China makes a unique and vital contribution to maintaining global and regional waterbird diversity and conservation. Despite considerable historical conservation efforts, the continued loss of waterbird diversity and abundance necessitates a contemporary review of Chinese sites of conservation significance. The Ecological Protection Red Line (EPRL) was proposed by China’s Central Government in 2013 to protect areas providing crucial ecosystem services and provides the opportunity for such a review to enhance waterbird conservation in China. By incorporating various sources of data, surveys and information, we identified a suite of sites of waterbird conservation significance in China, following the Ramsar Site Criteria/Important Bird and Biodiversity Area (IBA) Criteria. In total, we identified 422 sites, of which the existing 286 IBA sites formed the basis of the site safeguard network. Altogether, these sites of waterbird conservation significance constitute over 727,000 km2 (7.6% of China’s land surface). Over half of the area of these sites is outside China’s national nature reserves, thus confirming the importance and urgency of including them in the EPRL for the effective conservation of waterbird sites. We suggest that this assessment of sites of waterbird importance offers a useful model to apply to other taxa, such as terrestrial birds and mammals.

The Yellow Sea region is of high global importance for waterbird populations, but recent systematic bird count data enabling identification of the most important sites are relatively sparse for some areas. Surveys of waterbirds at three sites on the coast of southern Jiangsu Province, China, in 2014 and 2015 produced peak counts of international importance for 24 species, including seven globally threatened and six Near Threatened species. The area is of particular global importance for the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea (peak count across all three study sites: 62 in spring [2015] and 225 in autumn [2014] and ‘Endangered’ Spotted Greenshank Tringa guttifer (peak count across all three study sites: 210 in spring [2014] and 1,110 in autumn [2015]). The southern Jiangsu coast is therefore currently the most important migratory stopover area in the world, in both spring and autumn, for both species. Several serious and acute threats to waterbirds were recorded at these study sites. Paramount is the threat of large-scale land claim which would completely destroy intertidal mudflats of critical importance to waterbirds. Degradation of intertidal mudflat habitats through the spread of invasive Spartina, and mortality of waterbirds by entrapment in nets or deliberate poisoning are also real and present serious threats here. Collisions with, and displacement by, wind turbines and other structures, and industrial chemical pollution may represent additional potential threats. We recommend the rapid establishment of effective protected areas for waterbirds in the study area, maintaining large areas of open intertidal mudflat, and the urgent removal of all serious threats currently faced by waterbirds here.

São Tomé holds 20 endemic bird species, including the little known and ‘Critically Endangered’ Dwarf Olive Ibis Bostrychia bocagei, São Tomé Fiscal Lanius newtoni and São Tomé Grosbeak Neospiza concolor. We conducted a systematic survey of the core forest area, performing 1,680 point counts and compiling occasional observations, which enabled the identification of new areas of occurrence for the target species. MaxEnt distribution modelling suggested that the ibis and fiscal have roughly half of the potential area of occurrence that had been assumed (127 and 117 km2, respectively), while it more than doubled that of the grosbeak (187 km2). The south-west central region of the island, most of which is included in the São Tomé Obô Natural Park, has the highest potential for the Critically Endangered birds. We confirmed the association of all target species with native forest. The ibis preferred high tree density, while the fiscal selected low tree density and intermediate altitudes. Despite very restricted ranges, population sizes seem to be larger than previously assumed. These results suggest that the fiscal and grosbeak might be better classified as ‘Endangered’, while the ibis should maintain its status under different criteria, due to a very restricted range during the breeding season. This work provides vital ecological knowledge to support conservation action focusing on these species and their habitats, highlighting the need to improve the effectiveness of the São Tomé Obô Natural Park in protecting its unique biodiversity.

The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.

The Amami Thrush, Zoothera dauma major, is an endemic subspecies of the Eurasian Scaly Thrush that is distributed only on Amami-Oshima Island in south-western Japan. This bird was formerly considered to be a distinct species (Z. major) and was listed on the IUCN Red List as ‘Critically Endangered’ based on the small population size estimated in the early 2000s. To re-evaluate the conservation status of this bird, we estimated the number of singing males from song-count surveys conducted by an NPO with public participation from 2007 to 2013. An estimation that applied a distance sampling method revealed the number of singing males to be 945–1,858 up to 2012. A sudden increase in song counts was recorded in 2013, and the estimate increased to 2,512 in 2013. Based on the assumption that the sex ratio does not deviate from 1:1, simply doubling the number was considered to produce the estimated population size (number of males and females that are capable of breeding). The present study also confirmed that the Amami Thrush was more abundant in older forest with less open habitat, suggesting that forest maturity is an important factor for thrush abundance. The relative density of the invasive small Indian mongoose Herpestes auropunctatus probably affected thrush abundance before the early 2010s prior to mongoose eradication efforts. Our results suggest that thrush recovery was likely associated with forest regeneration and mongoose eradication. However, it is important to continue population monitoring approaches including public participation to promote further conservation of the Amami Thrush.

The robust assessment of conservation status increasingly requires population metrics for species that may be little-researched, with no prospect of immediate improvement, but for which citizen science atlas data may exist. We explore the potential for bird atlas data to generate population metrics of use in red data assessment, using the endemic and near-endemic birds of southern Africa. This region, defined here as South Africa, Lesotho and Swaziland, is home to a large number of endemic bird species and an active atlas project. The Southern African Bird Atlas Projects (SABAP) 1 and 2 are large-scale citizen science data sets, consisting of hundreds of thousands of bird checklists and > 10 million bird occurrence records on a grid across the subcontinent. These data contain detailed information on species’ distributions and population change. For conservationists, metrics that guide decisions on the conservation status of a species for red listing can be obtained from SABAP, including range size, range change, population change, and range connectivity (fragmentation). We present a range of conservation metrics for these bird species, focusing on population change metrics together with an associated statistical confidence metric. Population change metrics correlate with change metrics calculated from dynamic occupancy modelling for a set of 191 common species. We identify four species with neither international nor local threatened status, yet for which bird atlas data suggest alarming declines, and two species with threatened status for which our metrics suggest could be reconsidered. A standardised approach to deciding the conservation status of a species is useful so that charismatic or flagship species do not receive disproportionate attention, although ultimately conservation status of any species must always be a consultative process.

The middle and lower Yangtze River floodplain is a globally important wintering area for waterbirds in the East Asian-Australasian Flyway. Ornithologists have reported on wintering waterbirds in the floodplain since the 1950s. However, an integrated analysis of the long-term changes in waterbird diversity is not available. Here, we synthesise existing information on changes in wintering waterbird abundance and distribution in the floodplain, summarise possible influencing factors and propose some priorities for further research. Waterbird richness and abundance have declined over the past 60 years. Declining trends have been observed in a number of areas and species. Nevertheless, a few areas and species showed different trends. In addition, waterbirds have become more concentrated in a few suitable areas such as Poyang Lake and Dongting Lake. Land reclamation, hunting, dam operation and extensive aquaculture are probably the four major threats to wintering waterbirds, while establishment of nature reserves is beneficial to waterbird conservation. Our study suggests that waterbirds in the floodplain are vulnerable, and that effective conservation measures are needed to protect and restore the waterbird diversity of this area.

Forest ecosystems in South Africa are at risk from a variety of anthropogenic threats impacting the faunal species dependent on them. These impacts often differ depending on species-specific characteristics. Range data on forest dependent bird species from the South African Bird Atlas Project (SABAP1 and SABAP2) were analysed to determine links between deforestation, species characteristics and range declines. Half of the species studied were found to have declining ranges. Range change data for these species were correlated with data on changes in land cover from 1990 to 2014. To determine which land cover changes affect extinction, occupancy was modelled for 30 sites across South Africa which experienced a loss of more than 10 species. Most species lost were birds of prey or insectivores. Indigenous forest decreased in 17% (n = 5) sites, while plantations/woodlots decreased in 60% (n = 18) sites. Occupancy modelling showed extinction to be mitigated by plantations in 6/28 species, and forest expansion mitigated extinction in 7/28 species. Responses to deforestation did not appear to be related to particular species characteristics. Half of South Africa’s forest-dependent bird species have declining ranges, with the loss of these species most prominent in the Eastern Cape province. Four responses to changes in forest and plantation cover are discussed: direct effects, with forest loss causing species loss; matrix effects, where plantation loss resulted in species loss; degradation of indigenous forest; and the advent of new forest arising from woody thickening caused by carbon fertilisation, which may not result in optimal habitat for forest-dependent birds.

Mountain systems are often recognised as biodiversity hotspots; however, most montane forests are human-modified. Understanding the conservation value of human-modified forests is essential to mountain biodiversity conservation. In this study, mist-nets and point-counts were used to compare the bird communities of primary forests on ridges in the Ailao Mountains of Yunnan, China, and secondary forests, firewood forests, and pine plantations in nearby lower elevation zones. We found that community turnover among habitats was very high using both methods. Although the percentage of forest interior species and insectivores in each habitat was higher in the primary forests than in the human-modified forests, relatively high percentages of forest interior species and insectivores were recorded in the human-modified forests. Moreover, many bird species, forest interior species, insectivores and babblers were only recorded in the human-modified forests. Our study indicated that the primary forests are important for sustaining mountain bird diversity. However, given that primary forests are restricted to ridges, secondary forests, firewood forests, and pine plantations at lower elevations also play important roles in bird conservation in mountainous regions by increasing landscape diversity and partially offsetting species loss from primary forests. Therefore, conservation efforts should also be concentrated on human-modified forests at lower elevations in mountainous regions in south-west China.

Populations of several long-distance migratory songbirds in Eurasia are in peril, drastically illustrated by the recent range-wide population collapse in the Yellow-breasted Bunting Emberiza aureola. There are signals of a strong decline also in the Rustic Bunting E. rustica, but no range-wide assessment of population trends in this superabundant and widespread bunting species has yet been undertaken. The conservation status of Rustic Bunting is ‘Least Concern’ on the global IUCN Red List, but it has recently been upgraded to ‘Vulnerable’ on the European Red List. To assess the Rustic Bunting’s global conservation status we compiled, for the first time, population data across its breeding and wintering ranges. The analysis reveals a 75–87% decline in overall population size over the last 30 years and a 32–91% decline over the last 10 years. The trend estimates indicate that the long-term (30-year) range-wide population decline in the Rustic Bunting is of similar magnitude to two well-known examples of declining species within the same genus, the Yellow-breasted Bunting and the Ortolan Bunting E. hortulana. The magnitude of the range-wide population decline over the last 10 years suggests that the Rustic Bunting could be upgraded from ‘Least Concern’ to ‘Vulnerable’ or ‘Endangered’ on the IUCN global Red List. Agricultural intensification in the wintering range and intensified levels of disturbance, including logging and fire, in the breeding range could be important drivers of the range-wide population decline, and persecution could also contribute. Untangling threat factors and their interactions on Rustic Bunting is necessary for conservation, but hampered by our currently limited understanding of the relationships between population dynamics and different threats.

DNA barcoding has become a widely used and valuable tool in taxonomic research during the past three decades and its application is expanding to fields such as wildlife forensics (e.g. anti-poaching actions). One of the major advantages of DNA barcoding is that it allows for species identification from largely incomplete, deformed or cooked samples and even from traces of biological material. Cyprus is a well-known biodiversity hotspot, the island avifauna comprising around 400 species, 117 of which are listed in Annex I of the Birds Directive (2009/147/EC). Each year on average, 2.3 million individuals (mainly small migratory birds) are trapped illegally on the island and often served at restaurants. Consequently, reliable identification of specimens from processed tissues can be crucial for undertaking legal actions. Herein DNA barcoding of the large majority of bird species resident in Cyprus plus several migrants that were illegally captured was carried out to support local authorities in their anti-poaching actions. In this study, tissue from 103 specimens representing 81 bird taxa were sampled and a 648-bp long fragment of the Cytochrome Oxidase subunit Ι (COI) gene was targeted using a combination of standard, nested and semi-nested PCR depending on the condition of the tissue at hand. Sequences were obtained from all investigated samples and a total of 92 haplotypes was recovered. Phylogenetic reconstructions returned a pattern of relationships among taxa largely compatible with known avian phylogeny. Furthermore, diagnostic polymorphisms within the genus including one of the main targeted species, Sylvia atricapilla, were found. In conclusion, an avian genetic dataset is now available for the law enforcement authorities to identify specimens either confiscated (even when morphologically deformed or cooked) during raids in restaurants and in other premises suspected of serving illegally protected bird species or from trappers.

Direct payments to communities or individuals have gained traction as a tool for species conservation; however, few studies have evaluated their effectiveness. From 2010 to 2014, we monitored nests and implemented a direct payment nest protection programme for six sandbar-nesting bird species on the Mekong River, Cambodia, and tested if nest protection improved reproductive success. Nests were guarded by community members; additionally, exclosures were used to protect nests of River Tern Sterna aurantia, the species of highest conservation concern. We investigated factors affecting nest and chick survival, and probability of nest failure due to egg harvest or predation. Nesting later in the season generally resulted in lower nest and chick survival. Nest protection improved survival rates of River Tern nests and chicks, and Small Pratincole Glareola lactea nests. River Tern nest success was 60% for exclosed (and guarded) nests, 29% for guarded (but unexclosed) nests, and 5% for unprotected nests. River Tern fledging success was 82% for exclosed chicks, 40% for chicks that were guarded only, and 2% for unprotected chicks. Small Pratincole nest success was 21% for guarded and 6% for unguarded nests. Egg harvest by humans was lower among protected nests and declined during the study. Nest predation by animals increased during the study despite nest guarding; however, predator exclosures effectively protected nests and chicks. Additional predator control measures could further improve reproductive success of sandbar-nesting birds. Overall, nest protection involving direct payments was highly effective, but required diligent use of nest exclosures, frequent monitoring, and strong community relationships.

The Fennoscandian population of the Lesser White-fronted Goose Anser erythropus (LWfG) is on the verge of extinction and migrates from northern Fennoscandia to Greece on a regular seasonal basis. For the first time, diet selection was investigated during two years at Kerkini Lake, a wintering site in Greece. The relative use of LWfG’s feeding habitats was systematically recorded by visual observations of the LWfG flocks. Food availability was measured by the relative cover of available vegetation types while the diet composition was determined by the microhistological analysis of droppings. In addition, we determined crude protein, neutral detergent fibre, acid detergent fibre and acid detergent lignin content of the most preferred plant species by LWfG and all vegetation categories that contributed to LWfG diet in the middle of the duration of their stay at Kerkini Lake and after their departure from the lake. LWfG feeding habitat was exclusively marshy grassland in water less than 5 cm deep up to 300–400 m away from the shore. LWfG selected a diverse number of plant species (33), however, grass made up the 58% of their diets. The most preferred plant species were Echinochloa crus-galli, Cyperus esculentus, Scirpus lacustris and Ranunculus sceleratus. LWfG departed from Kerkini Lake in mid-December to the Evros Delta (Thrace, eastern Greece), when either food availability falls in very low levels or flooding occurred in their main feeding habitat. Consequently, as long as food and habitat resources are available for LWfG, it is very likely that the birds will winter mainly at Kerkini Lake and not at the Evros Delta, which will contribute to further minimisation of the theoretical risk of accidental shooting of LWfG at the latter wintering habitat. Thus, future conservation actions should primarily focus on the grassland improvement at Kerkini Lake enhancing the availability of food resources for LWfG (mainly grasses) and the protection of the feeding habitat from flooding.

Post-fledging survival plays a vital role in the dynamics of bird populations and yet is the least-studied avian life-stage. Habitat requirements post-fledging may have important implications for behaviour and survival, especially for declining populations in landscapes that have undergone wide-scale anthropogenic modification, resulting in an altered distribution and composition of habitats. The European Turtle Dove is a widespread but rapidly declining species both within the UK and across Europe. Reduced seed food availability is thought to influence breeding success of this species, but it is not known whether post-fledging survival may also be influenced by seed availability. Here, we use leg-ring radio-tag attachments to monitor post-fledging survival and movements in 15 Turtle Dove nestlings from eight nests monitored during 2014 as part of a wider autecological study. Fledglings remained in close proximity to their nest for three weeks post-tagging, spending more than half their time in the immediate vicinity (within ∼20 m) of the nest. 95% of foraging trips during this period were within 329 m of the nest and fledglings selected seed-rich habitat (semi-natural grassland, low-intensity grazing, fallow and quarries). Fledglings that were heavier and in better body condition at seven days old were more likely to survive for 30 days post-fledging, and the proportion of available seed-rich habitat was a strong predictor of nestling weight and condition at seven days old. Whilst our sample size is modest, this study highlights the crucial role of food availability in juvenile survival, both while adults are feeding nestlings, and to recently fledged young, and the potential for agri-environment schemes providing foraging and nesting habitats in close proximity to provide important benefits.

Following an abnormal flood in 2010 at China’s Poyang Lake, we observed wintering Siberian Cranes Leucogeranus leucogeranus switch from foraging in the shallow-water wetlands they typically use to grassland habitats. These previously undocumented habitat selection patterns raised questions whether differences in crane behaviour such as foraging success existed between the two habitats and how those differences might affect this critically endangered species. Over two winters, we used the density of customary food items (tubers of Vallisneria spp.) obtained from long-term monitoring efforts, Siberian Cranes flock behaviours, individual foraging success and estimated total flock foraging effort across both habitats. Novel foraging patterns by Siberian Cranes were associated with low densities of Vallisneria tubers across multiple sub-lakes within Poyang Lake National Nature Reserve (PLNR). Foraging success was higher in grasslands than in wetlands in winter 2010–2011, but higher in wetlands following a recovery of Vallisneria in 2011–2012. Subsequent to upland foraging during the winter of 2010–2011, we observed lower juvenile to adult ratio of Siberian Cranes at a fall migratory stopover location in north-eastern China despite indications of average environmental conditions in the nesting areas from 2010 to 2012. While grasslands adjacent to shallow-water habitats may be important refugia for wintering Siberian Cranes when Vallisneria is absent or inaccessible, and should be included in protected areas, multi-year dependence on grasslands for foraging could negatively impact population levels. Eliminating crab farming in protected areas and extending protection to shallow water areas sheltered from flooding by dykes could also help secure high quality foraging habitat under a variety of hydrological regimes. Novel foraging patterns by wintering Siberian Cranes represent a new challenge to the conservation efforts for this species that focus on shallow-water wetlands, and may be indicative of broader changes within Poyang’s ecosystem.

Birders are generally nature-oriented; however, their understanding of key bird conservation issues remains under-examined. We surveyed English-speaking birders online and face-to-face, asking questions related to their views on conservation, conservation funding and their understanding of a global bird conservation programme (BirdLife International’s Important Bird and Biodiversity Areas [IBAs]). Most birders who responded to the survey were from Australia, the United Kingdom, South Africa and the USA. Birders tend to value bird conservation in an ecocentric way, often citing the overarching importance of general biodiversity. The ecological roles that birds play were also highlighted, but this varied across socio-demographic groups. Despite their positive support for conservation, less than half of all birders surveyed were familiar with the IBA programme. Familiarity with IBAs was driven by socio-demographic factors, with males more familiar than females and South African birders more familiar than birders from Australia and the United Kingdom. Most birders are willing to make contributions to bird conservation when visiting key birding sites, however they also feel governments should remain the main funders of conservation. Opportunities to enhance engagement between birders and bird conservation groups exist with most indicating a desire to learn more about bird conservation at birding sites. Increasing access to relevant information and presenting opportunities to contribute to conservation at birding sites could provide tangible benefits for bird habitats, protected areas and bird conservation groups.

The use of forest habitats and migratory patterns are still unclear for tropical birds. Some are described herein for the Pantanal wetlands of Brazil. Thus, our aim was to describe different patterns of forest habitat use by birds and classify the birds’ migration patterns for the northern Pantanal region, Brazil. From September 1999 to December 2003, we sampled four forest types, during which we collected standardised data with mist-net captures and point counts, with additional ad lib. observations. We recorded 214 bird species: 113 (52.8%) were total habitat generalists; 41 (19.2%) were forest generalists; 19 (8.9%) were flooded habitat specialists; and 28 (13.1%) were not classified due to the low number of records; three other categories of habitat use divide the remaining 6% of records. About half of the species showed some migratory behaviour, these were classified by us according to the season they spent in the area: 121 species (56.5%) as residents, 28 (13.1%) as run-off and dry migrants, 11 (5.1%) as run-off (winter) migrants, eight (3.7%) as dry (breeding) migrants, eight (3.7%) as dry and flooding (summer) migrants, eight (3.7%) as flooding migrants, three (1.4%) as flooding and run-off migrants, and 27 (12.6%) as uncommon. We constructed community occupancy models with six of the eight patterns of migration described; flooding migrants and run-off migrants were not modelled since the few species recorded also had very few detections. As expected, the model confirmed that species from all six tested migration patterns arrive and depart from the Pantanal across the seasons. Contrary to most Neotropical forests, there was a high percentage (43.5%) of non-resident species. The results show the need of investing heavily in preserving different landscape units within the Pantanal, but also in the surrounding Cerrado region, in order to conserve resident and short distance intra-tropical migrants.

Habitat selection has fundamental implications for species conservation, and in birds is often regarded as a multi-scale process. We investigated (under an information-theoretic approach) habitat selection by Woodchat Shrike Lanius senator in Italy (one of the most severely declining species in central and western Europe), considering five main types of potential determinants of shrike occurrence at the territory scale (1 ha): general structure (coarse landscape), woody vegetation, grassland habitats/bare ground, herbaceous crops, and management variables. The best supported models for species occurrence were those including general structure and woody vegetation traits. Variation partitioning suggested that overall, landscape general structure and woody vegetation explained the highest variation in shrike occurrence, and management the lowest. However, considering variation explained by only a single level, all levels performed nearly equally, but general structure did not explain an exclusive proportion of variation. A multi-level analysis suggested that shrike occurrence was eventually associated with specific habitat traits: isolated trees, shrubland and (secondarily) olive groves (all with positive effects), and dirt roads (negative effect). The most parsimonious multi-level models included only variables from woody vegetation and management traits, suggesting that the likely true determinants of species occurrence are highly specific and fine-scale habitat traits, consistent with variation partitioning. Woodchat Shrikes inhabit semi-open landscapes, within which they are attracted to shrubland and isolated trees (secondarily to olive groves) and avoid dirt roads. Suitable habitat conditions for the species depend on a trade-off between abandonment and intensive farming, and rural development programmes may be crucial for the conservation (or loss) of such conditions.

Recent studies have highlighted the threat that climate change poses to species, as areas of climatic suitability contract or shift across the landscape. North American Neotropical long-distant migrant bird species present a unique problem compared to sedentary species because climate change may differ significantly across their breeding and wintering grounds. Studying the potential future distributions of these birds is challenging on many levels, including the fact that our understanding of the wintering grounds of these species is quite poor. To address this issue, we analyse available eBird data during the winter season in the Western Hemisphere in an effort to further promote and direct citizen science efforts to focus on areas that are climatically undersampled. We used Mobility-Oriented Parity (MOP) to understand the areas where climates are most dissimilar from climates sampled by existing eBird checklists, creating a map that ranks the western hemisphere at a 10 km resolution for climatic sampling during the winter season. We found that parts of Mexico and Central America, areas of Colombia, almost the entire Amazon Basin, coastal Peru and Chile, and northern Argentina are climatically undersampled. As a test case, we then used the map of survey priorities to simulate additional sampling in Colombia and recalculated the rankings. Guiding additional sampling with the priorities reduced climate dissimilarities between sampled and unsampled grid cells more than when additional sampling expanded in proportion to current sampling efforts or based on geographic undersampling. Analyses of sampling coverage in environmental space, such as this, will be a useful tool for targeting monitoring effort for bird species.