy), in order to detect seasonal variation in wolf diet and changes of feeding habits in relation to the increased abundance of wild ungulates. From June 2007 to May 2008 we collected wolf scats and recorded the signs of presence of wild ungulate species along 25 transects, representative of the different habitat types within the study area. We analysed the scats to identify the main food items used by wolves in each season and we compared the proportions of biomass of wild ungulate species in the diet (use) to those calculated from the signs of presence (availability). We recorded significant seasonal changes in wolf feeding habits, but the main food items were wild ungulates, mainly wild boars, and medium-sized mammals. Livestock (sheep, goats, and calves) were used only in summer and early autumn, during the grazing period, in small quantities. Comparing the current diet of wolves to that recorded in the past in the same study area highlighted significant differences for wild ungulates and livestock, the former being more used nowadays and the latter less. Our study showed that, in the Northern Apennines, the feeding behaviour of wolves has evolved towards a greater use of wild prey, so reducing the impact on livestock and consequently wolf-human conflicts. Moreover, predation by wolves was directed towards the most abundant species of wild ungulates.
We reviewed 20 studies on wolf diet in Italy, to relate the changes in diet composition to the in... more We reviewed 20 studies on wolf diet in Italy, to relate the changes in diet composition to the increase of wild ungulate population in Italy. Researches covered the period from 1976 to 2004 and the whole range of wolves from southern Apennines to western Alps. We used the frequency of occurrence of seven food categories and of the wild ungulate species occurring in the diet. Estimates of wild ungulate populations were obtained from the literature and we extrapolated their trend in the period considered. Differences among geographic areas (south-central Apennines, northern Apennines, and western Alps) were tested by nonparametric multivariate analysis of variance, while the trends of the wild ungulate and livestock use and of diet breadth were analysed by regression and curve-fit analyses. We used the same method to support the relationships between the use and availability of wild ungulates. Wolves preyed on wild herbivores more in the northern Apennines and in the western Alps than in the southern Apennines; the contrary was the case for livestock. Among wild ungulate species, wild boar, roe deer and red deer were the main prey of the wolf. The occurrence of wild ungulates in the wolf diet increased from 1976 to 2004 together with a decrease of livestock; the increase was mainly due to roe deer, red deer and chamois. The results of scat analysis in the province of Genoa showed an increase of the occurrence of wild ungulates from 1987 to 2005, in particular roe deer and fallow deer. Wolves in Italy seem to select wild ungulates over domestic ones where the former are available with rich and diversified guilds and abundant populations.
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