Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation.

We estimated the current size and dynamics of the wolf population in Tuscany and investigated the trends and demographic drivers of population changes. Estimates were obtained by two different approaches: (i) mixed-technique field monitoring (from 2014 to 2016) that found the minimum observed pack number and estimated population size, and (ii) an individual-based model (run by Vortex software v. 10.3.8.0) with demographic inputs derived from a local intensive study area and historic data on population size. Field monitoring showed a minimum population size of 558 wolves (SE = 12.005) in 2016, with a density of 2.74 individuals/100 km2. The population model described an increasing trend with an average annual rate of increase λ = 1.075 (SE = 0.014), an estimated population size of about 882 individuals (SE = 9.397) in 2016, and a density of 4.29 wolves/100 km2. Previously published estimates of wolf population were as low as 56.2% compared to our field monitoring estimation and 34.6% in comparison to our model estimation. We conducted sensitivity tests to analyze the key parameters driving population changes based on juvenile and adult mortality rates, female breeding success, and litter size. Mortality rates played a major role in determining intrinsic growth rate changes, with adult mortality accounting for 62.5% of the total variance explained by the four parameters. Juvenile mortality was responsible for 35.8% of the variance, while female breeding success and litter size had weak or negligible effects. We concluded that reliable estimates of population abundance and a deeper understanding of the role of different demographic parameters in determining population dynamics are crucial to define and carry out appropriate conservation and management strategies to address human-wildlife conflicts.

A Predator on the Doorstep: Kill Site Selection by a Lone Wolf in a Peri-Urban Park in a Mediterranean Area.

The aim of the study was to assess which kill site characteristics were selected by a lone wolf living in a protected Mediterranean coastal area near the city of Pisa, Italy, where both wild and domestic ungulates were available as potential prey. Between 2017 and 2019, we monitored the wolf's predatory behaviour through a combination of camera trapping and active search for kill sites and prey carcasses. The main prey found was the fallow deer (n = 82); only two wild boars and no domestic ungulates were found preyed upon. The features and habitat of kill sites were modelled to test for selection by the wolf. The habitat type of kill site was composed of meadows and pastures (89.3%), woods (7.3%), degraded coastal areas (1.9%), roads and rivers (1.1%), and marshes (0.5%). We calculated their distance from landscape features and ran a binomial generalised linear model to test the influence of such landscape variables. The distance of kill sites from landscape elements was significantly different from random control sites, and a positive selection for fences was found. In fact, the wolf pushed fallow deer towards a fence to constrain them and prevent them from escaping. We also analysed the body condition of predated fallow deer as a percentage of fat content in the bone marrow of the hind legs. Our results revealed the selection of the lone wolf for deer in good body condition. This is a possible outcome of the habitat selection shown by fallow deer in the study area, where fenced open pastures are the richest in trophic resources; therefore, our findings suggest a high efficacy for the lone wolf hunting strategy, but also the adoption of a high risk feeding strategy by deer. This study suggests that a lone predator can take advantage of human infrastructures to maximise its predatory effectiveness.

Retrospective Molecular Survey on Bacterial and Protozoan Abortive Agents in Roe Deer (Capreolus capreolus) from Central Italy

Bacterial and protozoan agents can determine abortion and other reproductive disorders in domestic ruminants, but data regarding their occurrence in wild ruminants are scanty worldwide, including in Italy. The aim of this retrospective study was to verify the occurrence of the main bacterial and protozoan abortive agents in 72 spleen samples previously collected from roe deer (Capreolus capreolus) living in mountain areas of Central Italy. All samples were collected and submitted to DNA extraction for other investigations. Molecular analyses were carried out on the DNA samples to detect Brucella spp., Chlamydia abortus, Coxiella burnetii, Salmonella enterica, Listeria monocytogenes, Neospora caninum, and Toxoplasma gondii. Three (4.16%) roe deer resulted PCR positive for C. burnetii and one (1.38%) for T. gondii. These findings suggest that roe deer living in the investigated areas do not act as important reservoirs of the searched agents. However, the tested animals lived in a closed area without contact with domestic animals that are usually involved in the epidemiology of the investigated pathogens. Monitoring of wild ruminants is pivotal to verify changes in the epidemiological scenario from a One Health perspective, too.

Molecular survey on the presence of arthropod-borne bacteria and protozoans in roe deer (Capreolus capreolus) and ticks from Central Italy.

Environmental changes, due to climatic emergency and to anthropogenic activities severely impact on the epidemiology of vector borne diseases, mostly when transmitted by ticks. The data about the distribution of microorganisms responsible for them in roe deer (Capreolus capreolus) population living in Italy are scanty and completely lacking in Tuscany, so a molecular survey was carried out to estimate the prevalence of some zoonotic tick-borne pathogens in roe deer, and ticks removed from them, living in areas of Central Italy with high risk of arthropod exposure. Spleen samples from 72 roe deer were tested by PCR for Anaplasma phagocytophilum, Borrelia burgdorferi s.l., Francisella tularensis and piroplasms. Moreover, 345 ticks were removed from 65 roe deer, morphologically or molecularly identified and grouped into 162 pools that were submitted to PCR for detecting the same pathogens. Forty-six (63.88%) roe deer were positive for at least one investigated pathogen: 43 (59.72%) for A. phagocytophilum, 2 (2.78%) for Babesia capreoli, 1 (1.39%) for B. burgdorferi, and 1 (1.39%) for Babesia sp. No animals were PCR positive for F. tularensis.  All ticks were identified as Ixodes ricinus. Seventy-six (46.91%) tick pools showed DNA of one or more pathogens: 66 (40.74%) were positive for A. phagocytophilum, 22 (13.58%) for B. burgodorferi s.l., 6 (3.70%) for B. venatorum and 3 (1.85%) for B. capreoli. No pools were positive for F. tularensis. Two or three pathogens were detected in 23 (14.19%) pools.

Female preference and predation risk models can explain the maintenance of a fallow deer (Dama dama) lek and its 'handy' location.

We tested the predictions of three models (female preference; hotspot; predator avoidance) on lek formation in the fallow deer population of San Rossore, Tuscany. We collected behavioural observations in two leks and radiotracking data on 67 deer over 7 years. Two deer sub-populations were present in the northern and southern sides of the area, respectively, the two sectors being delimited by a river and including one lek each. Predictions were tested for one lek (SG), located in the south-side where we set up our 7-year radiotracking program. Data from a second lek (FO, north-side) were used to test those predictions which imply the occurrence of multiple leks in the same population. We showed that the majority of females made one single visit to one lek, only during the rut. The lek was located outside areas of higher female traffic and home range overlap, and females increased home range sizes during the rut to reach it. Twilight routes of females never crossed the lek; instead, females walked atypical routes and at a faster pace to reach the lek and mate. The distance between the two leks was higher than the average diameter of female home ranges, and only one lek was present within female home ranges. Males reached the lek one month before the arrival of females, corroborating that lekking is a female-initiated process (females moving towards large clumped male aggregations) rather than a male-initiated process (males moving towards female hotspots). Our results supported the female preference model, and rejected the predictions of the hotspot model. Also, leks were located far from areas with higher predation risk, supporting the predator avoidance model. The position of lek SG resulted 'handy' at the sub-population level because of the optimal trade-off between travel costs for females to reach it and avoidance of human predators.

Seasonal variation of activity patterns in roe deer in a temperate forested area.

We investigated the activity patterns of a European roe deer (Capreolus capreolus) population living in a forested Apennine area in central Italy, in order to shed light on the environmental and biological factors that were expected to account for the observed activity patterns on daily and yearly bases. Daily and seasonal activity patterns of 31 radio-collared roe deer were assessed through sessions of radio tracking for a total period of 18 consecutive months. Roe deer showed bimodal activity patterns throughout the year, with the two highest peaks of activity recorded at dawn and dusk. Activity patterns of males and females differed during the territorial period (from early spring to late summer), whereas they did not during the nonterritorial period. Most likely, behavioral thermoregulation can be held responsible for variation of daily activity patterns in different seasons. In winter, for instance, activity during the dawn period was significantly higher than in other seasons and daylight activity was significantly higher than at night. Nocturnal activity was highest in summer and lowest in winter. During the hunting season, moreover, roe deer showed lower activity levels than during the rest of the year. The prediction that roe deer would show lower activity levels during full moon nights, when the predation risk was assumed to be higher, was not confirmed by our data. Activity rhythms in roe deer were thus subjected to both endogenous and environmental factors, the latter working as exogenous synchronization cues. Accordingly, in changing environmental and ecological conditions, a circadian cycle of activity could be seen as the result of complex interactions among daily behavioral rhythm, digestive physiology, and external modifying factors.