European Journal of Wildlife Research最新文献

Abstract

Species introductions outside their native ranges, often driven by trade and other anthropogenic activities, present significant ecological challenges. Reptiles, frequently traded as pets for their attractiveness, are particularly susceptible to such introductions, leading to shifts in distribution patterns and potential ecological impacts. The common chameleon (Chamaeleo chamaeleon), which has been historically introduced in several European countries, is such an example, yet no overall assessments are available to date for this species. In this study, we used ecological niche models to assess habitat suitability for the common chameleon in the Mediterranean basin for current and future scenarios. Concurrently, circuit theory techniques were employed to evaluate habitat connectivity in two historically introduced areas. We identified areas of high habitat suitability and dispersal corridors in introduced regions. Our results reveal a latitudinal gradient in habitat suitability changes, with the species facing both expansion and decline in different parts of its range, depending on the ecozone considered. Severe declines are noted in southeastern Spain, Tunisia, and Israel, while habitat suitability increases westwards in Portugal, Morocco, and Southern Italy. These insights contribute to a better understanding of the common chameleon’s ecological dynamics, providing a foundation for targeted management and conservation efforts. Our study highlights the importance of integrating ecological niche modelling and circuit theory techniques to predict habitat suitability and identify critical dispersal corridors for effective conservation strategies. Considering the ongoing challenges posed by human-mediated dispersals for the common chameleon, our research establishes a foundation for future studies to enhance our understanding of this elusive species.

Nest predation is one of the main factors shaping waterbird abundances, but the impact of different predator species varies considerably between habitats and sites. To identify nest predators and evaluate their spatio-temporal impact on waterbird broods, we carried out a study with artificial nests and camera traps placed in the reedbeds of two eutrophic lakes in northeastern Poland. We also analyzed the importance of two factors for nest survival—water depth at nest site and egg concealment. Artificial nest survival was very low, with only about 8% of the nests surviving more than 10 days. Among the four most frequently recorded nest predators that comprised 95% of all predators filmed, the raccoon dog Nyctereutes procyonoides dominated (51.7% of records), followed by the marsh harrier Circus aeruginosus (24.5%), hooded crow Corvus cornix (12.2%), and American mink Neogale vison (11.6%). The predation rate of the raccoon dog significantly increased over time, being highest in July, and was opposite to that of the marsh harrier, whose nest predation was highest in April and declined over the next months, while the predation rates of the hooded crow and mink were stable. The concealing of eggs did not significantly decrease the probability of depredating nests. Water depth also did not significantly affect nest survival, and only the raccoon dog’s predation rate was negatively related to water depth. Birds depredated nests during the day and mammals both during the day and night; however, activity patterns of four main predators highly overlapped.

Abstract

In poultry industry, mycoplasmas cause large economic losses. The pathogenic significance of mycoplasmas varies widely between species. In birds where vocalization is crucial for reproductive success, mycoplasmas seem to be absent. Birds with high mycoplasma prevalence like birds of prey and storks do not rely on their vocalization for reproduction. Corvids with an intermediate prevalence use other strategies besides vocalization for mating. It is hypothesized that mycoplasma prevalence and vocalization used for reproduction is evolutionary related. Barn swallows have two traits relevant for mating: tail feather length and vocalization. An intermediate prevalence is expected. Little is known about mycoplasmas in barn swallows and their role as vector or reservoir for poultry pathogenic mycoplasmas. This study investigates the prevalence of mycoplasmas in barn swallows and their relevance for mycoplasma transmission to poultry. Choanal swabs from 188 healthy barn swallow nestlings of 59 different nests from ten different colonies on farms were examined for mycoplasmas by cultivation and genus-specific PCR including molecular biological differentiation of the species. In total, in 31 of 188 barn swallows (16.49%) and in 14 of the 59 nests (23.73%), mycoplasmas were detected. The occurrence of mycoplasmas per colony ranged from 0 to 50% independent of poultry being kept on the farm. In all positive samples, Mycoplasma sturni was identified. Mycoplasma sturni seems not to be an obligatory pathogen for barn swallows and occurs with an expected intermediate prevalence in them, so the results support the described hypothesis and underline a minor role of barn swallows for mycoplasma infection in poultry.

Acquiring up-to-date information on the distribution of a species is an issue of paramount importance to set up proper conservation strategies and to assess its conservation status over time. The European wildcat has recently expanded its distribution in different parts of its range in Italy, including the Northern Apennines area. The current study represents the first wildcat systematic monitoring in the central part of Northern Apennines. Non-invasive genetic sampling—based both on valerian and catnip lures—was applied, integrated with camera trapping within two Regional Parks. This approach is needed in order to obtain hair samples to be genetically analyzed, since cross-breeding with domestic cats can make wildcat identification based only on coat characteristics misleading. Videos obtained from camera traps allowed the identification of several individuals (image capture rate of 1.04/100 trap-nights), including at least one female. Hair samples were only collected in April–May using catnip as an attractant, whereas the valerian-based solution used did not yield the expected results (i.e., attracting wildcats and stimulating their rubbing behavior to allow hair collection). These results allowed for the first time the genetic confirmation of a pure wildcat in the study area. Domestic cat presence (image capture rate of 1.4/100 trap-nights) was also assessed in the same locations, posing a possible threat for wildcat conservation at the expanding margin of its distribution. Our findings confirm the effectiveness of the integration of multiple monitoring techniques for wildcat detection and highlight the need for a continued monitoring of the species, especially in newly colonized areas.

The Cantabrian brown bear (Ursus arctos) population is threatened although in a constant process of recovery during the last 20 years. Since data on the parasitological status of this bear is still limited, the objective of the present study was to assess the diversity and prevalence of parasites in this population. Thus, 111 bear faecal samples were collected in north-western Spain and analysed for estimating the occurrence of gastrointestinal and bronchopulmonary parasites. Samples were processed by flotation in saline and sucrose solution, sedimentation and Baermann-Wetzel techniques. In addition, a commercial immunofluorescent assay was performed for detecting Giardia duodenalis and Cryptosporidium spp. Dicrocoelium dendriticum was the most prevalent parasite (58.6%), followed by Baylisascaris transfuga (43.2%) and nematodes of the Suborder Strongylida (18.9%) and Spirurida (2.7%). Mixed infections were detected in the 41.4% of the samples. The presence of D. dendriticum was significantly highest in bears from the autonomous region of Castile and León as well as in those in which grass or nuts/acorns were the predominant food item. Moreover, the risk of being positive to B. transfuga was significantly higher during autumn–winter, and in those, faecal samples were mainly composed of fleshy fruit. Some of the parasites detected could infect other wildlife and even humans, and therefore, the risk of pathogen transmission deserves further investigation. Since the impact of endoparasites in the health status of bears is poorly understood, the establishment of a disease surveillance protocol is strongly recommended in order to assess the potential risk of these infections for bears.

Knowledge of the large carnivore guild is important in view of a possible lion reintroduction into the Comoé National Park (CNP), northern Côte d’Ivoire. We used camera trapping to assess activity patterns, habitat selection, and ecological factors influencing the occupancy of the spotted hyena Crocuta crocuta. Our results showed that the presence of leopard Panthera pardus, the only current other large carnivore and thus potential competitor, did not influence hyena occupancy. Hyena occupancy was only significantly related to Euclidian distance to nearest water point. Manly’s alpha habitat selection index values show a preference of spotted hyena for shrub savannah (α_Sa = 0.71), and Pianka’s overlap index showed low spatial competition with leopard (OIJ_(PNC) = 0.12). Our findings showed that spotted hyena were mostly nocturnal, and generally active at the same time slots with leopard, leading to a high index of temporal overlap (OIJ_(time) = 0.78). The kernel density estimation confirmed that spotted hyenas and leopard shared almost half of their activity patterns (Δ1 = 0.49 and 95% CI = 0.26–0.71). Prey diversity is high in CNP but anthropogenic threats appear to suppress population growth of prey and predators. Conservation efforts should continue to reduce pressures before contemplating a potential lion Panthera leo reintroduction.

Human disturbance has been shown to provoke physiological and behavioral responses in birds, so nature-based tourism might reduce bird abundance and diversity. The negative consequences of human disturbance might be expected to be maximized during eventual massive events in highly protected areas such as national parks. In this study, the consequences for soundscapes of human presence and disturbance of thousands of visitors during an ornithological fair (massive event) on the bird community of the Monfragüe National Park (Spain) were analyzed. We found that the number and diversity of bird vocalizations did not decrease during the massive event. In contrast, the presence of people in the Monfragüe National Park was associated with an increase in the number and diversity of vocalizations. The effect of human presence on the number of calls and songs differed: the number of calls mainly increased during the massive event when people were present, while the number of songs increased when people were present, particularly during the measurement campaign without the massive event. The human shield hypothesis, along with other behavioral and environmental factors, might potentially explain the results obtained.

Abstract

In recent decades, the golden jackal Canis aureus has experienced a population increase in many European countries, including Croatia. As a result, human-jackal conflicts (e.g., damage to livestock and wildlife, general nuisance in (sub)urban areas) have increased dramatically, and there is an urgent need to develop and use a range of mitigation tools that also aim to control population growth. Hunting is one of the well-known tools for population control; therefore, the aim of this study was to determine the effects of habitat type and weather conditions on jackal hunting success. From 2019 to 2023, a total of 217 jackals were culled during 106 hunting events in an approximately 10,500 ha lowland habitat along the Sava River in central Croatia. All jackals (56% males and 44% females) were culled using small calibre rifle (222 Remington) with night vision scope. Based on age structure, 16% juveniles and 84% adults were shot, and the average catch per unit effort (CPUE) was 2.0 animals/day. The best hunting success was obtained by attracting jackals with a calling method, i.e., by playing the sound of a wounded hare. Regarding the type of habitat, 56% of the culls were in cultivated, non-forested areas. It was confirmed that weather conditions, i.e., daily temperature and precipitation, influence hunting success, especially for males. Hunting success of adult males was lower on days with higher temperatures and on days with more precipitation. We can state that individual hunting with using calling method is an effective tool for successful golden jackals harvesting; moreover, jackal hunting can minimize the conflict with gamekeepers and farmers and would help to improve public perception of jackals.

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.