Differences In Bird Diversity Research Articles

The public–private divide and seasonal variation shape bird diversity in greenspaces of two neighboring midwestern USA cities

Greenspaces are increasingly valued for supporting biodiversity in urbanized landscapes. Previous research efforts have emphasized the importance of public land such as parks and nature preserves for biodiversity, yet private yards in residential neighborhoods also have great potential for species conservation. Our study considered the importance of adjacent public and private greenspaces for urban bird diversity. We surveyed birds in public parks (n = 39) and private yards (n = 41) distributed across neighboring twin cities (Champaign and Urbana) in Illinois, USA, to assess potential differences in bird diversity across: (1) the public–private divide; (2) seasons (winter vs. summer); and (3) the two cities. We found a seasonal interaction across the public–private divide. In summer, communities in private yards were a subset of those found in public parks, whereas in winter, both private yards and public parks hosted equally diverse yet distinct species assemblages. Between the two cities, Urbana supported greater bird diversity and a distinct species assemblage compared to the warmer, more urbanized city of Champaign. Our results demonstrate that both public parks and private yards play key roles in supporting native bird diversity, but also highlight that these roles can shift across seasons. Furthermore, we show that neighboring cities within the same conurbation can differ substantially in bird community structure and diversity. Our findings reinforce the importance of maintaining heterogeneous landscape mosaics and combining land sparing and land sharing approaches to maximize bird diversity in urban areas.

Avifaunal diversity of Tsirang District with a new country record for Bhutan

Birds play a vital role in ecosystems. Studying avifaunal diversity therefore has a noteworthy role in indicating nature’s ecological balance in the environment. A total of 749 bird species have so far been recorded in Bhutan. We present a comprehensive checklist of birds of Tsirang, District which largely lies outside Bhutan’s protected area system. The data was collected through opportunistic encounters and with regular field visits to a range of locations in different seasons. One-fourth of the country’s total avifauna and a new species recorded for Bhutan, The Plum-headed Parakeet Psittacula cyanocephala was recorded as part of this study. In all, 285 avian species belonging to 18 orders and 65 families including one globally ‘Critically Endangered’, three ‘Vulnerable’, and a ‘Near Threatened’ species were recorded during the survey. The high species richness of birds in the study area reveals that it includes good habitats for birds in Bhutan. Similar studies are suggested in other areas contiguous to the protected areas in Bhutan including the current study area. This should aid in understanding of the factors driving the differences in bird diversity within and outside the protected areas so as to facilitate informed conservation actions in future.

Bird community structure and habitat association in Owabi Wildlife Sanctuary, Ashanti Region (Ghana)

Context Globally, an estimated 1.3% of the bird species have gone extinct over the past millennia, largely owing to habitat loss. Aims This study investigated bird–habitat associations and assemblages in the Owabi Ramsar wetland. Methods The study was conducted over 5 months (May–September 2019) in four habitat types (agricultural land, built-up, forest reserve, and open-water area). Data were collected in 84 plots across four habitats (i.e. built-up area = 25, forest reserve = 25, agricultural land = 25 and open-water area = 9 plots), using a point-count technique. The Gambin model, non-metric multidimensional scaling, Chao-1, and Hill numbers models were used to evaluate differences in bird diversity and composition among the habitat types. Key results In all, 1260 individual birds, belonging to 81 species, were encountered. Many of the species occurred in the forest habitat (n = 46, 56.8%. Species from the agricultural land (n = 37) and built-up (n = 30) were mainly habitat generalists that used these two habitats as their shared feeding station. Bird–habitat specialisation grouping equally showed the forest specialists to be the highest (n = 23, 38.4%), whereas the open water had the least number of habitat specialisation associations (e.g. white-faced whistling duck, n = 20, 24.7%). Five species were widely distributed in all four habitats (e.g. bronze-mannikins and white-throated bee-eaters), indicating their broad habitat preferences and ability to adapt to varied conditions. The forest reserve tended to be the most diverse, which was likely mediated by factors such as nesting microhabitats, varied food availability, and human-led activities. Conclusions This study highlighted bird dietary structure and associated habitat type and bird-habitat specialisation in four different land-use types at Owabi Ramsar wetland. Implications Given the increasing level of disturbance, there is the likelihood that the population of forest-dependent and open water-dependent birds will be lost or will have to change or modify their behaviour to be similar to that of open-tolerant or open-country birds if managers of the Owabi Wildlife Sanctuary fail to implement the recommended management interventions highlighted.

Relationship between Vegetation Habitats and Bird Communities in Urban Mountain Parks.

Simple SummaryThe complexity of urban green space vegetation is an extremely vital influential factor and predictor of biodiversity, and vegetation habitat factors have been shown to explain more variation in bird diversity than other environmental factors. In this study, we explored the characteristics and differences in bird diversity among vegetation habitats in five typical urban mountain parks in coastal areas of southeast China. Our study showed that: (1) Sparse forest supports more bird species and higher bird diversity. (2) Tree diversity significantly affects bird diversity in urban mountain parks. (3) The average subbranch height of trees has a significant effect on the evenness of birds. (4) The number of tourists and predators has little impact on bird diversity. This study could provide suggestions for the rational allocation of vegetation in urban mountain parks in southeast coastal areas to improve local ecological service functions as habitats for urban wildlife, especially wild birds.The coastal areas of southeast China have typical high-density urbanization characteristics, and urban mountain parks are important green spaces in these urban green space systems. Our study was conducted in five typical urban mountain parks in Fuzhou, China. The bird survey was carried out in 25 transects of different vegetation habitats for 10 months, and the vegetation survey was conducted in 25 habitats to investigate the characteristics of bird communities in different vegetation habitats and the causes of their differences. The results showed: (1) From 1 October 2021 to 15 July 2022, we recorded a total of 90 bird species in 8 orders, 37 families, and 64 genera, with 1879 individuals in five vegetation habitats in the urban mountain parks. (2) Abundance and diversity of trees are vegetation variables affecting bird diversity (bird species richness, abundance, and Shannon diversity) in urban mountain parks, and the average branch height under trees has a significant effect on bird evenness. (3) We found more bird species and higher bird diversity in both sparse and dense forest habitats, but fewer bird species in waterfront, shrub, and grassland habitats; (4) Average tree height (AVE_HEIt) was only present in the best model of bird abundance and evenness. However, none of the best models found a significant effect of the number of tourists and predators on bird diversity. Our results could provide a theoretical basis and guidance for the future improvement of ecological service functions of bird habitats in urban mountain parks in subtropical coastal areas.

BIRD AND ARTHROPOD COMMUNITIES IN FRAGMENTED HABITAT OF TERNATE

Habitat loss and fragmentation affect bird communities. Edge area created by fragmentation can affect bird communities through availability of arthropod. The objectives of this study are to examine whether there is any difference in bird diversity and abundance between different plantation types and location between fragments, and to examine if there is any correlation between arthropod and birds. To record Bird community was recorded using point count method with a distant between points 50 m and a fix radius of 25 m in each point for 10 minutes observation. Observation points were placed in each of edge and interior habitat of Cocos nucifera plantation and Syzygium cumini plantation. Arthropod sampling was done twice using yellow trap. High bird abundance and richness were recorded in edge habitat. A total of 24 bird species of 18 families and 10 orders of arthropod were identified in the study plots. There is no correlation between arthropod and bird abundance. Based on major diet, 46% of bird species were insectivores, while 54% species where other types of eater such as 29% species were frugivores, 9% species were nectarivores, and each 4% of bird species were seabirds, carnivores and scavengers, omnivores, and other bird groups). 
 Key words: arthropod communities, bird communities, fragmentation, Ternate

The effects of agricultural landscape composition and heterogeneity on bird diversity and community structure in the Chengdu Plain, China

Farmland is one of the most important ecosystems in the world, providing foods and habitats for humans as well as many wild animals. However, biodiversity in farmlands has been substantially impacted by the intensification of agriculture and changes in landscape. Increasing either the area of natural and semi-natural habitat or the proportion of biodiversity-friendly crops could potentially mitigate the decline of biodiversity, but at the same time they would affect the agricultural economic output and were not widely applied. To date, some studies have focused on whether crops or cropland heterogeneity has a positive impact on biodiversity, but the results were inconsistent and it is difficult to summarize the relationship between farmland heterogeneity and farmland biodiversity in general. Meanwhile, few papers have studied the differences in bird diversity among small-scale agriculture in China. We conducted a year-long field survey on the Chengdu Plain to explore the relationships of landscape composition and the heterogeneity of cropland and non-cropland with bird diversity and community structure across different seasons. Using generalized linear models (GLM) and generalized least squares (GLS) for data analysis, our results showed that bird diversity is positively correlated with natural woodlands but negatively correlated with commercial forests. Both crop and non-crop landscape compositional heterogeneity affect bird diversity and community structure, especially during the non-breeding season, as many high-altitude birds come down to the farmland for foraging. Both bird diversity and community structure are influenced by cropland configurational heterogeneity, but seldomly influenced by non-cropland configurational heterogeneity. We propose to maintain the area of natural habitat and increase the area of mixed commercial forests by replacing monocultures. Diversified crop and non-crop types with a reasonable layout could conserve farmland biodiversity and maintain the stability of local ecosystems. More research on landscape heterogeneity in small-scale agriculture is needed to provide better understanding of the relationship between the agricultural landscape and bird diversity.

Heterogeneous urban green areas are bird diversity hotspots: insights using continental-scale citizen science data

Urbanization fragments and destroys natural landscapes, generally decreasing bird diversity. While in some cases bird diversity continuously decreases in response to urbanization, in others a non-linear response is evident, with peak bird diversity observed at intermediate levels of urbanization. But many studies previously investigating this pattern are spatially or temporally constrained. In this study, we analyzed the impacts of urbanization on bird diversity, stratified to native and exotic species. We specifically investigated the differences in bird diversity between natural and urban green areas. We used eBird citizen science data (> 4,000,000 bird-survey lists) and remotely-sensed landcover data, throughout the contiguous United States of America. We found a non-linear response to urbanization for both species richness and Shannon diversity. There was distinctly greater bird richness and Shannon diversity in urban green areas compared to natural green areas. Our observed response is likely explained by an increase in habitat heterogeneity of urban green areas compared with natural green areas. Our work highlights the importance of diverse urban green areas for supporting bird diversity in urban areas. We recommend that urban planning should focus on maintaining high habitat heterogeneity in urban green areas to promote greater bird diversity.

Avian Abundance, Diversity and Conservation Status in Etago Sub-County Kisii County Kenya

Bird’s species diversity and abundance are being threatened due to agricultural activities and anthropogenic practices which causes habitat destruction and fragmentation. Understanding how avian species respond to habitat destruction is important towards development of effective measures to ensure that the environment is protected. A study on avian abundance, diversity and conservation status was conducted in Etago Sub-County, Kisii County Kenya from September 2018 to February 2019. Point counts and time species counts were used to carry out birds’ survey to determine their abundance and diversity in the secondary forest, sugarcane plantations, human settlement and mixed firms. A total of 4992 individuals were observed and recorded in the entire study area. The human settlement had the highest density of 1.664 ± 0.18 birds/ha followed by sugarcane plantation with 1.092 ± 0.16 birds/ha and Nyangweta secondary forest was third with 0.0819 ± 0.13. Mixed firms had the least density of 0.95 ± 0.017 bird/ha. Further Dunn’s multiple comparisons test showed that Mixed farming and forest had no significant difference and had mean rank difference of 11.37. In mixed farming vs human settlement there was a significant difference with a mean rank difference of 57.38; in mixed farming vs sugarcane farms there was no significant difference; in the four habitats, 114 species of birds were cumulatively recorded. Out of these, 106 species were recorded in the secondary forests, 98 human settlement and 87 species in the sugarcane plantations and 55 in mixed farms. There was a significant difference in bird diversity in the four habitats where Secondary forest had the highest diversity of 3.85 and sugarcane plantations had a diversity of 3.71 while human settlement and mixed firms had lower diversities of 2.6 and 2.5 respectively (df1 = 2, df2 = 0.0 F = 0.00001, P = 0.00001).

Spatio-Temporal Avian Diversity in the Jambelí Archipelago, Southwestern Ecuador

In the last two decades, more than 35% of coastal wetlands in the tropics and subtropics have been destroyed, mangrove forest being the most affected habitat. However, mangroves have been poorly studied around the world, particularly in the Neotropics. The spatio-temporal diversity of the mangrove bird community in the Jambeli archipelago, in southwestern Ecuador, was studied. Between 2 August 2015 and 25 July 2016, a total of 118 species (35 migratory and 83 resident species) belonging to 44 families were documented. Nine of the 83 resident species are endemic to the coasts of Ecuador and northwestern Peru; six are threatened species. The most abundant species in the archipelago were Magnificent Frigatebird (Fregata magnificens) and Neotropic Cormorant (Phalacrocorax brasilianus), while the best represented family was Laridae (n = 12 species). No spatial or temporal differences in bird diversity were detected (P > 0.35). The Jambeli archipelago has a high diversity of bird species, particularly as a wintering and stopover site for boreal migratory species. A long-term monitoring program for bird populations in the area has been proposed as an effective tool to assess the conservation status of this important and threatened ecosystem.

Adapting the Fire-Grazing Interaction to Small Pastures in a Fragmented Landscape for Grassland Bird Conservation

In North America, the loss of habitat heterogeneity resulting from homogeneous livestock grazing is one factor contributing to steep population declines of many grassland bird species. Patch-burn grazing is a management technique that uses historic grassland disturbance as a model to create heterogeneous grassland composition and structure, providing for the diverse habitat requirements of grassland birds. Though this management technique has been used successfully in relatively extensive grasslands, its utility on smaller grassland patches is less clear. We examined the efficacy of patch-burn grazing to restore habitat heterogeneity and increase grassland bird diversity in relatively small pastures (15–32ha) in a grassland landscape fragmented by cultivation and tree encroachment. In 2006, we established 12 experimental pastures in the Grand River Grasslands of southern Iowa and northern Missouri, with 4 pastures in each of three treatments: 1) patch-burn graze, with spatially discrete fires and free access by cattle (the fire-grazing interaction), 2) graze-and-burn, with free access by cattle and a single burn of the entire pasture every third year, and 3) burn-only, with a single burn of the entire pasture every third year and no grazing. Patch-burn grazing in the first phase of the project (2007–2009) did not generate habitat heterogeneity or significant differences in bird diversity. From 2010 to 2013, stocking rates were reduced to increase residual vegetation in unburned patches at the end of the grazing season to increase heterogeneity. Habitat heterogeneity in patch-burn graze pastures subsequently increased relative to other treatments. Concomitantly, diversity of obligate grassland birds also increased in patch-burn graze pastures and was greatest in 2012 and 2013. We conclude that the fire-grazing interaction can be used to restore habitat heterogeneity and increase grassland bird diversity, even in relatively small grassland patches embedded in a highly fragmented landscape.

An avifaunal survey of mesic manmade ecosystems “Oases” in algerian hot-hyperarid lands

Man made ecosystems of dry lands are key habitats due to their ecological characteristics to survey biodiversity. This study investigated bird diversity in three oases of the Northern Algerian Sahara (i.e., Biskra in 2006, Oued Souf in 2008 and Ouargla in 2009), by using the spot-mapping method. Bird density “D” (pairs/10ha), species richness “S” (number species), diversity (Shannon index) “H′” (in bits), and evenness “E” varied from one oasis to another (Biskra: D=98.5, S=47, H′=4.49, E=0.81; Oued Souf: D=96, S=33, H′=3.9, E=0.77; Ouargla: D=91.5, S=44, H′=4.39, E=0.80). Differences in bird diversity between the monitored palm groves are due to the ecological characteristics of each environment. Documented literature outlined close taxonomic similarities between bird assemblages of the study area with many Northern Saharan oases. The Hybrid Sparrow Passer domesticus x Passer. hispaniolensis and some Columbidae species including Columba livia, Streptopelia turtur, Streptopelia senegalensis, and Streptopelia decaocto were the abundant species throughout surveyed oases in which they represented more than half (55.6%) of the sum of species densities (D=286 pairs/10ha). These synthropic species have known a huge expansion of their distribution range throughout Algerian oases. The correspondence analysis allowed the aggregation of both families and species into oasis they belong to. One-way ANOVA was tested to analyse variations of both family and species densities between studied oases. The ANOVA revealed there was no significant variation either in family densities (p=0.937) or in bird densities (p=0.622) between the surveyed oases because of the small size of bird populations.

Effect of stand age on bird communities in late-successional Macedonian pine forests in Bulgaria

To gain insight into the question of which vegetation characteristics have the most influence on avian assemblages in late-successional forests, the habitat preferences of bird-guilds in old-growth endemic forests of Macedonian pine were studied over 3 years in the Pirin National Park, Bulgaria. Bird–habitat relationships were investigated by comparing vegetation characteristics, and bird species richness, diversity, abundance, and guild structure of birds (determined according to food type, foraging and nesting sites) between mature (60–100 years old) and over-mature (>120 years old) Macedonian pine forest stands. Studied forest age-classes differed mainly by the density, height and diameter of trees, and the amount of dead wood. The first one of these parameters decreased and the latter two parameters increased with the forest succession. The difference in the vegetation structure affected the abundance of bird-guilds and thus, the overall bird abundance and the structure of avian assemblages within Macedonian pine forests. There was no significant difference in bird diversity among studied forest age-classes, but the overall bird abundance increased with forest maturation. Analyzed by study plots, species richness was higher in over-mature forests, but at cluster level, there was no significant difference between mature and over-mature forest age-classes. Half of the studied (insectivorous, hole- and ground-nesters, bark- and canopy-foraging bird species) guilds were more abundant in over-mature forests, while there was no bird-guild exhibiting a preference for mature forest stands. The abundances of bird-guilds were correlated with tree height, diameter at breast height and the amount of dead wood between the studied forest age-classes and this might explain their preferences for over-mature pine forests. Therefore, for future sustainable management of these endemic forests and the conservation of their avifauna, efforts should focus on protecting the remaining native old-growth forest stands and the importance of the structure of Macedonian pine forests on their bird assemblages should be considered in forestry practices.

Effects of dog leash laws and habitat type on avian and small mammal communities in urban parks

Remnant natural areas within urban settings can act as important refuges for wildlife, substantially increasing local biodiversity. However, habitat suitability for these species is potentially affected by human recreational activities including the presence of free-running dogs. To compare the diversity and abundance of songbird and small mammal communities between areas with bylaws that require, or do not require, dogs to be leashed, point counts and live-trapping surveys were conducted in three habitat types (deciduous, coniferous, and meadow) in the river valley parks of Edmonton, Alberta. Among birds, there was no difference between areas with different leashing bylaws in species diversity for any of the three habitat types. Similarly, there was no difference in bird diversity for a subset of species that were plausibly breeding at these sites. However, higher bird diversity was recorded in deciduous and coniferous sites than in meadow sites, regardless of leash designation, probably as a function of the horticultural practice of mowing meadows. Among both birds and small mammals, there was no difference in the abundance of individuals as a function of leashing bylaws. Our results suggest that off-leash dogs have no effect on the diversity or abundance of birds and small mammals in urban parks, but it is also possible that other factors, such as leash law compliance, reduced or obscured the effects of off-leash dogs in this study.

Decline of landscape-scale habitat and species diversity after the end of cattle grazing

A decrease of habitat and species diversity in agricultural landscapes, mainly as a result of the decline of semi-natural grasslands, has been shown in several studies. However, no studies have linked the effects of decrease of grassland management with landscape structure and plant and bird species diversity on the landscape scale in a spatial grid system. In this study we examined the differences in the present habitat and species diversity (number of total and rare plant and bird species) among agricultural landscapes differing in their management history. We compared areas of 0.25 km 2 (n = 34) with different grazing history in the Rekijoki river valley, SW Finland. The grazed area decreased to one fifth over 30 years (1960–1990) in our study area. The earlier interconnected network of grazed patches was disrupted, resulting in an isolated grazing pattern. There were statistical differences in the habitat structure and plant species diversity between the landscapes with different management histories, but no difference in bird diversity was observed. The number of rare plant species/0.25 km 2 was 45% less in areas of 20–40 years of abandonment compared to squares with continuously grazed patches. The results address the importance of grazing management for maintaining heterogeneous habitat mosaics and plant diversity on the landscape scale.

Differences in bird diversity between two swidden agricultural sites in mountainous terrain, Xishuangbanna, Yunnan, China

This study took a comparative look at the relationship between human-altered landscapes and bird diversity in two mountainous swidden (slash and burn) agricultural sites in Xishuangbanna, Yunnan, China. Over the course of 3 years (1998–2000) the authors used line-transect identification surveys in the two regions, Mengsong and Jinuo, where four different habitats were surveyed: 6-year fallow fields; traditional economic forests; monsoon evergreen broadleaf forests; and montane rain forests. Data were analyzed for species diversity, richness (family, genera, species), co-occurrence (family, genera, species), characterization of migratory status and feeding habits. Both of these study areas are inhabited by minority groups (Hani and Jinuo) that employ swidden agriculture as their main form of economic activity. The forest landscape in the Jinuo ethnic region is quickly transforming due to changing agricultural practices, and as a result bird diversity and richness are declining, while the Hani ethnic region (Mengsong), with a stable form of traditional swidden agriculture, is maintaining a high diversity and richness of birds. The greatest differences in bird diversity between the two sites occurred in the traditional economic forests and the 6-year fallow fields where the Hani region had a much greater richness and diversity. The two natural forest types (monsoon evergreen broadleaf forests and montane rain forests) were more similar in richness and diversity and also maintained the greatest richness and diversity of the four forest types analyzed. The transformation of healthy forests into degraded landscapes is one of the major impacts of human activity on the natural environment, which is posing a great threat to biodiversity. This study looks at the bird diversity of the two regions and tries to take into account how humans can extract economic benefits while preserving ecological benefits, such as a landscape that allows biodiversity to thrive.