The Royal Society for the Protection of Birds

Wilkins’s Finch Nesospiza wilkinsi is endemic to Nightingale Island (2.5 km ² ), Tristan da Cunha. It feeds on the woody fruits of the Island Tree Phylica arborea and in 2017 had a population of 120 breeding pairs. In 2021 it was uplisted from “Endangered” to “Critically Endangered” following damage to P. arborea woodland during severe storms in 2019. During a brief visit to Nightingale in February 2024, we confirmed that the finch population in the area of storm-damaged woodland has decreased by up to 75%, but the density in other areas was similar to that prior to 2019. Extrapolating from the 2017 survey, we estimated the current population to be 60–90 breeding pairs. Surveys of P. arborea structure in the storm-affected area indicated that some large trees had survived, despite being flattened, that recruitment of new trees is occurring, and that fruit loads on surviving trees are similar to those in 2017. Satellite imagery from 2005 showed similar woodland loss during another severe storm in 2001 to that experienced in 2019, indicating that the finch has survived similar events in the past. Coupled with the successful release of a biological control agent to limit the impact of the introduced brown soft scale Coccus hesperidum on Phylica fruit production, the future prospect for Wilkins’s Finch is less bleak than previously thought. However, the risk that global warming is increasing the frequency of severe storms remains a concern. Planting more woodland patches in sheltered areas would help to offset future storm damage.

The southern oceans are home to a large variety of organisms, including many endemic species. High levels of endemism are due in part to non-physical barriers limiting gene flow in marine species. The sooty albatross Phoebetria fusca is an endangered seabird breeding on seven island groups in Atlantic and Indian Oceans. We sequenced the mitochondrial control region (55 birds) and genotyped 10 microsatellite markers (88 birds) to examine the population genetics of sooty albatrosses from Tristan da Cunha and Gough Island (Atlantic Ocean), and Marion Island, Île de la Possession (Crozet) and Amsterdam Island (Indian Ocean), which together support > 99% of the global population. We also analysed the bill sulcus colouration and quantified stable isotope composition of body feathers of breeding adults from Gough and Marion Islands. Both genetic markers identified two clusters separating sooty albatrosses breeding in the Atlantic and Indian Ocean basins. Standardized colour analysis also separated populations in the two ocean basins and revealed the sulcus of sooty albatrosses on Gough Island is significantly more yellow than individuals on Marion Island. Stable isotope analysis of body feathers showed significantly higher δ¹³C values from Marion sooty albatrosses compared to Gough conspecifics, indicating different moulting areas. Sooty albatrosses breeding on islands in the two ocean basins differ from each other in their genetics, morphology and ecological preferences. Accordingly, it is recommended that separate conservation management plans be implemented for sooty albatrosses breeding in each ocean basin to prevent the loss of evolutionarily significant units.

Large-scale climatic fluctuations, such as the El Niño–Southern Oscillation, can have dramatic effects on ocean ecosystem productivity. Many mobile species breeding in temperate or higher latitudes escape the extremes of seasonal climate variation through long-distance, even trans-global migration, but how they deal with, or are affected by, such longer phased climate fluctuations is less understood. To investigate how a long-lived migratory species might respond to such periodic environmental change we collected and analysed a 13 year biologging dataset for a trans-equatorial migrant, the Manx shearwater (Puffinus puffinus). Our primary finding was that in El Niño years, non-breeding birds were at more northerly (lower) latitudes than in La Niña years, a response attributable to individual flexibility in migratory destinations. Daily time spent foraging varied in concert with this latitudinal shift, with birds foraging less in El Niño years. Secondarily, we found that in subsequent breeding, a hemisphere away, El Niño years saw a reduction in foraging time and chick provisioning rates: effects that could not be attributed to conditions at their breeding grounds in the North Atlantic. Thus, in a highly migratory animal, individuals may adjust to fluctuating non-breeding conditions but still experience cascading carry over effects on subsequent behaviour.

The density of wood is a key indicator of the carbon investment strategies of trees, impacting productivity and carbon storage. Despite its importance, the global variation in wood density and its environmental controls remain poorly understood, preventing accurate predictions of global forest carbon stocks. Here we analyse information from 1.1 million forest inventory plots alongside wood density data from 10,703 tree species to create a spatially explicit understanding of the global wood density distribution and its drivers. Our findings reveal a pronounced latitudinal gradient, with wood in tropical forests being up to 30% denser than that in boreal forests. In both angiosperms and gymnosperms, hydrothermal conditions represented by annual mean temperature and soil moisture emerged as the primary factors influencing the variation in wood density globally. This indicates similar environmental filters and evolutionary adaptations among distinct plant groups, underscoring the essential role of abiotic factors in determining wood density in forest ecosystems. Additionally, our study highlights the prominent role of disturbance, such as human modification and fire risk, in influencing wood density at more local scales. Factoring in the spatial variation of wood density notably changes the estimates of forest carbon stocks, leading to differences of up to 21% within biomes. Therefore, our research contributes to a deeper understanding of terrestrial biomass distribution and how environmental changes and disturbances impact forest ecosystems.

The incidental capture (bycatch) of seabirds is a global conservation issue and a top threat to European species that demands urgent conservation and management action. Here, we present the first European review of seabird bycatch data, considering all fishing gears and data collection methods available in the region. We calculate seabird bycatch numbers per species, family, country and European marine region and assess the reliability of the data available. The cumulative bycatch estimate extracted from this review suggests that about 195,000 seabirds (ranging from around 130,000 to 380,000) are bycaught in European waters annually. The most affected seabird species is the Common Guillemot Uria aalge with over 31,000 birds killed per year. The marine region with the highest bycatch estimate is the Northeast Atlantic (over 115,000 seabirds year⁻¹). Gillnet fisheries are responsible for the highest bycatch levels, with over 95,000 seabirds year⁻¹, followed by longline fisheries. The families most affected by bycatch are Anatidae and Alcidae. These numbers are likely an underestimation since we were unable to find bycatch estimates, or to extrapolate estimates from available bycatch data for 12 (out of 34) European coastal states. Our assessment also identified significant data gaps in key areas such as Gran Sol (in the north‐east Atlantic), the central and Eastern Mediterranean and the Black Sea. Combining systematic data collection with immediate implementation of mitigation measures will be crucial to fill in knowledge gaps, reduce current mortality levels and meet international conservation commitments such as those of the European Union and the Convention on Migratory Species.

Population declines of vultures of the genus Gyps in the Indian Subcontinent in the 1990s and 2000s were among the most rapid global population declines recorded for any bird species. Multiple lines of evidence identified veterinary treatment of cattle with the non‐steroidal anti‐inflammatory drug (NSAID) diclofenac as the principal cause of the vulture population crash. Diclofenac causes kidney failure and death within a few days of a vulture scavenging the carcass of a recently treated cow. Despite coordinated regulatory action by governments to ban veterinary diclofenac in South Asia, enforcement has been incomplete in many areas. Progress in preventing the veterinary use of other NSAIDs now also known to be vulture‐toxic has been slow. A mosaic of inconsistent licensing processes currently exists across South Asian vulture range states, leading to issues with successful policy implementation, legitimacy and effectiveness. At present, mandatory safety testing to ensure NSAIDs already in use or proposed for use are vulture‐safe is not part of drug licensing procedures in any vulture range state. In 2021, Bangladesh became the first country to ban a vulture‐toxic NSAID, in addition to diclofenac, by banning veterinary use of ketoprofen. In 2023, India became the second country to take this step when the government announced a ban on veterinary aceclofenac and ketoprofen. This government action in India may have been triggered by a recent legal challenge. Despite its veterinary use now being banned in South Asian and the Middle Eastern countries, diclofenac has been authorised for sale since 2013 as a veterinary drug in Spain, even though Spain holds 90% of the vulture population of Europe. The European Commission's decision to leave the authorisation of this drug to Member States is at odds with a central pillar of environmental law in the European Union (EU): the precautionary principle. Furthermore, this approach is not consistent with the stringent standards and burden of proof applied to the licensing of EU plant protection products. Solution. A solution to this lack of protection of Gyps vulture populations is for regulatory regimes for veterinary NSAIDs to be augmented.

This study focuses on the interplay between specific relations to nature and more abstract concepts and values regarding the nature of humans and nature and the relationships between humans and nature. We conducted Q sorts and interviews with 25 individuals who were growing plants in gardens, allotments or different kinds of agricultural settings in Scotland. We identified three discourses representing different ways of conceptualising human-nature relationships, namely: 1) Guardianship of fragile nature; 2) Partnership with powerful nature; and 3) Rational anthropocentric management. The different discourses implied different ways of approaching environmental issues and the right way for humans to relate to nature. While the three discourses represented different understandings of human-nature relations, there was also overlap and similarities amongst them. Cross-cutting themes included the notion of balance as a central aim of many ‘growers’ and learning as an important part of growing plants. The study also showed that the respondents’ own practices did not neatly map on to single abstract perspectives, with individuals often drawing on elements of different discourses and commenting on their contradictions. Ultimately, this connected to the question on how to find the right balance between human and non-human interests. Bringing in a relational understanding and acknowledging the plurality of perspectives on human-nature relations, as well as their contradictions, overlaps and tensions, can open up the space for alternative narratives to be reflected in policies but also that structural and systemic changes are required for people to cultivate more benign relations with other-than-humans.

Half of all migratory bird species have declined over the past 30 years, with intercontinental migrants declining faster than their short‐distance migratory counterparts. One potential cause of these declines is habitat loss and degradation on tropical wintering grounds, where agricultural conversion of natural habitats and intensification of traditional, low‐intensity agricultural systems are frequently occurring. Although the broad patterns of wintering migrant abundance are well understood along most flyways, how species' habitat associations vary across disturbance gradients in agricultural landscapes remains a key question, with implications for landscape‐level farm management and restoration activities. We used 328 point count locations and associated habitat assessments targeted at a cohort of eight severely declining Afro‐Palaearctic migratory passerines in the Guineo–Congolian transition zone of Western Africa to model the probability of the presence of migrants within grass, shrub, forb and forest‐covered areas. We found support for the widespread use of early successional habitats retained within traditionally managed farmland by migrants. Most species utilize scrubland on fallows within the agricultural mosaic, especially Spotted Flycatcher, Garden Warbler, Melodious Warbler, Whinchat and Common Nightingale. Only Pied Flycatcher relied upon mature forested areas. The avoidance of mature forested habitats by most species suggests that habitat requirements of severely declining migrant birds must be explicitly considered within conservation and restoration schemes, via mechanisms to retain low‐intensity farming, especially short‐term abandoned fallows that regenerate scrubby areas within the agricultural matrix. Any habitat management within the agricultural matrix should be considered in the context of the needs of local communities.

Aim Competition is often proposed to drive niche segregation along multiple axes in speciose communities. Understanding spatial partitioning of foraging areas is particularly important in species that are constrained to a central place. We present a natural experiment examining variation in habitat preferences of congeneric Southern Ocean predators in sympatry and allopatry. Our aim was to ascertain consistency of habitat preferences within species, and to test whether preferences changed in the presence of the congener. Location Southern Hemisphere. Taxon Multiple colonies of both species within the genus Phoebetria (sooty albatrosses). Methods The two Phoebetria albatrosses breed on islands located from ~37–55°S – sooty albatrosses ( P. fusca ) in the north and light‐mantled albatrosses ( P. palpebrata ) in the south – with sympatric overlap at locations ~46–49°S. We analysed GPS and PTT tracks from 87 individuals and multiple remotely sensed environmental variables using GAMs, to determine and compare the key factors influencing habitat preference for each species at each breeding colony. Results While foraging habitat preferences are consistent in light‐mantled albatrosses, there is divergence of preferences in sooty albatrosses depending on whether they are in sympatry with their congener or in allopatry. Main Conclusions This study represents the most comprehensive work on this genus to date and highlights how habitat preferences and behavioural plasticity may influence species distributions under different competitive conditions.

For almost a century, the term ‘flyways’ has been used to order relations over time and space. It has been used to coordinate scientific research and communication as well as monitoring and management efforts for waterbird conservation. In this article, we revisit the concept of ‘boundary object’ (Star and Griesemer 1989) to investigate how this term ‘flyways’ has been central to common efforts while also having multiple meanings for the actors it connects. The article discusses both contemporary and historical achievements of the term by analysing its underlying knowledge infrastructure. We account for the complex assemblages of social, material, natural, and technical systems that shape how the term ‘flyway’ has been functioning as a boundary object and how this has changed over time. By discussing how the term ‘flyways’ as a boundary object and its underlying knowledge infrastructure shape each other, we empower the actors to define, visualise, communicate, and imagine flyways in more purposeful ways. Our analysis contributes to the literature on boundary objects and knowledge infrastructures by expanding their original definitions, arguing for a co-productive relation between them.

Malaria remains the most important arthropod-borne infectious disease globally. The causative agent, Plasmodium, is a unicellular eukaryote that develops inside red blood cells. Identifying new Plasmodium parasite species that infect mammalian hosts can shed light on the complex evolution and diversity of malaria parasites. Bats feature a high diversity of microorganisms including seven separate genera of malarial parasites. Three species of Plasmodium have been reported so far, for which scarce reports exist. Here we present data from an investigation of Plasmodium infections in bats in the western Guinean lowland forest in Sierra Leone. We discovered a new Plasmodium parasite in the horseshoe bat Rhinolophus landeri. Plasmodium cyclopsi infections in a member of leaf-nosed bats, Doryrhina cyclops, exhibited a high prevalence of 100%. Phylogenetic analysis of complete mitochondrial genomes and nine nuclear markers recovered a close relationship between P. cyclopsi and the new Plasmodium parasite withthe rodent species Plasmodium berghei, a widely used in vivo model to study malaria in humans. The data suggests that the ‘‘rodent/bat” Plasmodium (Vinckeia) clade represents a diverse group of malarial parasites that would likely expand with a systematic sampling of small mammals in tropical Africa. Identifying the bat Plasmodium repertoire is central to our understanding of the evolution of Plasmodium parasites in mammals.

Irruptions by boreal seed‐eating and frugivorous birds are assumed to be driven by the production of seeds and fruits, crops of which are highly variable between years. Using data from Sweden, we tested whether irruptions of Common Crossbills Loxia curvirostra were correlated with low Norway Spruce Picea abies seed production in the same year as the irruption and/or high seed production in the year prior to an irruption. Similar tests were made for Parrot Crossbill Loxia pytyopsittacus irruptions in relation to Scots Pine Pinus sylvestris seed production. In northern Europe, these conifers represent the key food species of the two crossbill species, respectively. Despite differing times that seeds take to mature and asynchronous seed production between the two conifer species, including a 3‐year cycle for Norway Spruce, the two crossbill species often irrupted in the same year as one another. Analyses showed that irruptions into Britain and other parts of western Europe by both crossbill species were correlated with low seed production by Norway Spruce in Sweden. Low seed production by Scots Pine had a marginally non‐significant additive effect on both crossbill species. In a second set of analyses, the best‐fitting model was one in which low seed production by both conifers in a given year and high seed production in the previous year were each correlated with large numbers of irrupting Common and Parrot Crossbills. The models indicate that the incidental co‐occurrence of low seed production of Norway Spruce and Scots Pine in a given year, after a year of high seed production, may result in an irruption. The seed production of Norway Spruce and Scots Pine in Sweden was correlated with production by the same species in Finland, indicating widespread synchrony of cropping across northern Europe.

We present a genome assembly from an individual male Tetrao urogallus (the Western Capercaillie; Chordata; Aves; Galliformes; Phasianidae). The genome sequence is 1,013.2 megabases in length. Most of the assembly is scaffolded into 39 chromosomal pseudomolecules, including the Z sex chromosome. The mitochondrial genome has also been assembled and is 16.68 kilobases in length.

Building upon the concept of mainstreaming social sciences within conservation, we consider their mainstreaming, and so integration, within UK environment policy and practice (EPP) organisations. The paper responds to increasing calls to recognise the essential role of social sciences in addressing global environmental crises across policy, practice and research. An actor-oriented approach was deployed, producing empirical information from a multi-stage, co-designed, collaborative study involving 19 social scientists from a range of EPP organisations, to understand how they experience the mainstreaming of social sciences. The findings contribute to debates about the politics of knowledge in organisational domains other than those focused on research, specifically EPP organisations. Evidence was found of recent positive changes in how social sciences are perceived, resourced and utilised within EPP, as well as examples of positive impact. However, although EPP organisations are recognising the opportunities that social sciences expertise brings, in practice social sciences still face barriers to effective integration. Many of the challenges faced by the social sciences within academic multi-discipline research (e.g., late, narrow, or selective enrolment) were also experienced in EPP organisations, along with some unique challenges. Informed by the findings, the paper proposes a set of integration indicators designed to assess organisational progress toward addressing the observed challenges. It is recommended that these indicators are employed at a strategic level by EPP organisations seeking to better integrate social sciences expertise into their work.

Conditions experienced by an individual during migration have the potential to shape migratory tactic and in turn fitness. For large birds, environmental conditions encountered during migration have been linked with survival and subsequent reproductive output, but this is less known for smaller birds, hindering our understanding of mechanisms driving population change. By combining breeding and tracking data from 62 pied flycatchers (Ficedula hypoleuca) representing two breeding populations collected over 2016-2020, we determine how variation in migration phenology and tactic among individuals affects subsequent breeding. Departure date from West African non-breeding areas to European breeding grounds was highly variable among individuals and had a strong influence on migration tactic. Early departing individuals had longer spring migrations which included longer staging duration yet arrived at breeding sites and initiated breeding earlier than later departing individuals. Individuals with longer duration spring migrations and early arrival at breeding sites had larger clutches, and for males higher fledging success. We suggest that for pied flycatchers, individual carry-over effects may act through departure phenology from West Africa, and the associated spring migration duration, to influence reproduction. While our results confirm that departure date from non-breeding areas can be associated with breeding success in migratory passerines, we identify spring staging duration as a key component of this process.

In 2022, highly pathogenic avian influenza (HPAI) A(H5N1) virus clade 2.3.4.4b became enzootic and caused mass mortality in Sandwich Tern Thalasseus sandvicensis and other seabird species across northwestern Europe. We present data on the characteristics of the spread of the virus between and within breeding colonies and the number of dead adult Sandwich Terns recorded at breeding sites throughout northwestern Europe. Within two months of the first reported mortalities, 20,531 adult Sandwich Terns were found dead, which is >17% of the total northwestern European breeding population. This is probably an under-representation of total mortality, as many carcasses are likely to have gone unnoticed and unreported. Within affected colonies, almost all chicks died. After the peak of the outbreak, in a colony established by late breeders, 25.7% of tested adults showed immunity to HPAI subtype H5. Removal of carcasses was associated with lower levels of mortality at affected colonies. More research on the sources and modes of transmission, incubation times, effective containment, and immunity is urgently needed to combat this major threat for colonial seabirds.

Reed warblers are widespread throughout Eurasia, Africa, and Australasia, and many species undertake long seasonal migrations. By contrast, other species of the genus Acrocephalus are sedentary and endemic to single oceanic islands. The Pitcairn Reed Warbler Acrocephalus vaughani is confined to the small volcanic island of Pitcairn in the South Pacific Ocean, and no population assessments have ever been conducted for this species. Due to its restricted range, the presence of invasive species, and the loss of natural habitat, the species is considered as globally “Endangered”, but its actual conservation status is entirely speculative. We conducted transect surveys and nest monitoring in the austral summer of 2022/23 and present abundance estimates for the species. We counted between 51 and 158 reed warblers along 54 transects that were each 100 m long and covered all habitats and roughly 13% of the vegetated island area. Using binomial mixture models accounting for imperfect detection and habitat variation in abundance, we estimated that Pitcairn may hold 1,568 (95% confidence interval 812–3,237) Pitcairn Reed Warblers, and that the species appeared to be most abundant in introduced Rose Apple Syzygium jambos stands. Based on the monitoring of 49 nests, of which only four failed to fledge any young, we estimated that Mayfield nest survival rate was 0.69 and estimated productivity was 1.07 (± 0.39 standard deviation) fledglings per nest. Assuming that Pitcairn Reed Warblers have similar annual survival probabilities as other island reed warblers, the productivity appears sufficient to maintain the population and there is no indication that the species has decreased significantly over the past three generations. Given the limited extent of occurrence, and the stable current population size between 442 and 2,774 mature individuals, we recommend that the global conservation status of the Pitcairn Reed Warbler be classified as “Vulnerable”.