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Interest in regenerating oaks (Quercus spp.) has promoted use of partial harvesting techniques that create an open forest structure. From 2007 to 2009, we studied songbirds in mixed-oak forests in southeastern Ohio, comparing shelterwoods recently harvested to 50% stocking and closed-canopy mature second-growth. We surveyed birds using distance-based methods (56 line transects in 18 stands at 4 forests). We intensively investigated suitability of shelterwoods for canopy-nesting species by examining habitat preferences, as measured by settlement patterns, age distributions, and site fidelity; we also examined nesting success. Several midstory and ground-nesting species were 26-73% less abundant in shelterwood than unharvested stands, whereas shrub-nesting species increased >100% several years post-harvesting. Canopynesting species were 31-98% more abundant in shelterwoods, but cerulean warbler (Setophaga cerulea) responses varied by forest. Patterns of settlement and site fidelity were generally similar among stands. Proportions of young males were actually greater for several species in shelterwood than unharvested stands, which may have been a consequence of young birds colonizing newly created (or improved) habitat. Even in our predominantly forested study system, nesting success (>700 nests) was low, ranging from 15% to 19% for yellow-throated vireos (Vireo flavifrons) and cerulean warblers, to 27-36% for scarlet tanagers, blue-gray gnatcatchers (Polioptila caerulea) and eastern wood-pewees (Contopus virens). However, nest survival did differ between shelterwood and unharvested stands, possibly because numbers of avian predators did not change with harvesting. Despite increased numbers of brown-headed cowbirds (Molothrus ater) in shelterwoods, only 2% of canopy nests in which young could be identified were parasitized. Although these results suggest shelterwood harvests containing abundant overstory trees can provide short-term breeding habitat for canopy songbirds, long-term responses of birds to partial harvesting may differ from those documented here depending on different management options employed. Management for oak regeneration will typically remove all overstory trees later in the cutting cycle, initially resulting in loss of nesting substrates and hence breeding habitat for canopy songbirds.

The worldwide increase in human outdoor activities raises concerns for wildlife. Human disturbances, even at low levels, are likely to impact species during sensitive periods of the annual cycle. However, experimental studies during the putative sensitive period of territory establishment of birds which not only investigate low disturbance levels, but which also exclude the effect of habitat modification (e.g. walking trails) are lacking. Here, we experimentally disturbed birds in forest plots by walking through twice a day during territory establishment. Later we compared the breeding bird community of experimentally disturbed plots with that of undisturbed control plots. We discovered that the number of territories (−15.0%) and species richness (−15.2%) in disturbed plots were substantially reduced compared with control plots. Species most affected included those sensitive to human presence (assessed by flight-initiation distances), open-cup nesters and above-ground foragers. Long-distance migrants, however, were unaffected due to their arrival after experimental disturbance took place. These findings highlight how territory establishment is a sensitive period for birds, when even low levels of human recreation may be perceived as threatening, and alter settlement decisions. This can have important implications for the conservation of species, which might go unnoticed when focusing only on already established birds.

Surface coal mining and subsequent reclamation efforts in the Appalachian Mountains, USA, transform the ecological characteristics of natural landscapes. The Forestry Reclamation Approach (FRA) is a mine reclamation method that emphasizes best management practices in forestry. FRA practices have demonstrated success in establishing native forests and accelerating natural succession on coal mines; however, no studies have empirically examined the effects of the FRA on bird communities. Our study aimed to assess the avian community composition within young forests reclaimed using the FRA after one decade of forest growth. Whereas traditional reclamation practices often support grassland avian guilds, we expected that the FRA would provide habitat for shrubland and young forest avian guilds. Moreover, we sought to determine whether FRA forests would contain known avian indicator species of the native forest land cover. In June 2022, we conducted point count surveys in high‐elevation, red spruce‐northern hardwood (RS‐NH) forests in the Appalachian Mountains of eastern West Virginia, USA. Using Bayesian multispecies occupancy models, we assessed avian guild occupancy and species richness within two FRA forest age classes (2–5 years and 8–11 years). We also examined avian community composition within two older RS‐NH reference age classes to predict the future avian composition within FRA forests if reclamation succeeds. We found that the FRA breeding bird community included all of the avian indicator species expected to inhabit a young RS‐NH forest. These results suggest that after approximately one decade, legacy mines reclaimed using the FRA are progressing toward a native RS‐NH forest that supports associated forest bird communities.

Interaction between nature and human has formulated unique biodiversity in temperate regions. People have conserved and maintained traditional folk villages (TFVs) dominated with houses made of natural materials, arable land and surrounding elements of landscape. Until now, little attention has been given to understand the traits of breeding birds in TFVs of Korea. The aim of this study was to reveal traits of breeding birds in TFVs and get conservative implications for biodiversity. We selected five TFVs: Hahoe maeul (HA), Wanggok maeul (WG), Nagan maeul (NA), Yangdong maeul (YD), and Hangae maeul (HG). We surveyed breeding birds with line transect methods, and analyzed functional traits (diet type and nest type) of birds in TFVs. Among 60 species recorded, Passer montanus (PM), Streptopelia orientalis (SO), Hirundo rustica (HR), Pica pica (PP), Phoenicuros auroreus (PA), Paradoxornis webbiana (PW), Microscelis amaurotis (MA), Carduelis sinica (CA) and Oriolus chinensis (OC) could be potential breeding birds that prefer diverse habitats of TFVs in Korea. Compared to the breeding birds of rural, urban and forest environments, the diversity of nesting types for birds was high in TFVs. The diverse nest types of breeding birds can be linked with habitat heterogeneity influenced by sustainable interaction between nature and human in TFVs in Korea.

Biodiversity conservation in urban areas has become increasingly important as cities have expanded to cover larger proportions of landscapes across the world. The careful planning of habitat reserves within urbanized areas has the potential to make significant contributions to regional biodiversity. We surveyed the passerine community in 15 habitat reserves within the Phoenix metropolitan region and explored the relationships between community composition and urban land uses surrounding the reserves. Diversity of different guilds was affected in substantially different ways by reserve characteristics and surrounding urban land use. Guilds responded to land use at all three scales included in the study – 200 m, 1000 m and 2500 m. The responses of four guilds, synanthropic, non-synanthropic, insectivore and feeding generalist, were well predicted by the factors considered here. Reserve characteristics (area, shape, isolation), particularly area, had effects on all four of these guilds with non-synanthropic and insectivore species responding positively to area, while synanthropic and feeding generalist species responded negatively. Land use type surrounding the reserves had significant effects on all of these guilds, except for feeding generalists. High density, high diurnal activity land uses decreased diversity, while medium density, low diurnal activity uses increased the diversity of some guilds, particularly insectivores, probably by providing supplemental habitat. This study provides new evidence from an arid urban landscape that not only reserve characteristics, but also surrounding urban land use should be considered during conservation planning, especially if non-synanthropic or insectivore species are among the targeted species.

The nests of ground‐nesting birds rely heavily on camouflage for their survival, and predation risk, often linked to ecological changes from human activity, is a major source of mortality. Numerous ground‐nesting bird populations are in decline, so understanding the effects of camouflage on their nesting behavior is relevant to their conservation concerns. Habitat three‐dimensional (3D) geometry, together with predator visual abilities, viewing distance, and viewing angle, determine whether a nest is either visible, occluded, or too far away to detect. While this link is intuitive, few studies have investigated how fine‐scale geometry is likely to help defend nests from different predator guilds. We quantified nest visibility based on 3D occlusion, camouflage, and predator visual modeling in northern lapwings, Vanellus vanellus, on different land management regimes. Lapwings selected local backgrounds that had a higher 3D complexity at a spatial scale greater than their entire clutches compared to local control sites. Importantly, our findings show that habitat geometry—rather than predator visual acuity—restricts nest visibility for terrestrial predators and that their field habitats, perceived by humans as open, are functionally closed with respect to a terrestrial predator searching for nests on the ground. Taken together with lapwings' careful nest site selection, our findings highlight the importance of considering habitat geometry for understanding the evolutionary ecology and management of conservation sites for ground‐nesting birds. We used 3D scanning and color‐calibrated images to investigate the effects of local geometry on ground‐nesting bird site selection and camouflage. We found that lapwings, Vanellus vanellus, locally select for more 3D variable areas and that the scale and shape of their nests restrict visibility more than predator visual acuity, with crop fields and wet grassland acting more like a closed habitat from the viewing angles of natural predators.

Mounting evidence suggests declines in the abundance and diversity of wild bees. Increasing habitat that provides forage and nesting sites could boost struggling populations, particularly in urban, suburban and agricultural landscapes. The millions of acres beneath aerial electric transmission lines, sometimes referred to as easements or rights-of-way, must be kept free of tall-growing vegetation and hence have the potential to provide suitable habitat for many native species. Prior work has demonstrated that bee communities in easements managed using alternatives to episodic mowing were more diverse than in nearby open areas, however true control sites within the easements were unavailable. In order to compare vegetation management protocols, we conducted a two-year study which enabled us to directly compare transmission line easements in three locations currently undergoing Integrated Vegetation Management—a dynamic form of management involving spot removal and herbicide treatment of unwanted species (treatment) with nearby sites undergoing standard management protocols of yearly or biyearly mowing (control). Results show that treatment sites had significantly higher abundance and species richness than controls. Seasonal differences were pronounced, with the spring fauna most affected by differences in vegetation management. In addition, the older treatment sites house more social bees, more parasitic species and a more even distribution of bees across nesting guilds. Finally, we established that treatment sites had distinct bee communities, further increasing their value as sources for native bee populations in the landscape. Overall, the data clearly show the value of implementing alternative active vegetation management in the land under powerlines to achieve an increase in the abundance and diversity of wild bees.

Fire, a frequent disturbance in the Mediterranean, affects pollinator communities. We explored the response of major pollinator guilds to fire severity, across a fire-severity gradient at different spatial scales. We show that the abundance of all pollinator groups responded to fire severity, and that bees and beetles showed in addition a significant species-diversity response. Bees, sawflies, and wasps responded to fire severity at relatively small spatial scales (250–300 m), whereas flies and beetles responded at larger spatial scales. The response of bees, sawflies, and wasps was unimodal, as predicted by the intermediate disturbance hypothesis, whereas flies and beetles showed a negative response. A possible explanation is that the observed patterns (spatial scale and type of response) are driven by taxa-specific ecological and life-history traits, such as nesting preference and body size, as well as the availability of resources in the postfire landscape. Our observational study provides an insight into the effect of fire severity on pollinators. However, future research exploring the explicit link between the pre- and postfire landscape structure and pollinator traits and responses is required for further establishment and understanding of cause–effect relationships.

Altitudinal migration is the seasonal altitudinal movement of birds from breeding areas to non-breeding or wintering areas at different elevations. Although this type of migration is widely reported, questions remain concerning the number of species that perform altitudinal migration, possible variation among different taxa and geographic locations in the extent of altitudinal migration, and the foraging guilds of altitudinal migrants. We conducted an extensive bibliographic survey and compiled a list of altitudinal migrant birds worldwide. We characterized species in terms of their foraging guilds because the spatial distribution of food resources along altitudinal gradients is often evoked as a driver of bird altitudinal migration. We identified 1238 species of altitudinal migrants, ~10% of the ~10,000 extant species of birds. We found a strong geographic bias in publications focusing on avian altitudinal migration toward the United States and Costa Rica, and a paucity of studies in megadiverse regions such as the Afrotropical and Indomalayan realms, and areas in the Neotropics other than Costa Rica. We also found that most species of altitudinal migrants were invertivores rather than frugivores or nectarivores. This general pattern held true for all zoogeographic realms except the Neotropics, where nectarivores and frugivores predominated among altitudinal migrants. The prevalence of invertivore birds among altitudinal migrants is not unexpected because this is the most common foraging guild among birds worldwide. Overall, we found no prevalence of any specific foraging guild among altitudinal migrants across zoogeographic regions. The results of studies to date suggest that altitudinal migration by birds may be driven by a number of factors, including access to increased food resources for breeding or molting, weather conditions, and mating and nesting opportunities. However, to better understand the mechanisms underlying altitudinal migration, broadening the geographic scope of studies is paramount, with additional study of altitudinal migration especially needed in the megadiverse tropical regions of sub-Saharan Africa, Southeast Asia, and South America. La migración altitudinal es el movimiento altitudinal estacional de las aves desde las áreas de reproducción a las áreas no reproductivas o de invernada a diferentes elevaciones. Aunque este tipo de migración es ampliamente reportado, quedan preguntas sobre el número de especies que realizan migración altitudinal, la posible variación entre direrentes taxones y ubicaciones geográficas en el grado de migración altitudinal, y los gremios de forrajeo de migrantes altitudinales. Realizamos una extensa encuesta bibliográfica y compilamos una lista de aves migratorias altitudinales en todo el mundo. Caracterizamos a las especies en términos de sus gremios de forrajeo porque la distribución espacial, y por los gradientes altitudinales, de los recursos de alimentación muchas veces se evoca como un impulsor de la migración altitudinal de las aves. Identificamos 1238 especies de migrantes altitudinales, ~ 10% de las ~ 10,000 especies de aves existentes. Encontramos un fuerte sesgo geográfico en las publicaciones que se enfoque en la migración altitudinal de las aves en los Estados Unidos y Costa Rica, y una escasez de estudios en regiones megadiversas como los regiones de Afrotropical e Indomalayan, y áreas en el Neótropico además de Costa Rica. También encontramos que la mayoría de las especies de migrantes altitudinales eran invertívoros en vez de frugívoros nectarívoros. Este patrón general se mantuvo para todas las regiones zoogeográficos, excepto el Neotrópico, donde los nectarívoros y frugívoros predominaron entre los migrantes altitudinales. La prevalencia de aves invertívoras entre los migrantes altitudinales no es inesperada, ya que es el gremio de forrajeo más común entre las aves en todo el mundo. En general, no encontramos prevalencia de ningún gremio de forrajeo específico entre todos los migrantes altitudinales en las regiones zoogeográficas. Los resultados de los estudios hasta ahora sugieren que la migración altitudinal de las aves puede estar impulsada por una serie de factores, incluido el acceso a mayores recursos alimentarios durante la cría o muda, las condiciones climáticas y las oportunidades de apareamiento y anidación. Sin embargo, para comprender mejor los mecanismos subyacentes a la migración altitudinal, es primordial a ampliar el alcance geográfico de los estudios, con estudios de la migración altitudinal especialmente necesario en las regiones tropicales y megadiversas del África subsahariana, el sudeste asiático y Sudamérica.

ContextFire influences the distribution of ecosystems on Earth, but the link between pyrodiversity, the heterogeneity in post-fire conditions, and biodiversity is just emerging.ObjectivesWe tested the pyrodiversity begets biodiversity theory, which was developed at broader scales, to a scale where land management decisions are commonly made.MethodsTo assess the effects of landscape attributes on avian species richness, we deployed programmable acoustic recorders at 34 sites in a frequently burned longleaf pine (Pinus palustris) ecosystem which were set to record three, five–minute sessions per day for six days for two years. We identified avian species by their vocalizations and grouped them by nesting and forging guilds to assess the effects of land cover type, soil productivity, forest structure and fire history characteristics including, pyrodiversity on species richness and occupancy at the community, guild, and species levels using hierarchical Bayesian multispecies occupancy models. We defined pyrodiversity as the richness in time since fire values around a site.ResultsWe found support for the pyrodiversity begets biodiversity hypothesis at the community level, as avian species richness increased with pyrodiversity (β = 0.136, 95% CrI 0.009–0.260). Species richness of cavity nesting species decreased with increasing time since fire, suggesting frequent fire increases diversity of this guild (β =  − 0.334, 95% CrI − 0.713 to − 0.003).ConclusionsOur work highlights the importance of pyrodiversity as a driver for biodiversity, and links theory to practices by examining this phenomenon at a scale readily translated into conservation action.