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1.
In the period of August 2013 to September 2015, we collected and measured the body weight of 246 red fox (Vulpes vulpes) carcasses collected during hunts. A portion of these red foxes (n = 153) was originally from habitats they shared with the golden jackal (Canis aureus), while the other portion (n = 93) had almost no contact with this species. We analyzed the body weight of red foxes from both areas according to age (adult-cub) as well as gender. We have found that the younger animals that live sympatrically with the golden jackal weigh less than those from the golden jackal-free territory regardless of gender. In the case of adult red foxes, the habitat-related differences between body weight were found to be insignificant. These results suggest that the high level of nutritional niche overlap between sympatric red fox and golden jackal could affect the body weight of juvenile red foxes.  相似文献   

2.
We investigated the seasonal spatial and temporal co-occurrence of three carnivore species in Liguria region (NW Italy)—the red fox (Vulpes vulpes), the European badger (Meles meles) and the wolf (Canis lupus)—using the information provided by camera-trapping monitoring. Data were collected from January 2013 to January 2015 by positioning camera traps in 200 sample stations. During 3479 trap days, we collected 1048 independent videos of target carnivore species, which revealed a general spatial coexistence among carnivores with some differences in seasonal occurrence of species. The red fox and the European badger showed temporal segregation, as their activity patterns suggested a differential use of night-time in all seasons. Activity patterns of the red fox and the wolf revealed moderate-high overlap and similar density distributions in all seasons except during winter. Coexistence between these species may be allowed by temporal segregation during winter and spatial segregation during spring. Finally, results regarding the European badger and the wolf suggest a moderate temporal segregation with a marked avoidance effect for the European badger induced by the presence of tracks left by wolves. Programmes aimed at carnivore conservation, and management should treat the entire guild, as it has been demonstrated that populations of different carnivores interact with each other in complex ways and that fine-scale mechanisms regulating carnivore assemblage influence different aspects of natural communities.  相似文献   

3.
We have conducted a study between May and August 2013 to understand the dietary spectrum of two canid species: Tibetan wolf (Canis lupus chanco) and Red fox (Vulpes vulpes) in one of the most inhospitable landscape of the world. Ladakh is characterized by harsh environmental conditions and low primary productivity and therefore animal populations, particularly of large and medium sized herbivores are also low and sparsely distributed. This in turn poses a challenge to the survival of predators. We have attempted to investigate the ways by which the two sympatric canid species are optimizing feeding for their survival in an environment where there is scarcity of wild prey base. Scats of the two species were collected from Chiktan and Rangdum valleys and undigested food remnants were identified. The dietary spectrum of Tibetan wolf was composed of six prey species (2 wild and 4 livestock species). The share of livestock species in the diet was maximum (RO: 62.0%). The Red fox being an opportunistic feeder consumed 19 forgeable items, including small and medium sized mammals, birds, reptiles, insects, plant material, eggs, stones and debris. The livestock species contributed maximum to the diet of Red fox (RO: 22.9%). The dietary niche breadths of both species were more or less similar (0.53 and 0.58) and indicating a generalist feeding behavior. Both the species are surviving in the same environment with a dietary overlap of 0.60. The given information is expected to aid further studies in Indian Trans-Himalaya.  相似文献   

4.
Strategies to evaluate and monitor elusive mammal species require the development of genetic techniques and their application to unambiguous biological material for ecological and genetic studies. In order to assess cytochrome c oxidase subunit II gene inter- and intraspecific variations, we compared sequences from different Neotropical canids and domestic dogs. We developed a primer pair to amplify a 154-bp fragment of this gene and a species-specific multiplex TaqMan? assay for accurate identification of two native fox species occurring in sympatry in South America, the crab-eating fox (Cerdocyon thous) and the pampas fox (Lycalopex gymnocercus). The assays can also distinguish domestic dogs (Canis lupus familiaris) from both wild foxes. The use of different fluorescent reporter dyes for species identification in a multiplex probe PCR-RT assay reduces labor and costs. The methodology presented in this study demonstrates an efficient approach to enable high-performance analysis and represents a reliable cost-effective tool for molecular ecology research to monitor the wild canid populations by noninvasive genetic sampling. This standardized assay will allow large-scale high-throughput analyses in a routine and reliable way.  相似文献   

5.
An outstanding sample of Canis etruscus has been found within the faunal assemblage from the early Pleistocene site of Pantalla (Italy), which is referred to the early late Villafranchian. Canis etruscus appeared in Europe about 2 Ma ago. It is regarded as an important taxon for biochronology, as its first occurrence (the “wolf event”) has been used to define one of the Villafranchian faunal turnovers. The discovery of four crania from Pantalla prompted a revision of C. etruscus, in order to better describe its cranial morphology. Since early studies, the distinction between C. etruscus and the coeval C. arnensis has been based mainly on mandibular traits. For this reason, our study is aimed at highlighting differences in craniodental characters between the two species. Canis arnensis has been conventionally considered a jackal-like dog, while C. etruscus is regarded as a wolf-like dog. Consequently, we decided to use jackals for comparison, in addition to C. lupus. Although the jackal group has been traditionally considered as quite homogenous (different species are partially sympatric and similar in both size and ecology), recent genetic studies demonstrate that jackals are not monophyletic. Considering the model offered by extant species, our goal is to delineate the degree of intra- and interspecific variability among the basal forms of the genus Canis.  相似文献   

6.
The raccoon dog (Nyctereutes procyonoides) is an East Asian Canid that has been introduced in Europe. Introduction of alien species is an increasing conservation issue. We examined the diet of a recently established raccoon dog population in Denmark by analysing stomach content in 249 carcasses collected in 2008–2016. Raccoon dog diet was compared to the diet of native badger (Meles meles) and red fox (Vulpes vulpes) in Denmark. The most common food for raccoon dogs were invertebrates (frequency of occurrence, FO 69%), small mammals (FO 68%), birds (FO 41%), fruits (FO 38%), amphibians (FO 36%) and carrions (FO 34%). The occurrence of invertebrates was highest during spring and summer, while fruits, cereals and carrions were eaten most often during autumn and winter. As expected, raccoon dog shared the major food categories with badger and red fox, but generally, it had a wider dietary niche. Overall, dietary overlap between raccoon dog and badger was 0.74 (Pianka index, Ojk). The dietary overlap with red fox was relatively high in all seasons, peaking in summer (Ojk 0.87) and dropping in winter (Ojk 0.79). Despite the dietary overlap between the alien racoon dog and native red fox and badger, the species may coexist due to partitioning of feeding habitats and/or because the red fox is limited by other factors, e.g. diseases and anthropogenic activities. The introduced raccoon dog seems to fit a dietary niche between badger and red foxes in human-dominated landscapes in north-western Europe.  相似文献   

7.
The snow leopard Panthera uncia coexists with the wolf Canis lupus throughout most of its distribution range. We analysed the food habits of snow leopards and wolves in their sympatric range in the Karakoram mountains of Pakistan. A total of 131 genotyped scats (N?=?74, snow leopard; N?=?57, Tibetan wolf) were collected during the cold periods (i.e. winter and spring) of 2011 and 2012 in the Hushey valley. Large mammals, i.e. livestock and ibex, accounted for 84.8 and 83.1% of the diet (relative frequency) of the snow leopard and the wolf, respectively. Domestic prey was the staple of the diet of both snow leopards (66.6%) and wolves (75.1%). Ibex Capra ibex, the only wild ungulate in our study area, contributed 18.2 and 16.9% of relative frequencies in the diets of the snow leopard and the wolf, respectively. In winter, the snow leopard heavily relied on domestic sheep (43.3%) for food, whereas the wolf preyed mainly on domestic goats (43.4%). Differently from other study areas, both snow leopards and wolves showed no apparent prey preference (Jacobs index: snow leopard min. ??0.098, max. 0.102; Tibetan wolf min. ??0.120, max. 0.03). In human depauperate areas, with livestock and only a few wild prey, should competitive interactions arise, two main scenarios could be expected, with either predator as a winner. In both cases, the best solution could primarily impinge on habitat restoration, so that a balance could be found between these predators, who have already coexisted for thousands of years.  相似文献   

8.
In the last decades, populations of large carnivores have been making a spectacular return, especially in the USA and Western Europe. These population recoveries result partially from protective legislation and reintroduction programs, but possibly also from land use changes and from large carnivores adapting to human environments. Although public support for large carnivore protection seems to be growing, some stakeholders still have a negative perception of large carnivores because of their alleged negative impacts on livestock and humans. Perceptions of large carnivores are partly determined by underlying visions of nature which differ between stakeholder groups. We therefore examined the relationship between different stakeholder groups’ perceptions of nature and the presence of the fox (Vulpes vulpes), and the possible establishment of the wolf (Canis lupus) and lynx (Lynx lynx) in a Dutch riverine landscape. Stakeholder groups comprised the general public, farmers, scientists and nature conservationists. Although perceptions of large carnivores differed significantly across the stakeholder groups, public support for large carnivores was generally higher than expected. Farmers show the most negative perception, especially regarding the wolf and lynx. This is related to their vision of nature, which is more strongly aligned with mastery over nature compared to other stakeholder groups. Scientists, prominent adherers of stewardship of nature, appear to have the most positive perception of large carnivores. Despite these differences in visions of nature, respondents generally adhere to the stewardship of nature relationship. This could be a good starting point to find common ground when disputes arise over large carnivores.  相似文献   

9.
Several mammal species have recolonized their historical ranges across Europe during the last decades. In November 2012, a wolf-looking canid was found dead in Thy National Park (56° 56′ N, 8° 25′ E) in Jutland, Denmark. DNA from this individual and nine German wolves were genotyped using a genome-wide panel of 22,163 canine single nucleotide polymorphism (SNP) markers and compared to existing profiles based on the same marker panel obtained from northeastern Polish (n?=?13) wolves, domestic dogs (n?=?13) and known wolf-dog hybrids (n?=?4). The Thy canid was confirmed to be a wolf from the German-western Polish population, approximately 800 km to the southeast. Access to the German reference database on DNA profiles based on 13 autosomal microsatellites of German wolves made it possible to pinpoint the exact pack origin of the Thy wolf in Saxony, Germany. This was the first documented observation of a wolf in Denmark in 200 years and another example of long-distance dispersal of a carnivore.  相似文献   

10.
Species morphological changes can be mutually influenced by environmental or biotic factors, such as competition. South American canids represent a quite recent radiation of taxa that evolved forms very disparate in phenotype, ecology and behaviour. Today, in the central part of South America there is one dominant large species (the maned wolf, Chrysocyon brachyurus) that directly influence sympatric smaller taxa via interspecific killing. Further south, three species of similar sized foxes (Lycalopex spp.) share the same habitats. Such unique combination of taxa and geographic distribution makes South American dogs an ideal group to test for the simultaneous impact of climate and competition on phenotypic variation. Using geometric morphometrics, we quantified skull size and shape of 431 specimens belonging to the eight extant South American canid species: Atelocynus microtis, Cerdocyon thous, Ch. brachyurus, Lycalopex culpaeus, L. griseus, L. gymnocercus, L. vetulus and Speothos venaticus. South American canids are significantly different in both skull size and shape. The hypercarnivorous bush dog is mostly distinct in shape from all the other taxa while a degree of overlap in shape—but not size—occurs between species of the genus Lycalopex. Both climate and competition impacts interspecific morphological variation. We identified climatic adaptations as the main driving force of diversification for the South American canids. Competition has a lower degree of impact on their skull morphology although it might have played a role in the past, when canid community was richer in morphotypes.  相似文献   

11.
Results of previous morphometric and genetic analyses of grey wolf (Canis lupus L.) population from Serbia indicated different patterns of population subdivision. In order to explore population structure, level of genetic variability, genetic drift, inbreeding and signals of bottleneck for grey wolves from Serbia, we applied highly polymorphic genetic markers (microsatellites). Obtained data are valuable in determination of conservation units and creation of appropriate management plans. We have amplified 18 highly polymorphic microsatellites, in a total sample of 75 grey wolves, from different localities across Serbia and multilocus genotypes were analyzed using appropriate software. Observed values of the basic genetic parameters (HO = 0.69; HE = 0.75) indicated moderate level of genetic variability, similar to genetic variability in other populations belonging to the Dinaric-Balkan population of grey wolf. In STRUCTURE analysis, although ΔK was estimated to be at first peak K = 2, and second peak K = 4, CLUMPAK analyses showed that there’s no structuring for any of assumed K, and therefore the population of grey wolf from Serbia may be considered as one continuous population and treated as one conservation unit in future management plans. Signals of bottleneck haven’t been observed (Wilcoxon test two phase mutation model p = 0.247; and stepwise mutation model p = 0.815).  相似文献   

12.
In this article, we present the results of the first systematic surveys of golden jackals in Bosnia and Herzegovina (B&H). The population status and distribution of the golden jackal (Canis aureus) in B&H was largely unknown, and the few existing literature records mention their presence at only five localities in the country. We interviewed managers of all the hunting grounds in B&H and reviewed available jackal hunting records from 2000 to 2016. In total, we collected 212 records of legally harvested jackals. We observed an increasing trend of harvested jackals in B&H (on average 35% annual increase) during this same period. Using the acoustic (playback) method, we confirmed the presence of 80 territorial jackal groups along six transects covering 3081 km2. We estimated density to be a minimum of 0.33 groups/10 km2 in northern B&H and 0.10 groups/10 km2 in central B&H. Jackal groups were located at significantly lower altitudes with respect to available area along the transects. We present a distribution map of confirmed jackal occurrences in B&H, which indicates that the core area of jackal distribution in the country is currently located along the Sava River and its tributaries in the northern part of B&H. Jackals are sporadically present in the rest of the country, where gray wolves (Canis lupus) probably limit their presence. In total, jackal presence has been detected in 19% (109 out of 586) of 10?×?10 km grid cells covering the country. The primary factor driving the expanding population of jackals in northern B&H appears to be immigration of jackals from Croatia and Serbia.  相似文献   

13.
Understanding predator-prey dynamics is an important component of management strategy development for wildlife populations that are directly affected by predation. Ungulates often serve as a significant source of prey for many large mammal predators, and patterns of predation are known to influence population dynamics. Although black bear and wolf diets have been investigated extensively, prey preference has been less commonly examined, especially in analyses that take into account age class (i.e., juvenile and adult) of the ungulate prey. We examined black bear (Ursus americanus), wolf (Canis lupus), and hybrids (Canis spp.) prey preference in Ontario based on the availability of three ungulate species—elk (Cervus elaphus), moose (Alces alces), and white-tailed deer (Odocoileus virginianus). We analyzed the presence of prey items in black bear and wolf scats collected over 3 years by examining prey hair cuticular scale patterns. We applied correction factors to frequencies of occurrence of prey items found in predator scat and related diet composition to the availability of ungulates, determined by fecal pellet transect surveys. In addition, non-ungulate diet items were identified to obtain full diet composition profiles. We found that black bear diet consisted of more than 87% vegetation, and they were opportunistic, not selecting for any particular ungulate species in either adult or juvenile age class. Wolf diet was comprised mainly of ungulates (~?73.2%), muskrat (Ondatra zibethica; ~?8.5%), and beaver (Castor canadensis; ~?14.6%), and although moose were at least 1.5 times more abundant then each of the other ungulate prey species in the study area, wolves preferred elk, using moose less than expected. Although we found black bear diet to be opportunistic during the summer, wolves in our study heavily utilized both juvenile and adult ungulates, however, among ungulate species, displayed preference for elk. The preference displayed by wolves provides insight that wildlife managers can use to guide further investigation and assist with the development of strategies to ensure continued elk reintroduction success, and moose and white-tailed deer population sustainability.  相似文献   

14.
The introduction of invasive alien predators often has catastrophic effects on populations of naïve native prey, but in situations where prey survive the initial impact a predator may act as a strong selective agent for prey that can discriminate and avoid it. Using two common species of Australian small mammals that have persisted in the presence of an alien predator, the European red fox Vulpes vulpes, for over a century, we hypothesised that populations of both would perform better where the activity of the predator was low than where it was high and that prey individuals would avoid signs of the predator’s presence. We found no difference in prey abundance in sites with high and low fox activity, but survival of one species—the bush rat Rattus fuscipes—was almost twofold higher where fox activity was low. Juvenile, but not adult rats, avoided fox odour on traps, as did individuals of the second prey species, the brown antechinus, Antechinus stuartii. Both species also showed reduced activity at foraging trays bearing fox odour in giving-up density (GUD) experiments, although GUDs and avoidance of fox odour declined over time. Young rats avoided fox odour more strongly where fox activity was high than where it was low, but neither adult R. fuscipes nor A. stuartii responded differently to different levels of fox activity. Conservation managers often attempt to eliminate alien predators or to protect predator-naïve prey in protected reserves. Our results suggest that, if predator pressure can be reduced, otherwise susceptible prey may survive the initial impact of an alien predator, and experience selection to discriminate cues to its presence and avoid it over the longer term. Although predator reduction is often feasible, identifying the level of reduction that will conserve prey and allow selection for avoidance remains an important challenge.  相似文献   

15.
Habitat loss and landscape degradation affect animal-mediated seed dispersal, often collapsing the regeneration of endangered plant species and habitats in anthropogenic landscapes. We first compared the role of red fox and other vertebrates as seed disperser for the keystone scrub Ziziphus lotus. Because it turned out that foxes are the major Z. lotus dispersers, we investigated how fox activity and dispersal service relate to habitat loss and landscape alteration in the threatened Ziziphus semiarid scrublands, a priority habitat for conservation in Europe. Considering its opportunistic behavior, we hypothesized that landscape features should affect moderately fox abundance, while influence in a large extent its dispersal service. Accordingly, we predicted that a substantial decline in Ziziphus fruit consumption rather than in disperser activity would be responsible for seed dispersal collapse under severe habitat loss. We evaluated fox activity and dispersal service in 17 populations of Z. lotus spread through the range of its habitat in Spain and found within landscapes with different land-use intensity. We certified the collapse of the dispersal service by fox under severe habitat loss and confirmed that fox activity was less affected by habitat loss or landscape alteration than consumption of Ziziphus fruits. Consequently, the decline of consumption of Ziziphus fruits under severe habitat loss triggers the collapse of its seed dispersal. Results suggest that without increase of the remnant areas other managements may not suffice to achieve seed dispersal and habitat restoring. Dispersal service and natural regeneration in many Ziziphus habitat remnants will possibly cease in the future if habitat loss continues.  相似文献   

16.
Human population growth around protected areas increases the contact between wild and domestic animals, promoting disease transmission between them. This study investigates the exposure of free-ranging wild carnivores and domestic dogs to canine distemper virus (CDV) and parvovirus in Emas National Park (ENP) in the Cerrado savanna of central Brazil. Serum samples were collected from 169 wild carnivores, including the maned wolf (Chrysocyon brachyurus), crab-eating fox (Cerdocyon thous), hoary fox (Pseudalopex vetulus), puma (Puma concolor), ocelot (Leopardus pardalis), pampas cat (Leopardus colocolo), jaguarundi (Herpailurus yagouaroundi), striped hog-nosed skunk (Conepatus semistriatus) and coati (Nasua nasua), and from 35 domestic dogs living on rural properties bordering ENP. Serological tests showed that 10.6% of wild carnivores (maned wolves, crab-eating foxes and ocelots) and 71.4% of domestic dogs were exposed to CDV, and 56.8% of wild carnivores, including all species sampled except coatis, and 57.1% of domestic dogs were exposed to parvovirus. This report is the first to indicate that the free-ranging pampas cat, jaguarundi and striped hog-nosed skunk are exposed to parvovirus. CDV and parvovirus deserve attention in ENP, and it is extremely important to monitor the health of carnivore populations and perform molecular diagnosis of the viruses to determine the possible involvement of the domestic dog in their transmission.  相似文献   

17.
Monitoring populations of elusive large carnivores like wolves (Canis lupus), which are often distributed at low density in widespread forested areas, is difficult or exceedingly expensive. Aiming to assess the power of two indirect monitoring methods, non-invasive genetic sampling and camera trapping, we designed a small-scale pilot study that was carried out from 2006 to 2008 in and around the Corno alle Scale Regional Park, Bologna, northern Italian Apennine. We collected 103 non-invasive samples (mainly scats) that were genotyped at 12 microsatellite loci and sexed using the ZFX gene. We identified 11 distinct wolf genotypes within the park and four wolf genotypes outside. Spatial locations and kinship analyses showed that the wolves belong to three different packs. The breeding pair of the ‘Park’ pack showed a complete turnover in the two sampling seasons. Two dogs, but no hybrids, were identified in the area. Up to five unbaited camera traps were activated (for 1,250 trapping-nights) close to recent wolf presence marks. We obtained 103 photos of wolves, documenting the reproduction events, the minimum number of adult and young wolves, and phenotype information each year. We obtained information on health conditions detecting probable sarcoptic mange in three individuals. Camera trapping also showed that the presence of wolves in a chase area during wild boar (Sus scrofa) hunting sessions was significantly higher in the nights just after a chase (P?χ 2 test; P?相似文献   

18.
Nymphs and larvae belonging to Ixodes spp. were collected from a red fox in Turkey. The ticks were identified morphologically and molecularly (16S rDNA PCR and phylogenetic analysis) as I. kaiseri. Sequence and phylogenetic analyses show that our I. kaiseri isolate is very similar to I. kaiseri isolates collected from Germany, Serbia, Romania, and Hungary. Therefore, the existence of I. kaiseri has been demonstrated for the first time in Turkey. More studies relating to the regional distribution and vectorial competence of I. kaiseri are needed.  相似文献   

19.
Negative impacts of non-native Harmonia axyridis (Pallas) on members of the native aphid enemy guild have been widely hypothesised but mainly only assessed with other coccinellid species, and mostly in small experimental arenas. Here we investigated the interactions between H. axyridis and Chrysoperla carnea Stephens larvae. In small-scale (Petri dish) arenas 2nd-instar C. carnea were at risk of predation from larval (2nd and 4th-instar) and adult (male and female) H. axyridis while 3rd-instar C. carnea were only at minimal risk from 4th-instar and adult female H. axyridis. Plant species, aphid species and aphid density did not affect intraguild predation of 2nd-instar C. carnea by 4th-instar and adult H. axyridis in mesocosm experiments. Chrysoperla carnea consumed similar numbers of Megoura viciae Buckton, Aphis fabae Scop. and Acyrthosiphon pisum Harris aphids while H. axyridis consumed fewer M. viciae than the other two species. The greatest suppression of A. pisum was achieved in treatments with both C. carnea and H. axyridis. Life stage and the sex of H. axyridis as well as the life stage of C. carnea are important variables affecting intraguild predation and these attributes should be considered when assessing the potential threat of other potentially invasive alien predators.  相似文献   

20.
The recent discovery of a lineage of gray wolf in North-East Africa suggests the presence of a cryptic canid on the continent, the African wolf Canis lupus lupaster. We analyzed the mtDNA diversity (cytochrome b and control region) of a series of African Canis including wolf-like animals from North and West Africa. Our objectives were to assess the actual range of C. l. lupaster, to further estimate the genetic characteristics and demographic history of its lineage, and to question its taxonomic delineation from the golden jackal C. aureus, with which it has been considered synonymous. We confirmed the existence of four distinct lineages within the gray wolf, including C. lupus/familiaris (Holarctic wolves and dogs), C. l. pallipes, C. l. chanco and C. l. lupaster. Taxonomic assignment procedures identified wolf-like individuals from Algeria, Mali and Senegal, as belonging to C. l. lupaster, expanding its known distribution c. 6,000 km to the west. We estimated that the African wolf lineage (i) had the highest level of genetic diversity within C. lupus, (ii) coalesced during the Late Pleistocene, contemporaneously with Holarctic wolves and dogs, and (iii) had an effective population size of c. 80,000 females. Our results suggest that the African wolf is a relatively ancient gray wolf lineage with a fairly large, past effective population size, as also suggested by the Pleistocene fossil record. Unique field observations in Senegal allowed us to provide a morphological and behavioral diagnosis of the African wolf that clearly distinguished it from the sympatric golden jackal. However, the detection of C. l. lupaster mtDNA haplotypes in C. aureus from Senegal brings the delineation between the African wolf and the golden jackal into question. In terms of conservation, it appears urgent to further characterize the status of the African wolf with regard to the African golden jackal.  相似文献   

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