Bird biodiversity in vegetation along unpaved rural roads in Central European farmland

Tropical forests hold two-thirds of the world's biodiversity but have declined due to forest degradation and deforestation, mainly driven by agricultural expansion. Although agricultural lands, such as plantations and orchards, are matrices (i.e., unsuitable habitats) for many forest species in general, their impact on biodiversity could largely differ depending on the type of agricultural land and management practices. Therefore, understanding the impact of different agricultural land types on biodiversity is important for planning matrix management in tropical agricultural landscapes. This study assessed the potential of monoculture oil palm and rubber tree plantations, as well as polyculture orchards, to support understory bird diversity compared to forest reserves in Peninsular Malaysia using mist-netting conducted between 2017-2023. Orchards recorded the highest bird abundance and richness among agricultural lands, but all agricultural lands had less than half the understory bird species found in forest reserves. Bird species composition also differed significantly among all habitats; forest specialists dominated (81.8%) in forest reserves, whereas nonforest specialists were dominant in orchards (76.3%), oil palm (100%), and rubber tree plantations (100%). Among habitat variables, understory vegetation covers positively affected bird species richness. Our results suggest that, despite having much lower diversity than forest reserves, polyculture orchards had some forest-specialist species that possibly spilled over from forest reserves, and thus, are better habitats for understory bird communities than monoculture plantations. Maintaining crop diversity and understory vegetation complexity can improve matrix quality and mitigate the impact on biodiversity in landscapes dominated by monoculture plantations.

European forests play an important role for climate change mitigation and biodiversity conservation. As they have been shaped by silviculture for centuries, it is important to understand how management practices affect forest structure and in turn influence the role of forests in achieving both goals. We analyzed data on a wide range of temperate European forests encompassing the most widespread management regimes to understand the interplay of forest structure, aboveground carbon stocks, and the richness of several taxonomic groups. Using structural equation modeling, we identified the forest structural characteristics that are positively correlated with both carbon stocks and species richness. We found that stand age and tree species richness are related to other forest structural characteristics, which had positive links to carbon stocks in deadwood. Increasing stand age was associated with an increase in deadwood carbon stocks. There were no direct negative relationships between stand age or tree species richness and the richness of different taxonomic groups. An increasing richness of deadwood types had positive links with the species richness of birds, saproxylic beetles, and saproxylic fungi, as with deadwood carbon stocks. However, increases in the species richness of birds and understory vascular plants were negatively related to increasing carbon stocks in living wood, while beetle species richness was positively related to this carbon stock. Birds' species richness was directly and positively associated with increasing mean tree diameter. Conversely, a higher richness of tree species was indirectly linked to lower carbon stocks in living wood. Additionally, an increase in mean tree diameter was indirectly correlated with a decrease in bird and vascular plant species richness. Our findings highlight potential trade‐offs between carbon stocks in living wood and the species richness of several taxonomic groups in European forests, while the species richness of some taxonomic groups was positively correlated to deadwood carbon stocks. Policies focused on increasing living biomass may not target both the climate and biodiversity crises. Instead, the diversity of deadwood emerges as a key factor in explaining the relationship between carbon storage and biodiversity, and should hence play a prominent role in forest management strategies and related policies.

The development of wind power leads to a decline in bird species richness

Global fire regimes are changing, raising concerns about the ability of fire-prone ecosystems to maintain biodiversity. We tested whether the pyrodiversity-biodiversity hypothesis (i.e., variation in postfire characteristics promotes biodiversity) or alternative hypotheses better explain patterns of biodiversity in a true island system. Using fixed-area sampling plots in a chronosequence of 42 boreal lake islands spanning gradients in island area (1-350.4 ha), isolation (0.1-7.9 km from mainland), and fire history (1-231+ year since fire), we tested whether alpha and beta diversity of beetles, plants, and birds increased with spatial (within-island variation in burn severity) and temporal (variation in time since fire among islands) pyrodiversity, respectively. Species richness of plants and birds increased with spatial pyrodiversity indicating that habitat heterogeneity from localized variation in burn severity supported more species in some groups. Beta diversity of all taxa increased with temporal pyrodiversity, highlighting the importance of conserving age-class variation within the boreal patch mosaic. In contrast, the habitat amount hypothesis and island biogeography theory were weak predictors of species richness across all taxa, and island area and isolation did not consistently affect beta diversity among the islands. Our findings emphasize the importance of maintaining pyrodiversity in boreal landscapes to combat biodiversity loss in the age of "megafires" and suggest leveraging the fire refugia effects of large lakes within the region to conserve vital components of temporal pyrodiversity such as old-growth forests.

Bird species richness peaks at intermediate levels of farmland in wooded savannas and dry forests, but not in rainforests

Assessing how bird richness across ecological guilds of mountain-breeding birds responds to changes in forest attributes may inform the development of sustainable management strategies. In this study, we surveyed forest structure and bird communities across 148 sampling units in France and Italy to identify threshold values for stand variables that influence bird species richness. The sampling covered an altitudinal range from 805 to 1555 m a.s.l. and was mainly dominated by mountain beech and Alpine coniferous forests. We modelled species richness of overall bird communities and individual ecological guilds in response to structural and compositional attributes and topographic variables using generalized modelling. Bird species richness was negatively associated with stand-level total tree density. However, higher silver fir density was associated with greater species richness across most bird guilds, which preferred mixed woods and heterogeneous stand structure. An increase in deadwood volume had a significant positive effect on all guilds, confirming the importance of old-growth forest features for forest birds. Threshold values indicating a shift in species richness of bird guilds were identified only for some stand structural attributes (i.e., total basal area and deadwood volume). Our results suggest that the conservation of biodiversity in forest bird communities may benefit from management strategies that maintain mixed, relatively open canopies and promote deadwood retention to ensure the availability of associated habitats. Our approach lays the groundwork for further research, applying this methodology to additional variables and biodiversity metrics.

Reconciling carbon (C) sequestration with biodiversity conservation remains a key challenge for sustainable forest management, as C–biodiversity relationships vary across taxa and contexts. We evaluated how botanical composition, forest structure, C pools, and land use predict species richness of insects, birds, and bats across mature temperate forests in southern Québec, Canada. Generalized linear models were fitted for insects and birds, while bat data were analyzed descriptively due to low and uneven richness. Botanical composition and forest structure were the most consistent predictors across groups. Insects responded strongly to vegetation structure and C allocation, with richness decreasing with shrub density and mineral soil C but increasing with the soil:above-ground C ratio and distance from infrastructure. Bird richness increased with herbaceous cover and wetland area, emphasizing the value of open and moist habitats. Across taxa, C pools acted as secondary but complementary predictors. Based on observational analyses, our results show that C–biodiversity relationships are compartment-specific and taxon-sensitive, and suggest that maintaining structural complexity, diverse vegetation strata, wetland habitats, and soil C pools may help align biodiversity conservation with C sequestration objectives in temperate forests.

Cameron C. 2026. Waterbird species–area relationships at Florida lakes: evaluating a lake area management threshold using citizen science data. Lake Reserv Manag. XXX–XXX. Bird species richness and lake area are highly correlated all around the world. In Florida, this relationship informs establishment of lake regulatory levels using a lake area threshold reduction of 15%, corresponding to loss of one waterbird species. This study demonstrated the efficacy of using citizen science (eBird) data to estimate waterbird species richness through comparison to professional data for 25 Florida lakes. Using eBird data for up to 721 lakes, several statistical approaches produced threshold estimates of lake surface area reduction of 10–16%. While the existing 15% threshold remains supported, a 12% threshold may be warranted for lakes with characteristics different from previous studies or for more conservative management. Methods for the use of eBird data to assess relative species richness differences, account for sampling effort, and establish regulatory thresholds may translate to other regions. While this approach considers one narrow aspect of lake ecology and should only be used as part of a suite of ecologic and hydrologic metrics, it can serve as a practical and critical backstop for lake protection.

ABSTRACT The natural environment is widely recognized as beneficial for human well-being. Limited research, however, has examined the combined influence of both biophysical and experiential measures related to the natural environment on subjective well-being. This study investigates how multiple environmental attributes including air quality, recent land cover change, biodiversity, extent and diversity of natural areas, psychological restoration, and outdoor recreation, relate to life satisfaction in the Puget Sound region, Washington, USA. We used linear models built on data from a regional survey (n = 1,372) to assess the direct and indirect effects of environmental features and demographics on life satisfaction. We found that psychological restoration and frequency of outdoor recreation had significant positive effects on life satisfaction. Of the biophysical attributes, recent increases in forest cover had significant positive effects on life satisfaction, particularly for long-term residents. While biodiversity and natural area characteristics had no significant effects on life satisfaction, they did have significant effects on psychological restoration and outdoor recreation, indicating indirect pathways of influence. Specifically, bird species richness and the proportion of natural area within the nearby landscape had significant positive effects on both psychological restoration and outdoor recreation. The diversity of natural habitats within the nearby landscape also had a significant positive effect on psychological restoration. These findings highlight the importance of integrating structural and experiential dimensions of nature in well-being research and underscore the need for equitable access to environments that support both recreation and psychological restoration.

Ecological studies quantifying the impact of land‐use change on biodiversity may be sensitive to the choice of reference points – or baselines – particularly when sampling across human land‐use gradients and other space‐for‐time comparisons. Much depends on whether the chosen baseline has already undergone shifts in species composition because of hunting, habitat loss and degradation. However, few studies have assessed the influence of shifting baselines on estimates of anthropogenic impacts. Using new survey data from five West African land‐use gradients, we examine how habitat patch size and structure influences the estimated impact of land‐use change on bird species richness and functional diversity. We show that smaller forests have already lost many forest‐dependent birds, particularly those with large body size or specialised ecological niches, leading to reduced estimates of biodiversity loss after deforestation. The steepest biodiversity loss was found in mid‐sized forests whereas relatively shallow declines were estimated for the most extensive forests – despite their richer taxonomic and functional diversity. In these larger forest blocks, accurate estimates of biodiversity loss may require longer transects extending beyond the biodiversity ‘shadow' caused by the more extensive spillover of forest species into the surrounding landscape, potentially linked to source–sink dynamics. These findings suggest that biodiversity assessments are highly sensitive to baseline selection and transect design, highlighting the risk of underestimating land‐use impacts unless shifting baselines are carefully considered.

Urbanisation is a major driver of changes in the configuration and composition of the landscapes, threatening biodiversity by reducing connectivity and simplifying ecosystems. This study examines the impact of variation in the structure and composition of urban landscapes on bird species richness and functional composition in Chetumal, Mexico. Through passive acoustic monitoring, we assessed bird species richness and, using Sentinel-2 satellite imagery, we calculated vegetation indices, spectral heterogeneity, texture, and landscape metrics to characterise habitat composition and configuration. Our results show that species richness decreased with increasing urbanization, with the forest landscape supporting more species than urban sites, particularly insectivores and shrub-foraging birds. The forest site was more aggregated and contiguous and had a higher effective mesh size, indicating greater structural connectivity. In contrast, urban sites were patchier and had more heterogeneous spectral signatures, reflecting landscape disaggregation. Functional composition of the bird communities also shifted, with urban sites harbouring more generalist species. Our findings highlight the importance of maintaining vegetated corridors and structural complexity to support ecologically diverse bird communities. The integration of acoustic biodiversity monitoring with spatial landscape metrics offers a powerful approach for mitigating biodiversity loss in rapidly expanding tropical cities.

Linkages between terrestrial and aquatic ecosystems offer important routes through which energy and marine-derived nutrients flow. These linkages serve to maintain ecosystem structure and function, and are essential aspects of the maintenance of the health of terrestrial ecosystems. The carcasses of anadromous salmonids are dispersed to terrestrial areas after spawning, and the nutrients in these carcasses are particularly important in the Northern Hemisphere. Terrestrial vertebrates, such as mammals and birds, mediate much of the nutrient transport through salmon carcasses and are therefore essential for maintaining the link between terrestrial and aquatic areas at the watershed scale. Urbanization has a strong impact on riparian communities, which interact with both terrestrial and aquatic ecosystems. However, few studies have been conducted on the effects of urbanization on these linkages with terrestrial vertebrate consumers that disperse energy over large areas. We investigated the effects of urbanization on scavenging avian communities and their total salmon carcass consumption in a salmon spawning river. We selected 17 study sites along 12 salmon spawning rivers in western Hokkaido, northern Japan. We recorded the number of scavenging birds of each species, and calculated the total salmon consumption by birds. We also calculated salmon carcass biomass, proportion of the urban area, channel width, and the distance from the coast. Based on these factors, we clarified the relationships between the abundance and species richness of scavenging birds, carcass consumption, and factors, using piecewise structural equation models. We found that both scavenging bird abundance and their total salmon consumption had unimodal responses to urbanization intensity. Our results suggest that urbanization has wide-scale effects on the strength of the linkages between ecosystems, including at the watershed scale. Suburban or peri-urban areas may also be important for maintaining local ecosystem functions.

Parasites are part of ecosystems and can regulate populations. The diseases they cause may negatively impact wildlife, sometimes linked to the imbalance created by anthropogenic environmental changes. Mexico harbors more than 10% of the world's avifauna, but there have been few studies on gastrointestinal (GIT) parasites in wild birds of Mexico. The aim of this review was to provide a comprehensive summary of knowledge on GIT parasites of Mexican wild birds and offer suggestions for approaches for future parasitological research on birds in Mexico. We analyzed 85 documents reporting gastrointestinal parasites in wild birds in Mexico. Overall, 73 genera and 96 bird species were reported as hosts for gastrointestinal parasites, representing approximately 8.17% of the bird species richness in Mexico, with the Anseriformes and Pelecaniformes being the most studied hosts. A total of 187 gastrointestinal parasite species have been identified to species level; the least studied phyla are Metamonada and Apicomplexa. Gastrointestinal parasites have been detected in 30 states; the central region of Mexico has been best studied. Game and aquatic species have been the most studied hosts, with few parasitological studies on nonaquatic bird species. Further studies are needed to understand the host-parasite relationships in Mexican landbirds, the diversity of parasites, the ecological factors underlying parasitism, and the impact of parasites in Mexican wild birds under anthropogenic changes.

Abstract Urban blue spaces are highly valuable for both people and nature. They provide key ecosystem services, including flood alleviation, pollution absorption and microclimate regulation. They also support human health and wellbeing, through cultural services such as recreation and tourism, and the provision of food resources. Crucially, urban blue spaces support biodiversity, including threatened species, and despite often being small, may have disproportionate effects on their surrounding environment, acting as critical habitats within urban systems. However, research on the role of urban blue spaces within ecological contexts remains limited. Here, we assessed urban bird communities across green and blue spaces to quantify the ecological effects of urban water bodies. We surveyed birds along 22 paired 1 km transects in the city of Kingston Upon Hull, UK, recording species and abundance across both winter and breeding seasons. Our findings indicate that blue spaces significantly increase bird species richness during summer (P = .016), though not in winter. However, we found that the taxonomic distinctiveness of bird communities is consistently greater around blue spaces across both seasons (P < .05). Similarly, functional diversity based on species-level ecological traits was higher around water (P = .01). In addition, we show that urban blue spaces could be important for avian conservation, supporting more red and amber-listed species than green spaces during the summer (P < .05). Overall, our results show that urban blue spaces play a critical ecological role within cities by enhancing the complexity of avian communities, which in turn could improve human wellbeing and contribute to urban sustainability.

To contribute to our growing understanding of the urban ecological filtering process in highly biodiverse regions, we conducted a study on bird species assemblages across the landscape of Medellín and its surrounding areas in the Colombian Andes. Nonurban land cover categories included well-preserved and second-growth forests, exotic-tree plantations, and open areas. Urban areas were categorized into four urbanization levels ranging from 0% to 100% built cover at intervals of 25%. Well-preserved and second-growth forests exhibited the highest bird species richness, followed by open areas, while the 76%-100% urbanization level displayed the lowest richness. Based on either taxonomic or functional composition, the bird assemblages across all urbanization levels resembled open areas. The other nonurban land cover categories shared a lower proportion of bird species with open areas and all urbanization levels, with well-preserved forests showing distinct compositions. These results suggest that bird species inhabiting open areas face a broad urban ecological filtering until reaching a threshold above 75% built cover, while birds inhabiting well-preserved forest face a narrow ecological filtering at the urban edge. Our findings provide insights into urban ecological filtering at the landscape scale and pose significant challenges for urban planners aiming to maintain favorable environmental conditions for highly biodiverse species pools.

Urbanization is a key driver of biodiversity change, yet little is known about the ecological patterns of overwintering bird communities and their drivers within boreal cities. Here, we assessed shifts in overwintering bird diversity in Lahti, southern Finland. Specifically, we analyzed city-wide changes in bird species richness and composition along an urbanization gradient, as well as the relationships between environmental and structural variables and recorded bird species richness and abundance. Our results show that overwintering bird species richness declines with increasing urbanization, with a pronounced drop beyond 60% built cover. Species abundance also decreased with urbanization, differing from previous findings in boreal regions. Most species recorded across our surveys were generalist granivores and omnivores, shared among survey sites. Although overall species composition showed moderately high dissimilarity, no clear patterns emerged across urbanization levels. Temperature and built cover were the only significant predictors of bird diversity. Temperature was positively associated with species richness, while built cover was negatively related with both species richness and abundance. Notably, our model for bird abundance had low explanatory power, suggesting unmeasured factors may influence patterns. Although our study is limited to a single city and year, it provides valuable insights into overwintering bird ecology in urban boreal environments. Our findings highlight the role of urban areas for overwintering birds and suggest that future research on mechanistic drivers, including human feeding, could inform urban planning strategies for non-urban bird populations.

<p>The study aims to compare the effectiveness of bioacoustic and point count methods in assessing bird species richness in Bukit Watu Ondo, Mount Ungaran, Central Java. A quantitative approach was employed through simultaneous data collection using both methods at six observation points. Bird observations were conducted visually and acoustically for 15-minute sessions at each point, repeated three times. The data were analyzed using a paired t-test to determine statistical differences between the two methods. Results showed that the point count method identified 29 species from 22 families, while the bioacoustic method recorded 25 species from 17 families. Statistical analysis revealed no significant difference (p = 0.927) between the two methods in the number of detected species, indicating comparable effectiveness. However, bioacoustics proved more efficient in detecting vocally active or cryptic species that were difficult to observe visually, whereas point count performed better for visually conspicuous species. The combination of both methods provided a more comprehensive representation of avifaunal diversity. These findings demonstrate that bioacoustic techniques are a viable and complementary alternative to traditional visual methods in biodiversity monitoring and conservation management.</p>

Fire is a pervasive biogeographic process that shapes biodiversity globally and is now experiencing unprecedented changes. Despite well documented impacts of fires on biodiversity, we do not know where biodiversity might be most vulnerable to changing fire regimes. We leverage recent advancements in fire forecasting and species distribution modeling to assess the exposure of bird species richness, community uniqueness, and functional richness to altered fire regimes in the western United States. We find that 55-58% of biodiversity hotspots are classified as "refugia", where high biodiversity intersects with predicted low severity burn areas. In contrast, 24-30% of biodiversity hotspots are classified as "areas of concern", where high biodiversity intersected with predicted high severity burn areas. Over half (52-60%) of "areas of concern" occur in geographies with historically low-severity fire regimes; a fire regime mismatch indicating a potential threat to biodiversity. We find that species with a preference for high-density vegetation and with shallower beak depth are most likely to be exposed to high severity fire, indicating a potential for habitat losses for species with these traits. Our findings reinforce calls for targeted management to reduce impacts of future fire where it is predicted to be outside the historical range of variation.

Abstract Urban development and deforestation have had a profound impact on ecosystems, resulting in fragmented landscapes and a decline in biodiversity. The Mata de Santa Genebra (MSG) in Campinas, São Paulo state, Brazil, exemplifies these challenges, serving as one of the last significant remnants of the Atlantic Forest in the region. This study investigates the avian diversity within MSG, focusing on bird species richness and their habits in this isolated forest fragment. Over 242 hours of observation, from December 2012 to November 2013, 181 bird species were recorded, which is 20.97% of the bird species in São Paulo and 47.75% in Campinas. This finding highlights the importance of MSG as a refuge for avifauna, despite its small size and isolation. The study reveals a dominance of open areas dwellers due to the fragment’s configuration and edge effects exacerbated by urban encroachment. Our observations include the presence of a hybrid manakin (Pipridae) and potential instances of local extinction, colonization and/or recolonization, emphasizing the need for ongoing monitoring. The forest edges, especially the wetlands at MSG provide critical resources for various bird species, underscoring the need to conserve these areas to maintain local biodiversity and ecosystem services. The results highlight the importance of habitat restoration, ecological corridors, and protection from anthropogenic pressures to ensure the preservation of bird diversity and ecological balance in fragmented landscapes.