Frugivore-mediated seed dispersal in fragmented landscapes: Compositional and functional turnover from forest to matrix.

Seed dispersal by frugivores is a fundamental function for plant community dynamics in fragmented landscapes, where forest remnants are typically embedded in a matrix of anthropogenic habitats. Frugivores can mediate both connectivity among forest remnants and plant colonization of the matrix. However, it remains poorly understood how frugivore communities change from forest to matrix due to the loss or replacement of species with traits that are less advantageous in open habitats and whether such changes ultimately influence the composition and traits of dispersed plants via species interactions. Here, we close this gap by using a unique dataset of seed-dispersal networks that were sampled in forest patches and adjacent matrix habitats of seven fragmented landscapes across Europe. We found a similar diversity of frugivores, plants, and interactions contributing to seed dispersal in forest and matrix, but a high turnover (replacement) in all these components. The turnover of dispersed seeds was smaller than that of frugivore communities because different frugivore species provided complementary seed dispersal in forest and matrix. Importantly, the turnover involved functional changes toward larger and more mobile frugivores in the matrix, which dispersed taller, larger-seeded plants with later fruiting periods. Our study provides a trait-based understanding of frugivore-mediated seed dispersal through fragmented landscapes, uncovering nonrandom shifts that can have cascading consequences for the composition of regenerating plant communities. Our findings also highlight the importance of forest remnants and frugivore faunas for ecosystem resilience, demonstrating a high potential for passive forest restoration of unmanaged lands in the matrix.

Songbird nests on the ground as islands of diversity of ptyctimous mites (Acari: Oribatida) in the primeval Bialowieza Forest (Poland).

Due to specific microclimatic conditions and accumulation of organic matter, bird nests are microhabitats that are often inhabited by various invertebrates, including mites (Acari). We tested whether nests of the ground-nesting passerine Phylloscopus sibilatrix (Bechstein) (Passeriformes: Phylloscopidae) [wood warbler] were associated with an increased local diversity of ptyctimous mites (Acari: Oribatida) on the forest floor in the Bialowieza National Park, East Poland. In 2019-2020, we analysed 150 warbler nests shortly after they had been vacated by the birds, and additionally we sampled mites in leaf litter at 1 and 6 m distances from 21 of the collected nests. We found on average more mite species in nests sampled in 2020 than in nests sampled in 2019. Although the species composition largely overlapped between bird nests and the litter, bird nests contained a greater average number of mite species than litter samples, including species found only - Microtritia minima (Berlese) and Phthiracarus crenophilus Willmann - or mostly - Euphthiracarus cribrarius (Berlese) and Phthiracarus globosus (C.L. Koch) - in bird nests. The results suggest that the presence of bird nests may increase the local diversity of the invertebrate species assemblage.

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

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.

Limited potential for bird migration to disperse plants to cooler latitudes.

Climate change is forcing the redistribution of life on Earth at an unprecedented velocity1,2. Migratory birds are thought to help plants to track climate change through long-distance seed dispersal3,4. However, seeds may be consistently dispersed towards cooler or warmer latitudes depending on whether the fruiting period of a plant species coincides with northward or southward migrations. Here we assess the potential of plant communities to keep pace with climate change through long-distance seed dispersal by migratory birds. To do so, we combine phenological and migration information with data on 949 seed-dispersal interactions between 46 bird and 81 plant species from 13 woodland communities across Europe. Most of the plant species (86%) in these communities are dispersed by birds migrating south, whereas only 35% are dispersed by birds migrating north; the latter subset is phylogenetically clustered in lineages that have fruiting periods that overlap with the spring migration. Moreover, the majority of this critical dispersal service northwards is provided by only a few Palaearctic migrant species. The potential of migratory birds to assist a small, non-random sample of plants to track climate change latitudinally is expected to strongly influence the formation of novel plant communities, and thus affect their ecosystem functions and community assembly at higher trophic levels.

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.

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

The setts of the European badger Meles meles can be cohabited during reproductive season by the red fox Vulpes vulpes and raccoon dog Nyctereutes procyonoides. There is no information on the possible impact of both species on the size of badgers' litter. The aim of the study was to show the influence of cohabitation of the same setts by badger, raccoon dog and fox on the litter size. The research was conducted in 2012-2014 and 2018 in the lowland forests of western Poland. We conducted the survey of setts by direct observations and analysis of photographic material from trap cameras during mid-April-July each year. We recorded 85 badger litters, 18 fox litters, and 15 raccoon dog litters. Average litter size was 1.71 (±0.90), 2.44 (±1.34) and 4.93 (±2.76) litter mates in badgers, foxes and raccoon dogs, respectively for all observed pairs. Badger litter size did not differ between setts used only by badgers including pairs with no cubs (1.66 ± 0.98) and cohabited with foxes (1.90 ± 0.32) or raccoon dogs (1.88 ± 0.81). However, foxes reared even more cubs in setts cohabited with badgers than when badger was absent (2.90 ± 1.37 vs. 1.88 ± 1.13 respectively). In the case of raccoon dogs, there were no differences in the mean number of their cubs in setts with badgers (5.25 ± 2.92) and without badgers (4.57 ± 2.76). The results indicate that the cohabitation of setts by badgers, foxes and raccoon dogs does not affect litter size negatively.