Antibodies against the Mycobacterium tuberculosis complex and Brucella spp. in captive and free-living European bison (Bison bonasus) in Poland

BACKGROUND

The European bison (Bison bonasus), a symbol of Polish nature, is a protected species that requires active health monitoring. However, conservation efforts are made difficult by the zoonotic diseases such as brucellosis and tuberculosis.

OBJECTIVE

The aim of this study was to screen the Polish European bison population for exposure to the Mycobacterium tuberculosis complex (MTC) and Brucella spp.

METHODS

A total of 323 free-living and captive European bison from 13 localities were tested serologically for antibodies against the M. bovis P22 multi-protein complex (in-house ELISA) and against Brucella spp. (commercial ELISA).

RESULTS

Antibodies against the MTC (P22) were detected in 7% (22/323) of the tested European bison. Anti-MTC antibody positivity was not significantly different by sex, age, and captive/free range status. Anti-MTC antibodies were found in six of 13 populations sampled, always in populations with larger sample sizes including the four free-living ones. Antibodies against Brucella spp. were detected in 36% (116/323) of the tested bison. While Brucella spp. antibody prevalence was not different by sex, it was significantly different by age (lower in adults) and captive/free-living status. Brucella spp. seroprevalence decreased with sample size and seropositive bison were found in 12 of 13 sampling populations.

CONCLUSIONS

Our findings identify potential emerging threats to the European bison population and confirm the first serological response to P22 in European bison. As Poland is currently officially free of brucellosis and bovine tuberculosis, our results require careful interpretation. Further studies are needed to establish the presence of cross-reactions with atypical mycobacteria in the case of MTC and other bacteria (e.g. Yersinia enterocolitica O:9) in the case of Brucella spp.

Selection of Flagship Species and Their Use as Umbrellas in Bird Conservation: A Case Study in Lishui, Zhejiang Province, China

The concept of flagship species is widely used in conservation biology. Flagship birds play a key role in raising conservation funds, increasing awareness of biodiversity conservation, and maintaining ecosystem services. This study selected flagship bird species in Lishui, Zhejiang Province, China, and assessed their conservation effectiveness and ability to serve as umbrella species. A regional bird survey program from 2019-2022 recorded 361 bird species in Lishui. This study constructed a framework of flagship species selection based on social, ecological, economic, and cultural criteria. The analytic hierarchy process-entropy weight method (AHP-EM) was used to rank the score of 361 bird species, and the MaxEnt model was used to analyze the suitable distribution areas of these species. Finally, 10 species, which covered the distribution sites of all 361 bird species, were selected as the flagship species of Lishui. The distribution areas covered all the nature reserves and the priority areas of biodiversity of Lishui, in which these 10 species can also serve as umbrella species to protect local biodiversity. The methodology and ideas in this study could provide insights into the application of conservation concepts at the local level, as well as suggest possible recommendations for local governments to select flagship species for conservation.

Artificial Waterholes for European Bison as Biodiversity Hotspots in Forest Ecosystems: Ecological Effects of Species Reintroduction Activities

Despite the growing population of European bison (Bison bonasus), it is necessary to plan the reintroduction of these animals to new areas. Reintroduction of European bison often requires the improvement of natural conditions. Such preparatory activities allow European bison to more easily adapt to new places, but also impact the functioning of animals from other taxa. The aim of the presented study was to examine the impact of waterholes for European bison on the development of local populations of amphibians and dragonflies (Odonata), as well as the creation of new feeding grounds for bats. We examined 15 reservoirs in the Augustów Forest District located in northeastern Poland, of which five were waterholes for European bison built in 2013–2014, four were semi-natural reservoirs transformed into waterholes for European bison in 2018, and six were natural reservoirs. Dragonflies were studied in 2021–2022; amphibians in 2018 and 2020; and bats in 2018, 2019, and 2020. In total, 24 species of dragonflies (Odonata), 10 species of amphibians, and 13 species of bats were found. The results of the inventory of three taxonomic groups using different comparative variants indicate a significant impact of the construction of waterholes for European bison on the biodiversity of the forest ecosystem. We concluded that the waterholes for European bison present better resistance to drying out than natural reservoirs. In addition, waterholes warm up more quickly, supporting better conditions for amphibians. The surface of the reservoirs and their exposed surroundings are favorable for insects (including dragonflies), and these are a source of food for bats, becoming attractive feeding grounds for them.

The Effect of European Bison (Bison bonasus) Translocations on the Persistence and Genetic Diversity of Ex Situ Herds—A Modelling Study

The conservation of the genetic diversity of the European bison population is carried out mainly in ex situ herds, constituting a functional metapopulation. The breeders have to balance between the available capacity of the reserves and the need to enrich the free and semi-free herds with appropriate individuals. If there are limitations (e.g., financial) in the transfer of individuals, breeders report a problem of surplus individuals. The aim of this study was to estimate the migration parameters in the wisent metapopulation ex situ to maintain genetic diversity in hypothetical herds. The analysis was a two-step process. The first part of this study was carried out between the years 1998 and 2017, based on information from the European Bison Pedigree Book about eight selected herds. The average annual share of exported and imported individuals in the chosen metapopulation were calculated (8.81% (SD: 11.51) and 0.75% (SD: 2.15), respectively). The proportion of males to females among the exported animals was close to 1:1. The sex ratio of imported animals was close to 2:1 (M:F). The majority of transports were exports of animals (92.1%). The share of individuals exported from different age–sex groups was calculated. On this basis, in the second part of the study, the proportion of exported surplus individuals in the smallest hypothetical herd was established as 5.89% of the adult females, or 8.98% of adult males, or 32.70% of females aged 1–3 years. In order to maintain the genetic sustainability of hypothetical herds it is crucial to import individuals (M/F: 1/1; interval: 10 years). The results of this study will provide necessary information to determine the tools of wisent population management in the enclosure.

Social feasibility assessments in conservation translocations

Improving the effectiveness of conservation translocations could contribute to reversing global biodiversity loss. Although evaluations of ecological factors affecting translocation outcomes are commonplace, consideration of human social factors remains rare, hindering improvements to this conservation practice. We analysed 550 translocation case studies to explore the inclusion of social factors in project feasibility assessments. Reviewed projects often failed to assess social feasibility, and assessments, where attempted, tended to be narrow in scope. Consequently, challenges such as proactively addressing conflict often remained unaddressed. Insufficient knowledge sharing and prioritisation of ecological feasibility, to the detriment of social feasibility, remain barriers to effective planning. Successful outcomes of translocations are linked to early assessment of social feasibility and to the establishment of long-term commitments between people, places, and partners.

Enhancing monitoring of rewilding progress through wildlife tracking and remote sensing

Defaunation is a global threat to biodiversity that can be counteracted through trophic rewilding, a restoration strategy that promotes self-regulating ecosystems through active reintroductions or passive management. In order to estimate success in restoration initiatives, progress of the rewilding projects is measured and monitored. However, a spatially explicit understanding of rewilding and rewilding potential in a rewilding site has been absent so far. We present a novel approach for monitoring rewilding progress that focuses on a spatially explicit estimate of progress and ecological integrity within rewilding initiatives. This framework uses habitat classification of the site and tracking data of the reintroduced animals, to model their habitat selection. Through this we measure and map realized and potential rewilding. We operationalize the framework in an ongoing rewilding project in the Iberá Wetlands, Corrientes, Argentina. The majority of areas (76%) predicted to be occupied by reintroduced fauna were only predicted to be selected by one species. Of the four species in the rewilding project, only the giant anteater (Myrmecophaga tridactyla) filled the majority of its potential distribution, whereas pampas deer (Ozotoceros bezoarticus), collared peccary (Pecari tajacu) and lowland tapir (Tapirus terrestris) filled less than 23% of theirs. After rewilding we found a 10% increase in the proportion of the study area with high ecological integrity. Through this case study, we showed that this framework can be used to assess the spatial progress of a rewilding site. By incorporating wildlife tracking and satellite-based remote sensing, we are integrating a spatial component to monitoring of rewilding projects that should lead to more detailed understanding of the progress of rewilding. Applying this framework would facilitate decision-making for practitioners and inform species management plans.

Human-Wildlife Conflict: The Human Dimension of European Bison Conservation in the Bieszczady Mountains (Poland)

An important limitation for the population growth of European bison in the Bieszczady Mountains may be the level of social acceptance. The study aimed to compare attitudes to European bison of local village inhabitants in Bieszczady and city dwellers in Rzeszów. We also investigated whether damage caused by European bison or other wild species changes peoples' perceptions of this animal. Our study showed that not only does the growing European bison population cause an increase in negative attitudes among local village communities, but this species also causes more conflict than any other herbivore in the Bieszczady Mountains. Village residents believed that the main threats that arise from European bison were the damage they cause and forest use limitations. The current compensation system for the damage caused by this species does not solve the problem because over 60% of damage is not effectively reported to the state administration. The city dwellers of Rzeszów displayed a different attitude towards the European bison. We concluded that while educational workshops for local villagers may alleviate conflict in the short-term, ultimately it is only by restricting the growth of the European bison population that a long-term effect will be achieved.

Genetic signature of disease epizootic and reintroduction history in an endangered carnivore

Emerging infectious diseases have recently increased in wildlife and can result in population declines and the loss of genetic diversity in susceptible populations. As populations of impacted species decline, genetic diversity can be lost, with ramifications including reduced effective population size and increased population structuring. For species of conservation concern, which may already have low genetic diversity, the loss of genetic diversity can be especially important. To investigate the impacts of a novel pathogen on genetic diversity in a genetically depauperate endangered species, we assessed the ramifications of a sylvatic plague-induced bottleneck in black-footed ferrets (Mustela nigripes). Following a plague epizootic, we genotyped 184 ferrets from Conata Basin and Badlands National Park, South Dakota, at seven microsatellite loci. We compared our results to pre-plague studies in the same population. We observed population substructuring into three genetic clusters. These clusters reflect founder effects from ferret reintroduction events followed by genetic drift. Compared to the pre-plague population, we observed losses of allelic diversity in all clusters, as well as significantly reduced heterozygosity in one cluster. These results indicate that disease epizootics may reduce population size and also genetic diversity. Our results suggest the importance of early and sustained management in mitigating disease epizootics in naïve populations for the maintenance of genetic diversity.