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High-elevation species are expected to be vulnerable to climate warming and to experience dramatic range contractions in the coming decades. Indeed, climate change in high-altitude biota has proceeded at a faster pace compared to lowlands. Understanding basic ecological features of mountain species, such as their foraging ecology, may be useful to further our understanding of the mechanisms dictating species distributions and their responses to global warming, ultimately improving conservation strategies. In this study, we investigated foraging habitat selection of the poorly studied Alpine White-Winged Snowfinch Montifringilla nivalis during the nestling rearing period (June-July) in the Italian Alps. Pair members from 18 different nests were visually followed for 1 day or until we obtained 10 foraging locations. At foraging and control plots (equal numbers per breeding pair; control plots within 300 m of the nest, the average exploited radius according to literature) we recorded habitat variables (habitat types/heterogeneity, sward height, slope, solar radiation). We built models of foraging habitat selection and evaluated whether the selection of climate-related variables varied with temperature and season progression. Snowfinches preferred to forage at colder (low solar radiation) sites, with snow patches and short grasses, some boulders and bare ground, and shifted towards sites with increasingly lower solar radiation after the first week of July. Snow patches are likely to provide both arthropod fallout and suitable sites for invertebrates at their melting margins. Short herbaceous layers likely improved invertebrate detectability in addition to their abundance. These results suggested that climate change may impact on the foraging ecology of this species: warming may reduce the availability of snow patches and favor a denser and taller sward, and may reduce the time frame within which melting snow patches are highly profitable. Hence, the fine-scale habitat requirements of foraging Snowfinches highlight the species' potential high sensitivity to anthropogenic climate warming. [ABSTRACT FROM AUTHOR]

• We surveyed breeding birds and measured forest structure for 5 years after mixed-severity wildfires in upland hardwood forests. • Tree mortality and shrub recovery were greatest and increased over time in high-severity burn patches. • Bird abundance, richness, and diversity were greatest in high- and moderate-severity burn patches. • Abundance of disturbance-dependent and several other bird species increased over time in high-severity burn patches. • Changes to forest structure and avian communities were negligible in low-severity burn patches. • We suggest that heavy canopy reduction and increased bird diversity can be attained by high-severity fire or silvicultural methods. In 2016, mixed-severity wildfires in the southern Appalachians created a gradient of forest structures not typical following prescribed burns, providing a unique opportunity to study temporally dynamic conditions and breeding bird response. We measured forest structure and breeding bird communities across a fire-severity gradient in 3 burned and 3 unburned watersheds for 5 years (Y1-Y5). We categorized plots as unburned (NB), low- (L), moderate- (M), or high-severity (H) using a composite fire-severity index. Tree mortality increased with fire-severity category (FSC) and over time; by Y5, 7 % of trees in NB, 11 % in L, 38 % in M, and 71 % in H had died. Shrub recovery was rapid and most pronounced in H, exceeding other FSCs (70 % vs 21 %–44 %) by Y5. Total bird abundance, species richness, and diversity increased over time in H (by Y3) and M (by Y4); by Y5, these metrics were highest in H and twice as high in H as in NB. Low-severity wildfires had no detectable effects on birds. Abundance of 7 species was greatest in higher-severity FSCs; 11 species did not differ among FSC, although ovenbirds (Seiurus aurocapilla) indicated a trend of lower abundance in H. No species was limited to NB, L, or M, whereas disturbance-dependent indigo bunting (Passerina cyanea), chestnut-sided warbler (Setophaga pensylvanica), and eastern towhee (Pipilo erythrophthalmus) were primarily associated with H. Increased richness and diversity were associated with heavy tree mortality and subsequent shrub recovery in H, accompanied by an influx of disturbance-dependent species and positive or neutral responses by most other species. Results highlight the interrelated roles of fire severity and time in driving forest structure and breeding bird response. Breeding birds responded to high-severity burns similarly to silvicultural treatments with heavy canopy reduction documented in other studies, offering possible alternatives when managing for breeding bird diversity in hardwood forests. [ABSTRACT FROM AUTHOR]

Agricultural landscapes have crucial functions for biodiversity conservation. Contrary to the goals of biodiversity protection the habitat functions and the biological diversity are deteriorating, especially in arable areas. In this respect, the occurrence and abundance of bird species are important indicators for biological diversity and landscape quality. In order to gain precise information about the preferred habitats for indicator bird species in arable areas, we conducted field studies according to the territory mapping method combined with data of the agricultural land use. We studied 29 agricultural areas, each with a size of 1 km x 1 km in 2009 and 2010. In a hierarchical design we analyzed habitat characteristics on different spatial scales: agricultural landscape, sections of agricultural landscape, habitats, including crops, vegetation structure, and habitat matrix. The species diversity and the abundances were calculated for the various spatial scales in relation to the agricultural crops. For example, the abundances of the skylark pointed to a preference for a more open, light vegetation structure (height, coverage, density) of the crops. With help of vegetation matrix analysis the habitat configurations of the territories for skylark, corn bunting, yellowhammer, yellow wagtail, whinchat and redbacked shrike were analyzed. In comparison of this configurations to the habitat structures in the agricultural landscape, significant deficits of suitable habitats for farmland bird are evident. Especially, a need for natural and semi-natural grassland vegetation, e.g. self greened fallow fields and bird species specific minimum occurrence of semi-natural habitat structures like hedges or small water bodys become clear. A high diversity of crops contributes to high diversity of vegetational diversity and thus to bird species diversity. The identification of suitable habitat configurations for farmland bird species can be translated into meaningful approaches for the conservation of biodiversity, e.g. through agri-environmental schemes.

Numbers of breeding pairs of breeding birds and breeding density are established by territory mapping in Limanski (12.9 ha), Futoški (8.26 ha), and Dunavski (3.9 ha) Parks in Novi Sad from early March to late June 2007. In Limanski Park 11 species of breeders were found, the most numerous being tree sparrow (Passer montanus). Futoški Park had 15 breeders and the most numerous were great tit (Parus major). The smallest number of species (9) bred in Dunavski Park, with great tit as the most common breeder. The greatest density of breeding pairs was recorded in the largest park (37.7 pairs/km2). Hole-breeders dominated in Futoški and Dunavski Park, but their number was the same as the number of canopy-breeders in Limanski Park. Measured with Sorensen index of similarity, the greatest similarity was found between breeding avifauna of Futoški and Dunavski Park (72), then between Futoški and Limanski (61), while the smallest similarity was found if we compare breeding avifauna of Dunavski and Limanski Park. Compared with breeding avifauna in other parks in Central Europe, breeding avifauna of Novi Sad parks is relatively poor.

ABSTRACT The Conservation Reserve Program (CRP) is a voluntary program that is available to agricultural producers to help protect environmentally sensitive or highly erodible land. Management disturbances of CRP grasslands generally are not allowed unless authorized to provide relief to livestock producers during severe drought or a similar natural disaster (i.e., emergency haying and grazing) or to improve the quality and performance of the CRP cover (i.e., managed haying and grazing). Although CRP grasslands may not be hayed or grazed during the primary bird-nesting season, these disturbances may have short-term (1 yr after disturbance) and long-term (≥2 yr after disturbance) effects on grassland bird populations. We assessed the effects of haying on 20 grassland bird species in 483 CRP grasslands in 9 counties of 4 states in the northern Great Plains, USA between 1993 and 2008. We compared breeding bird densities (as determined by total-area counts) in idle and hayed fields to evaluate changes 1, 2, 3, and 4 years after haying. Haying of CRP grasslands had either positive or negative effects on grassland birds, depending on the species, the county, and the number of years after the initial disturbance. Some species (e.g., horned lark [ Eremophila alpestris], bobolink [ Dolichonyx oryzivorus]) responded positively after haying, and others (e.g., song sparrow [ Melospiza melodia]) responded negatively. The responses of some species changed direction as the fields recovered from haying. For example, densities for common yellowthroat ( Geothlypis trichas), sedge wren ( Cistothorus platensis), and clay-colored sparrow ( Spizella pallida) declined the first year after haying but increased in the subsequent 3 years. Ten species showed treatment × county interactions, indicating that the effects of haying varied geographically. This long-term evaluation on the effects of haying on breeding birds provides important information on the strength and direction of changes in bird populations following a disturbance. Results from this study can help guide management of CRP and other grasslands and inform future agricultural programs that address biomass energy production. © 2016 This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

The Mediterranean basin is considered one of the most important biodiversity hotspots. This extraordinary richness originates mainly from thousands of years of human activities that deeply modified the landscape. Safeguarding the so-called cultural landscapes plays a key role in biodiversity conservation. In this paper we present the results of our monitoring of the effects of the life project 'Preservation of mountain grasslands of the Tuscan Apennines', mainly characterized by shrub-cutting actions, on bird populations in the Pratomagno pasture, one of the two areas where the project was implemented, a SPA in eastern Tuscany. The monitoring plan covers a period of 5 years. We tested the effects of shrub clearing on a series of bird community parameters, such as abundance and richness of common species and of some ecological guilds. We also tested the timing of the response to the interventions (immediate or drawn out over time). Our results show a dramatic decrease of birds associated with shrubland, while there were no important increases in grassland species, with the sole exception of Woodlark. Regardless of their positive or negative effects, our results show different response times for individual species or groups of species. Moreover, species with a bad regional conservation status increased less than those with a good one. Broadly speaking, these results suggest that the efficacy of such projects depends on a careful preliminary assessment of a number of aspects, encompassing the nature of the interventions themselves and the characteristics of the target sites, but also the type of response of target species and the conservation status of target populations. [ABSTRACT FROM AUTHOR]

Climate change is causing widespread geographical range shifts, which likely reflects different processes at leading and trailing range margins. Progressive warming is thought to relax thermal barriers at poleward range margins, enabling colonization of novel areas, but imposes increasingly unsuitable thermal conditions at equatorward margins, leading to range losses from those areas. Few tests of this process during recent climate change have been possible, but understanding determinants of species' range limits will improve predictions of their geographical responses to climate change and variation in extinction risk. Here, we examine the relationship between poleward and equatorward range margin dynamics with respect to temperature-related geographical limits observed for 34 breeding passerine species in North America between 1984-1988 and 2002-2006. We find that species' equatorward range margins were closer to their upper realized thermal niche limits and proximity to those limits predicts equatorward population extinction risk through time. Conversely, the difference between breeding bird species' poleward range margin temperatures and the coolest temperatures they tolerate elsewhere in their ranges was substantial and remained consistent through time: range expansion at species' poleward range margins is unlikely to directly reflect lowered thermal barriers to colonization. The process of range expansion may reflect more complex factors operating across broader areas of species' ranges. The latitudinal extent of breeding bird ranges is decreasing through time. Disparate responses observed at poleward versus equatorward margins arise due to differences in range margin placement within the realized thermal niche and suggest that climate-induced geographical shift at equatorward range limits more strongly reflect abiotic conditions than at their poleward range limits. This further suggests that observed geographic responses to date may fail to demonstrate the true cost of climate change on the poleward portion of species' distributions. Poleward range margins for North American breeding passerines are not presently in equilibrium with realized thermal limits. [ABSTRACT FROM AUTHOR]

Grazing and browsing by sheep and goats has been an important anthropogenic influence on ecosystems in the Mediterranean region for centuries. This influence has changed significantly in recent decades, with a general shift from range grazing to the penning of animals. The intermediate disturbance hypothesis (IDH) proposes that perturbation - including anthropogenic disturbance - is the norm for Mediterranean ecosystems, and that higher species diversity is found under conditions of continuous, moderate disturbance. Here we test the IDH as it relates to grazing of scrub and open forest habitats in Cyprus, while also testing for the effects of fire. We carried out surveys of breeding birds and vegetation at 48 study sites in scrub and open woodland across Cyprus. We estimated relative grazing pressure (past and present) and fire history at these sites, and tested for associations between these factors, breeding bird species richness and perennial vegetation diversity. We found moderate current grazing reduces density of lower and middle level scrub, and a higher level of diversity of perennial vegetation at moderately over intensively grazed sites. We found that moderate historical grazing pressure had a positive influence on richness of breeding bird species in lower scrub habitat such as phrygana, but that this effect was weaker the taller and denser the habitat. By contrast, current grazing pressure had a negative effect on species richness in lower scrub, but species richness in grazed habitats was higher in denser, taller scrub habitat such as garrigue and maquis. Our study suggests grazing plays an important role in maintaining habitat heterogeneity but the impact on avian species richness depends on the density and height of the vegetation. [ABSTRACT FROM AUTHOR]

Birds that reside in urban settings face numerous human-related threats to survival, including mortality from bird-window collisions (BWCs). Our current understanding of this issue has largely been driven by data collected during spring and fall migration, and patterns of collision mortality during the summer breeding season remain relatively unexplored. We assessed BWCs during four breeding seasons (2009–2012) at a site in northwestern Illinois, USA, by comparing the abundance, richness, migratory class, and age of the species living around buildings to species mortally wounded by window collisions. We also systematically assessed the daily timing of BWCs throughout the breeding season. We documented BWCs in 4 of 25 (16%) species and 7 of 21 (33%) species in 2009 and 2010, respectively. The relationship between BWCs and abundance depended on age. For adults, BWCs were highest in the least abundant species, e.g., Red-eyed Vireo (Vireo olivaceus), and lowest in species with high abundance values, e.g., Chipping Sparrow (Spizella passerina). For juveniles, mortality was greatest for the most abundant species, and the American Robin (Turdus migratorius) accounted for 62% of all juvenile carcasses. Early in the breeding season, collision mortality was restricted to adults of Long-distance Migrants, whereas juveniles of all three migratory guilds (Long-distance and Short-distance Migrants and Permanent Residents) died at windows from late June through early August. Daily mortality for all species was highest between sunrise–1600 h and lowest from 1600 h–sunrise the next day. Generally, the species observed as carcasses matched birds considered a ‘high risk’ for BWCs, e.g., Ruby-throated Hummingbird (Archilochus colubris), and those considered ‘low risk’ were not observed as carcasses, e.g., Blue-gray Gnatcatcher (Polioptila caerulea). Our results suggest that the number of BWCs during the breeding season does not necessarily increase with abundance, but rather appears related to variation among species and age classes, which may have important implications on the population health of affected species. The mechanisms driving these differences are unknown, but may be related reproductive behavior, flight speed, distance movements, and dispersal patterns.

Animal populations are currently under pressure from multiple factors that include human land use and climate change. They may compensate for such effects by reducing, either by habituation or by natural selection, the distance at which they flee from humans (i.e., flight initiation distance), and this adaptation may improve their population trends. We analyzed population trends of common breeding birds in relation to flight initiation distance and geographical location (latitude, longitude, and marginality of the breeding distribution) across European countries from Finland in the north to Spain in the south while also considering other potential predictors of trends like farmland habitat, migration, body size, and brain size. We found evidence of farmland, migratory, and smaller-sized species showing stronger population declines. In contrast, there was no significant effect of relative brain size on population trends. We did not find evidence for main effects of flight initiation distance and geographical location on trends after accounting for confounding and interactive effects; instead, flight initiation distance and location interacted to generate complex spatial patterns of population trends. Trends were more positive for fearful populations northward, westward, and (marginally) toward the center of distribution areas and more negative for fearless populations toward the south, east, and the margins of distribution ranges. These findings suggest that it is important to consider differences in population trends among countries, but also interaction effects among factors, because such interactions can enhance or compensate for negative effects of other factors on population trends. [ABSTRACT FROM AUTHOR]

It is crucial to define and quantify possible impacts of climate change on wildlife in order to be able to pre-adapt management strategies for nature conservation. Thus, it is necessary to assess which species might be affected by climatic changes, especially at the regional scale. We present a novel approach to estimate possible climate change induced turnovers in bird communities and apply this method to Lüneburg Heath, a region in northern Germany. By comparing species pools of future climatically analogous regions situated in France with the Lüneburg Heath species pool, we detected possible trends for alterations within the regional bird community in the course of climate change. These analyses showed that the majority of bird species in Lüneburg Heath will probably be able to tolerate the projected future climate conditions, but that bird species richness, in general, may decline. Species that might leave the community were often significantly associated with inland wetland habitats, but the proportion of inland wetlands within the regions had a significant influence on the magnitude of this effect. Our results suggest that conservation efforts in wetlands have to be strengthened in light of climate change because many species are, in principle, able to tolerate future climate conditions if sufficient habitat is available. [ABSTRACT FROM AUTHOR]

ABSTRACT Long-term landscape-scale experiments allow for the detection of effects of silviculture on bird abundance. Manipulative studies allow for strong inference on effects and confirmation of patterns from observational studies. We estimated bird-territory density within forest stands (2.89-62 ha) for 19 years of the Missouri Ozark Forest Ecosystem Project (MOFEP), a 100-year experiment designed to study the effects of even-age and uneven-age management on wildlife. We spot-mapped territories of 15 species in 228 stands for 5 years before treatment and 14 years after treatment to assess the effects of stand-level silvicultural treatments (clearcut, select cut, thin, and no-harvest) applied within even-age, uneven-age, or no-harvest (control) management sites and year on avian territory density. We used 2 a priori contrasts to compare pre-treatment bird densities with densities during early (3-5 yr) and late (12-14 yr) post-treatment periods. The interaction of silvicultural treatment and year had significant effects on the densities of all 15 species. Densities of hooded warbler ( Setophaga citrina), indigo bunting ( Passerina cyanea), prairie warbler ( Setophaga discolor), and yellow-breasted chat ( Icteria virens) increased significantly 3-5 years post-treatment with the greatest changes in clearcuts, but densities 12-14 years post-treatment did not differ from pre-treatment densities. Densities of Acadian flycatcher ( Empidonax virescens), wood thrush ( Hylocichla mustelina), and especially ovenbird ( Seiurus aurocapilla) had significant decreases in clearcut stands after treatment and lesser decreases in select cut or thin stands post-treatment. Densities of black-and-white warbler ( Mniotilta varia), eastern wood-pewee ( Contopus virens), and Kentucky warbler ( Geothlypis formosa) increased in clearcut, thin, and select cut stands, but these increases were short-lived and sporadic by year after treatment. Densities of Acadian flycatcher and ovenbird remained lower in clearcut stands than no-harvest stands 13 years post-treatment. The results of this manipulative experiment were mostly consistent with our predictions of bird response to common silvicultural treatments in these forests. Managers can use these species-specific responses to silvicultural treatment to guide management decisions for target species or to balance management practices in a landscape to meet the needs of multiple species. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Himalayan forests are undergoing rapid changes due to population growth and economic development and their associated bird communities are among the most threatened and least-studied on earth. In the Chinese Himalaya, traditionally managed Tibetan sacred forests are keystone structures for forest bird conservation. Yet, it remains unclear which fine-scale habitat characteristics of the sacred forests are best associated with Himalayan forest bird species. Our goal here was to quantify the relationship between forest habitat characteristics and bird communities in Tibetan sacred forests to understand habitat associations of common forest birds in the Chinese Himalaya. In 2010 and 2011, we conducted bird point counts and habitat surveys at 62, 50-m radius, sample points distributed within and adjacent to six Tibetan sacred forests in northwest Yunnan, China. From this data, we constructed habitat-occupancy relationship models for 35 bird species and documented tree-use patterns of 14 common arboreal foraging bird species. Our modeling results revealed that large diameter trees and heterogeneity in vertical vegetation structure were the most important habitat characteristics, and were positively associated with occupancy of 63 % of the study bird species. Furthermore, we found that occupancy of eight bird species of conservation concern was related to specific thresholds of forest integrity characteristics. For example, predicted occupancy of three of eight species was high in forested habitats with >15 % bamboo cover and was greatly reduced when bare ground cover exceeded 5 %. We found that bird species foraged on pine ( Pinus densata, 58 % more than it was available) and poplar ( Populus davidiana, 41 %) in higher proportion to their availability, but that foraging success was highest on fir ( Abies spp.), oak ( Quercus spp.), willow ( Salix spp.) and Chinese Larch ( Larix potaninii). Our findings suggest that, although conservation is not a primary management goal of Tibetan sacred forests, these lands harbor critical habitat features for forest breeding birds of the Chinese Himalaya. [ABSTRACT FROM AUTHOR]

The aim of the study done in 2011 and 2012 was to identify the number of breeding bird species, to provide population estimates as well as to evaluate the conservational importance of Škocjan Caves Park for birds. Common bird species were surveyed using the territory mapping method. Rare species and nocturnally active species were surveyed using species-specific methods: observation, the playback method and the line transect method. 81 species were registered, 49 of which bred within the boundaries of the Park. The most abundant breeding species were Blackcap Sylvia atricapilla (260-320 breeding pairs), Robin Erithacus rubecula (250-310 breeding pairs), Blackbird Turdus merula (230-280 breeding pairs), Chaffinch Fringilla coelebs (230-280 breeding pairs) and Marsh Tit Poecile palustris (200-240 breeding pairs). Qualifying species for the Special Protected Area (SPA) Kras (SI5000023) also bred within the Park: Peregrine Falcon Falco peregrinus, Nightjar Caprimulgus europaeus, Scops Owl Otus scops and Woodlark Lululla arborea. Eagle Owl Bubo bubo was also registered, but breeding attempts during the study period were unsuccessful due to the negative influence of several factors. One of the largest colonies of Alpine Swifts Apus melba, a rare and localized species in Slovenia, is also of conservation concern. [ABSTRACT FROM AUTHOR]

ABSTRACT Nonnative plant invasions are a management concern, particularly in riparian forests, but little is known about mechanisms through which they influence vertebrate communities. In the American Southwest, native trees such as cottonwood ( Populus spp.) are thought to provide better habitat for breeding birds than nonnative plants, which are more tolerant of human-altered conditions. To evaluate effects of riparian forest composition on riparian-nesting birds, we examined nest plant use along two rivers in New Mexico that differed in abundance of nonnative vegetation. Of the nests we observed, 49% along the Middle Rio Grande were constructed in nonnative plants, compared with 4% along the Gila River. Birds in the canopy and cavity-nesting guilds constructed less than 5% of their nests in nonnative plants along either river. At the Middle Rio Grande, birds in the subcanopy/shrub guild constructed 67% of their nests in nonnative plants. Despite the relatively low availability of cottonwoods, they were used by greater numbers of species than any other woody plant at either river. Riparian obligates and species of conservation concern in the canopy and cavity guilds were especially dependent on cottonwood and Arizona sycamore ( Platanus wrightii). Our results show that, although nonnative trees and shrubs support large numbers of nests for certain birds, cottonwoods and other large native trees are disproportionately important to riparian bird communities. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In a survey of land and water birds of Tukarak and Nastapoka Islands and Lac Guillaume-Delisle in summer 2011, we recorded 22 of the 30 species known to breed on the Belcher Islands, as well as five non-breeding species, and we observed 32 species in Lac Guillaume-Delisle. In all areas surveyed, we observed a total of 43 species: 10 waterfowl, 2 gallinaceous birds, 3 loons, 2 hawks, 3 shorebirds, 1 auk, 3 gulls, 2 falcons, and 17 songbirds. In this area of Hudson Bay, a number of species reach the southern or northern limit of their breeding distribution in eastern Canada. In light of the impact that climate change may have on bird distribution in northerly latitudes, the Belcher Islands and adjacent mainland areas could be particularly useful locations for monitoring changes in the breeding range of birds. [ABSTRACT FROM AUTHOR]

Population declines of several successional-scrub bird species are partly associated with decreased habitat availability as abandoned farmlands return to forest and recently harvested forests regrow. Restoration of mixed-oak ( Quercus spp.) forest is also a concern because of widespread oak regeneration failure, especially on moist, productive sites where competition from faster-growing tree species is fierce following stand-replacing disturbances. Several silvicultural methods are proposed to promote oak regeneration but many are not experimentally tested, especially on productive sites. We surveyed birds in 19 stands to assess response to initial application of three proposed oak regeneration treatments on productive sites: prescribed burning (B); oak shelterwood by midstory herbicide (OSW); shelterwood harvests (SW); and controls (C), for one breeding season before, and two breeding seasons after, implementation. Relative density of successional-scrub species Indigo Buntings ( Passerina cyanea), Eastern Towhees (Pipilo erythrophthalmus), and Chestnut-sided Warblers (Setophaga pensylvanica) increased, while Ovenbirds (Seiurus aurocapilla) decreased within 11 to 18 months after SW harvests; understory disturbance treatments B or OSW had no effect. Our results indicated that partial harvests created habitat for breeding birds associated with both young and mature forests, whereas understory treatments had little effect. Additionally, we show that even small patches of young forest habitat are used by more individuals and more species of breeding birds than surrounding closed-canopy forest, and may benefit successional-scrub species by enabling their occurrence in an otherwise forested landscape. Absence of several lower-elevation successional-scrub bird species in our mid-elevation SW harvests suggests that comprehensive conservation in the southern Appalachians necessitates creating and maintaining young forest habitats across elevation gradients. [ABSTRACT FROM AUTHOR]

In a Mediterranean patchy wetland of central Italy, we analyzed the relationship between the number of bird species, expressed in terms of bird alpha diversity, and plant alpha diversity, expressed as Hill number. This number (the exponential of the Shannon entropy) is considered one of the most strong and reliable indexes of alpha-diversity, synthesizing the information on evenness, richness and diversity in one single metric. We observed a progressive increase of the mean values of bird alpha diversity when plant alpha diversity increases along Hill number. Bird alpha diversity shows an abrupt increase between the first and the second of four categories of plant alpha diversity (0-1, >1-2, >2-3, >3), indicating a threshold response in all the groups considered (breeding, wintering and total bird assemblages). This marked decline of bird species richness at around 1 in the Hill index should represent an alarm for managers: wetland sites at or below this level of plant alpha diversity are likely to be experiencing a drastic decrease in bird species richness, both in spring (breeding birds) and in winter (wintering birds). [ABSTRACT FROM AUTHOR]

Aim Climate warming and land use change represent a major challenge for both species and conservation managers. Temporally and spatially explicit projections of the future distribution of species have been extensively developed to support decision-making in conservation. The aim of this study was to move beyond the simple projections of likely impacts of global change to identify the most vulnerable species. We suggest an original vulnerability index that integrates estimations of projected range change and different proxies of species resilience in a quantitative way. The proposed index is generally applicable, completely quantitative, and it allows ranking species so as to prioritize conservation actions. Location We illustrate the applicability of the vulnerability index using breeding birds in Switzerland as an example of conservation target. Methods The vulnerability index relies on five indicators quantifying different aspects of the projected change in distributional area, the reservoirs available for the species and their recent population trend. Species distribution was modelled using three different techniques (GAM, MARS and BRT) and then projected for 2050 and 2100 according to two different IPCC scenarios of climate change coupled with two regional land use scenarios to represent different magnitudes of the stressors and the range of possible outcomes. Results According to the different contributions of the base indicators, different patterns of vulnerability can be distinguished. In Switzerland, breeding birds inhabiting coniferous woodlands, alpine habitats and wetlands have significantly higher vulnerability to climate and land use change than species in other habitats. Main conclusions The proposed vulnerability index represents an early warning system as it identifies species that are currently not threatened, but are very likely to become so. As such, it complements the assessment of risk of species' extinction based on the Red List and on their international importance. [ABSTRACT FROM AUTHOR]

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Highlights: [•] Distance from forest edge shaped bird community composition in deciduous forest. [•] There was a positive edge effect on tree and shrub, but not ground breeding birds. [•] Nest predation rate was higher in tree-species rich than in beech-dominated stands. [•] Large forest area can mitigate potential negative edge effect on nest survival. [Copyright &y& Elsevier]

Hemeroby is a concept widely employed in assessment of the effect of human activities on vegetation. In this study, we apply the concept to a set of bird species occurring in a Mediterranean remnant wetland. The aim was to obtain an average hemeroby index for two seasonally related bird assemblages (i.e. breeding and wintering) based on the information related to two levels of plant hemeroby. In a grid of 47 cells 100×100 m-wide, we sampled the fine-grained distribution of plant communities (Braun-Blanquet method/cell) in parallel with birds (point count method; one point count/cell), assigning an independent score of hemeroby to plants and birds on a scale from I to V, from pristine habitats with a lack of natural and/or anthropogenic disturbance (score = I) to completely artificial habitats (score = V). Whereas bird species ranged from categories II to V, vegetation types spanned only the categories III and IV. Therefore, bird species showed a higher variability in hemeroby. By comparing hemeroby scores, we can deduce the effect that the vegetation disturbance may have on bird species. The mean hemeroby for breeding birds, calculated on all the species occurring in a determined plant hemeroby category, is not significantly different between sites with higher (= IV) and lower (= III) plant hemeroby (i.e. higher and lower level of disturbance). The mean hemeroby of the wintering birds was significantly different in the two levels of plant hemeroby (i.e. higher vs. lower hemeroby). Our data suggest that only the wintering birds had a hemeroby distribution pattern related to that of the plants, while the distribution of breeding birds showed no association, i.e. they appear in similar distribution in both plant hemeroby classes. This pattern may reflect the characteristics of the habitat types in relation to bird seasonality: a large section of wintering bird species are strictly water-related, linked to habitats with low plant hemeroby, so appearing more sensitive to change in plant hemeroby when compared to breeding species. Although explorative, our data may be useful in wildlife management, implying that in wetland–grassland mosaics the more sensitive wintering bird species are suitable as indicators aimed to test the effect of natural and anthropogenic disturbances. [ABSTRACT FROM PUBLISHER]

Highlights: [•] High-severity burns in upland hardwood forest creates early successional conditions. [•] Bird richness and abundance higher in high-severity burns in upland hardwood forest. [•] Repeated low-intensity prescribed burning causes delayed tree mortality. [•] Breeding bird species richness may increase with repeated burning that kills trees. [Copyright &y& Elsevier]

While studies of how habitat patch dynamics structures avian communities in urban environments has received some attention, there is considerably less known of how the built environment and human population size may influence the structuring of urban bird communities. We investigated bird populations in Pittsburgh, Pennsylvania (U.S.A.) through replicated point count surveys of breeding birds in 50 parks and cemeteries of varying sizes. We counted 4,435 individual birds in 441 counts. Of the 61 species detected, 27 were rare (detected at <8 points). Migratory species accounted for 46.1 % of all individuals, while 23.2 % of all individuals were of introduced species. Species richness increased significantly with green area size, as did the number of rare species. Species diversity decreased significantly with an increase in the proportion of individuals of introduced species; in particular, cavity nesters were less abundant when introduced species were present. Elements of the built urban environment including commercial development and transportation corridors were associated with significant reductions in park-wide species richness, mean number of species per point, and mean number of individual birds recorded per point. Human population size was positively related to increased numbers of individuals of introduced species, but a lower mean number of species per point. Ours is among the first to identify specific relationships between avian population characteristics and human population size, as few other studies have specifically incorporated human population size into a local, fine grain study design. Our data suggest that human population size is an important parameter that can be measured independently of characteristics of the built environment and the physical characteristics of the park itself as a correlate of avian diversity and abundance. Our study points to a variety of trade-offs needed to manage habitat for birds in urban settings. [ABSTRACT FROM AUTHOR]

The Illinois State Wildlife Action Plan targeted the Conservation Reserve Program (CRP) as important improvable acres for grassland and grassland-successional bird species of greatest need for conservation. A large portion of CRP grasslands in Illinois and elsewhere lack floristic and structural diversity because of the absence of management and the extensive planting of monotypic grasses such as tall fescue ( Schedonorus phoenix). The 2006 Farm Bill included the mid-contract management (MCM) provision requiring landowners with new CRP enrollments to provide habitat improvement midway through the 10-15-year contract duration. We compared the effects of 3 approved MCM regimes (i.e., fall strip disking, fall glyphosate spraying, fall glyphosate spraying followed by spring legume drill-seeding) on grassland bird communities in 60 tall fescue-dominated CRP fields in south-central Illinois during 2006-2008. We modeled relative density of dickcissels ( Spiza americana), Henslow's sparrows ( Ammodramus henslowii), and eastern meadowlarks ( Sturnella magna) as a function of microhabitat, patch-level patterns, and landscape composition using a multi-scale assessment approach. We detected 10 grassland-associated bird species (e.g., Henslow's sparrow, northern bobwhite [ Colinus virginianus], sedge wren [ Cistothrus platensis], Savannah sparrow [ Passerculus sandwichensis], grasshopper sparrow [ Ammodramus savannarum]) that are recognized as species of greatest need for conservation under the Illinois State Wildlife Action Plan. Mean total bird densities and species richness were greater in glyphosate-sprayed fields (5.0 birds/ha; 11.5 species) and glyphosate drill-seeded fields (4.4 bird/ha; 12.4 species) than in disked (3.4 birds/ha; 8.7 species) and reference (3.1 birds/ha; 7.5 species) fields. The avian conservation value of glyphosate sprayed and glyphosate drill-seeded fields increased 34.2% and 32.6% post-management, respectively, but we did not detect change in disked and reference fields. Our models indicate that density of each of the focal species is likely associated with changes in plant species diversity and habitat structure resulting from management actions but is also influenced by landscape composition. Despite an overall positive response of the grassland bird communities to glyphosate-based treatment regimes in tall fescue CRP fields in south-central Illinois, the response of Henslow's sparrow density to glyphosate was not consistently positive. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Land managers must balance the needs of a variety of species when manipulating habitats. Structured decision making provides a systematic means of defining choices and choosing among alternative management options; implementation of a structured decision requires quantitative approaches to predicting consequences of management on the relevant species. Multi-species occupancy models provide a convenient framework for making structured decisions when the management objective is focused on a collection of species. These models use replicate survey data that are often collected on managed lands. Occupancy can be modeled for each species as a function of habitat and other environmental features, and Bayesian methods allow for estimation and prediction of collective responses of groups of species to alternative scenarios of habitat management. We provide an example of this approach using data from breeding bird surveys conducted in 2008 at the Patuxent Research Refuge in Laurel, Maryland, evaluating the effects of eliminating meadow and wetland habitats on scrub-successional and woodland-breeding bird species using summed total occupancy of species as an objective function. Removal of meadows and wetlands decreased value of an objective function based on scrub-successional species by 23.3% (95% CI: 20.3-26.5), but caused only a 2% (0.5, 3.5) increase in value of an objective function based on woodland species, documenting differential effects of elimination of meadows and wetlands on these groups of breeding birds. This approach provides a useful quantitative tool for managers interested in structured decision making. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The article reports the results of surveys conducted by the author which focuses on the characterizations of various water-bird and land-bird species in different parts of Killin Wetlands in Portland, Oregon. It further briefs about the habitats, breeding status, migratory status and conservation status of various species of birds. It also briefs about the vulnerable and critical populations of birds in this area. It further suggests that the author was able to characterize seventy five species within a span of three years. The author further emphasized on the need of conducting surveys in order to gain better understanding of the composition and abundance of birds that are breeding in this area.

Remediation of lands devastated by industry includes various forms of restoration, such as technical reclamation and spontaneous succession. These management approaches are debated regarding conservation strategies for postindustrial landscapes. Mining areas consisting of early- to late-developmental stages of both reclaimed and unreclaimed sites offer an opportunity to examine the roles of restoration strategies in a complete successional series for biodiversity and disentangle the contributions of particular biotopes available at postindustrial sites., Using linear models and multivariate analysis, I tested the effects of (a) developmental stages from early successional sites to mature forests, combined with (b) the initiation process at the sites, which was either technical reclamation or spontaneous succession, and (c) vegetation cover on (i) species richness, (ii) rarity and (iii) species composition of bird communities on 60 plots (100 × 100 m) within opencast mining areas in the lignite basin of north-western Czech Republic., Bird communities were consistently more species rich on spontaneously developed sites compared with reclaimed sites throughout all stages of the succession series. Species richness increased with site age due to increasing habitat heterogeneity., The conservation value of bird communities was generally lower on reclaimed sites than on spontaneously developed sites and decreased with site age. The most valuable communities developed on early successional sites and native shrublands, because these were inhabited by specialists that were scarce in the surrounding landscape. By contrast, technically reclaimed sites resulted in impoverished communities, usually with narrow spectra of common species., Synthesis and applications. The results highlight the importance of spontaneously established sites and complete succession series for developing valuable bird communities in postindustrial areas such as opencast mining sites. In particular, early successional sites and shrublands create refuges for early successional specialists disappearing from the common landscape and these should be promoted at the expense of reclaimed sites wherever possible. My results support an effort for systematic implementation of early successional sites into conservation practice. [ABSTRACT FROM AUTHOR]

Aim Temporal variation in animal-landscape relationships hinders management decisions and development of conservation policy. Animal-landscape relationships may be modelled using several model selection criteria ( MSC), but how such criteria affect measures of temporal variation of modelled relationships is unclear. Location Appalachian Mountains, USA. Methods We used results from linear and logistic regression models for 98 bird species over a 5-year period to compute two measures of interannual variation in bird-landscape relationships: model consistency reflected the degree to which variables and directions of relationships in a model were the same. R2 coefficient of variation ( R2 CV) reflected the degree to which the strength of relationships was the same. We calculated both metrics for each species' models after using four common MSC: AICc, BIC, stepwise-0.15 and adjusted R2. Results Although positively correlated ( r = 0.43−> 0.99; P = 0.030−< 0.001), interannual variation metrics for species differed up to 80% among different MSC. One exception was that using stepwise-0.15 and AICc resulted in identical bird-landscape models > 90% of the time and thus produced the same interannual variation metrics for those models. MSC affected R2 CV less than model consistency. Model consistency did not differ significantly among MSC. Use of BIC led to the highest R2 CV (greatest interannual variation), and use of AICc and stepwise-0.15 led to the lowest R2 CV. Main conclusions Comparisons of interannual variation metrics across studies or regions should be based on models derived from the same MSC. When cross-study comparisons must be made, effects of MSC on interannual variation in the strength of relationships ( R2 CV) may be smaller than effects of MSC on interannual variation in the identity of relationships (model consistency). Model consistency metrics could potentially be used in concert with other model evaluation criteria to refine landscape-based species conservation planning. [ABSTRACT FROM AUTHOR]

The current altitudinal distribution and breeding observations on birds of lower Palni Hills, Western Ghats were documented by conducting road transects, opportunistic surveys including trail walks and mist netting. A total of 196 species belonging to 63 families were recorded during the study. The Accipitridae family was foremost in species richness, followed by Cuculidae and Muscicapidae, Picidae, Timaliidae and other families. Altitudinal distribution of birds was higher between 600 and 900 m. The general patterns of the decreasing species richness with increasing altitude were observed in mid and upper Palnis. This could be probably because the lower Palnis have more deciduous and scrub forest which can support high food availability. Resident and migrant species made up to 87.76% and 12.24% of the community, respectively. We recorded a species that was threatened, three nearly threatened, and five endemic to the Western Ghats. Most of the endemics were confined to the higher altitudes due to the presence of moist evergreen and high altitude montane forests and grasslands. In total, 51 breeding bird observations were recorded. Interestingly, the variation in the breeding season of some birds was noticed with respect to earlier studies. Overall, our study illustrated useful information on bird community in this region which serves as a baseline for future monitoring programs. [ABSTRACT FROM AUTHOR]