Reproduction success in European badgers, red foxes and raccoon dogs in relation to sett cohabitation

Study of Canine Distemper Virus Presence in Catalonia's Wild Carnivores through H Gene Amplification and Sequencing

Canine distemper virus (CDV) is recognised worldwide as an important pathogen in both domestic and wild carnivores. Few data are available on its impact and spread on the wildlife/wildlife-domestic animal-environment interface. This study, aimed at developing a conservation-oriented control strategy, analysed 89 sick or deceased animals from 2019 to 2023 at the Wildlife Rehabilitation Centre in Torreferrussa. RT-PCR and sequencing of the partial H gene were used to detect and analyse CDV in tissues. The total positive percentage was 20.22% (18/89), comprising 13 red foxes (44.8%), 4 European badgers (28.6%), and 1 American mink (4.5%), while 24 Eurasian otters tested negative. Phylogenetic analysis indicated that all of the CDV strains belong to the European lineage. Geographically distant individuals and different species shared the same viral strain, suggesting a strong capacity of CDV for interspecies and long-distance transmission. This calls for further research, particularly focusing on potential impacts of CDV on endangered carnivores.

Overwintering Culex torrentium in abandoned animal burrows as a reservoir for arboviruses in Central Europe

Culex pipiens s.s./Culex torrentium belong to the most widespread mosquito taxa in Europe and are the main vectors of Sindbis, West Nile and Usutu virus. The adult overwintering females can act as reservoir for these arthropod-borne viruses (arboviruses), thus contributing to their local persistence when transmission cycles are interrupted during the winter. However, the main overwintering sites of Cx. torrentium are unknown. In a study from 2017, 3455 Cx. pipiens s.s./Cx. torrentium specimens were collected from abandoned animal burrows in Poznan, Poland. These specimens were retrospectively identified to species-level with a PCR assay, which revealed Cx. torrentium as dominant species (> 60%). Motivated by these results, we conducted a field study from February to July 2022 to systematically analyse the overwintering site patterns of Cx. pipiens s.s./Cx. torrentium. Mosquitoes were sampled using pipe traps in abandoned animal burrows (n = 20) and with aspirators in nearby anthropogenic overwintering sites (n = 23). All Cx. pipiens s.s./Cx. torrentium were screened for Flaviviridae RNA. In total, 4710 mosquitoes of five different taxa were collected from anthropogenic sites. 3977 of them were identified as Cx. p. pipiens/Cx. torrentium (Cx. p. pipiens: 85%, Cx torrentium: 1%, pools with both species: 14%). In contrast, only Cx. p. pipiens/Cx. torrentium (1688 specimens) were collected from animal burrows dominated by Cx. torrentium (52%), followed by pools with both species (40%) and Cx. p pipiens (8%). A single pool of 10 Cx. torrentium specimens collected from an animal burrow was positive for Usutu virus. The detection of Usutu virus demonstrates that Cx. torrentium can act as winter reservoir for arboviruses. Abandoned animal burrows may by the primary overwintering site for the species and should be considered in future surveillance programmes, when sampling overwintering mosquitoes.

Den-Dwelling Carnivores in Central Poland: Long-Term Trends in Abundance and Productivity

The monitoring of medium-sized carnivores is essential because of their role in disease transmission and as predators. We focused on red foxes, badgers, raccoon dogs, and domestic dogs, and considered 9441 ha of field–forest mosaic in Central Poland. We compared current (2011–2018) abundance (i.e., number of natal dens recorded annually) and breeding parameters (assessed with the aid of camera traps) with published past data (1980s–1990s). The red fox population increased after rabies vaccinations were introduced and has increased further in the last few years. The population is now stable, which suggests that other factors, possibly mange, limit the population instead. Contrary to historical data, one-fourth of red fox females now breed outside of forests areas, indicating the high plasticity of the species. The number of natal dens of badgers and recruitment rates have also increased. The mean litter sizes of these two species are positively affected by small rodent availability. The raccoon dog, which is an alien and invasive species, used to be recorded sporadically but now breeds regularly (1.8 breeding cases yearly). Nowadays, free-ranging/feral domestic dogs are not controlled by culling, so they have started to breed in the wild (1.6 cases per year), which is a new occurrence.

Badger Meles meles as Ecosystem Engineer and Its Legal Status in Europe

Simple Summary

The European badger, listed in Bern Convention (protected fauna species), is also known as an important ecosystem engineer that creates new microhabitats among its setts suitable for the establishment of many plant and animal species. Badger setts are areas with topsoil disturbance and hence are places with higher species diversity than undisturbed surroundings. Much new data concerning the importance of badgers in ecosystem engineering indicates that the way badger populations are managed in Europe should be reconsidered. Thus, the aim of this study was to review the impact of badgers on shaping of species diversity in forest ecosystems with special attention to their legal status across Europe. The badger is hunted on 69.3% of the continent for 1.5–12 months per year. The real problem with management of this species concerns a quarter of its range in Europe, where the species can be hunted in winter and spring during mating season and during parturition. Reducing the hunting season to a maximum of three months in late autumn (September to November) seems to be a better approach. To prevent the negative effects of overhunting, special attention should be paid to population monitoring.

Abstract

The European badger plays an important role as a natural factor shaping species diversity in forests. Its extensive setts can be used by many other animals as shelters. Soil perturbations in their setts support plant communities that differ from the matrix landscape. The badger is also an effective seed disperser. We investigated its role as an ecosystem engineer in preserving species diversity and discussed its legal status across Europe. In most European countries (69.3% of the continent), the badger is hunted, sometimes year-round. The hunting season lasting through winter until early spring may have a negative effect on badger populations, especially when cubs are born in February. Although this species is Red Listed in 19 European countries (with categories ranging from LC to EN), the badger is strictly protected by law in 30.7% of its European range. A reduction in badger populations may limit its ecosystem services (seed dispersal, topsoil disturbances, microhabitat creation). Much new data on the importance of badgers in ecosystem engineering has allowed us to reconsider how we manage badger populations.

Long Arm of Motorway-The Impact of Fenced Road on the Mortality of European Badgers

We studied the impact of the new fenced and accident-safe motorway on the mortality of European badgers Meles meles on local roads in western Poland in 2010-2015. We monitored the badgers mortality on local roads of three categories: main roads, secondary roads and county roads. The study was conducted before and after the opening of the motorway in 2012. We hypothesized that the mortality of badgers is lower due to traffic concentration on motorway. Ninety two badgers were killed in collisions with vehicles on all monitored roads. Mean number of killed badgers was lowest in 2010 before the motorway opening and the highest in 2012. The mortality of badgers on regional roads was highest after the opening of the motorway due to the changes in traffic on the access roads. Within the road network, the mortality of badgers was 5.8 individuals/10 km of road per whole study period with the highest rate on main roads 8.5 individuals/10 km. The badgers mortality was highest on county roads but it was lower than expected in relation to the road network density. The highest vehicle collision risk for badgers of both sexes occurred in June. Distance to human settlements was the only environmental factor that was positively related to badger mortality on roads. We conclude that the new motorway did not reduce the mortality rate of badgers on the adjacent roads because the status of local roads has changed and now they mainly function as access roads to the motorway.

Organization of observations near underground shelters of burrowing carnivorans: a comparison of different methods

Observations near the burrows gives rich material on the biology, intraspecific and interspecific interactions, and individual behaviour of animals. In our work, we considered four methods of observation (visual observations, visual observations with photo-fixation, video surveillance, and camera trapping) of burrowing carnivorans near their underground shelters. The research was conducted in spring and summer in different years in the period from 2004 to 2021 in open and forest habitats near burrows of badgers (Meles meles Linnaeus, 1758) and foxes (Vulpes vulpes Linnaeus, 1758).Visual observations are always associated with the presence of humans near the underground shelter of burrowing carnivorans for a long period of time. The researcher can be present only at one burrow at a time. The advantages of this method are that it is simple, cheap and allows for observing not only the burrow, but also the surrounding area. Complementing the data of visual observations with photographs largely increases their scientific value and informativeness. The use of camera traps minimizes human impact on animal behaviour, covers more underground shelters (depending on the number of devices) and collects more concentrated material than other methods. Camera trapping and video surveillance is also more convenient for the researcher, especially during the round-the-clock collection of data. This method however requires significant material costs and time to review and sort materials before data analysis. Data collection is limited to the working area of devices that do not always have time to capture animals when they pass very quickly. It is important under different environmental conditions to choose the optimal method of observation in order to study the animals effectively. In open biotopes during the organization of observations, there are difficulties with the installation of photo- and video equipment and its camouflage. In our opinion, the method of visual observations with photo-fixation remains relevant in conducting research near underground shelters of burrowing carnivorans under such conditions. The method of camera trapping is optimal for forest biotopes.

Underground diversity: Uropodina mites (Acari: Mesostigmata) from European badger (Meles meles) nests

Badgers can gather huge quantities of organic material to build their nests for winter time and to rear their cubs. Moreover, badger burrows (setts) are characterized by specific microclimate with quite stable temperature and humidity. Their fauna is poorly studied, especially in respect of saprobiontic Uropodina mites. In 2018-2019, we monitored 94 badger setts to search for nest material that had been thrown away during cleaning of the chambers after mating and winter sleep. In the collected material from 32 badger nests, we found 413 Uropodina mites of 16 species, in various stages of development (adults, protonymphs, and deutonymphs). The community was dominated by three mite species: Trematura patavina (22.5%, n = 93), Oodinychus ovalis (17.2%, n = 71), and Olodiscus minima (15.5%, n = 64). Other nidicolous-i.e., nest-dwelling-species included: Nenteria oudemansi (14.8%, n = 61), Phaulodiaspis borealis (7.0%, n = 29), Phaulodiaspis rackei (4.6%, n = 19), Uroseius hunzikeri (1.7%, n = 7), Uropoda orbicularis (1.5%, n = 6), and Apionoseius infirmus (1.0%, n = 4). The most frequent species were: Oodinychus ovalis (62.5%, 20 nests), N. oudemansi (46.9%, 15 nests), and Olodiscus minima (40.6%, 13 nests). Detrended correspondence analysis indicated that the Uropodina community from badger nests differed from that of mole nests, studied earlier. In setts, the Uropodina community included T. patavina and N. oudemansi, which were for the first time recorded from underground badger nests. This is the first record of N. oudemansi from Poland.