Predators generate a "landscape of fear" within which prey can minimize the risk of predation by selecting low-risk areas. Depending on the spatial structure of this "landscape", i.e., whether it is ...coarse- or fine-grained, prey may respond to increased risk by shifting their home ranges or by fine-scale redistributions within these ranges, respectively. We studied how wild boar (
Sus scrofa
L., 1758) responded to temporal changes in risk in hunted areas (risky habitat) surrounding a nature reserve (refuge habitat). Animals with home ranges "in contact" with the reserve during the low-risk season were the only ones to shift toward the refuge when the risk increased. These shifts occurred at two temporal scales in response to the increased risk during the daytime and during the hunting season. Whereas animals not influenced by the reserve found food and shelter in forest during the hunting season, shifts to the refuge area were detrimental to the rather scarce forest areas in the reserve. This confirms that spatiotemporal changes in risk are major drivers of animal distribution when predation strongly limits their fitness. Their response is, however, scale-dependent and reflects at the individual level the perceived structure of their "landscape of fear".
Domestic pigs are susceptible to foot and mouth disease virus (FMDV) infection and suffer from severe clinical disease. Our knowledge on the clinical manifestations of FMD in and its transmission by ...wild boars (Sus scrofa) is very limited. During an FMD outbreak in the Golan Heights in 2018, wild boars grazing in close proximity to cattle were observed showing lameness. Infectious FMDV was isolated from throat and heart tissues of two young wild boars with FMD clinical signs. This is the first report of wild boars clinically infected with FMDV in the Middle East.
As one of the most relevant foodborne diseases, it is essential to know the factors related to the transmission, persistence and prevalence of Toxoplasma gondii infection. Eurasian wild boar (Sus ...scrofa) might play a relevant role in T.gondii's life cycle. This species is the most consumed big game animal in Spain and may act as a source of infection if the meat is eaten raw or undercooked or due to cross-contaminations. Additionally, wild boar can act as an excellent bioindicator of T.gondii circulation in the ecosystem, because its natural behaviour leads to exposure to oocysts from the soil when rooting and tissular bradyzoites when scavenging. A total of 1003 wild boar were sampled from 2010 to 2017 in Mediterranean Spain. Blood samples were tested with an indirect ELISA test giving a total of 14.1% (95% confidence interval 12.0–16.4%) positive results. The prevalence was not homogeneous in neither the animals nor the sampled districts. Significant differences were found regarding age, climatic conditions and human space occupancy. Human population aggregation, assessed by Demangeon's index, was identified as an influential factor in T.gondii infection risk. This multiple approach allows us to evaluate local risks for human and environmental contamination.
•Our study maps environmental and human factors related with Toxoplasma gondii's prevalence in wild boar.•1003 wild boar were analized and studied by Demangeon's index, a novel approach to understand disease ecology.•An indirect indicator of cats and Toxoplasma oocysts' environmental presence, linking human behaviour and wildlife infection.
Thailand is one of the last strongholds for tigers Panthera tigris in mainland Southeast Asia. Evidence suggests heterogeneity in tiger presence in a globally important landscape in Eastern Thailand ...is potentially influenced by a complex interaction of prey, human presence and environmental conditions. Understanding these dynamics is of considerable importance for the conservation of tigers both in this landscape and elsewhere in their range. In this study, we examine which factors, among prey, human presence and environmental characteristics, best explain tiger presence in the Dong Phayayen–Khao Yai Forest Complex (DPKY). We collated survey data from 56,214 camera trap nights and evaluated the relationship between tiger presence and a suite of five prey, 11 human presence and eight environmental variables. We then used variance partitioning to discern the degree of variance in tiger presence explained by these factors. We documented strong, positive associations with wild boar Sus scrofa presence and prey richness, and strong, negative associations with human settlement density, public roads and presence of poachers. Environmental characteristics explained a greater relative proportion of variance (19.6%) in tiger presence than prey covariates alone (3.1%), particularly confounded with human presence (31.1%). This suggests that environmental variables, especially when accompanied by anthropogenic factors, could be used to model potential tiger occurrence where other data may be lacking. Our approach may be helpful in providing guidance for prioritizing habitat, evaluating the effect of human presence and identifying key prey to provide a foundation for tiger protection and recovery.
In our study, using extensive camera‐trap survey data and variance partitioning, we evaluated the degree to which prey, human, and environmental characteristics explain tiger presence in the Dong Phayayen–Khao Yai Forest Complex, a tiger landscape of global conservation priority. Environmental variables explained a greater proportion of variance in tiger presence than any other factor in our study, suggesting that environmental variables could be used to effectively model tiger occurrence where other data may be lacking. This approach may be helpful in providing guidance for prioritizing habitat, evaluating the effect of human presence, and identifying key prey to provide a foundation for tiger protection and recovery. Figure: Relative proportion of variance in tiger detections explained by environmental, human, and prey factors and camera trap effort.
The human dimension of wildlife is increasingly addressed in socioecological studies on the growth of some wildlife populations in Europe, which frequently leads to conflicts, particularly when wild ...populations inhabit or reach humanized landscapes. In Europe, ungulates have been increasing in number and distribution, especially the wild boar (
Sus scrofa
). This has been a cause of concern, given the increase in traffic accidents, diseases, and crop damage caused by the wild boar. These impacts could shape people’s perception regarding this species, but sociocultural factors can influence a favorable perception. This study examines people’s perception of the wild boar in Portugal, collecting responses from 1532 individuals, including farmers, hunters, and the general public. Three indexes were created to analyze perception: interest in wildlife, perception of benefits, and perception of damage associated with wild boar. Respondents had, in general, a positive perception of the wild boar. Farmers were more aware of wild boar increasing trends and had a higher damage perception and a lower perception of species benefits. This was expected, considering the increasing damages caused by wild boar to crops. Hunters showed an intermediate perception between the farmers and the general public that mainly highlighted the benefits. This study is valuable in providing data to orientate awareness-raising actions, as well as management strategies to tackle wild boar densities, such as hunting coupled with other methods. It is of the utmost importance the application of compensatory schemes, through the government, as an
end-of-line
measure. Future research should focus on adaptive management involving multidisciplinary teams.
Cystic Echinococcosis (CE) caused by Echinococcus granulosus sensu lato (s.l.) is one of the most important parasitic zoonotic diseases in the world and it represents an important public health and ...socio-economic concern. In the Mediterranean basin, CE is widespread and it is endemic in Italy, with major prevalence in southern areas. Several studies have investigated CE in domestic pigs, however, such data in wild boars are scant. In the last decades the wild boar population in Italy has increased and this ungulate could play an important role in the spreading of CE in the wild. Here we report on the prevalence and fertility rate of hydatid cysts in wild boars that were shot during two hunting seasons (2016–2017) in the Campania region of southern Italy.
For each animal, a detailed inspection of the carcass and organs (lungs, liver and spleen) was performed and when cysts were found, their number, morphology and fertility were determined by visual and microscopic examination. Cysts were classified morphologically as fertile, sterile, caseous and calcified. Protoscoleces and germinal layers were collected from individual cysts and DNA was extracted to identify different strains/genotypes of E. granulosus s.l.
Out of a total of 2108 wild boars 93 (4.4%) were found positive for CE. Infected animals were 45 males and 48 females, aged between 1 and 8 years. The average number of cysts per wild boar was 1.3 (min 1 - max 13). The total number of cysts collected was 123, of which 118 (95.9%) in the liver, 4 (3.3%) in the lungs and 1 (0.8%) in the spleen. Of all analyzed cysts, 70 (56.9%) were fertile and 53 (43.1%) sterile/acephalous. The presence of fertile cysts in 19.4% of CE-positive animals is noteworthy. Overall, molecular diagnosis showed 19 wild boars infected with the pig strain (G7).
Display omitted
•A survey on CE on 2.108 wild boars from southern Italy was performed.•The prevalence of CE was 4.4% with fertility rate of 1.0%.•Echinococcus granulosus G7 genotype was isolated.
To conduct an epidemiological study of hepatitis E virus (HEV) in Japanese wild boars, we collected 179 serum and 162 fecal specimens from wild boars in eight Japanese prefectures; 39 of the serum ...samples (21.8%) were positive for anti-HEV IgG antibodies. RT-qPCR revealed HEV RNA in 11 serum samples (6.1%) and 5 fecal samples (3.1%). We obtained 412 bp of the viral genome sequences of ORF2 from five pairs of serum and fecal samples. All strains were subtype b in genotype 3 (HEV-3b) but separated into different clusters. We determined the entire genome sequence of HEV-3b strain WB0567 using a fecal specimen and isolated this strain by cell culture using PLC/PRF/5 cells. Eleven nucleotide mutations had occurred during virus replication. These results suggest that HEV-3b circulated uniformly among wild boars in Japan. Direct sequencing using a suspected animal’s samples is indispensable for predicting original HEV nucleotide sequences.
We devised a method to detect the classical swine fever virus (CSFV) in tail-wiped swabs from wild boars. The CSFV gene in swabs was detected with high sensitivity using nested real-time polymerase ...chain reaction (PCR), which is a combination of reverse transcription-PCR (RT-PCR) and real-time PCR. We compared CSFV gene detection from boar tissue using the conventional and our tail-wiped swab method. The tail-wiped swab method showed sensitivity and specificity of 100% (26/26) and 98.8% (172/174), respectively compared to the conventional method. Thus, the swab-based CSFV detection method was considered to have detection sensitivity comparable to that of conventional methods. Additionally, we conducted surveillance for CSFV in wild boars on Awaji Island. CSFV was detected in 10.7% (45/420) of samples.
Landscape connectivity is a major factor shaping the spread of pathogens in wildlife populations. By managing connectivity, transmission pathways can be broken and disease spread be contained, ...particularly in the early phases of an outbreak. Having witnessed recent outbreaks of African Swine Fever in free‐ranging wild boar (Sus scrofa) in Belgium, Germany and Italy, offices for disease control are on the alert also in other western European countries.
This study investigates the potential effect of managing landscape connectivity to contain disease spread among free‐ranging wild boar in disparate landscapes. It involves research into (1) the ease with which wildlife corridors can be blocked for wild boar, (2) the connectivity of wild boar habitat and (3) the impact of landscape fragmentation on connectivity management. This is addressed by carrying out GIS analyses and performing graph operations on the wild boar networks in different biogeographical regions of Switzerland.
The results of doing research into the three above‐mentioned objects show that, regarding the first, most wildlife corridors are hard to block for wild boar, because their features or location make fencing difficult. Regarding the second, the wild boar habitat is connected. Opening wildlife passages that are currently under construction may allow wild boar to disperse to hitherto uncolonized areas. Regarding the third, all wild boar networks could be partially decomposed by blocking the easy to block corridors and closing the passages. Network decomposition would be easiest to achieve in the region where the built infrastructure is most abundant. All over Switzerland, the potential epidemic size could be reduced by 25% when blocking the minimal set of corridors and passages that cut the networks to non‐decomposable components.
This study suggests that (a) combining connectivity analysis with fragmentation analysis is key to explaining why a specific measure of disease containment is more effective in one landscape than in the other, (b) complementing the permeability model with a species distribution model is essential to identify connected habitat patches for the species of concern and (c) connectivity metrics should consider also the surface area of occupied habitat patches and relative abundance of the species of concern.
Analytical framework showing (upper part) how the wild boar networks in Switzerland were established from geographical features, (lower part) their representation as matrices according to (left) the wild boar populations and (right) the biogeographical regions as well as (middle) the states of the networks investigated.
The value of shot animals has been determined both on the basis of market pricelist of the Hunting Association of Serbia for the 2021/22 hunting year and according to the structure of animals shot ...per certain game categories obtained in previous research. MATERIAL AND METHODS The research included hunting activity and economically most representative game species managed by a majority of established hunting grounds according to the Law on Game and Hunting (2010) and the Rule Book on the way of establishing hunting grounds and areas (2018) and the Solution on establishing hunting grounds in hunting areas (2020) in Serbia. On the basis of a previous research an average trophy value shown in Table 2 was calculated on the basis of the nine hunting grounds in the territory of Serbia (Baraj evska river, Jadar, Takovo, Dubrava, Klisura, Kamenica, Maj sinj ske mountains, Resava, Krilaš) where 1,184 roe deer trophies were evaluated (Popovic et al., 2023) according to the formula of the International Council for Game and Wildlife Conservation CIC (Beuković and Popovic, 2014; Ristie and Tiodorović, 2009; Trense et al., 1981; Frković, 1989). According to the Law on Game and Hunting (2010) the wild game can be introduced into a hunting ground only if by their introducing the balance between biological equilibrium and biological diversity has not been disturbed.
PDF
