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Feral domestic dogs are efficient wild ungulate hunters in many parts of the world. This has not been confirmed in Mediterranean ecosystems. However, if feral dogs can predate upon wild Mediterranean ungulates, they can also do so upon livestock. Therefore, to more realistically understand human-wolf conflict in areas where wolves and feral dogs ov...
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... feral dog study group was composed of medium- sized dogs (20-30 kg in weight). These animals ( Fig. 1) probably escaped from one of the hunting beats for big game hunting in the adjacent hunting estates. The dogs were not always found inside the estate but entered by climbing through holes in the fence or jumping it, mainly along the north-western side of the property. We undertook driven transects over the entire estate (39.9 km) ...
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... In this sense, better control of feral dogs in the Monterredondo sector associated with increased human activity, park rangers, and visitors, probably contributes to the higher deer density in this sector than in La Paila. Separately, according to Duarte et al. (2016), the presence of feral dogs reduces the diversity and abundance of wild animals in natural areas, and whitetailed deer is one of the species most affected by the presence of feral dogs (Bergman et al. 2009). Therefore, controlling feral dog herds in the protected area is essential for the conservation of white-tailed deer. ...
Wildlife population density is affected by resource availability, predators and competitors, and anthropogenic stressors. Its analysis and the factors affecting it are important for conservation, use, or population control. Based on estimates of density and population parameters, together with niche modeling, previous studies considered that the white-tailed deer population at the Chingaza National Natural Park (NNP) is undergoing exponential growth due to the marginal influence of factors regulating its abundance, such as predators. The aim of this study was to evaluate the population density and age structure of the white-tailed deer in the Chingaza NNP, Colombia. To evaluate the population density and age structure of white-tailed deer in the Monterredondo and La Paila sectors of the Chingaza NNP, 10 transects were installed with circular plots in each. These were visited twice; in each visit, we collected all deer pellet groups, measuring each pellet to estimate its volume. Population density was calculated using the Eberhardt and Van Etten method and the semi-automated PELLET procedure using FSC and FAR techniques; the age structure was estimated by k-means and fuzzy clustering analyses. With the FAR technique, the estimated deer density was 2.09 ind/km2 in Monterredondo and 0.94 ind/km2 in La Paila. With PELLET, these values were 0.37 ± 0.4 ind/km2 for Monterredondo and 0.16 ± 0.2 ind/km2 for La Paila. The proportion of age classes (adult, juvenile, and fawn) was 1:0.29:0 for Monterredondo and 1:0.57:0.04 for La Paila. The population density of white-tailed deer in two sectors of the Chingaza NNP is not homogeneous, but shows temporal and spatial variations. Population density has decreased versus reports from previous studies in this same area, with the highest deer abundance recorded in 2004, mostly in the Monterredondo sector. The proportion of age classes suggests that the population is stable, as the largest proportion of individuals corresponds to the adult stage
... In the absence of natural predators within the forests, feral dogs have emerged as potential predators ( Figure 1a). Specifically, in habitats where prey density is high and feral dogs employ a pack hunting strategy, predation rates escalate (Duarte et al. 2016). Younger deer, such as fawns and yearlings, are particularly vulnerable targets for feral dogs due to their relative ease of capture. ...
... The dogs' approach involves harassing, chasing, and diverting the young from their mothers before preying upon them (Muro et al. 2011). Similar instances of depredation by feral dogs on Mediterranean deer have been documented in southern Spain (Duarte et al. 2016). ...
The chital, Axis axis, constitutes one of Nepal's six deer species and maintains a closed population within the forest of the Institute of Forestry, Hetauda Campus. Presently, the chital population faces a range of challenges, prompting a comprehensive study encompassing population status, habitat preference analysis, and threat assessment. We utilized the pellet group count method on 74 systematic random sample plots (4×4m) within a 100×100 m grid for population estimation. Pellet presence/absence in predetermined habitat characteristics was analyzed to assess habitat preferences. Concurrently, a relative threat ranking method from household interviews was employed to evaluate existing threats. The study revealed a total chital population estimate of approximately 141 individuals, with a population density of 190 individuals per km 2. Their habitat preference showed an affinity towards areas abundant in Sal and riverine forests, along with an inclination towards locations further from roads within the forested areas. Primary threats to the chital population encompassed attacks from feral dogs, illegal hunting, and habitat degradation mainly due to invasive alien plant species. This study shows that with effective management of the feral dogs, mitigation strategy to control illegal hunting with the help of local authorities, and improving the habitat conditions concerning their preferences, the chital population has the potential to continue growing in the coming years.
... This is particularly relevant in rural areas, where wildlife is more abundant and accessible. Free-ranging dogs can capture wild species, such as brown hares Lepus europaeus, roe deer Capreolus capreolus, and wild boars Sus scrofa (Krauze-Gryz and Gryz 2014; Duarte et al. 2016;Wierzbowska et al. 2016), increasing the predatory pressure on these prey. They may also pose a direct threat to other carnivores through the spread of diseases, and potential hybridisation with wolves (Vanak and Gompper 2009;Lescureux and Linnell 2014). ...
... Their depredation on livestock species, such as domestic sheep (Ovis aries), has been reported throughout European landscapes from the northern regions such as Sweden (Sundqvist et al. 2008), Estonia (Plumer et al. 2018), andPoland (Wierzbowska et al. 2016), to the southern like Spain (Echegaray and Vilà 2010) and Italy (Mattiello et al. 2012;Magrini 2014;Fabbri et al. 2018). Due to livestock depredation events, dogs can contribute to escalate the conflict between wolves and humans, as losses can be wrongly attributed to wolves (Echegaray and Vilà 2010;Duarte et al. 2016), increasing the hostility towards the species and jeopardising the effectiveness of conservation programs (Boitani et al. 2015). ...
... We found low frequencies of sheep and mustelids, and no evidence of birds despite the great availability of poultry farming in some regions. Overall, our results are in line with previous studies where dogs were found to predate on both larger and smaller prey, such as wild boars and brown hares (Krauze-Gryz and Gryz 2014; Duarte et al. 2016;Wierzbowska et al. 2016). This seems to point to a great ability in surviving in both domestic and non-domestic conditions, making dogs resilient competitors. ...
Livestock depredation is a common cause of human-carnivore conflicts. In Portugal, free-ranging dogs are increasingly abundant and overlap endangered Iberian wolf territories, with reports of livestock depredation. However, the lack of awareness about dogs’ possible role as predators leads to bias against wolves in cases of damages. Our goal was to assess and compare wolf and free-ranging dog’s diet composition at southern wolf range in Portugal, to offer insights on dogs’ predatory role on livestock and its implications for the conservation of an endangered wolf subpopulation. We assessed diet composition from 107 to 95 genetically confirmed wolf and dog scats, respectively, and complemented the analysis with data from 40 attacks on livestock with successful genetic predator assignment. Scat analysis highlighted goats as the most consumed dog prey in all analysed regions, with lagomorphs, small mammals, and wild boars as second most consumed in each region, respectively. Wolves mainly relied on goats and wild boars in the west, whereas in the central region they mostly fed on birds. The dietary overlap between both canids was very high (Pianka’s index O = 0.93), showing potential for competition. Additionally, we found that dogs were the sole predators detected in most attacks (62%). Our findings highlight dogs’ role as predators of livestock, and possibly also wild species, posing a further challenge to wolf conservation. Alongside adequate husbandry practices, we emphasise the need for a stronger enforcement of the legislation on dog ownership and an effective management of the stray population to reduce human-wolf conflict.
... Furthermore, it has been shown that the distance to human settlements was the most critical factor in the abundance and conservation of the S. oculatus in Central Mexico, suggesting the importance of domestic carnivore predation near settlements (Tobajas et al., 2020). Although the abundance of free-living dogs in Spain can be considered lower compared to Mexico (Sykes et al., 2020), and no studies have evaluated the potential impact on squirrels species, it has been documented impacts on wildlife (Duarte et al., 2016;Mill an et al., 2011). These data show that a conservation problem probably exists for many preys and mesocarnivore species due to the high abundance of feral and free-ranging dogs in many areas worldwide. ...
Small mammals show variations in activity patterns due to the use of resources and the risk of predation. However, in the case of tree squirrel species, the factors that affect their activity patterns are poorly studied. We used camera trapping to investigate the activity patterns of three different squirrel species of the genus Sciurus, two species of squirrel (Sciurus aureogaster and S. oculatus) from Mexico and one from the Iberian Peninsula (S. vulgaris). In addition, we compared their activity patterns with the potential predator community and their most important predators (Mexico: gray fox Urocyon cinereoargenteus, ringtail Bassariscus astutus, Opossum Didelphis virginiana; Spain: red fox Vulpes vulpes, pine and stone marten Martes spp.), and with feral and free‐ranging dogs (Canis lupus familiaris). We evaluated the predation risk by the carnivore community on the squirrels when they descend to the ground by studying their temporal overlap and observing if the squirrels have different activity patterns adjusted to the carnivore community in each study area. The results showed that the three species of squirrels consistently descended to the ground during the day, showing a variable maximum peak of activity between 8:00 and 12:00 h. Temporal overlap of activity patterns of the three species with the carnivore community was low (Δ = 0.12–0.36), same as with the main predators (Mexico: gray fox Δ = 0.14–0.21, ringtail Δ = 0.08–0.09, opossum Δ = 0.06–0.07; Spain: red fox Δ = 0.39, martens Δ = 0.22). However, temporal overlap of activity patterns with the domestic dog was moderate‐high in the three squirrel species (Mexico Δ = 0.55–0.88, Spain Δ = 0.79). These results show that the species of the genus Sciurus have adjusted their activity patterns of ground use to reduce predation risk by wild predators but not with feral and free‐ranging dogs, something which can pose a serious conservation problem for these species.
... CGNP harbors a stable population of makhor (n=2856), as compared to other sites in potential habitats of Chitral district . The habitats where the prey density is high and the feral dogs adopt pack strategy (Figure 4), results in high predation rates (Duarte et al., 2016). ...
... The highest number of yearling predations in CGNP reveals that these feral dogs are similar in hunting patterns to other wild canids, i.e. spotted hyenas (Crocuta crocuta) and African wild dogs (Lycaon pictus) (Duarte et al., 2016). As compared to adult animals, fawns and yearlings are easy and effortless prey for feral dogs. ...
... Their strategy is to harass, chase, and distract the young's from their mothers ( Figure 5), and prey on them (Muro et al., 2011). Similar depredation results by feral dogs on Mediterranean deer have been reported from southern Spain (Duarte et al., 2016). ...
Feral dogs are well-organized hunters of ungulates in many parts of the world, causing great damage to wildlife populations and ultimately to the ecosystem. In Pakistan, the impacts of feral dogs on the wildlife have not been documented yet. In a period of fifteen years (2006-2020), feral dogs have killed hundreds of threatened markhor in Chitral gol national park (CGNP), Pakistan. Despite direct predation other impacts including disturbance and competition with other natural predators, could compromise conservation and management efforts. The population of feral dogs seems to have been increased with the increase of dumping sites by communities. Our findings suggest that there are pressing needs of controlling the feral dogs population and eradicating them from the core zone of CGNP and surrounding buffer communities. Conventional culling of dogs should be coupled with modern techniques like castration and sterilization. Communities should be educated regarding the clean environment, proper disposal of home wastes and, biodiversity conservation
... Alternatively, the presence of free-ranging dogs (Canis lupus familiaris) in the area are considered a potentially serious threat to free-ranging sika deer (Jeng, 2003). As a non-native predator, feral dogs can still prove efficient hunters of wild ungulates (Duarte et al., 2016;Vanak and Gompper, 2009), especially in fragmented environments close to human settlements (Manor and Saltz, 2004). Both domesticated and feral dogs were occasionally observed chasing deer over the course of this study. ...
... It is possible that a relatively unstable food supply and local climatic conditions may have played a role in this differential. Prior investigations of wild cervids elsewhere have underscored the importance of direct predation as a likely factor in high newborn mortality (Linnell et al., 1995;Long et al., 1998;Kilgo et al., 2012;Conner et al., 2015;Nelson and Woolf, 2016;Duarte et al., 2016;Warbington et al., 2017). Although potential large native predators, such as Formosan clouded leopards and Formosan black bears, are either extinct or aren't sympatric with these free-ranging deer herds, respectively, free-ranging dogs may still be an important factor in fawn mortality. ...
The Formosan sika deer was declared extinct in the wild in Taiwan around 1969. In 1994, a series of reintroductions was initiated in Taiwan’s Kenting National Park. Today a wild population is established in the core area of the Park, and even continues to expand. Between October 2016 to March 2018, we used Unmanned Aerial Vehicles (UAV) to survey the herd composition of the sika deer in the Shuiwaku Grassland, a forest-grassland mosaic habitat inside the park. We completed a total of 56 early morning surveys (range: 2–7 per month) during the study period. The photographs and videos collected by UAV were used to identify the age and/or sex of each individuals recorded, and to generate data on deer group size, sex ratio, age-group ratio for each herd, and solitary animals. Overall, we cumulatively detected 394 non-independent deer groups comprised of 4732 individuals, and an additional 130 solitary animals. We found that outside of the rutting season (February–September), adult females remained in the adjacent forest the majority of the time. When females moved into the grassland, they formed small-stable groups with young deer (average size: 6.7 ± 4.5 during the post-rutting season; 6.3 ± 3.2 during the calving season). Males either occupied mixed sex groups (average size: 18.0 ± 9.1 during the post-rutting season; 13.8 ± 7.3 during the calving season), or formed bachelor groups (average size: 5.6 ± 4.3 during the post-rutting season; 5.7 ± 3.8 during the calving season) in the open grassland during this same period. During the territorial rut, the proportion of solitary adult males increased significantly to 24.2 ± 15.4%, whereas females also formed gregarious but unstable mixed sex groups with males (average size: 17.0 ± 12.0). Although we observed the first newborns in the open grassland in August (2017), the ratio of fawns to adult females was highest (56.8%) in October, suggesting that this may be the optimal time to conduct annual birth rate surveys. Overall, we found sexual segregation was present in the Formosan sika deer largely driven by sex-based differences in habitat preference, and the non-random assortment of sexes in response to their reproductive status.
... Even the mere presence of feral dogs can deter the use and habitation of an area by wildlife (Lenth et al. 2008) and can have deleterious effects on the breeding success of native species such as ungulates (Gingold et al. 2009). Feral dogs, besides directly killing wildlife species, are thought to harass or chase potential prey species such as fallow deer (Duarte et al. 2016), which may result in increased stress and energetically costly behavior for the fallow deer population (Lenth et al. 2008). ...
Presence of humans and domestic animal species are a common threat to wildlife in protected areas. Wildlife habitat has a particularly strong human presence in the Mediterranean Basin where human population density is high. However, relatively little is known on the interaction and impact of humans on wildlife in much of the Mediterranean region. In this study, we recorded the interactions among several important wildlife species, humans, and domestic animals in a forested Mediterranean landscape in southern Turkey using camera traps. We sought to understand how the presence of humans and domestic animals such as feral dogs (Canis familiaris) and livestock impacted the behavior of the main wildlife species in the region such as caracal (Caracal caracal), fallow deer (Dama dama), and wild boar (Sus scrofa). A total of 4209 photographs from 9 species were captured over a 154-week period. Data were analyzed for both monthly and daily co-occurrences among species using multivariate and univariate techniques. Cluster analyses revealed that while human, wild boar, and fallow deer co-occupied the same area and time, other wildlife species avoided areas used by humans, feral dogs, and livestock which tended to co-occur. Regression analyses revealed that caracal inhabited the same areas as wild boar and European hare (Lepus europaeus), but avoided areas visited by humans and fallow deer on a daily basis. These results suggest that while humans and feral dogs inhabit the same area as wildlife in the region, wildlife species including top predators such as caracal avoid localities recently visited by humans and feral dogs. As a consequence, increasing human activity and feral dog populations has the potential to impact foraging, resting, and hunting behavior of local wildlife and poses a threat to the continued existence of these species in the area.
... During this study, there were incidents where dogs were found chasing nilgai females or fawns even though the larger males were abundant. This pattern of killing ungulates made them easy prey for average sized dogs (Duarte et al. 2016) and this scale of prey selection is comparable with that of wolves (Smith et al. 2004). ...
There is an information gap on biodiversity effects of land use and land cover (LULC) dynamics of agrarian landscapes. Such data are essential for policy making and species management in agro-ecosystems. Thus, changes in LULC inside the Abohar wildlife sanctuary and its eco-sensitive zone were investigated using LISS-III satellite images from 2003 to 2016. The area under cropland witnessed a 3.6% increase, whereas wastelands significantly declined by 4.3%. Further, the impact of LULC dynamics on nilgai (Boselaphus tragocamelus) was determined through mortality distribution in the sanctuary from 2012 to 2017. The spatio-temporal distribution pattern of mortality revealed that a total of 336 nilgai died during the six years studied. Free-ranging feral dogs, in conjunction with fencing and road accidents, were the major factors involved in nilgai casualty. Fatalities were clustered in regions with significant LULC change. The results confirmed that intensified development and reuse of derelict agricultural fields disturbed nilgai ecology and habitat use pattern. Human-wildlife conflicts in agrarian landscapes are an increasing concern and should be managed following identification of sensitive areas.
... Only a few studies have examined intercanine width of several carnivore species (Murman et al. 2006;Foust 2010); however, we could find nothing published on Mexican wolves, or focused explicitly on comparing the overlap of intercanine width between species. Predation by feral dogs is a worldwide problem (e.g., Echegaray and Vilà 2010) and sometimes is misidentified as wolf predation (Caniglia et al. 2013;Duarte et al. 2016). Feral dogs are common throughout Arizona and thus are an important consideration when investigating predation incidents. ...
... Competition between feral dogs and wild carnivores is The shaded gray area depicts the density curve for feral dogs and the degree of overlap between any 2 density curves is provided in Table 2. highest in areas where human-derived food is limited and where feral dogs rely more on wild resources (Vanak and Gompper 2009). Feral dogs will attack livestock and native ungulates (Bergman et al. 2009;Young et al. 2011;Duarte et al. 2016;Wierzbowska et al. 2016). Thus, the high degree of overlap is important because it demonstrates the potential for predation by feral dogs to be confused with that by native predators, especially other canids such as Mexican wolves, and again points to the importance of using additional evidence for classifying kills made by predators. ...
... Given the high degree of overlap, this poses a risk for mistaken identity of Mexican wolves in depredation investigations. As other studies have shown, wolves are often implicated in depredation cases where feral dogs were responsible (Echegaray and Vilà 2010;Caniglia et al. 2013;Duarte et al. 2016). ...
Mexican wolves (Canis lupus baileyi) share their range with a number of sympatric carnivores, many of which are a concern to livestock producers because they can prey on livestock. Determining which predator species is responsible for killing livestock is important for determining appropriate management actions and for the conservation of Mexican wolves. A variety of information can be used to decipher which carnivore species was responsible for making a kill, and mandibular (upper) and maxillary (lower) intercanine width measurements (i.e., bite mark analysis) can aid this process. No research has been conducted to validate the usefulness of bite mark analysis; thus, we used dentition measurements from Mexican wolves, coyotes (Canis latrans), feral dogs (Canis familiaris), bobcats (Lynx rufus), mountain lions (Puma concolor), and gray foxes (Urocyon cinereoargenteus) and an overlap coefficient to evaluate the degree of overlap in intercanine width between these species. We found that larger carnivore species had greater overlap than smaller carnivores, feral dogs overlapped widely with all the medium-to-large carnivores, and upper and lower intercanine width measurements provided similar information. Our data indicated that when investigating livestock depredations for Mexican wolves, bite mark analyses should be evaluated along with additional forensic evidence due to the overlap between many of the carnivore species, and that measurements between 28 and 35 mm have the greatest uncertainty because this range overlaps with feral dogs, mountain lions, and coyotes.
... Only a few studies have examined intercanine width of several carnivore species (Murman et al. 2006;Foust 2010); however, we could find nothing published on Mexican wolves, or focused explicitly on comparing the overlap of intercanine width between species. Predation by feral dogs is a worldwide problem (e.g., Echegaray and Vilà 2010) and sometimes is misidentified as wolf predation (Caniglia et al. 2013;Duarte et al. 2016). Feral dogs are common throughout Arizona and thus are an important consideration when investigating predation incidents. ...
... Competition between feral dogs and wild carnivores is The shaded gray area depicts the density curve for feral dogs and the degree of overlap between any 2 density curves is provided in Table 2. highest in areas where human-derived food is limited and where feral dogs rely more on wild resources (Vanak and Gompper 2009). Feral dogs will attack livestock and native ungulates (Bergman et al. 2009;Young et al. 2011;Duarte et al. 2016;Wierzbowska et al. 2016). Thus, the high degree of overlap is important because it demonstrates the potential for predation by feral dogs to be confused with that by native predators, especially other canids such as Mexican wolves, and again points to the importance of using additional evidence for classifying kills made by predators. ...
... Given the high degree of overlap, this poses a risk for mistaken identity of Mexican wolves in depredation investigations. As other studies have shown, wolves are often implicated in depredation cases where feral dogs were responsible (Echegaray and Vilà 2010;Caniglia et al. 2013;Duarte et al. 2016). ...
Mexican wolves (Canis lupus baileyi) share their range with a number of sympatric carnivores, many of which are a concern to livestock producers because they can prey on livestock. Determining which predator species is responsible for killing livestock is important for determining appropriate management actions and for the conservation of Mexican wolves. A variety of information can be used to decipher which carnivore species was responsible for making a kill, and mandibular (upper) and maxillary (lower) intercanine width measurements (i.e., bite mark analysis) can aid this process. No research has been conducted to validate the usefulness of bite mark analysis; thus, we used dentition measurements from Mexican wolves, coyotes (Canis latrans), feral dogs (Canis familiaris), bobcats (Lynx rufus), mountain lions (Puma concolor), and gray foxes (Urocyon cinereoargenteus) and an overlap coefficient to evaluate the degree of overlap in intercanine width between these species. We found that larger carnivore species had greater overlap than smaller carnivores, feral dogs overlapped widely with all the medium-to-large carnivores, and upper and lower intercanine width measurements provided similar information. Our data indicated that when investigating livestock depredations for Mexican wolves, bite mark analyses should be evaluated along with additional forensic evidence due to the overlap between many of the carnivore species, and that measurements between 28 and 35 mm have the greatest uncertainty because this range overlaps with feral dogs, mountain lions, and coyotes.
