Basic and Applied Ecology最新文献

Winter is a critical period for the survival of local bird species in temperate regions. Some wintering birds may rely on transient food, such as that provided at birdfeeders, but bird communities around birdfeeders may also attract predators. However, these effects of birdfeeders on interspecific interactions between birds and their predators remain largely unexplored and have so far not been tested experimentally. We hypothesized that birdfeeders indirectly attract predators in winter because of the attraction of small birds, and tested this hypothesis using experimental feeders at 52 different urban and rural sites across western Poland. We found that the number of small birds increased around birdfeeders, particularly those with provided food. We found that birdfeeders that attracted more small birds (regardless of whether they provided food) attracted also more predators, such as sparrowhawks Accipiter nisus and feral cats Felis domesticus. Moreover, birdfeeders in urban habitats attracted relatively fewer small birds but not fewer predators compared to those in rural areas. Altogether, birdfeeders with food provided attracted small prey birds but they attracted also more predators, whose presence may hinder small birds from fully utilizing available resources, potentially impacting their winter survival through direct (mortality) and indirect (increased monitoring and vigilance) effects.

Urban areas can be both detrimental for pollinators or function as suitable habitats, depending on the land-use type, the urban context and the pollinator group in focus. Urban green spaces, including gardens, parks or cemeteries can provide essential resources for a wide range of pollinator groups, like wild bees, hoverflies and beetles. Urban community gardens can be particularly structurally complex and harbour a diverse range of nesting and food resources for pollinators. However, we know little about how garden features may vary with the urban context of gardens and which specific garden features can increase the abundance of pollinators in general and of different pollinator groups.

Over two summer seasons, we recorded garden features and pollinators using flower observations in 33 urban community gardens in Munich and Berlin, Germany. We examined how garden features differ amongst urban community gardens from three urbanisation categories, and analysed the effects of garden features such as floral and nesting resources and landscape imperviousness (as indicator of urbanisation) on pollinator abundance, richness and diversity.

In more urbanised gardens, flower richness and bare substrate were less prevalent. Flower richness was positively correlated with overall pollinator abundance, richness and diversity as well as with the abundances of all pollinator taxa excluding beetles. Landscape imperviousness was negatively correlated with hoverfly and beetle abundances. Hoverflies also decreased with increasing bare substrate and wasp abundance decreased with increasing deadwood availability. Our findings highlight the important role of flower richness for insect conservation in urban management and show that pollinator taxa react differently to garden features and urbanisation. To support pollinating insects, gardeners can increase flower richness, especially in highly urbanised areas.

In the context of worldwide biodiversity and wild bee decline, it is increasingly important to better understand the effect of land-use changes on wild bee communities at a global scale. To do so, we studied the effect of city area and urban green spaces layout on wild bee species richness and community composition, as well as on wild bee species with an unfavorable UICN conservation status. This study was based on a large European dataset encompassing 20 cities from France, Belgium and Switzerland. We found a mean wild bee species richness in cities of 96 ± 48 (SD), showing that this species richness was highly variable among cities. The main factor positively influencing wild bee species richness in cities was the area of the city. Conversely, species richness was not significantly related to the total area of urban green spaces in a given city, measured as the spatial extent of urban parks, wastelands and other semi-natural habitats, excluding urban private gardens. Species with conservation status were quite scarce in urban environments, especially when compared to the European Red List of Bees, and we could not link their presence to either city or urban green space area. Dissimilarities in wild bee species community compositions were not associated with any of the studied characteristics of cities. We found that the dissimilarity of wild bee community composition among cities was mainly driven by the rarest species, as the most common ones were found in a majority of the cities sampled. Overall, these results emphasize that larger cities host more wild bee species, but are no refuge for the ones with concerning conservation status. Thus, stakeholders are encouraged to design their cities in favor of biodiversity to better support wild bee communities, and perhaps mitigate the established effect of the urban ecological filter.

To successfully conserve and restore agrobiodiversity, it is essential to understand the impact of multiple drivers and interlinkages across multiple taxa that occur above, across, and below the soil interface. Based on data from six agricultural landscapes in Central Germany, with 16 sampling plots per landscape, we used structural equation models to disentangle the impacts of climate, land-use, and soil factors on the diversity of multiple taxonomic groups. We expected belowground communities (soil bacteria and fungi) to be more driven by soil variables, mobile aboveground groups (wild bees, ground beetles) to be more driven by climate and land use, and vascular plants, that have an above- and belowground component, to respond to a combination of all factors.

According to our expectations, climate and land-use variables had an important role in shaping aboveground and plant communities. In contrast to our expectations, soil characteristics were of lesser importance for belowground organisms. Moreover, climatic factors had a strong impact on the soil microbiome, but this effect was indirect, modulated by soil pH. We also found indications for cascading effects of environmental factors via interlinkages within and among the above- and belowground communities. Our results highlight the importance of direct and indirect effects of multiple drivers on the diversity of multiple taxonomic groups and support recent calls for a multifunctional approach for sustainable landscape management and nature restoration, suggesting to focus on the promotion of semi-natural habitats but also considering the climatic context.

Allochthonous inputs often link nutrient cycles between different ecosystems as nitrogen (N) that originates in one ecosystem is transferred to another. Mobile animals such as birds and fish can translocate nutrients between locations. Consequently, animal-mediated nutrient subsidies can shape plant communities, especially in nutrient-poor ecosystems. Terrestrial cliffs are typically nutrient-poor, receiving N from atmospheric deposition and cliff-top runoff. Cliff nesting birds deposit N-rich excrement onto the cliff during nesting, yet this potential nutrient input has rarely been demonstrated. Here we document an allochthonous input of N from cliff-nesting birds to terrestrial cliff vegetation. We sampled mineral N and vegetation on eight cliff systems in western North Carolina (USA) with nests from peregrine falcon (F. peregrinus; two sites) and common raven (Corvus corax; five sites). Two sites had nests but species identity was not confirmed. Cliff faces below bird nests had higher levels of ammonium (NH₄⁺) than did faces without nests. Both ammonium and nitrate (NO₃⁻) explained variability in cliff vegetation community composition, but site-level characteristics explained more of the variation than did N inputs alone. Lichens, the dominant taxonomic group, contributed the most to this variation and had higher species richness and diversity below nests. Indicator species analysis identified two nitrophilic lichen species below nests: Flavoplaca citrina and Physcia caesia. A third nitrophilic lichen, Polycauliona candelaria (syn. Xanthoria candelaria) was also found under nests. Bird excrement is likely a significant subsidy to nutrient-poor terrestrial cliff ecosystems, thus linking cliffs to more productive ecosystems and highlighting the need to include birds in conservation and management of cliffs.

Intensively managed viticulture dominates vast landscapes in the Mediterranean, but considerable vineyard abandonment has been observed over the past two decades. The effect of vineyard abandonment on biodiversity is poorly understood, making it difficult to assess the restoration potential of this common land-use change.

We assessed biodiversity responses to vineyard abandonment in Vaucluse, Southern France, using birds as indicator group. We compared bird abundance and diversity in a sample of 64 vineyards, pairing 16 currently managed vineyards with 16 recently abandoned and 16 managed with 16 longer abandoned vineyards. We used mixed models and multivariate techniques to establish relationships between bird diversity and structural attributes of the habitats, and we derived management-specific population densities in a distance sampling approach.

Long-abandoned vineyards hosted three times more species and showed a 3.6 times higher total bird abundance than managed viticulture. More recently abandoned vineyards had intermediate species numbers and abundance. Species richness patterns were not modulated by landscape composition and configuration, but higher abundances were found in landscapes with intermediate size of land-cover patches (i.e. field size). In managed vineyards, bird abundances were extremely low, with the exception of Woodlark Lullula arborea, which reached its highest abundance in managed vineyards. The bird community on abandoned vineyards shifted towards forest and woodland shrub species, likely driven by secondary succession, namely shrub encroachment and tree establishment.

The strongly positive effects of land abandonment might be due to the fact that only single vineyards (not entire landscapes) were abandoned, thereby increasing habitat heterogeneity at the landscape scale. The future state of the old abandoned vineyards is difficult to predict. As of yet, the abandoned vineyards support a comparably diverse community of breeding birds that reach high abundances in comparison to managed vineyards, within an otherwise impoverished agricultural landscape.

In temperate regions, larger mammalian carrion naturally occurs in terrestrial landscapes as a pulsed resource towards the end of the winter through enhanced ungulate mortality due to starvation or exhaustion. The return of large carnivores in Central Europe provides carrion more equally throughout the year and the active enhancement of carrion for biodiversity by game managers has increased, raising the question of how different scavengers respond to the temporal variation in carrion supply. To address this question, we experimentally deployed 106 cervid carcasses throughout the year in a temperate forest of south-eastern Germany on two types of plots: permanent (i.e., site with multiple subsequent deployments) or random (i.e., site with unique deployment), and reported vertebrate scavenger visitations by camera trapping. Deployment on random or permanent sites did not affect carrion use by any single species. Generalized additive modelling revealed that vertebrate scavenging peaked in the winter season and summer independent of carrion supply. Still, different scavenger species showed different temporal patterns. While wild boar as ungulate omnivores did not display any seasonal patterns, avian scavengers showed significant variation in visitation rates. The mesopredator red fox consumed carrion significantly more often from late winter to summer, while pine marten was present at carrion only during winter. Finally, the specialist large carnivore Eurasian lynx, visited carrion sites most frequently in late winter and early spring. Our results suggest that global warming might impact some groups of vertebrate scavengers more strongly than others by reducing carrion availability in late winter, while returning carnivores could mitigate these impacts.

Interaction with urban nature provides many nature-derived benefits for people. However, human-nature interaction studies are conducted primarily during the vegetative season, but remain largely unexplored in winter. We therefore used non-participatory methods (i.e. systematically observing park users on-site) to characterize human-nature interactions in three urban parks in Stuttgart, Germany in the winter of 2020/2021 (N = 13,474 observations). Descriptive statistics were calculated and two multivariate logistic regression models built to serve as the basis for analyses. Results indicated that high-engagement human-nature interaction (i.e. nature photography, active observation, touching, or collecting natural elements) was generally low (2.4 % of observations) and that park visitors most frequently interacted with flora, then fauna, and finally abiotic natural elements. Certain visitation behaviors including technology use and visiting alone were associated with a lower odds of high-engagement nature interaction, whereas walking a dog was associated with a higher odds of high-engagement nature interaction. Additionally, odds of high-engagement nature interaction were higher at sites with a naturalized pond. While these findings are context-specific, they provide insight into the number of people that participate in high-engagement nature interaction, details into how they interact with urban nature in winter, and have potential implications for the design and management of urban greenspaces in future cities that best support both people and nature year round.

Future cities have the potential to be biodiverse areas in which humans and wildlife can coexist. However, the success of creating or maintaining wildlife-inclusive future cities can be challenged by management actions that are solely based on ecological research, while overlooking research on human perspectives. Despite the growth of literature on human-wildlife interactions, which complements the breadth of urban ecology research, the overlap between these two research areas is still uncommon. In this study, we reviewed the literature of wild mammals in urban areas to identify patterns and gaps in the literature. We found 848 published journal articles, of which 480 articles focused on wildlife ecology, 269 articles focused on human dimensions and 99 articles had interdisciplinary combinations of both. Ecology-centered publications tended to be about habitat, rather than behavior, diet, health, reproduction and inter-species-relations, and literature on human dimensions was more evenly divided into management, perception, conflict and coexistence. Most ecology studies reported on specific taxonomic families, mainly canids and murids, but in human-dimension studies, “wildlife” was considered more as a general community of species. The most studied interdisciplinary combination of research themes was wildlife habitat and human-wildlife conflicts (n = 22), while only nine studies incorporated perception with ecological research. Even though studies on human dimensions of wildlife in cities are increasing, interdisciplinary research is lacking, which limits the knowledge on how to manage and shape urban areas to achieve coexistence of humans and wild mammals. For future cities to successfully become biophilic and support human-wildlife coexistence, we outlined five key elements for a research agenda: 1) Investigate urban mammal research through an interdisciplinary lens; 2) Explore ecological dynamics beyond habitat selection; 3) Conduct research for coexistence; 4) Disentangle what is “urban wildlife”; 5) Study a diverse array of urban wild mammals.

Understanding the effects of microhabitat changes on arthropod predator communities and their prey in agroecosystems is essential for field management and biocontrol. Few studies have investigated the trait composition of web-building spider communities in rice ecosystems. Here, we examined how temporal changes during the rice field development affect the abundance and traits of orb-web spiders, and how these effects consequently influence captured prey number and prey composition in irrigated rice ecosystems in southern Thailand. We used structural equation models to evaluate direct and indirect, spider-mediated effects of rice field development on captured prey numbers in each different guild. We found that the number of horizontal web-building spiders decreased during the rice field development, whereas there was no significant change in number of vertical web-building spiders. The number of captured detritivorous insects was positively related to the numbers of horizontal and vertical web-building spiders, while phytophagous insects and others were positively related only to the numbers of vertical web-building spiders. Moreover, the prey number captured by vertical web-building spiders seems to be indirectly increased through the decreasing number of horizontal web-building spiders in the late rice season. A fourth-corner analysis showed that spider species identity, spider traits (web type, web height and web diameter), vegetation height, and water level generally influenced the prey captured by web-building spiders. Horizontal web-building spider species with lower web placement during the flooding phase captured high numbers of detritus-feeding insects, while vertical web-building spider species with higher web placement captured high numbers of rice pests, predators and others. Our results suggest that the field development acted as an environmental factor that determined the species identity and traits of web-building spider communities. The findings of this study can help to predict the ecosystem services provided by the web-building spider community in rice ecosystems.