6 research outputs found
Somatic variability in wild boar (Sus scrofa L.) in different areas of Central Italy
A survey of wild boar shot during two consecutive years (hunting seasons 2002-2004) was carried out in order to evaluate which somatic measurements are most significant in identifying and discriminating among different morphotypes in central Italy. Biometric data from 688 wild boars was collected in three different areas of central Italy, two in Viterbo and one in the Province of Rieti. The following somatic measurements were individually recorded for each specimen: head-body length, height at withers, hind-foot length, ear length, ear-snout distance and ear-shoulder distance. Body weight was registered, and age was estimated from tooth eruption and wear. The animals were divided into three age classes; young (aged less then 12 months), sub-adults (aged between 12 and 36 months), and adults (36 months and older). After a preliminary ANOVA procedure, which did not give satisfactory results, a statistical analysis was performed using a canonical discriminant procedure, given an a priori classification (geographical area) and several quantitative variables (somatic measurements and weight). The separation between areas was estimated calculating the squared distance of Mahalanobis. The data referring to all 688 specimens was subjected to factor analysis. The results of the canonical discriminant analysis highlight the existence of two distinct groups within all three age classes. There is a statistically significant difference between the southern- Maremma (SM) vs the Apennine (A) and sub-Apennine (SA) areas, for young (P<0.0001), sub-adults (P<0.001) and adults (P<0.001). The difference between the A and SA areas was significant only for sub-adults (P<0.05). The first canonical variable account for 92.5, 92.7 and 89.9% of the total variance for the three age classes respectively, but this is unequally correlated with the original variables suggesting that the separation between the two areas is due to differences in conformation rather than in body size. On the basis of the discriminant analysis large part of the animals were correctly categorised in the sampling areas. As regards the factor analysis results for the adult group, the first three common factors are able to explain 78, 92, and 64% of the covariance for the data of the SM, A and SA groups respectively. These results suggest that, for the SM group, a differentiation among morphotypes may be possible on the basis of a few somatic measurements. These results confirm the need for biochemical and genetic studies to identify if the different morphotypes refer to the autochthonous wild boar strain
A nesting site suitability model for rock partridge (Alectoris graeca) in the Apennine Mountains using logistic regression
The rock partridge has undergone a decline throughout its entire distribution area, including the population of the central Italian Apennine Mountains. Areas of suitable habitat for this species have been reduced due to landscape fragmentation and the dynamics of domestic animal and wildlife management. The present study was conducted in the Province of Rieti, Lazio Region. Geograph- ical and land use predictors were evaluated in a GIS environment to identify the most relevant factors influencing the presence of rock partridge during the nesting period. Logistic regression was then imple- mented to create a model, characterised by a good level of adequacy, for predicting rock partridge nesting site habitat characteristics. Correct predictions of presence and absence were made in 65.2% and 98.6% of cases, respectively. The ROC value was 0.771, which is statistically significant (P<0.001). The results show that, on a local scale, slope (log), distance from forests, and the presence of bare rocks were statisti- cally significant factors. On a landscape scale, the percentage of forests, the presence of sparse vegetation (over 60%), and a negative Mean Shape Index (MSI) were found to be statistically significant
A nesting area suitability model (MISN) to estimate the population parameters of Rock Partridge, Alectoris graeca orlandoi, in Rieti and Frosinone Provinces
In the last decades the Rock Partridge has undergone a decline throughout the entire area of distribution. The abundance of Apennine Rock Partridge, Alectoris graeca orlandoi, in the provinces of Frosinone and Rieti has been estimated with the pre-reproductive census technique of playback in the areas suitable for nesting. The methodology for assessing the suitability of the site for nesting of Apennine Rock Partridge was based on a parametric procedure that included the attribution of score to biotic (land use) and abiotic (elevation, slope, etc.) factors producing Andrea Amici 1, Fioravante Serrani 1, Settimio Adriani 2, Bruno Ronchi 1, Marco Bonanni 3 & Riccardo Primi 1 USO DEL MODELLO DI IDONEITĂ€ DI SITO PER LA NIDIFICAZIONE (MISN) PER LA STIMA DEI PARAMETRI DI POPOLAZIONE DELLA COTURNICE APPENNINICA, ALECTORIS GRAECA ORLANDOI, NELLE PROVINCE DI RIETI E DI FROSINONE, AGGIORNATA AL DICEMBRE 2009 Amici, Serrani, Adriani, Ronchi, Bonanni & Primi different layers. The layers obtained were interpolated to obtain a nesting site suitability model for Rock Partridge (MISN). In the province of Rieti the playback census was conducted in the years 2005-2006-2007 obtaining stable population data: 42-45 nesting pairs, and a density of 0.50 to 0.60 and 0.12 to 0.14 pairs/100 ha of land suitable for nesting, in areas where there is a hunting ban and where hunting is permitted respectively. In the province of Frosinone in 2007 were estimated 76 breeding pairs and a density of 0.6 and 0.28 pairs/100 ha in areas of ban hunting and free hunting respectively