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Several studies have revealed that urban rivers with relatively complete habitat structures can support a high level of biodiversity in urban areas. However, few studies have analyzed the impact of the plan, design, and management of multi-scale urban riverside green space on bird communities by assessing several aspects of diversity (e.g., taxonomic and functional). In this study, we explored bird community variation (taxonomic and functional) among three rivers (28 sampling sites) with different levels of human disturbance along the urban development gradient in Kunming, Yunnan Province, China, during an annual cycle. This study related bird species richness and functional diversity to environmental variables at three spatial scales: landscape metrics at two different landscape scales (500 and 100 m radius) and vegetation structure at patch scales (20 m radius). Using partial least squares regression (PLSR) and multiple linear regression, we found that bird species richness and functional diversity were strongly related to various landscape- and patch-level variables. Multiple linear regression models revealed that, compared with the richness influenced by explanatory variables on three spatial scales (500, 100, and 20 m), the functional diversity was significantly influenced by explanatory variables on the 100 and 20 m scales. Tree cover at the 20 m scale had significantly positive impacts on bird species richness and functional diversity. Forest land in the 100 m scale had a significantly positive effect on bird species richness and functional diversity, while construction land in the two landscape scales (the 500- and 100 m scales) had a significantly negative effect on species richness. Accordingly, we suggest that urban riverside green space should be planned and managed at multiple scales.

In recent decades, concern for migratory birds has stimulated research assessing the relationships between forest management and bird populations. The Missouri Ozark Forest Ecosystem Project (MOFEP) is a long‐term, landscape‐scale experiment designed to examine the effects of even‐aged (i.e., clearcutting), uneven‐aged (i.e., selection cutting), and no‐harvest forest management on ecosystem‐level processes. The management systems were randomly assigned to three sites each (mean area = 400 ha) with harvest occurring on a different portion of trees every 15 yr over a 100‐yr rotation. We used non‐metric multidimensional scaling and linear mixed models to investigate the effects of silvicultural treatment and year‐since‐harvest on bird communities over a 24‐yr period, before and after two harvests (1996 and 2011). Bird community compositions diverged among treatments immediately post‐harvest, but the differences in community composition and structure began to diminish by 8 yr post‐harvest. Species richness was higher in treated stands than no‐harvest controls and lowest approximately 10 yr post‐harvest regardless of treatment. Species diversity showed a linear decrease with year‐since‐harvest. Our findings demonstrate that even‐aged and uneven‐aged forest management can affect bird community composition and structure within the early post‐harvest period, but differences may diminish relatively quickly as harvested stands regenerate. We recommend using a variety of silvicultural methods to provide the diversity of habitats needed for the conservation of diverse forest bird communities.

A key aspect of monitoring regional changes in biodiversity is to quantify the temporal turnover in communities. Turnover has traditionally been assessed by observing range change. However, we are often interested in trends in biodiversity of large regions as opposed to single sites, as with Convention for Biological Diversity targets. Extinctions and colonizations tend to be rare events at the regional level; changes in species proportions estimated from spatio‐temporal models of species abundance are then more sensitive measures of community change. We investigated three measures for quantifying turnover based on species proportions, and estimated how each varies across Great Britain using data from the British Trust for Ornithology's Breeding Bird Survey. All three measures identify high turnover associated with loss of biodiversity in the south‐east of England. This seems to be driven by changes in the farmland bird community, and by turnover in the scarcer species of the woodland bird community. The measures also show evidence of high turnover in the west of Scotland; these changes may be linked to climate change, although precision in our measures for this region is relatively poor due to low survey effort. Policy implications. Turnover in ecological communities may be quantified by modelling species abundance, and measuring how resulting species proportions change over time. When used alongside estimated temporal trends in biodiversity, these can identify areas and communities showing greatest evidence for change. How, and indeed even whether, society should respond to such changes depends on further investigation into the causes of the changes, and the extent to which these are seen as undesirable and avoidable. For those communities with adequate survey data, we recommend that these methods augment the suite of measures used for routine assessment of change, hence acting as a more sensitive trigger to set in motion exploration of causes and consideration of adaptive actions to be taken by land managers and policymakers.

Mountain ecosystems are crucial for global biodiversity conservation. However, their landscape features are constantly changing owing to urban expansion. Understanding the relationships between biotic communities and landscape features is essential for biodiversity conservation. This study aimed to examine the effect of land cover type on avian communities in Lishui, a mountainous urban area in eastern China. Avian surveys were conducted using 168 line transects in total across different land cover types once per season from December 2019 to January 2021. We assessed the diversity of bird communities by calculating various metrics at both taxonomic and functional levels. Among the land cover types measured, woodland, built-up land, cultivated land, and water bodies significantly influenced bird community diversity and composition. Species richness, species abundance, and functional richness were negatively correlated with the proportion of woodland but were positively correlated with the proportion of non-natural land cover, such as built-up and cultivated land. In contrast, functional evenness was positively correlated with the proportion of woodland and grassland but negatively correlated with the proportion of non-natural land cover. Land cover type also exhibited significant correlations with avian functional characteristics such as diet, foraging strata, and body mass, thereby influencing the overall community structure. Our results indicated that mountainous landscape patterns substantially affect avian communities. Different land cover types possess varying resource endowments that affect the distribution of avian species. Therefore, urban landscape planning in mountainous areas should carefully consider the various functions provided to organisms by different types of land cover to promote biodiversity.

I studied population densities of forest bird communities in the Mariana Islands of Saipan, Aguiguan and Sarigan in order to evaluate hypotheses concerning seasonal shifts in populations, habitat effects on densities, inter-island differences in densities, social group size and underlying reasons for community structuring. With the exception of one species, I found no evidence to support the hypothesis that seasonal shifts occur in populations. Hence, this island system differs in this regard from mainland tropical forests. I also found, contrary to theory, no evidence that the presence of altered habitat permits populations to be greater than they would be in their absence, as disturbed habitat had far lower densities of most species than native forest. Furthermore, I found no support for the hypothesis that social group size differs seasonally as a consequence of differential breeding activity, which is again contrary to findings for mainland tropical forests. A high density of nectar resources on two islands appeared responsible for high population densities of the Micronesian Myzomela on them. Inter-island density comparisons showed strong evidence for there being unfilled niches on Sarigan, thereby making the island a favorable site for species translocations. Examination of the prehistoric composition of Marianas forest bird communities indicated that they once resembled in density structure those of the comparatively pristine Palau Islands. Removing ecologically similar but now absent species from the original Mariana communities likely resulted in reduced competition for resources in ways that increased niche breadth and, thus, populations. The wholesale loss of species in the Marianas has led to communities in which three ecologically versatile species now account for the vast majority of individuals in the community.

Studies assessing the effect of urbanization on bird community structure largely carried out in developed countries and little is known about the developing region particularly in India. Bird diversity, richness, composition and guild structure was examined at urban, semi-urban, semi-rural and rural-natural sites in Aligarh, Uttar Pradesh. Each site was sampled using 90 fixed radius point counts between January and June 2016. Semi-urban site was more species rich (2.38 ± 0.06), diverse (0.80 ± .01) and even (0.90 ± .00) than other three urban-rural gradient sites. Density of bird peaked at urban site (43.09 ± 4.7). Numerically, urban site was dominated by omnivore species which was replaced by insectivorous species at semi-natural, semi-rural and rural-natural sites. The current information corroborates the earlier studies assessing impact of urbanization of birds and Conell’s intermediate disturbance hypothesis of higher richness and diversity at intermediate disturbance. 

Background The composition of wild bird populations in temperate zones greatly varies depending on phenological changes rather than other environmental factors. Particularly, wild birds appearing in wetlands fluctuate greatly due to the crossover of species arriving for breeding during the summer and for wintering. Therefore, to understand the changes to species composition related to phenology, we conducted this basic analysis of populations to further the cause of the protection of wetland-dependent wild birds. Methods It is wrong to simply divide a wild bird population investigation into seasons. This study identifies species composition and indicator species that change along with seasons. Wetlands to be surveyed are protected by natural monuments and wetland inventory and are in a state close to nature. In order to identify as many species as possible in wetlands, a survey was conducted in both shallow and deep wetlands. The water depth varied in these areas, ranging from 0.2 to 2.0 m, allowing for both dabbling and diving ducks to inhabit the area. Surveys were conducted using line-transect and distance sampling methods and were conducted at intervals of 2 weeks. The survey was conducted under the following three categories: the eco-tone and emergent zone, the submergent zone, and the water surface. The survey was conducted along a wetland boundary by observing wild birds. A PC-ord program was used for clustering, and the SAS program was used to analyze the changes in species composition. The data strongly indicates that day length is the main factor for seasonal migration periods, despite the fact that climate change and increasing temperatures are often discussed. Results and conclusions The indicator species for determining seasons include migrant birds such as Ardea cinerea , Alcedo atthis , Anas penelope , and Poiceps ruficollis , as well as resident birds such as Streptopelia orientalis and Emberiza elegans . Importantly, increases in local individual counts of these species may also serve as indicators. The survey results of seasonal fluctuations in temperate zones shows that spring (April to June), summer (July to September), autumn (October), and winter (November to March) are clearly distinguishable, even though spring and summer seasons tend to overlap, leading to the conclusion that additional research could more clearly identify fluctuation patterns in species composition and abundance in the study area.

Invasive exotic species pose an important threat to biodiversity worldwide. However, there is little information on the effects that specific exotic bird species have on native biota. The House Sparrow is an excellent ecological model to evaluate the effect that an invasive exotic species has on native bird communities. Our study describes the relationship of the presence and abundance of House Sparrows with the structure, diversity, and composition of native bird communities in West Mexico. We used two approaches to compare House Sparrow invaded and non-invaded bird communities: (1) at a small geographic-scale that allowed us to evaluate shifts in avian communities with presence of the House Sparrow under similar environmental conditions; and (2) at the landscape-level to evaluate the effect of this species under a scenario of greater environmental heterogeneity. Results from both approaches show that areas invaded by House Sparrows have heavily-dominated avian communities with low species richness, while non-invaded areas exhibit highly-even and species-rich bird communities. Species turnover analysis indicates that the decrease in the number of bird species in House Sparrow invaded areas is caused by species loss, rather than a shift in species composition. Our results indicate that the invasion of an area by the House Sparrow, through synergistic interactions with human activities, determines the composition, structure, and diversity of native bird communities.

Birds are important components of karst forests. Their presence can be an indicator for habitat occupied. We identified bird communities in the karst forests of Teluk Sumbang, East Kalimantan. Bird sampling was done in hill karst forests and coastal karst forests. We employed a point count method by following transects. Observers walked constantly along transect and stopped every distance of ±200 m to record all sighted birds for 10-15 min. We found 89 bird species: 67 bird species were identified in hill karst forest and 33 bird species were recorded in coastal karst forests. Eleven bird species were found in both study sites. The score of diversity, species richness, and evenness indices of hill karst forests was higher than that in coastal karst. A t-test revealed that there was a significant difference in diversity index between coastal and hill karst (T = 2.016, p = 0.039). Birds characterized by a wide range of distribution and were able to adapt to various types of environments, particularly secondary forests, were most dominant. Nevertheless, the karst forests of Teluk Sumbang were also essential habitat for threatened and protected bird species. Keywords: Birds communities, Karst forests, Secondary forests, Sangkulirang-Mangkalihat.