1,720,980 research outputs found
Sampling Strategies to Estimate Deer Density by Drive Counts
No full textThe best evaluation of deer density can be achieved by accurate drive counts of deer performed in all the suitable wooded patches of the area of interest. This would provide the true density within drive areas which, in turn, should be akin to the true density within the study area. Because the drive of all these areas is prohibitive, only a subset is usually driven. Results are highly dependent on the subjective choice of the areas. In the present study, an objective design-based approach is considered to select the areas to be driven according to some probabilistic sampling schemes, and deer density in the whole collection of drive areas is estimated by means of some criteria. The schemes should be able to achieve samples of areas evenly spread onto the study region. The criteria should be able to exploit the information provided by the area sizes. Four sampling strategies are considered, together with methods to estimate their precision. They are evaluated by means of a simulation study performed on artificial and real populations. Results from artificial populations determine the best strategies to be used. Results from real populations show that precise estimates are achieved at the cost of sampling 20% of the drive areas. Supplementary materials accompanying this paper appear on-line
A comparative analysis of wolf (Canis lupus) diet in three different Italian ecosystems
No full textTo verify food habit flexibility of wolf populations under different ecological conditions, scats were analysed collected year round in three study areas and diet composition of resident packs was compared. The three study areas, representing Alpine (SV), Apennine (PM) and Mediterranean (CV) ecosystems, are rich in wild ungulates, which differ in number of species and relative abundance; livestock is also present. Wild ungulates were the main source of food, accounting for 89.4%-95.1% of the diet. Livestock, instead, hardly reached 8% of annual mean percent volume in any one area, and only in the Alps did they play a major role in autumn. Other food items constituted less than 5% of annual mean percent volume. Variations in the proportions of use of wild ungulate categories were observed among the study areas, although some patterns of intraspecific selection emerged in each area. Finally, differences both in the relationships between utilisation and availability of preys, and in trophic niche breadth were discussed in relation to environmental features and colonization patterns
Analisi comparativa delle abitudini alimentari del lupo (Canis lupus) in tre diversi ecosistemi italiani
No full text
Serological, molecular and pathological survey of pseudorabies virus in wild boars (Sus scrofa) from central Italy
No full textIntestinal parasites of wild and domestic canids in Val di Cecina (Pi): a comparison among wolves, foxes and dogs.
No full textSerological, molecular and pathological survey of pseudorabies virus in wild boars (Sus scrofa) from central Italy
No full text- …
