The Santa Marta Sabrewing Campylopterus phainopeplus is listed as a “Critically Endangered” hummingbird endemic to the Sierra Nevada de Santa Marta (SNSM) in Colombia. Prior to 2022, there were only three documented sightings of the sabrewing since it was described in 1879, including only one record between 1946 and 2022. As a result, this “lost” species has long been one of the most poorly known birds in Colombia. We located a resident population of Santa Marta Sabrewing along the Guatapurí River near the Chemesquemena and Guatapurí villages in July 2022, and at its type locality, San José, in January 2023. Based on historical data and newly collected field observations, we assess the species’ status and describe aspects of its natural history and ecology. Our review indicates that the species has been frequently misidentified in the past, and that to date, documented evidence of its presence is limited to four localities, all of them restricted to the south-eastern slope of the SNSM, along the mid Guatapurí River basin. Consequently, this bird appears to represent a case of microendemism. This species is likely to remain listed as Critically Endangered until conclusive evidence suggests otherwise. Field observations indicate that the species is highly associated with watercourses, where males hold year-round territories and form leks. We obtained records of males in mid-elevation habitats (1,150–1,850 m) for 16 consecutive months between July 2022 and October 2023, suggesting that the species might not be an elevational migrant, as previously speculated. More information is needed to understand the species’ ecology so that effective conservation actions can be designed in collaboration with the indigenous communities with which the species coexists.

We examined a zooarchaeological assemblage from Badger Island, a 12.4 km2 landbridge island in the Furneaux Group, Bass Strait, south-eastern Australia. The accumulation consisted of Pleistocene and Holocene strata that were rich in mammal remains. Small mammal remains were accumulated by owls, whereas large mammal remains were accumulated by people and/or autochthonous mortality. The Pleistocene fauna was dominated by grassland mammals, particularly Mastacomys fuscus (Broad-toothed Rat), but these gradually declined and were largely replaced by forest–woodland dwelling mammals in the Holocene. The same pattern of faunal change has been observed on the large main island of Tasmania (∼65,000 km2), suggesting changes observed at Beeton Rockshelter are representative of the region. Because all of the Furneaux Group Islands were united as one landmass in the past, the fossil fauna observed in Beeton Rockshelter is relevant to conservation-oriented mammal-restoration initiatives, which are being considered throughout the entire Furneaux Group.

Species abundances and richness are central parameters in ecology and crucial for describing diversity and composition across environments. Understanding how they vary in natural environments is critical for informed conservation decisions, especially in the face of anthropogenic pressures, such as deforestation and climate change. We evaluate the influence of landscape and local habitat variables on the richness and abundances of lizards in the Caatinga, the largest continuous block of seasonally dry tropical forests. We sampled seven lizard communities for three months using visual encounters along transects. We recorded landscape and microhabitat variables and evaluated their influence on lizard species richness, diversity, and occurrence using model selection. Ten lizard species were recorded, with Tropidurus semitaeniatus, Ameivula ocellifera, and Tropidurus hispidus being the most abundant. Topographic complexity and the number of rocky outcrops positively affect species richness and diversity by promoting environmental heterogeneity and hence increasing refuges, shelters, and thermoregulation sites. Different microhabitat and landscape variables were important predictors of the occurrences of individual lizard species. The quantity of rocks significantly increased the likelihood of Tropidurus semitaeniatus occurrence, while litter negatively affected Tropidurus hispidus, and fallen logs increased the probability of Ameiva ameiva occurrence. We argue that preserving topographically complex regions is essential for maintaining the diversity of lizards in the Caatinga biome.

Obligate avian scavengers, such as the “Critically Endangered” California Condor Gymnogyps californianus, face significant threats from human activities and environmental changes. This study examines the home range and presence of reintroduced California Condors in a protected area in Baja California, Mexico, focusing on the influences of seasonality, biological factors, and food supplementation. Using spatial data collected over 12 months with telemetry equipment, we analysed condor movements within and beyond the boundaries of the Parque Nacional Sierra de San Pedro Mártir. Our findings reveal that condors spend over half their time within the protected area, with an increased presence during winter months. Supplementary feeding programmes significantly increased condor presence within the park, particularly in spring and summer. Home range analyses showed that season significantly influenced home range sizes, with smaller ranges observed during winter compared with other seasons. Additionally, male condors had larger home ranges than females during spring, but no significant sex differences were observed in other seasons. Age did not have a significant effect on home range size. This study emphasises the importance of protected areas and supplementary feeding programmes in condor conservation, highlighting the necessity of continuous monitoring and management to help support this iconic species.

This study examines mortality of the Amur tiger Panthera tigris altaica caused by traffic collision incidents in the Russian Far East from 1980 to 2023. Forty-six per cent of mortality incidents occurred within the last 4 years of this period (2020–2023) following an outbreak of African swine fever, which led to a reduction of prey available for tigers. Using multiple regression analysis, we identify significant predictors of tiger mortality, including road type, biotope, and distances to settlements and federally protected areas. We identified five locations with concentrations of tiger mortality, with four of these near protected areas comprising 54% of all incidents. Asphalt roads have an elevated risk of tiger deaths during the winter, whereas unpaved roads have elevated risk during warmer months. Wildlife-friendly road planning, including crossings and enhanced night-time controls, is crucial for reducing mortality and ensuring the survival of this species amidst increasing development of human infrastructure. This study highlights the urgent need for targeted conservation efforts to reduce traffic-related risks to the Amur tiger.

Cycads, an ancient lineage, face a higher threat of extinction than any other plant group. To address this urgent issue, a more comprehensive method for assessing extinction threat, the Conservation and Prioritization Index (CPI), is proposed and tested for cycads in the State of Veracruz, Mexico. The CPI is a multifaceted approach that incorporates techniques used in conservation status assessments by the IUCN and the Mexican NOM-059-SEMARNAT-2010 but incorporates other information, including georeferenced distribution data, endemism in Veracruz, number of locations, extent of occurrence, and distribution area. Using CPI, correlations were found between longitude and extinction risk for Ceratozamia species in Veracruz. Zamia vazquezii and Z. inermis were assessed to have the highest level of extinction risk. Overall, this study indicates that a more holistic approach, incorporating broader sources of environmental health, can be used to more effectively and proactively manage extinction threats to cycads in Veracruz. In this sense, Veracruz can serve as a model for conservation planning in different states in Mexico and worldwide. CPI is a tool that can be applied to other regions to manage another threatened biota. This method enhances objectivity and effectiveness in conservation efforts, promoting data-driven decision-making that can be used globally.

The ʻuaʻu, or Hawaiian Petrel Pterodroma sandwichensis, is an endangered seabird endemic to the Hawaiian Islands. Genetic, morphometric, and behavioural differences have previously been found between different island populations of the species. Understanding the breeding phenology of different populations of ʻuaʻu is therefore vital for conservation actions targeting the species. To assess breeding phenology of ʻuaʻu on the islands of Kauaʻi and Lānaʻi, two main techniques were used over a 12-year period: direct burrow monitoring and burrow cameras. The breeding phenology of the ʻuaʻu is described based on this data. On Kauaʻi, breeding birds arrive in the middle of April, undergo an exodus of approximately one month, and return to lay in the beginning of June. Incubation continues until early August, followed by chick-rearing, which ends on average two weeks before the chick fledges. Fledging starts in mid-October, peaks in mid-November, and ends in the third week of December. Lānaʻi birds arrive two weeks earlier and fledge one week earlier than on Kauaʻi. On both islands breeding was asynchronous with a 68-day (Kauaʻi) and 48-day (Lānaʻi) gap between first and last fledging birds. Considering phenology data across its entire Hawaiian range, ʻuaʻu first arrive on east Maui, then Lānaʻi, Hawaiʻi Island, and Kauaʻi in that order. These differences in timing presumably reflect and/or reinforce genetic differentiation between subpopulations of the species. The utility of this information is discussed in terms of directing management actions towards key periods of vulnerability to introduced predators, including peak incubation, chick emergence, and chick exercise periods. Description of island-specific phenologies is also critical to inform efforts to rescue fledglings disoriented by artificial light, mitigate powerline collisions, and refine existing monitoring and restoration projects. Future work using acoustic monitoring and data collected at social attraction sites is recommended for assessing the phenology of non-breeders at colonies.

Penguins include 18 species of seabirds distributed in the Southern Hemisphere. Climate change is a growing problem that affects penguins, especially those living in Antarctica, making them some of the most currently endangered species. Loss of habitat, commercial fishing and infectious diseases spread by anthropogenic activities in the Southern Ocean are threats facing penguins. In addition, environmental changes affect the distribution of free-living species that act as intermediate hosts for parasites (e.g. krill, fish) and consequently their transmission dynamics and distribution. The present work aims to provide an update on macro- and microparasites recorded in all penguin species in wildlife. Based on published records from penguins, we provide a list of 157 parasite taxa recorded in all penguin species. The list includes 54 helminths, 45 arthropods, 39 bacteria and 19 protozoa reported in 207 scientific publications. Most papers were focused on the genus Spheniscus. In the analysis, we identify the distribution of parasites among hosts to better predict the disease risk facing their populations worldwide. Some pathogenic effects of the parasites found are discussed.

Maize (Zea mays L.) is one of the main staples in the Peruvian Andes. Phenotypic diversity is extremely high in terms of plant morphology, grain colour, grain size and uses. However, little is known about the genetic component of the Peruvian maize. Genotyping-by-sequencing was used, for the first time, to infer the genetic diversity and population structure of 25 accessions of maize collected from two ecoregions of the departments of the Peruvian highlands, Cajamarca and Huancavelica, to provide a basis for the conservation and breeding of this crop genetic resource. A total of 29,332 single-nucleotide polymorphisms were identified along all 10 chromosomes of maize. STRUCTURE analysis revealed two clusters (open-pollinated cultivars and landraces). Principal coordinate analysis and our dendrogram showed that these accessions of Peruvian maize do not group based on their geographic origin but on their improvement status, however, this is weakly supported. Average genetic diversity was very high (0.35). Analysis of molecular variance showed a reduced variation between populations (2.85%) and indicated that variability within populations is 97.15%. The lowest population divergence was zero for populations of Colcabamba versus Pichos and Daniel Hernandez versus Colcabamba and the highest population divergence (0.041) was observed for population Cajamarca versus Santiago de Tucuma. As expected, FIS values were positive. Additional samples from other Andean and west coast Peruvian localities are needed to provide a better understanding of the genetic components of this important crop aiming to develop a modern breeding programme of maize in Peru.

Through compositional inclusion or exclusion, the photograph can assert and communicate what belongs in a picture, in a landscape, in an ecosystem. It can illuminate what we deem conservation-worthy, or, on a larger scale, which extinctions are attention-worthy. Photographic practice helps to illuminate the active nature of extinction, and our choices as actors and witnesses within that process. Here, researchers from the University of Leeds’ Extinction Studies Doctoral Training Programme present individual reflections on interdisciplinary practice-led research in the Scottish Small Isles. We consider how photography, as a form of praxis, can generate new forms of knowledge surrounding extinction: its meanings, representations, and legacies, particularly through visual representation. We offer seven perspectives on contemporary image-making, from disciplines including philosophy, conservation biology, literature, sociology, geology, cultural anthropology, and palaeontology. Researchers gathered experiential, ethical, even biological meanings from considering what to include or exclude in images: from the micro to the macro, the visible to the invisible, the aesthetic to the ecological. We draw conclusions around meaning-making through the process of photography itself, and the tensions encountered through framing and decision-making in a time of mass ecological decline.

Land-use changes are considered one of the main drivers of biodiversity loss. Agricultural intensification, pastoral abandonment, and changes in forest management have led to the homogenisation of landscapes. In particular, the encroachment of grasslands and the densification of forests that are no longer pastured threaten species that require multiple habitats to nest and forage, such as the European Nightjar Caprimulgus europaeus. Whereas previous studies have focused on understanding factors influencing the decrease of nightjars at regional or national scales, here, we aimed to assess fine-scaled habitat selection by nightjars within nesting and foraging sites based on high-resolution GPS tracking data. Vegetation structure and composition were quantified in the field. In the nesting habitat, nightjars prefer open forests with a low percentage of trees and where the ground is not covered by more than 40% of grass and crawling bushes (dwarf bushes such as Juniperus species). In contrast, when foraging, nightjars select open grasslands and biodiversity-friendly managed vineyards, both richly structured, i.e. interspersed or surrounded by other land-use types such as hedges or isolated trees. Both the nesting and foraging habitats are currently threatened, either by the abandonment of forest management, which makes stands denser and more homogeneous, or through agricultural intensification, which reduces land-use diversity. Clear habitat-specific management recommendations and political incentives are needed to simultaneously preserve and/or restore these critical habitats, which are important for nightjars that use complementary resources for nesting and foraging.

A left-variable word over an alphabet A is a word over $A \cup \{\star \}$ whose first letter is the distinguished symbol $\star $ standing for a placeholder. The ordered variable word theorem ($\mathsf {OVW}$), also known as Carlson–Simpson’s theorem, is a tree partition theorem, stating that for every finite alphabet A and every finite coloring of the words over A, there exists a word $c_0$ and an infinite sequence of left-variable words $w_1, w_2, \dots $ such that $\{ c_0 \cdot w_1[a_1] \cdot \dots \cdot w_k[a_k] : k \in \mathbb {N}, a_1, \dots , a_k \in A \}$ is monochromatic.

In this article, we prove that $\mathsf {OVW}$ is $\Pi ^0_4$-conservative over $\mathsf {RCA}_0 + \mathsf {B}\Sigma ^0_2$. This implies in particular that $\mathsf {OVW}$ does not imply $\mathsf {ACA}_0$ over $\mathsf {RCA}_0$. This is the first principle for which the only known separation from $\mathsf {ACA}_0$ involves non-standard models.