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High exposure to warming from climate change is expected to threaten biodiversity by pushing many species toward extinction. Such exposure is often assessed for all taxa at a location from climate projections, yet species have diverse strategies for buffering against temperature extremes. We compared changes in species occupancy and site-level richness of small mammal and bird communities in protected areas of the Mojave Desert using surveys spanning a century. Small mammal communities remained remarkably stable, whereas birds declined markedly in response to warming and drying. Simulations of heat flux identified different exposure to warming for birds and mammals, which we attribute to microhabitat use. Estimates from climate projections are unlikely to accurately reflect species’ exposure without accounting for the effects of microhabitat buffering on heat flux. [ABSTRACT FROM AUTHOR]

The article discusses the ecological success of Homo sapiens and disappearance and then the return of the Bearded Vulture Gypaetus barbatus. Topics discussed include White Stork Ciconia ciconia birds species, reintroduction of the species in the Alps and breeding and migration of birds in Switzerland.

Monitoring trends in the extinction risk of species is important for tracking conservation effectiveness. The Red List index (RLI) reflects changes in aggregate extinction risk for sets of species over time (a value of zero means that all species are extinct, a value of one means that all species are categorized as Least Concern). We calculated the first national RLI for birds in Colombia for the period 2002–2016, and disaggregated indices by ecosystems, regions, and species groups. Overall, the status of birds in Colombia has moderately deteriorated during 2002–2016, declining by 0.0000714% per year (the global RLI for birds declined by 0.0297% per year). High Andean forest, paramo, and freshwater are the ecosystems in worst condition. The two regions with the greatest avian diversity contrasted: the Andes has the lowest RLI, and the Amazon the highest. Among species groups, gamebirds, parrots, large frugivores, and forest raptors are the most threatened. Habitat loss from expansion of illicit crops and population declines from hunting were the most important threats. Agricultural expansion, invasive alien animal species, illegal logging and illegal mining are significant threats for some species. Tracking species' extinction risk is important in a country with the highest bird species richness in the world, dynamic spatial patterns of habitat loss, and high levels of endemism. Recent developments provide reasons for both hope and despair. In 2016, a peace agreement ended 50 years of armed conflict. New opportunities for biodiversity conservation, local development based on bird-watching tourism, and advancement in scientific knowledge of birds now occur alongside dramatic increases in deforestation. These new conservation opportunities and challenges provide strong motivation to take advantage of the fact that the overall risk of extinction of birds in Colombia is still relatively low and stable. Effective action is urgently needed while there still is the opportunity to prevent extinctions and safeguard species, particularly those in higher risk categories. [ABSTRACT FROM AUTHOR]

In 2006, after centuries of absence, a pair of white-tailed eagles (Haliaeetus albicilla) bred successfully in the Netherlands. Since then, the species has slowly spread across the country. The white-tailed eagle's return is a consequence of its spectacular increase in Northern Europe and Germany, and the westward expansion of the breeding area. At least one bird of the first breeding pair hatched in Schleswig-Holstein, Northern Germany. [ABSTRACT FROM AUTHOR]

Only around a third of the world's remaining forest cover survives in the form of Intact Forest Landscapes (IFL), and that proportion is declining. Loss of intactness could impact on biodiversity in many ways but the relationship between intactness and extinction risk has not been quantified. We created Extent of Suitable Habitat (ESH) maps for all the world's forest‐dependent birds and intersected them with an independently derived IFL layer. We also estimate the proportion of the total global range‐rarity of forest‐dependent birds that is captured by IFL. The majority of forest‐dependent bird species are now confined largely or entirely to be degraded, disturbed, or fragmented (non‐IFL) forests. Furthermore, only 22.5% of global hotspots of range‐rarity for forest‐dependent birds are found within intact forests. We find a very strong positive relationship between the global extinction risk of forest‐dependent birds and the proportion of forest within their ESH that is no longer intact. This effect was independent of overall range size and phylogeny. There was also a tendency for extinction risk to be higher in species that lost more intactness in their forest ESHs between 2000 and 2016. Restoring intactness to forest landscapes will reduce global extinction risk in forest‐dependent birds. [ABSTRACT FROM AUTHOR]

Globally, conversion of natural habitats to farmland poses the greatest extinction risk to birds, its consequences being especially pervasive in the case of large predators and scavengers, whose declines may trigger extensive cascading effects. Human population growth in sub-Saharan Africa is expected to drive a vast expansion in agricultural land by 2050, largely at the expense of pastoral land and savanna. The greatest expanse of suitable land yet to be converted to agriculture lies in East and Central Africa, including South Sudan, DRC and Tanzania. To gauge the effects of land conversion on raptor populations in this region we used road survey data from neighbouring Uganda, from which we determined linear encounter rates (birds seen 100 km−1; n = 33 species), and species richness (from 53 species). Encounter rates were much lower in pastoral land than in protected savanna (median difference: −41%; 23 species), and lower still in agricultural land (−90%; 24 species). These disparities were influenced by diet and body mass. For large eagles and vultures, encounter rates in agricultural land were 97% lower than in protected savanna (median of 12 species), whereas for smaller raptors they were 30% lower (12 species). Large, apex consumers were thus more vulnerable to farmland expansion, and this was reflected in the mean body mass of species encountered in savanna (1740 g), pastoral (995 g) and agricultural land (856 g). Body mass differences remained significant when vultures were excluded. Since threat status is linked to body mass, encounter rates for globally threatened and near-threatened species likewise showed a more pronounced deficit in farmland than those of least concern. Accordingly, pastoral and agricultural transects were less species-rich (10.6 and 6.7 raptor species 100 km−1, respectively) than savanna transects (13.2 species). Our findings suggest that the expansion of agricultural land in sub-Saharan Africa will reduce raptor populations in pastoral land and savanna by c. 50% and 90%, respectively. We propose that conservation efforts focus on identifying the causes of raptor population deficits in farmland, and on safeguarding tracts of unprotected, intact savanna, together with existing protected areas. [ABSTRACT FROM AUTHOR]

The endemic fauna of New Zealand evolved in the absence of mammalian predators and the introduction of the latter has been devastating. There have been numerous avian extinctions and 80% of the extant native avian taxa are currently threatened or at risk of extinction. Declines continue, and a fundamental change in predator management is required. In 2016 came the announcement of the ambitious Predator Free 2050 (PF 2050) programme, which aims to eradicate rats, mustelids, and Brushtail Possums from New Zealand by 2050. This paper reviews some of the many techniques being discussed or developed to implement the programme. Existing techniques are being refined and new tools are being developed. Research on new toxins, including those with potentially higher species specificity, is under way, and novel baits and toxin-delivery devices are being developed. Existing trap designs are being refined, and new self-resetting traps capable of multiple kills have been developed. Research is also under way on new lures and repellents. Eradications may be achieved in stages, and barriers (both natural and artificial) will be needed to protect areas already cleared. Current techniques will probably be inadequate to effect nationwide eradications, and new tools (possibly based on genetic technologies) will probably be required. Regulatory hurdles will need to be overcome, and community consultation and support (social licence) will be required throughout the programme. The use of some new technologies may be contentious, and not every new idea will necessarily be adopted. Technical, social, and organisational challenges exist, and national and international collaboration will be required for PF 2050 to succeed. [ABSTRACT FROM AUTHOR]

This paper explores cultural geographies of extinction. I trace the decline of the Scottish osprey during the 19th century and its enduring, haunting presence in the landscape today. Taking inspiration from the environmental humanities, extinction is framed as an event affecting losses that exceed comprehension in terms merely of biological species numbers and survival rates. Disavowing the "species thinking" of contemporary conservation bio‐politics, the osprey's extinction story pays attention to the worth of "animal cultures." Drawing a hybrid conceptual framework from research in the environmental humanities, "speculative" ethology and more‐than‐human geographies, I champion an experimental attention to the cultural geographies of animals in terms of historically contingent, communally shared, spatial practices and attachments. In doing so, I propose non‐human cultural geographies as assemblages that matter, and which are fundamentally at stake in the face of extinction. [ABSTRACT FROM AUTHOR]

Geospatial patterns in the distribution of regional biodiversity reflect the composite processes that underpin evolution: speciation, dispersal and extinction. The spatial distribution and phylogeny of a globally widespread and species rich bird family (Rallidae) were used to help assess the role of large‐scale biogeographical processes in diversity and diversification. Here, we examine how different geostatistical diversity metrics enhance our understanding of species distribution by linking occurrence records of rail species to corresponding species level phylogeny. Tropical regions and temperate zones contained a large proportion of rail species richness and phylogenetic diversity whilst small islands in Australian, Oceanian and Oriental regions held the highest weighted and phylogenetic endemism. Our results suggest that habitat connectivity and dispersal were important ecological features in rail evolution and distribution. Spatial isolation was a significant driver of diversification where islands in Oceania were centres of neo‐endemism with recent multiple and independent speciation events and could be considered as nurseries of biodiversity. Palaeo‐endemism was mostly associated with older stable regions, so despite extensive long distance range shifting these areas retain their own ancient and distinct character. Madagascar was the major area of palaeo‐endemism associated with the oldest rail lineages and could be considered a museum of rail diversity. This implies a mixture of processes determine the current distribution and diversity of rail clades with some areas dominated by recent 'in situ' speciation while others harbour old diversity with ecological traits that have stood the test of time. [ABSTRACT FROM AUTHOR]

Highlights • Inactivation of the avian visual associative NFL slows extinction learning. • Distinguishing different visual stimuli was unaffected after NFL inactivation. • NFL inactivation abolishes the renewal effect. Abstract Extinction learning is a fundamental learning process that enables organisms to continuously update knowledge about their ever-changing environment. When using visual cues as conditioned stimuli (CS), visual cortical areas of mammals are known to participate in extinction learning. The aim of the present study was to test whether similar processes can also be observed in birds. With pigeons as an animal model, we therefore investigated the role of the nidopallium frontolaterale (NFL), a key avian visual associative area, in an extinction learning task. We adopted a within-subject extinction task design with context manipulation, and tested the animals for extinction memory retention and renewal. Before extinction, the NFL was transiently inactivated by intracerebral tetrodotoxin (TTX) injections. Our data suggest that inactivation of NFL indeed produces a slowing of extinction learning. Importantly, NFL also plays a key role in context encoding, as indicated by an abolishment of the renewal effect. This is not due to an overall perceptual decrement, since the ability to distinguish between the different visual stimuli was unaltered, but might be caused by an impaired formation of the context-CS-configuration during extinction. Taken together, our experiment not only reveals similarities of neural substrates of extinction learning in birds and mammals, but also provides strong evidence for a specific contribution of the NFL in context encoding. [ABSTRACT FROM AUTHOR]

Abstract Asian Gyps vulture species are gradually recovering from the devastating effect of diclofenac being present in contaminated carcasses. This drug was responsible for the death of over 10 million vultures in India, Nepal and Pakistan. To prevent the extinction of vultures, meloxicam was introduced after the ban of veterinary diclofenac. Meloxicam's safety in vultures was attributed to its short elimination half-life in contrast with diclofenac. The reason for the rapid elimination of meloxicam is yet to be explained. The aim of this study was to evaluate the role of biotransformation in the elimination of meloxicam. Six Cape griffon vultures (Gyps coprotheres) were treated with 2 mg/kg meloxicam intramuscularly for faecal and plasma quantification of meloxicam concentration over time. In the plasma meloxicam was characterised by a half-life, mean residence time, clearance and volume of distribution at steady state of 0.37 ± 0.10 h, 0.90 ± 0.12 h, 0.02 ± 0.00 l/h kg and 0.02 ± 0.00 l/kg respectively (presented as geometric mean). Over the 24 h monitoring period, the total non-metabolised meloxicam in the faeces was 1.35 ± 0.71% of the total concentration in the plasma. Based on the short meloxicam elimination half-life and low cumulative concentration of total faecal meloxicam over a period in excess of 10 half-lives, this study indicates that Cape griffon vultures are efficient metaboliser of meloxicam, which is suggestive of different set of cytochrome enzymes being involved in the metabolism to that for diclofenac in this species. Identification of orthologous human CYP2C9 and CYP3A4 enzyme families in vultures will be an important further step in explaining the differences in the metabolic pathway(s) of meloxicam and diclofenac for the species. Highlights • Develop and validate a high performance liquid chromatography (HPLC) for the quantification of meloxicam in vulture faeces. • Evaluate pharmacokinetic parameter of meloxicam in Cape vulture 10 h post administration using HPLC. • Evaluate faecal concentration of non-metabolised meloxicam 24 h post administration using HPLC method. • Investigate the reason (s) for meloxicam safety in old world vultures. [ABSTRACT FROM AUTHOR]

Gamla Nature Reserve (GNR) used to host the largest colony of Eurasian griffon vultures (Gyps fulvus) in northern Israel. Since the early 2000s, the colony has suffered a drastic decline, which could lead to its extinction. In this descriptive study we present the population dynamics at GNR based on an analysis of data collected over 15 years (1999–2013). A monitoring scheme of monthly counts, developed at GNR, provided a database, facilitating a mathematical analysis of the population decline trends and their seasonal fluctuations. The analysis revealed a decline in the population size, which appears similar to an inverse‐sigmoid and indicates a potential extinction of the colony by 2020. The analysis also indicates that, in addition to the overall pattern, the number of vultures fluctuates seasonally, with smaller numbers in spring and greater numbers in autumn and winter. Furthermore, this model suggests that latent factors might have influenced the decline; poisoning, thought to be a root cause, might not be the only factor influencing extinction. We demonstrate the importance of combining frequent data collection with modeling techniques for the analysis of raptor population trends. © 2018 The Wildlife Society. The griffon vulture (Gyps fulvus) population at the Gamla Nature Reserve counted during 1999–2013 exhibited intra‐annual seasonal fluctuations and a long‐term inter‐annual decline. Although it is commonly suggested that the population decline is associated with poisoning events, our analysis indicates that latent factors, yet to be explored, may also have a role in this pattern. [ABSTRACT FROM AUTHOR]

The overwhelming majority of avian extinctions have occurred on islands, where introduced predators, habitat loss, disease, and human persecution have resulted in the loss of over 160 species in the last 500 years. Understanding the timing and causes of these historical extinctions can be beneficial to identifying and preventing contemporary biodiversity loss, as well as understanding the nature of island ecosystems. Tristan da Cunha (henceforth "Tristan"), the most remote inhabited island in the world, has lost three species from the main island since permanent human settlement in 1811—the Tristan Moorhen (Gallinula nesiotis), Inaccessible Finch (Nesospiza acunhae acunhae), and Tristan Albatross (Diomedea dabbenena). We used recently developed Bayesian methods, and sightings of mixed certainty compiled from historical documents, to estimate the extinction date of these three species from Tristan based on specimens. We estimate that all three species were likely extirpated from Tristan between 1869 and 1880 following a period of significant habitat alteration and human overexploitation, and only the albatross had a high probability of persistence when Black Rats (Rattus rattus) arrived in 1882, the previously assumed cause of extinction for all three species. Better estimates of extinction dates are essential for understanding the causes of historical biodiversity loss, and the combination of historical ecology with modern statistical methods has given us novel insights into the timing and therefore the causes of extinctions on one of the most isolated islands in the world. [ABSTRACT FROM AUTHOR]

The article examines transnational conservation efforts for the few remaining birds of the Fennoscandian population of the Lesser White-fronted Goose (anser erythropus), colloquially known as ‘Lessers': a tiny, highly endangered population of migrant birds that breeds in Finnmark. Topics discussed include volatile environments of the Anthropocene; danger of extinction due to hunting; and changes in the migration route of the Fennoscandian flock.

The article provides information on the overview data of recent bird watching from November 2019 to January 2020 provided by Swiss Avifauna Commission (CAvS) or the National Approval Committee. Topics discussed include Lapwing Vanellus gregarius on November 5 near Payerne VD, Hume Pouillot Phylloscopus humei was discovered on November 18 in the city of Zurich, in the Chinese garden and Spanish Sparrow Passer hispaniolensis.

This article explores migratory bird conservation policy in North America. It discusses the death of the last passenger pigeon in the U.S., factors that led to the extinction of passenger pigeons, the aim of the Migratory Bird Treaty Act in the U.S., the divide among U.S. courts of appeals over interpretations of the statute's criminal liability, and the statute's imposition of criminal liability on individuals and entities that take protected migratory birds.

Abstract: Land‐cover and climate change are two main drivers of changes in species ranges. Yet, the majority of studies investigating the impacts of global change on biodiversity focus on one global change driver and usually use simulations to project biodiversity responses to future conditions. We conduct an empirical test of the relative and combined effects of land‐cover and climate change on species occurrence changes. Specifically, we examine whether observed local colonization and extinctions of North American birds between 1981–1985 and 2001–2005 are correlated with land‐cover and climate change and whether bird life history and ecological traits explain interspecific variation in observed occurrence changes. We fit logistic regression models to test the impact of physical land‐cover change, changes in net primary productivity, winter precipitation, mean summer temperature, and mean winter temperature on the probability of Ontario breeding bird local colonization and extinction. Models with climate change, land‐cover change, and the combination of these two drivers were the top ranked models of local colonization for 30%, 27%, and 29% of species, respectively. Conversely, models with climate change, land‐cover change, and the combination of these two drivers were the top ranked models of local extinction for 61%, 7%, and 9% of species, respectively. The quantitative impacts of land‐cover and climate change variables also vary among bird species. We then fit linear regression models to test whether the variation in regional colonization and extinction rate could be explained by mean body mass, migratory strategy, and habitat preference of birds. Overall, species traits were weakly correlated with heterogeneity in species occurrence changes. We provide empirical evidence showing that land‐cover change, climate change, and the combination of multiple global change drivers can differentially explain observed species local colonization and extinction. [ABSTRACT FROM AUTHOR]

The endangered Peruvian Plantcutter ( Phytotoma raimondii) is a strictly herbivorous, mostly folivorous passerine endemic to the arid lowlands of northwestern Peru. Previous information obtained from the study of 3 of its major populations consistently suggests the selective use of plant material from the shrub Grabowskia boerhaaviaefolia and Prosopis spp. trees; however, our generalized understanding about the relative importance of these plants could be biased. Some of the Peruvian Plantcutter's populations in which these plants are scarce, and even seemingly absent, have been generally overlooked. We investigated resource use for foraging and nesting by Peruvian Plantcutters at one of these locations. We conducted nest searches inside the area and diet selection analysis in 5 territories of mated pairs. We found 7 nests, built almost exclusively of Scutia spicata twigs, a shrub previously reported for another population as a selected food source along with G. boerhaaviaefolia and Prosopis spp. Here, S. spicata was the food source selected by all mating pairs while Prosopis pallida was scarce overall, selected by just one pair and found only within 2 territories. G. boerhaaviaefolia was not detected throughout the sampling area. This study reveals that the Peruvian Plantcutter occupies a wider range of breeding habitats than previously thought; however, its flexibility in resource use is still expressed within a narrow array of known selected plant species. [ABSTRACT FROM AUTHOR]

Micro-endemic species are at greater risk of extinction because of their small populations and limited distribution. We conducted a breeding population survey of 3 little-known Mexican endemic bird species: Rose-bellied Bunting ( Passerina rositae), Cinnamon-tailed Sparrow ( Peucaea sumichrasti), and Orange-breasted Bunting ( Passerina lechlancherii) in Sierra Tolistoque, Oaxaca. The purpose of the survey was to (a) determine the population density and size of these 3 species in the Sierra Tolistoque, (b) estimate the relative importance of various landscape features for each species, and (c) provide more rigorous scientific information to aid in the conservation and management of these species. In the case of Rose-bellied Bunting, we aimed to assess whether it prefers ravines over other landscape types during the breeding seasons, as stated in previous studies. Between late May and June 2012, we conducted point counts ( n = 209) throughout the southern slope of the Sierra Tolistoque on the Pacific slope of the Isthmus of Tehuantepec, in Oaxaca, Mexico. Overall bird density was 0.98 birds/ha for Rose-bellied Bunting, 0.547 birds/ha for Orange-breasted Bunting, and 0.514 birds/ha for Cinnamon-tailed Sparrow. The estimated population in each landscape category showed that despite the existence of subtle interspecific preferences, hillsides are the major reservoirs for the 3 species. Rose-bellied Bunting did not occur in greater density in ravines compared to hillsides, which comprised more than twice the area of ravines. The importance of the Sierra Tolistoque for the long-term conservation of the 2 micro-endemic species is crucial considering our population estimates suggest that ∼30% of the estimated world population of Rose-bellied Bunting and Cinnamon-tailed Sparrow are found within the range of the Sierra Tolistoque. [ABSTRACT FROM AUTHOR]

Recent increases in human disturbance pose significant threats to migratory species using collective movement strategies. Key threats to migrants may differ depending on behavioural traits (e.g. collective navigation), taxonomy and the environmental system (i.e. freshwater, marine or terrestrial) associated with migration. We quantitatively assess how collective navigation, taxonomic membership and environmental system impact species' vulnerability by (i) evaluating population change in migratory and nonmigratory bird, mammal and fish species using the Living Planet Database (LPD), (ii) analysing the role of collective navigation and environmental system on migrant extinction risk using International Union for Conservation of Nature (IUCN) classifications and (iii) compiling literature on geographical range change of migratory species. Likelihood of population decrease differed by taxonomic group: migratory birds were more likely to experience annual declines than non-migrants, while mammals displayed the opposite pattern. Within migratory species in IUCN, we observed that collective navigation and environmental system were important predictors of extinction risk for fishes and birds, but not for mammals, which had overall higher extinction risk than other taxa. We found high phylogenetic relatedness among collectively navigating species, which could have obscured its importance in determining extinction risk. Overall, outputs from these analyses can help guide strategic interventions to conserve the most vulnerable migrations. [ABSTRACT FROM AUTHOR]

Abstract: Interspecific aggression by the noisy miner (Manorina melanocephala), a highly despotic species, is homogenizing woodland avifaunas across eastern Australia. Although a native species, the noisy miner's aggressive exclusion of small birds is a Key Threatening Process under national law. Large‐scale removal of noisy miners has been proposed as a management response to this threat following increases in miner presence due to anthropogenic land use practices. We tested this proposal by experimentally removing noisy miners from eucalypt woodland remnants (16–49 ha), assigned randomly as control (n = 12) or treatment (miner removal) sites (n = 12). Standardized bird surveys were conducted before and after removal, and generalized linear mixed models were used to investigate the effect of miner removal on bird assemblage metrics. Despite removing 3552 noisy miners in three sessions of systematic shooting, densities of noisy miners remained similarly high in treatment and control sites, even just 14 days after their removal. However, there was evidence of an increase in richness and abundance of small birds in treatment sites compared to controls—an effect we only expected to see if noisy miner densities were drastically reduced. We suggest that miner removal may have reduced the ability of the recolonizing miners to aggressively exclude small birds, even without substantially reducing miner densities, due to the breakdown of social structures that are central to the species' despotic behaviour. However, this effect on small birds is unlikely to persist in the long term. Synthesis and applications: Despite evidence from other studies that direct removal of noisy miners can result in rapid and sustained conservation benefit for bird communities at small scales, our findings cast doubt on the potential to scale‐up this management approach. The circumstances under which direct control of noisy miners can be achieved remain unresolved. [ABSTRACT FROM AUTHOR]

The ecological characteristics of a species, along with small-scale landscape features are known to affect the patterns of genetic structure within populations. Due to dispersal limitation, closely-related individuals tend to be closer spatially, leading to spatial genetic structure. Physical barriers also may prevent individuals from dispersing further, and lead individuals on one side of a barrier to be more related than individuals from different sides. We tested these hypotheses by examining patterns of fine-scale spatial genetic structure within populations of three relatively sedentary Amazonian-forest understorey birds that differ in their ecological requirements. We sampled birds in a 10,000 ha reserve, covered by largely undisturbed old-growth forests and traversed by a central ridge. We found positive spatial genetic structure at short distances only for Percnostola rufifrons, a treefall-gap specialist. Positive genetic structure occurred at 6 km for Glyphorynchus spirurus, a solitary bark-forager; no spatial genetic structure was found for Gymnopithys rufigula, an army-ant follower. Individuals of none of the three species were more related on a given side of the ridgeline than between different sides but, at greater distances, there was a tendency of individuals located on opposite sides of the ridgeline to be less related than individuals located on the same side, for all species analysed. Our study indicates that local topographic features do not prevent, but likely reduce, gene flow within populations in continuous forests, and that the development of fine-scale spatial genetic structure may depend on the dispersal propensity of a species. Thus, studies of species assemblages need to account for the different ecological characteristics of the constituent species. [ABSTRACT FROM AUTHOR]

Abstract: Aim: We tested the effects of season and migratory status (residents‐versus‐seasonal migrants) on island biogeography of bird assemblages through partitioning beta diversity into richness and turnover components and community nestedness metrics. We predicted that total beta diversity, the richness component of beta diversity and community nestedness will be lower for bird assemblages in winter than in summer, and lowest of all for winter visitors. These predictions were derived from published ideas about resource availability, movement and habitat choice in birds in different seasons. Location: Thousand Island Lake, China. Methods: Bird species were sampled using line transects on 36 islands during five breeding and winter seasons (2009−2014). Birds were grouped into assemblages of winter residents, winter visitors and summer residents. Associations between beta diversity partitioning, island area, isolation and habitat richness were tested using partial Mantel correlations. We complemented these tests with measures of nestedness and null model approaches. Results: Contrary to expectation, beta diversity, nestedness and difference of beta diversity or its components from null models were higher for winter residents than either summer resident or winter visitor assemblages. As predicted, winter visitors showed little association with habitat richness, and beta diversity was rarely different from null communities. Summer residents had the highest correlations of beta diversity components with habitat richness, but showed the lowest level of total beta diversity, a low richness component and were anti‐nested (less nested than random). Main conclusions: Substantial differences were found in the biogeography of winter‐versus‐summer residents, and seasonal visitor (migratory)‐versus‐resident bird assemblages, which match expectations derived from bird biology and population ecology. Summer residents highlighted the role of habitat‐related niche differences, whereas winter residents showed area‐related selective extinction. By contrast, winter visitors appeared to be more randomly distributed. [ABSTRACT FROM AUTHOR]

Australia, New Zealand, New Guinea, Wallacea, and the islands of the Pacific Ocean collectively possess 42% of the world’s parrot species, including half of all Critically Endangered species. We used comparative methods to review the factors related to extinction risk of 167 extant and 5 extinct parrot species from this region, subsequently referred to as ‘Oceania’. We tested a range of ecological and socio-economic variables as predictors of extinction risk for parrots in the region while controlling for phylogeny. Parrot species were most likely to be threatened if they had small historical ranges, large bodies, or a high dependency on forest, or if they were endemic to a single country, or native to a country with high unemployment. Our analysis identifies invasive species as an especially severe threat to the parrots of Oceania. We present maps of parrot species’ diversity and draw attention to regions of conservation concern. Our comparative analysis presents an important overview of the factors contributing to the decline of parrots in Oceania, and provides a strong basis for comparison with other parts of the world. [ABSTRACT FROM PUBLISHER]

Only three wild-bred female Orange-bellied Parrots returned from migration in the 2016/17 breeding season, representing the lowest point of a long-term decline. In this context of imminent extinction risk we (i) update knowledge of population parameters, (ii) critically evaluate current recovery actions, and (iii) identify new management options. We present new data from the 2016/17 breeding season. Orange-bellied Parrots were only observed at the last known breeding site where fire suppression may havecaused shortage of natural food. Recently burned habitat elsewhere support abundant food, but no parrots. Fecundity of captive-bred individuals was significantly worse than wild-bred individuals (0.8 vs. 3 fledglings respectively), mostly due to infertility. Bacterial septicemia due to contaminated food caused mortalities of at least four nestlings. Fostering captive-bred nestlings to the wild showed some potential as a recovery tool, with 2 of 4 nests accepting a foster nestling, and one of these fledging successfully. Captive-bred birds had poorer feather condition than wild birds. Addressing food shortages and the addition of new managementactions to improve population recruitment are critical and urgent recovery priorities. We suggest recovery priorities for the species arising from our results, including emergency intervention to prevent imminent extinction. [ABSTRACT FROM PUBLISHER]

House cats Felis catus have contributed to the extinction of many bird species on islands, but their impact on continental bird faunas is less well resolved. Here, we compile and analyse a comprehensive record of all bird species known to be killed by feral cats at a continental scale. From published studies and unpublished data, we document predation by feral and pet cats on 357 bird species in Australia, including 338 Australian (non-vagrant) native bird species (= 45.6% of the 741 Australian native bird species, excluding vagrants). This tally included 24 species listed as threatened or extinct by the IUCN (40% of the 58 non-vagrant Australian species listed as threatened), and 71 of the 117 bird species (61%) listed as threatened under Australian legislation (or species with one or more subspecies so listed). These tallies are substantially larger than reported in previous reviews. We provide the first continental-scale attempt to model bird species' traits that are associated with likelihood of being killed by cats, and use such modelling to attempt to redress some inevitable biases in compilation of predation records on birds. We conclude that the likelihood of being killed by a cat was highest for bird species that are restricted to islands, are of intermediate body mass ( ca. 60–300 g), and nest and forage on the ground, and least likely for bird species occurring mostly in rainforests and wetlands. We also identify a set of bird species most likely to be threatened by cat-predation and hence most likely to benefit from enhanced management of cats. This study does not specifically evaluate the impact of cats on bird populations or on the conservation of Australian birds, but our results suggest that such impact may be much more pervasive than previously documented. [ABSTRACT FROM AUTHOR]

Anthropogenic changes to the landscape and climate have resulted in secondary contact between previously allopatric species. This can result in genetic introgression and reverse speciation when closely related species are able to hybridize. The Golden-winged Warbler has declined or been extirpated across much of its range where it has come into secondary contact with the Blue-winged Warbler. Genetic screening previously showed that introgression had occurred range-wide with the exception of Manitoba, Canada. Our goal was to reassess the genetic status of the Golden-winged Warbler population in Manitoba and to examine the demographics and habitat use of phenotypic and genetic hybrids. From 2011 to 2014, we sampled and screened mtDNA from 205 Golden-winged Warblers and hybrids in southeast Manitoba. In 2012, we monitored all Golden-winged Warbler territories within those sites and measured territory- and landscape-level habitat variables. Of the birds screened, 195 had a phenotype that matched their mtDNA type, two were phenotypic hybrids, and eight showed a phenotypic-mtDNA mismatch (cryptic hybrids). We found no difference in the habitat used by Golden-winged Warblers compared with hybrids at either scale. The low proportion of hybrids found in Manitoba and the lack of a distinguishable difference in habitat use by Golden-winged Warblers and hybrids indicates that the exclusion of hybrid birds from Golden-winged Warbler habitat is unlikely to be a successful conservation strategy. The best way to manage for Golden-winged Warblers is to slow the habitat loss and fragmentation that continues within Manitoba and to actively manage early-successional deciduous forest using tools such as fire and logging. [ABSTRACT FROM AUTHOR]

Hawaiian honeycreepers, comprising an endemic radiation of passerine birds in the Hawaiian archipelago, have suffered losses of individual island populations and the extinction of many species as a result of colonization of the islands by Polynesians and, more recently, introduced avian pox virus and avian malaria. Here, I test the idea that populations have an intrinsic tendency toward extinction regardless of the cause. The distribution of each species before the arrival of humans in the archipelago was inferred from present distribution, historical records, and fossil remains. On the basis of these records, each species was placed in one of four stages of the taxon cycle: (1) expanding or recently expanded, (2) differentiating, (3) fragmenting, or (4) single-island endemic. Subsequent extinction of individual island populations was most frequent in stage 3 species, which had already suffered loss of individual island populations, suggesting commonality in vulnerability to extinction from anthropogenic and nonanthropogenic causes. [ABSTRACT FROM AUTHOR]

In the last two decades, unsustainable levels of wildlife trade have led to an unprecedented biological crisis. Southeast Asia has become an epicentre for wildlife trade in general and specifically for the cage-bird trade, resulting in numerous regional extinctions. To assess the impact of regional extinction on the loss of genetic diversity in affected cage-birds, we obtained > 18,000 genome-wide markers across 60 Southeast Asian samples of the white-rumped shama ( Copsychus malabaricus ), a prized songbird that has gone extinct across wide swathes of its Southeast Asian range following heavy poaching. High levels of genomic uniformity across its mainland Southeast Asian range indicate that future reintroductions of birds from regions with less poaching could help bolster populations in regions with intense poaching pressure. Genomic assignment tests demonstrate that birds in the only Sundaic country with strict enforcement of poaching bans, Singapore, are a mosaic of both native populations and escaped cage-birds of mostly peninsular Malaysian origin, indicating that inadvertent reintroductions of caged shamas have led to the recovery of a local population that was nearly extinct and now constitutes a safe haven for the subspecies tricolor . Our study underscores the potential of genome-wide SNPs in identifying implications of trade on wildlife populations. [ABSTRACT FROM AUTHOR]

Biodiversity conservation projects confront immediate and escalating threats with limited funding. Conservation theory suggests that the best response to the species extinction crisis is to spend money as soon as it becomes available, and this is often an explicit constraint placed on funding. We use a general dynamic model of a conservation landscape to show that this decision to "front-load" project spending can be suboptimal if a delay allows managers to use resources more strategically. Our model demonstrates the existence of temporal efficiencies in conservation management, which parallel the spatial efficiencies identified by systematic conservation planning. The optimal timing of decisions balances the rate of biodiversity decline (e.g., the relaxation of extinction debts, or the progress of climate change) against the rate at which spending appreciates in value (e.g., through interest, learning, or capacity building). We contrast the benefits of acting and waiting in two ecosystems where restoration can mitigate forest bird extinction debts: South Australia's Mount Lofty Ranges and Paraguay's Atlantic Forest. In both cases, conservation outcomes cannot be maximized by front-loading spending, and the optimal solution recommends substantial delays before managers undertake conservation actions. Surprisingly, these delays allow superior conservation benefits to be achieved, in less time than frontloading. Our analyses provide an intuitive and mechanistic rationale for strategic delay, which contrasts with the orthodoxy of frontloaded spending for conservation actions. Our results illustrate the conservation efficiencies that could be achieved if decision makers choose when to spend their limited resources, as opposed to just where to spend them. [ABSTRACT FROM AUTHOR]

Long-term population decline of the little owl has been recorded in Western Europe and available evidence also suggests severe range restriction in many Central European regions. Using two nationwide volunteer-based monitoring programmes during the years 2009-2016, we investigated distribution, population density and breeding associations of the little owl in the Czech Republic and Slovakia. Across the two countries combined, the average population density of the little owl was 0.19 calling males/10 km². However, the population density was markedly higher in Slovakia (0.36 calling males/10 km²) than in the Czech Republic (0.09 calling males/10 km²). The overall breeding population of the little owl was estimated at 130 breeding pairs in the Czech Republic and 550 in Slovakia. Compared to the situation two decades ago, those estimates represented a 87-94 % decline in the breeding population in the Czech Republic and a 31-45 % reduction in Slovakia. Our data also revealed marked distributional range contraction of the little owl, indicating rapid local extinctions over the last two decades. The analysis of expected breeding places of the little owl confirmed a strong preference for man-made objects over the original breeding sites in tree cavities. In the light of our present results, we propose urgent preparation and implementation of a species action plan with conservation measures to halt the little owl's steep decline in Central Europe. [ABSTRACT FROM AUTHOR]

The Collared Pratincole (Glareola pratincola), which was once a typical breeding species of the sodic grasslands of the Great Plain, has become threatened with extinction from Hungary. It disappeared from the traditional grassland breeding sites before the 2000 and is currently breeding only in three sites in agricultural environments in Hungary. The objectives of our research were to find links between the use of shallow wetlands and the breeding behaviour of the species and to identify the characteristics of its breeding on ploughed fields. Data were collected between 2008 and 2016 as part of preparations for the conservation of the largest population which is found in the Nagykunság. We found a positive correlation between colony size and the area of the nearby wetland. We calculated the proportion of habitat-types used for nesting, and found that cultivated fields and fallow lands were the most important. Additionally, we also found that colony sizes were substantially smaller during the research period than those found earlier in the traditional grassland habitats. Finally, we found a positive trend in the size of the population during the research period. [ABSTRACT FROM AUTHOR]

Reintroductions have been increasingly used for species restoration and it seems that this conservation tool is going to be more used in the future. Nevertheless, there is not a clear consensus about the better procedure for that, consequently a better knowledge of how to optimize this kind of management is needed. Here we examined the dynamics of released long-lived bird populations (lesser kestrel, Falco naumanni, Bonelli's eagle Aquila fasciata, and bearded vulture Gypaetus barbatus) in object-oriented simulated reintroduction programs. To do that, number of young per year and number of years of released necessary to achieve a successful reintroduced population were calculated. We define a successful reintroduction as one in which when the probability of extinction during two times the maximum live-span period for the species (20, 50, and 64 years respectively) was less than 0.001 (P<0.001) and they showed a positive trend in population size (r>0.00). Results showed that a similar total number of young (mean 98.33±5.26) must be released in all the species in all the scenarios in order to get a successful reintroduction. Consequently, as more young per year are released the new population is going to be larger at the end of the simulations, the lesser the negative effects in the donor population and the lowest the total budget needed will be. [ABSTRACT FROM AUTHOR]

Sobral et al. (Ecology Letters, 19, 2016, 1091) reported that the loss of bird functional and phylogenetic diversity due to species extinctions was not compensated by exotic species introductions. Here, we demonstrate that the reported changes in biodiversity were underestimated because of methodological pitfalls. [ABSTRACT FROM AUTHOR]

South African coastal forests form part of two critically endangered eco-regions and harbor an extinction debt. Remaining fragments are small, isolated, and embedded within a range of human land-use types. In this study, we ask: how should we invest conservation resources if we want to restore this landscape and prevent predicted extinctions? To answer this question, we use path analyses to determine the direct and indirect effects of forest area, forest connectivity, and matrix land-use types on species richness within five bird feeding guilds. We found that forest connectivity had a significant direct effect on insectivores-fragments that were more connected had more species of insectivores than those that were isolated. Moreover, forest area had a significant indirect effect on insectivores that was mediated through tree species richness. Larger fragments had more species of trees, which led to more species of insectivores. Fragment area, connectivity, matrix land-use type, and tree species richness had no significant effects on the species richness of frugivores, nectarivores, granivores, or generalist feeders. To conserve insectivores in coastal forests, conservation efforts should focus on maximizing fragment connectivity across the landscape, but also protect the tree community within fragments from degradation. This can be achieved by including matrix habitats that adjoin forest fragments within forest conservation and restoration plans. Natural matrix habitats can increase connectivity, provide supplementary resources, buffer fragments from degradation, and could play an important role in safeguarding diversity and preventing extinctions in this threatened human-modified landscape. [ABSTRACT FROM AUTHOR]

Background: The objective of the present study was to compare both the acquisition speed and the resistance to extinction of a simple discrimination in pigeons, depending on whether the reinforcing consequence included different conditioned reinforcer stimuli or always the same. Method: The study was conducted with four experimentally naive female pigeons, which were trained to respond to a "go-no go" procedure in four Skinner boxes with coupled touchscreens. The subjects were divided into two conditions with two subjects each. In the Experimental condition, the reinforcement of correct trials was performed by the presentation of one of four previously trained conditioned reinforcers followed by food, while in the Control condition the conditioned reinforcer stimulus was always the same. After acquiring the discrimination, all the subjects were exposed to the extinction phase. Results: The subjects of the Experimental condition needed about half of the sessions that the subjects of the Control condition needed to acquire the discrimination. In addition, subjects of the Experimental condition continued responding for more sessions than Control subjects in the extinction phase, although there were no differences in the resistance to extinction. Conclusions: Acquisition speed is greater when a variety of conditioned reinforcers is applied. [ABSTRACT FROM AUTHOR]

Questions Following the mid 15th century AD extinction of moa (Aves: Dinornithiformes) there was a ~400-yr period when large herbivores were absent from New Zealand's terrestrial ecosystems. This ended with the introduction of mammalian herbivores by European settlers in the 19th century. For at least 40 yr researchers have speculated about how New Zealand's vegetation communities might have responded to the 'herbivore gap'. Did plant taxa once consumed by moa flourish in forest understoreys without large herbivores to browse them? Did forest understoreys become denser, preventing regeneration of long-lived conifers and altering forest composition? Such questions remain to be tested using palaeoecological records. Location Three locations on South Island, New Zealand (from <20 to 750 m a.s.l) where forest has not been burned since human settlement, and where there has been no obvious geological or climatic disturbance events over the past 1000 yr that have influenced vegetation dynamics. Methods We identified and quantified pollen grains and fern spores from soil/peat cores taken beneath, or adjacent to, tall forest canopies. Soil/peat samples from the cores were radiocarbon dated and Bayesian age-depth models were constructed for each core, from which depths corresponding to the herbivore gap period were identified. Changes in pollen/spore abundances occurring within the herbivore gap were identified and critically examined for consistency between cores and likelihood of being caused by loss of browsing pressure from large herbivores (through comparison with plant taxa known to have been consumed by moa). Results Ground fern spores and Coprosma pollen exhibited increases in relative abundance at all three sites during the herbivore gap. Both occur frequently in moa coprolites and gizzard content, and so can be interpreted as possible responses to moa extinction. However, other changes in pollen assemblages at this time were inconsistent between sites, or could be better explained as being related to anthropogenic burning in the local region. Conclusions New Zealand forest plant communities appear to have experienced only relatively minor changes during the herbivore gap. Our results contradict long-standing hypotheses that shrubs and ferns had flourished in New Zealand forest understoreys at this time, preventing podocarp regeneration. However, due to the relatively recent extinction of moa, and long life span of many forest trees, there may be an extinction debt where the long-term consequences of moa extinction are still to be fully realized. [ABSTRACT FROM AUTHOR]