Bird Species Richness Research Articles

Agroforestry supports high bird diversity in European farmland

Intensification and homogenization of agricultural landscapes have led to a strong decline in European farmland birds. Agroforestry systems, which were widespread in the past, are regaining attention as they could return structural heterogeneity to agricultural landscapes. However, few studies focus on the effects of such systems on biodiversity and especially bird diversity. We hypothesized that agroforestry systems host a higher alpha and beta diversity of birds compared to open agriculture as well as distinct bird communities. Moreover, we expected that bird communities in temperate Europe and the Mediterranean are differently affected by agroforestry systems. In this study, we assessed breeding bird diversity via audio recordings in nineteen mature agroforestry plots, comprising both silvoarable and silvopastoral systems distributed across seven countries in temperate and Mediterranean Europe. For comparison, bird diversity was also assessed in nearby open agricultural land, forests, and orchards. Bird species richness in agroforestry was more than doubled compared to open agricultural land and similar to the diversity found in forests and orchards. Community composition and within-habitat beta diversity differed between the habitat types and between European regions. While temperate agroforestry systems hosted generalist and woody habitat species, bird communities in Mediterranean agroforestry were composed of species from both open and woody habitats. Beta diversity was significantly higher in agroforestry than in open agriculture in temperate systems but not in the Mediterranean. Our study demonstrates that agroforestry systems represent a valuable habitat for breeding birds in European agricultural landscapes. A wider adoption of these systems could thus contribute to halting and reversing the decline in bird diversity, especially in temperate agricultural landscapes.

Pine plantations and native forest fragments adjacent to intact forests provide surrogate habitats for birds in an Afrotropical forest landscape

AbstractTropical forests harbour 72% of the world's bird species. The changing land uses have fragmented natural forests or replaced them with plantation forests. This sets in an argument as to whether forest fragments and plantations can support birds. We assessed birds in a plantation, fragment and an intact (continuous) Budongo forest, Uganda. We compared bird species composition, diversity and functional traits between the forests and examined their response to habitat characteristics. We sampled birds using 135 point counts along nine transects and assessed habitat characteristics in 90 plots in the fragment and intact forest. We classified bird species according to habitat preference and feeding guild. Bird species composition differed between forests. Bird abundance and richness in plantation and fragment were lower than in intact forest. Forest specialists and insectivores dominated the intact forest. Most birds in the fragment were forest generalists and frugivores. Forest visitors and granivores dominated in the plantation. Trachyphorus purpuratus, Andropadus latirostris and A. curvirostris preferred sites with greater tree height, diameter and many snags, respectively. Bird species abundance and richness declined with increasing tree diameter and increased with snags. Forest specialists preferred sites without climbers. Thus, plantations and fragments close to intact forests provide surrogate habitats for bird conservation.

Bird species richness and habitat guilds at isolated forest patch in Turahalli Minor Forest, Bengaluru, Karnataka, India

Analyzing habitat preferences and foraging dynamics can be useful in understanding how birds adapt to changing physical environments. This is the first-ever study that was carried out on Avian feeding and Habitat guild of the Turahalli minor forest. Our study compares foraging patterns and habitat preferences among bird species by using One-way ANOVA, Tukey’s multiple comparison test, Kruskal-Wallis test and Mann-Whitney U tests. Observations based on habitat and diet affinities accounted for rich avian diversity with a total of 139 bird species recorded from five different habitats from October 2020 to November 2022. Large trees (95 species) harbored more species followed by shrub and thorny (30 species) and open ground (8 species). Bird assemblages were richer in large tree habitats and shrub and thorny habitats and findings showed that there was no significant difference in bird species richness between the habitats. Insectivorous species (39%) and carnivorous species (30%) exceeded other feeding guilds in the study area. Results of the study showed that different functional groups of avifauna behaved differently, primarily persuaded by choice of food. By providing birds with stable foraging, roosting, and nesting options, habitat heterogeneity supported avifaunal persistence.

Potential implications of shortened rotation length for forest birds, bryophytes, lichens and vascular plants: An example from southern Swedish production forests

The rotation lengths of intensively managed production forests may be altered to achieve a variety of goals, with correspondingly implications for biodiversity. Here we consider the potential implications of shortened rotation times for biodiversity in planted monocultures of the two most common production tree species in Sweden, Scots pine (Pinus sylvestris) and Norway spruce (Picea abies). To do so we surveyed bird, bryophyte, epiphytic lichen and vascular plant diversity in 80 and 55-year-old stands; stand ages which approximate present-day and potential future rotation lengths in this region respectively. We found clear differences in the species communities of the 55 compared to the 80-year-old stands for both understory species and epiphytes, but not for birds. Nevertheless, bird species richness was still highest in the 80-year-old Norway spruce dominated stands. Dead wood amount was also highest the 80-year-old Norway spruce stands. Highest species richness of epiphytic lichens was found in 80-year-old Scots pine stands. However, 55-year-old Scots pine stands had a higher understory species richness and diversity than the older Scots pine stands, including a larger number of open land species. The 80-year-old forest stands examined may be considered old with respect to production forest rotation lengths in Sweden but are relatively young when comparing stand ages of unmanaged natural forest stands. Nevertheless, our results indicate that shortening the rotation time of Scots pine and Norway spruce, in this part of Sweden from 80 to 55 years, could have important consequences for forest biodiversity. These consequences are primarily inferred from the likely implications from shortened rotations for lichens community composition and diversity in both Norway spruce and Scots pine stands, as well as impacts on understory plant species in Norway spruce stands.

The transformation of river ecosystems caused by mining affects bird breeding in indigenous riparian habitats

Our study considered the excavation of sand and gravel, which modifies the landscapes of riparian ecosystems. It promotes the creation of water bodies with surrounding vegetation, but it also results in the loss of natural habitats.We investigated the species richness, composition, and abundance of aquatic and terrestrial breeding birds and their interaction with three habitat types: managed and abandoned flooded pits, and oxbow lakes. We surveyed 117 sites in medium-sized river valleys in the foreground of the Bohemian Massif (Czech Republic), and in the Carpathian Mountains (Poland, Slovakia) in 2022.Flooded pits were suitable for open-water and colonial birds. Managed flooded pits were also suitable for early successional land birds, but they did not provide habitat for birds that use marshes and wet meadows, or riparian woodlands. The majority of species preferred to breed in oxbow lakes with riparian forests and these areas hosted the highest number of threatened species.We concluded that high levels of disturbance in riparian ecosystems promoted some birds (e.g. colonial or breeding in early-successional habitats), but it negatively affected the overall bird diversity, and it led to a species composition shift with the elimination of taxa associated with indigenous riparian habitats. The importance of flooded pits increases with subsequent plant succession. Our results indicate that gravel or sand mine pits, although beneficial for some taxa, are not substitutes for natural habitats in riparian ecosystems, as they do not support birds breeding in indigenous riparian habitats. Natural oxbow lakes with riparian forests are habitats that need to be preserved to effectively promote local biodiversity.

Evidence that species richness begets species richness

AbstractAimThe variability in regional species richness is determined by the balance between speciation, extinction, and migration, but the underlying causes of high species richness in some regions (e.g. tropics, Mediterranean ecosystems) are challenging to explain. Species richness variability may be amplified by biotic feedbacks that promote species richness in some areas, while decreasing elsewhere. Following the example of species abundance, we speculated that species richness per area in arbitrary geographic units (e.g. quarter‐degree squares) follows a hollow‐shaped curve with the ranks of species richness to yield a species richness rank (SRR) curve. The hollowness of such an SRR curve may indicate biotic feedbacks.LocationSouth Africa, South West Australia, and global.Materials and MethodsWe used vascular plant (VP) and bird data from distinct geographic regions and global syntheses of VP, bird, mammal, and amphibian species richness. These data were subdivided into geographic grids and the deviation from normality of the species richness quantified using skewness and kurtosis and the values ranked to yield SRR curves.ResultsThese SRR curves all had a consistent hollow shape (corresponding skewness 1.08–3.4, kurtosis 0.23–18.40) distinct from a normal distribution arising if species were allocated randomly to geographic units. The SRR curves indicate that relatively species‐rich regions are rare, while species‐poor areas are common.Main ConclusionsNeutral processes, abiotic determinants, environmental heterogeneity, historical factors (e.g. climate stability), and biotic feedbacks all likely play a role in contributing to the shapes of the curves. Although these curves for diverse taxa and regions integrate these multiple drivers of species richness, they indicate an acceleration of species richness as a function of species richness as a result of speciation and/or immigration, limited by increasing extinction likelihood. Biotic feedbacks provide a parsimonious explanation for the shapes of the SRR curves across taxa and regions.

A cross-sectional analysis of biodiversity, publicly accessible green space and mental well-being in Wales using routinely collected data

There is a lack of studies investigating the effects of green space and biodiversity on mental well-being, across a large study area. Generally, exposure to natural environments promotes better physical health, mental health and well-being. This study investigated associations between publicly accessible green space, biodiversity and mental well-being for individuals living in Wales using routinely collected survey and biodiversity data. This study used the Warwick-Edinburgh Mental Well-Being Scale (WEMWBS) to measure mental well-being. The 2018–19 National Survey for Wales responses containing the WEMWBS scores and socio-demographic factors were linked to green space and biodiversity data in census areas. By utilising Generalised Additive Models this study found that all environmental metrics were associated with mental well-being. However, after adjustment for socio-demographic factors, only bird species richness remained associated with mental well-being, with a highly non-linear relationship. There was little to no evidence of associations between green space or biodiversity when stratifying by income group. When stratified by rural and urban areas, we found bird, plant and total species richness to be associated with mental well-being.Environmental interventions should consider promoting bird species richness in urban areas which may benefit mental well-being. Future areas of research could include longitudinal studies to explore causal links between green spaces, biodiversity and mental well-being, utilising individual-level exposure.

Elevational patterns of species richness and community structure of understorey birds in an East African montane forest

AbstractMt. Kasigau is the northeastern most of the Eastern Arc Mountains global hotspot and harbours some endemic and threatened species, but little is known about bird community changes along its elevational gradient. We assessed the relationship between bird biodiversity metrics, season, human disturbance, elevation and temperature using mist‐netting data collected bi‐annually over a 10‐year period. Birds were sampled along the mountain's elevational gradient at four elevation levels (858, 1104, 1321 and 1547 m). Bird richness, diversity and evenness decreased with increasing altitude in both dry and wet seasons. Bird abundance declined with increasing elevation for the lower three elevation levels but peaked at the highest elevation. All diversity metrics were higher in the wet season compared to the dry season across all the years. Elevation had a greater effect on species assemblages than season, disturbance and temperature. Temperature had significant effects on abundance, diversity and richness, while disturbance had significant effects on diversity, evenness and richness. We conclude that bird assemblages in Mt. Kasigau are strongly shaped by elevational changes, while temperature and disturbance constitute important factors influencing bird conservation in the face of global warming. Our study highlights that elevation, disturbance and temperature influence bird assemblages along tropical elevational gradients.

Use of epiphyte by bird communities in IPB Dramaga campus

Epiphytes have a direct or indirect influence on terrestrial ecosystems. The presence of epiphytes can increase habitat complexity vertically and benefit animals, especially birds. The objectives of this study were to identify the species of epiphytes, their host trees, and the birds and to analyze how composition of epiphytes and host trees affects the diversity and abundance of birds. The research was conducted in seven sites within the IPB Dramaga Campus from December 2022 to February 2023. We collected biotic data (the number and type of epiphytes, host trees, and birds) and abiotic data (temperature and humidity) at each site. We used Paleontological Statisctic (PAST) to calculate the diversity index and R software to examine the correlation between birds and epiphytes. We found a significant positive correlation between the species richness of epiphytes, host trees, and birds. The sites with the highest diversity and abundance of trees, epiphytes, and birds were Conservation Park and Campus Forest Park. Sites with more diverse and abundant epiphytes had lower temperatures on average. We observed four bird species that used epiphytes: Pycnonotus aurigaster, Aegithina tiphia, Sitta frontalis, and Dicaeum trochileum. These species foraged for invertebrates on or near the Asplenium sp. epiphytes.

Plant functional composition as an effective surrogate for biodiversity conservation

In biodiversity conservation frameworks, determining surrogates for biodiversity is crucial for improving the effectiveness of biodiversity conservation and management. As plant functional composition can indicate variations in ecosystem functions and services, it could be used as an effective surrogate in biodiversity conservation planning. However, to the best of our knowledge, this metric has been rarely used in biodiversity conservation planning. To explore whether plant functional composition can be used as an effective surrogate for biodiversity conservation, we used a linear mixed regression model to investigate the relationships between plant functional composition (i.e., community-weighted means (CWMs) from the sPlot database) and the species richness of birds, mammals, and amphibians, and between plant functional composition and terrestrial conservation priority ranks (considering biodiversity conservation alone, or biodiversity, carbon, and water conservation together). Thereafter, we quantified the changing trends in these relationships across biomes using the least square method. We found that CWMs significantly affected species richness and terrestrial conservation priority ranks, based on the marginal R2 and conditional R2 values from the linear mixed regression model. Further, CWMs significantly affected species richness and terrestrial conservation priority ranks across different biomes of forests and shrublands. However, the nature of these effects (i.e., positive or negative) was dependent on biome type. These results suggest that functional composition can be considered as a biodiversity surrogate for conservation planning, and that biome-specific relationships should be considered.

The Influence of Grazing Systems on Bird Species Richness and Density in the Nebraska Sandhills

Grazing is the de facto method of habitat management used in much of the Nebraska Sandhills. Ranchers use a variety of grazing systems, and our goal was to evaluate the effects of systems on grassland birds. We estimated the species richness and density of grassland birds for three grazing systems used on private ranches: long, medium, and short duration grazing systems. We observed sixty species, and the grazing system with pastures utilizing long duration grazing periods had the highest estimates of species richness as well as the most heterogeneous habitat structure. Differences in species richness among systems were most pronounced in years of limited precipitation. Together, grasshopper sparrows (Ammodramus savannarum), western meadowlarks (Sturnella neglecta), and brown-headed cowbirds (Molothrus ater) accounted for 72% of our observations. We used a model comparison approach to determine the effects of habitat on the densities of six species. Densities of grasshopper sparrows and mourning doves showed effects of the grazing system. More species had higher densities in short duration, rotational systems than other grazing systems. However, species of grassland birds showed responses to a variety of cover types and habitat structures depending on life history needs. Regardless of the grazing system used, managers can use grazing and other tools such as prescribed burning to maintain habitat heterogeneity to support diverse bird communities.

Blue-green infrastructure and biodiversity: Urbanization and forestation have an important influence on bird diversity in water habitats

Water and forest habitats are an indispensable part of the blue-green infrastructure, a network that provides solutions for urban climatic challenges by building with nature. We were interested in the effect of water areas and the surrounding environment on bird species richness; specifically, we studied the influence of different levels of urbanization and related forestation. We focused on water, arboreal and ground bird assemblages in forested and nonforested water habitats in a 2000 km2 lowland area of Polabí in the Czech Republic at three urbanization levels: (i) urban, (ii) rural and (iii) open landscapes. The results revealed that ground birds were positively influenced by urban areas, while arboreal birds benefitted from surrounding forestation and tree vegetation on water banks. Overall, the results for native bird assemblages were not different, except that native water birds appeared to thrive in no settlement. The positive relationship between ground birds and urbanization and the weak negative relationship or lack of relationship between urbanization and the other groups were somewhat unexpected. The most likely reason is that water habitats are not as homogenized as other urban habitats. Surrounding forests could also help buffer the influences of urbanized areas. We conclude that blue-green infrastructure is also an essential environment for many birds.

A novel, post-Soviet fire disturbance regime drives bird diversity and abundance on the Eurasian steppe.

Many grassland ecosystems and their associated biodiversity depend on the interactions between fire and land-use, both of which are shaped by socioeconomic conditions. The Eurasian steppe biome, much of it situated in Kazakhstan, contains 10% of the world's remaining grasslands. The break-up of the Soviet Union in 1991, widespread land abandonment and massive declines in wild and domestic ungulates led to biomass accumulation over millions of hectares. This rapid fuel increase made the steppes a global fire hotspot, with major changes in vegetation structure. Yet, the response of steppe biodiversity to these changes remains unexplored. We utilized a unique bird abundance dataset covering the entire Kazakh steppe and semi-desert regions together with the MODIS burned area product. We modeled the response of bird species richness and abundance as a function of fire disturbance variables-fire extent, cumulative burned area, fire frequency-at varying grazing intensity. Bird species richness was impacted negatively by large fire extent, cumulative burned area, and high fire frequency in moderately grazed and ungrazed steppe. Similarly, overall bird abundance was impacted negatively by large fire extent, cumulative burned area and higher fire frequency in the moderately grazed steppe, ungrazed steppe, and ungrazed semi-deserts. At the species level, the effect of high fire disturbance was negative for more species than positive. There were considerable fire legacy effects, detectable for at least 8 years. We conclude that the increase in fire disturbance across the post-Soviet Eurasian steppe has led to strong declines in bird abundance and pronounced changes in community assembly. To gain back control over wildfires and prevent further biodiversity loss, restoration of wild herbivore populations and traditional domestic ungulate grazing systems seems much needed.

Island biogeography of mixed‐species bird flocks: A gregarious nuclear species influences island area effects

AbstractAimIsland biogeography theory has been extended to include various species interactions, but has yet to consider intraguild mutualisms. We compare species‐area relationships for mixed‐species flocks to those for the entire bird community and determine how ‘nuclear’ species, those important to flock formation or cohesion, which often have functional traits such as intraspecific gregariousness, influence flock species richness. We hypothesized that mixed flocks would only form on large islands where nuclear species are present. On the subset of larger islands, we expected flock species richness to rise with island area, reflecting a larger pool of species.LocationThirty‐one islands of varying area in the reservoir system of Thousand Island Lake, China.TaxonThe resident forest bird community and its subcomponent of flock participants. Similar to elsewhere in southern China, the primary nuclear species was Huet's Fulvetta (Alcippe hueti), which averaged 20 individuals per flock, and led the flocks when present.MethodsBirds were surveyed in the winter of 2017 and the autumn of 2021.ResultsThe probability for a flock to be present, and the species richness of birds per transect, increased with island area, but the species richness of flocks did not. Flocks with Huet's Fulvetta were only found on islands larger than 30 ha. Flocks on smaller islands formed around secondary nuclear species typical of northern Chinese flocks.Main ConclusionGregariousness as a functional trait may make nuclear species more susceptible to disappearing in small fragments, leading to flock collapse. The extreme gregariousness of fulvettas may also act to increase competition in the flocks they lead and limit the flocks' species richness. We encourage further comparisons of the species‐area curves of mixed‐species flocks and whole bird communities to better understand the influence of flocks on community assembly and species diversity.

Classification and distribution of functional groups of birds and mammals in Mexico.

There has been a recent exponential growth in the study of functional trait ecology. Nonetheless, the study of functional traits and functional groups has been limited for terrestrial vertebrates. We conducted a classification update of functional groups (FG) of birds and mammals in Mexico, and determined the distribution patterns of FG species richness in different ecosystems nationwide. We selected six functional traits (feeding habit, locomotion, feeding substrate and technique, activity period, seasonality, and body size) obtained for 987 and 496 species of birds and mammals, respectively. A cophenetic correlation analyses resulted in values of 0.82 for the bird species dendrogram, and 0.79 for the mammal species dendrogram showing that the structures adequately reflected the similarity between observations. We obtained 52 FG for birds, assembled into 9 broader groups based on their feeding habits (16 invertivores, 6 carnivores: 5 herbivores, 9 aquatic vertivore/invertivore, 5 granivores, 1 scavenger, 3 nectarivores, 4 frugivores, and 3 omnivores). We obtained 35 FG for mammals, assembled into 9 broader groups based on their feeding habits (4 granivores, 10 herbivores, 1 nectarivore, 4 frugivores, 8 invertivores, 3 omnivores, 2 aquatic vertivore/invertivore, 1 hematophagous, and 2 carnivores). Overall, the distribution of FG species richness for birds and mammals gradually increased from the Nearctic to the Neotropical region, following a typical latitudinal species richness pattern. Few FG of migratory birds, and FG of granivore and herbivore mammals showed more species in the Nearctic and in the transitional regions. Our study provides a baseline for identifying ecological functions of species of birds and mammals in different ecosystems in Mexico, and contributes to understand the relationship between species diversity, community structure and ecosystem functioning. Identifying spatial patterns of functional trait diversity is important as biodiversity loss has a negative impact on ecosystem functioning and provision of environmental services.

Differential utilization of surface and arboreal water bodies by birds and mammals in a seasonally dry Neotropical forest in southern Mexico.

Water availability significantly influences bird and mammal ecology in terrestrial ecosystems. However, our understanding of the role of water as a limiting resource for birds and mammals remains partial because most of the studies have focused on surface water bodies in desert and semi-desert ecosystems. This study assessed the use of two types of surface water bodies (waterholes and epikarst rock pools) and one arboreal (water-filled tree holes) by birds and mammals in the seasonally dry tropical forests of the Calakmul Biosphere Reserve in southern Mexico. We deployed camera traps in 23 waterholes, 22 rock pools, and 19 water-filled tree holes in this karstic region to record visits by small, medium, and large-bodied birds and mammals during the dry and rainy seasons. These cameras were set up for recording videos documenting when animals were making use of water for drinking, bathing, or both. We compared the species diversity and composition of bird and mammal assemblages using the different types of water bodies by calculating Hill numbers and conducting nonmetric multidimensional scaling (NMDS), indicator species, and contingency table analyses. There was a greater species richness of birds and mammals using surface water bodies than tree holes during both seasons. There were significant differences in species composition among bird assemblages using the different water bodies, but dominant species and diversity remained the same. Terrestrial and larger mammalian species preferentially used surface water bodies, whereas arboreal and scansorial small and medium mammals were more common in arboreal water bodies. These findings suggest that differences in water body characteristics might favor segregation in mammal activity. The different water bodies may act as alternative water sources for birds and complementary sources for mammals, potentially favoring species coexistence and increasing community resilience to environmental variation (e.g., fluctuations in water availability). Understanding how differences in water bodies favor species coexistence and community resilience is of great relevance from a basic ecological perspective but is also crucial for anticipating the effects that the increased demand for water by humans and climate change can have on wildlife viability.

Bird species richness and abundance in remnant eucalypt forest on the Southern Tablelands of New South Wales: A removal experiment

ABSTRACT Birds were removed after counting numbers along a creek reserve established when old growth eucalypt forest on the Southern Tablelands of New South Wales was cleared for pine plantations. Removal ceased after the number of individuals collected exceeded the number estimated by census to be present. Removal was followed by rapid recolonization probably from a large area of uncleared forest continuous with the reserve. This is similar to results obtained in removal experiments in North America which found the bird community contained ‘surplus’ or ‘floating’ individuals that immediately occupied vacant habitat. The large number of ‘floaters’ we identified by collection on the creek reserve assists in explaining the rapid recolonization by birds of habitats affected by wildfires and has significant conservation benefits.

Drivers of functional and phylogenetic structures of mountain bird assemblages along an altitudinal gradient from the montane to alpine zones

Understanding the process underlying the spatial gradients in biodiversity is a fundamental issue in ecology. Altitudinal gradients are ideal systems for examining the community assembly process because they represent rapid changes in environmental conditions over relatively short distances. The functional and phylogenetic approaches allow a deeper mechanistic understanding of the underlying assembly process. However, whether community assembly from montane to alpine zones is driven more by ecological constraints or human settlement patterns is not fully resolved and may vary by system. Here, we examined the phylogenetic and trait-based functional structures from the montane to alpine zones and clarified the effects of natural environmental factors and human-induced landscape transformation on the breeding bird assemblage on Mount Norikura, central Japan. Breeding birds from 700 to 3026 m a.s.l. were surveyed in 2016–2017. Bird community structures were examined based on species richness, functional and phylogenetic structures. A null modelling approach was performed to examine functional and phylogenetic cluster/overdispersion structures; clustering and overdispersion imply species elimination by environmental filters and limiting similarity as a corollary of competitive exclusion of species, respectively. Furthermore, we examined the relative effect of natural environments and human disturbance. Bird species richness was high in the mountain base to mid-elevation, then decreased with elevation. We found a contrasting pattern in the phylogenetic and functional structures in the alpine zone: phylogenetic overdispersion and functional clustering. In contrast, the functional and phylogenetic structures were clustered in the upper parts of the subalpine zone. The functional and phylogenetic clusterings in the lower parts of the subalpine and montane zones were negligible with the weak effects of the environmental filtering. Single-trait analysis showed that the high abiotic tolerance and foraging or nesting capabilities in treeless environments were clustered in the alpine zone, and mobility was clustered in the subalpine zones. Natural environments strongly affected bird community structures, but human disturbance added species to assemblages in the mountain base to mid-elevation and changed the functional and phylogenetic structures. Our findings highlight that filtering by severe natural environments is a fundamental community assembly process in high mountain regions, whereas filtering effects can be weaker at lower elevations. Furthermore, the filtering effect should differ between the alpine and the upper parts of the subalpine zones because of different combinations of clustered traits. Climate change and landscape transformation pressures may strongly impact biodiversity in the alpine and subalpine zones, respectively.

Infrastructure and the ethnographic-cartographic production of urban bird species richness

The qualitative bio-geographies of human geographers and the quantitative mappings of biogeographers share a goal: how to understand living with non-human life. Yet they rarely bridge the conceptual and methodological gap between them. This article theorizes how the concept of infrastructure can bridge this ethnographic-cartographic divide. Infrastructure is not just inert shell. It is also a system of relation, a dynamic patterning of socionatural form emerging out of experiences and affective moments of its constituents. As proof of concept, we quantified and compared urban bird species richness and frequency for Tallahassee, Florida over a 17-year period (2000–2017) for two co-occurring observational infrastructures, eBird and a wildlife rehabilitation center that serves the city. Species common to both infrastructures comprised 94% of all eBird observations and 99% of all rehab records. Their differences reflected contrasts in how the motivations for experiencing birds intersected with bird habitat preferences, behavior, and contingencies of urban history and development. eBird observations had a higher species richness (295 spp) and reflected the growing popularity among birds and a small number of active birders for visiting stormwater retention lakes recently modified to improve bird habitat. Rehabilitation records had a lower richness (194 spp) and exhibited a much more even distribution of bird encounters among individual residents as well as community institutions like schools, universities, law enforcement, and other government organizations. Infrastructural perspectives convey how affective and individualistic encounters with the non-human can link to emergent biogeographic mappings and how urban biodiversity is relationally and heterogeneously produced rather than simply contained in cities.

Global change impacts on bird biodiversity in South Asia: potential effects of future land-use and climate change on avian species richness in Pakistan.

Evaluating the impact of future changes in land-use and climate on species communities, especially species richness, is one of the most important challenges of current research in ecology and conservation. The impact of environmental changes on species richness depends on its sensitivity (i.e., how strongly a given level of change influences the ecological community) and its exposure (i.e., the amount of change that occurs). To examine the sensitivity, exposure, and potential impact of future environmental conditions on bird communities, we compiled data on bird species richness for Pakistan-a neglected region in macro- or country-scale studies. Since bird species richness strongly varies across seasons due to the seasonal occurrence of migratory species in winter, we compared both wintering (migratory plus resident species) and breeding (resident species only) bird richness. We found breeding and wintering species richness to be sensitive to temperature, precipitation and rainfed cropland by being positively related to these factors. Exposure varied regionally, with projected temperature changes being most profound in northern regions while the strongest projected precipitation changes occurred in central and southern regions. The projected impact of future environmental change were highly heterogeneous across the country and differed between the wintering and breeding communities. Overall, the most negatively impacted region was projected to be the Khyber Pakhtunkha province in the North of Pakistan, due to reductions in precipitation and rainfed cropland, resulting in a projected negative impact, especially on wintering species richness. By highlighting the regional and seasonal bird communities most at risk, our findings provide useful information for policy makers to help devise new policies for mitigating negative impacts of future environmental changes on birds within Pakistan.