Anthropogenic Threats Research Articles

Habitat characterization and decline of Critically Endangered Onobrychis conferta subsp. conferta

Rare endemic plant species are very susceptible to anthropogenic threats and natural changes, thereby facing a high risk of extinction. The Mediterranean Basin supports a rich flora with high percentages of endemic species. An iconic case of Mediterranean narrow endemic plant taxon is represented by Onobrychis conferta subsp. conferta (Desf.) Desv. (Fabaceae). Management of this species requires better information on its habitat requirements and population status. Field surveys and historical records were used to characterize the distribution of O. conferta in Tunisia. Habitats were characterized using topography, soils, climate, and land cover variables. Expeditions on ten previously reported sites revealed the presence of O. conferta in only one of the previous recorded localities and, for the first time, in two new localities. We recorded a sharp decreasing trend for the total number of plants per population in all locations over 6-year period. Our findings showed that the current status of O. conferta in Tunisia is Critically Endangered (CR). Onobrychis conferta faces an extremely high risk of extinction in the wild. Therefore, prompt comprehensive conservation actions are needed to ensure its survival. We propose a conservation and recovery recommendations including in situ and ex situ conservation actions. In situ actions are aimed at minimizing the effects of the identified threats and to create new populations of O. conferta in its characterized habitat. Ex situ actions include an environmental education campaign and seed preservation.

Coral reefs and climate change: Examining two institutional approaches to managing a novel marine ecosystem

Much of Florida’s economy is tied to the third-largest barrier reef in the world, the Florida Reef Tract. However, because of anthropogenic threats, it is not the thriving ecosystem it once was, and its persistence requires new, unconventional management strategies. Two entities have emerged to address this problem: the Florida Keys National Marine Sanctuary, a formally structured regulatory authority, and the Southeast Florida Coral Reef Initiative, an informal network of stakeholder partnerships. We therefore ask: How does coral reef management vary over the different spatial extents and structures of these organizations, and how do these organizations vary in incorporating important aspects of novel ecosystem management? Using 1122 statements from news documents, public meeting transcripts, and stakeholder interviews, we compare the institutional elements of each organization and determine the importance they place on five management considerations. Our results indicate significant institutional differences between the two, one marked by a focus on regulations and authority and the other by a focus on data collection and preparedness. Understanding these institutional differences promotes a better understanding of how adaptive governance can be iteratively applied in novel ecosystems to improve management under rapidly changing conditions.

Dietary niche of the endangered Psychedelic Rock Gecko (Cnemaspis psychedelica) in southern Vietnam

Abstract The Psychedelic Rock Gecko (Cnemaspis psychedelica), is a species endemic to southernmost Vietnam. It was recently assessed as Endangered in the IUCN Red List and also included in the CITES Appendix I, due to anthropogenic threats such as habitat degradation and over-collection for the pet trade. To protect wild populations and the natural habitat of this species, knowledge of its demography and ecology is essential to implement fitting conservation measures. In this study, we conducted field surveys on Hon Khoai Island, Ca Mau Province, southern Vietnam in both dry and wet seasons, and obtained food contents of 114 individuals of C. psychedelica by water-flushing the stomach without sacrificing them. Consequently, 685 invertebrate items were identified, belonging to 24 different prey types of 20 invertebrate orders, as well as flatworms, snails and plant parts. Araneae, Blattodea, Hymenoptera and Isoptera were identified as the most important prey of C. psychedelica, among which Araneae accounted for the highest percentage, and thus the highest importance index, during the dry season and Hymenoptera during the wet season. There was a large overlap in the trophic niche between the two seasons, and between males and females of C. psychedelica. This study shows that not only suitable habitat but also a particular food spectrum is a requirement for the species and this, in addition, is important to optimize conservation breeding programs.

Citizen Science for Environmental Monitoring in the Eastern Region of Bolivia

The eastern region of Bolivia is of high conservation interest due to the presence of the Chiquitano Dry Forest, Dry Chaco, Pantanal and Cerrado ecoregions. However, this region is under high pressure from various anthropogenic threats, which requires continuous monitoring. An alternative for this monitoring is the use of mobile applications designed under the concept of citizen science, in which local stakeholders are part of the process of obtaining information and finding solutions to environmental problems in their territories. The main objective of this study was to evaluate the information obtained during environmental monitoring with a citizen science approach in the eastern region of Bolivia. We developed a public electronic form for the ArcGIS Survey123 mobile application to capture spatial data of nine thematic variables. Between 2021 and 2023, we conducted 16 training courses in 12 population centers, with attendees from 98 communities in 6 municipalities in the region. A total of 360 volunteers from different sectors participated in the training, including technicians from public and private institutions, park rangers, community representatives and citizens. We obtained a total of 379 records, of which 70.4% were recorded near communities and the rest within protected areas. The results were reclassified and grouped into three clusters: human activities, water resources and biodiversity. In the human activities cluster, the categories with the highest number of records were wildfires and deforestation. In the water resources cluster, the categories with the most records were cattle waterholes and streams, but one of the most notable records was the reduction of wetlands in a sector of the Bolivian Pantanal. In the biodiversity cluster, the main reports were for mammals, and among the most notable records obtained were the footprints of the jaguar (Panthera onca). This monitoring tool made it possible to generate and use high-quality information in different sites in the eastern region in almost real time, which could help strengthen the interactions and relationship with users in environmental dialogue and governance processes.

Animal migration in the Anthropocene: threats and mitigation options.

Animal migration has fascinated scientists and the public alike for centuries, yet migratory animals are facing diverse threats that could lead to their demise. The Anthropocene is characterised by the reality that humans are the dominant force on Earth, having manifold negative effects on biodiversity and ecosystem function. Considerable research focus has been given to assessing anthropogenic impacts on the numerical abundance of species/populations, whereas relatively less attention has been devoted to animal migration. However, there are clear linkages, for example, where human-driven impacts on migration behaviour can lead to population/species declines or even extinction. Here, we explore anthropogenic threats to migratory animals (in all domains - aquatic, terrestrial, and aerial) using International Union for the Conservation of Nature (IUCN) Threat Taxonomy classifications. We reveal the diverse threats (e.g. human development, disease, invasive species, climate change, exploitation, pollution) that impact migratory wildlife in varied ways spanning taxa, life stages and type of impact (e.g. from direct mortality to changes in behaviour, health, and physiology). Notably, these threats often interact in complex and unpredictable ways to the detriment of wildlife, further complicating management. Fortunately, we are beginning to identify strategies for conserving and managing migratory animals in the Anthropocene. We provide a set of strategies that, if embraced, have the potential to ensure that migratory animals, and the important ecological functions sustained by migration, persist.

Vulnerability of terrestrial vertebrate food webs to anthropogenic threats in Europe.

Vertebrate species worldwide are currently facing significant declines in many populations. Although we have gained substantial knowledge about the direct threats that affect individual species, these threats only represent a fraction of the broader vertebrate threat profile, which is also shaped by species interactions. For example, threats faced by prey species can jeopardize the survival of their predators due to food resource scarcity. Yet, indirect threats arising from species interactions have received limited investigation thus far. In this study, we investigate the indirect consequences of anthropogenic threats on biodiversity in the context of European vertebrate food webs. We integrated data on trophic interactions among over 800 terrestrial vertebrates, along with their associated human-induced threats. We quantified and mapped the vulnerability of various components of the food web, including species, interactions, and trophic groups to six major threats: pollution, agricultural intensification, climate change, direct exploitation, urbanization, and invasive alien species and diseases. Direct exploitation and agricultural intensification were two major threats for terrestrial vertebrate food webs: affecting 34% and 31% of species, respectively, they threaten 85% and 69% of interactions in Europe. By integrating network ecology with threat impact assessments, our study contributes to a better understanding of the magnitude of anthropogenic impacts on biodiversity.

Changing Waves: Maritime Community Cultural Responses to the Anthropocene in Tambak Lorok, Semarang

Climate change rooted in the Anthropocene significantly impacts global ecological changes, including coastal ecosystems. As a coastal city, Semarang City experiences various phenomena related to the Anthropocene caused by humans, or anthropogenic, which affects coastal activities, including aspects of the community. Tambak Lorok community is among the communities most affected by anthropogenic threats. Therefore, Tambak Lorok fishermen continue to build resilience in running their livelihoods. This research used a mixed method through the Sustainable Livelihood Approach (SLA). Quantitative approach in the form of survey data collection on the Joint Business Group (KUB) representative is carried out, while a qualitative approach is used to delve into and understand the context of SLA further. The results show that the Tambak Lorok fishing community’s livelihood system can be analyzed through five capital assets: human capital, social capital, natural capital, physical capital, and financial capital. These five aspects get a variety of physical, social, and intervention vulnerabilities that create resilience and culture in the intersection. The KUB, as a representative of the fishing community, strengthens their sustainable livelihood in three ways: changing their fishing gear sustainably, diversifying income to FAD, and utilizing other alternatives outside fisheries sector. All of these alternatives to livelihood were achieved through collaborative governance with various policies and institutions as a sustainable livelihood strategy.

Factors regulating incubation temperature and thermal stress in hawksbills in St. Croix, USVI

The hawksbill sea turtle is listed as Critically Endangered under the IUCN Red List and has been slow to recover in the Caribbean due to historical exploitation and ongoing anthropogenic threats. In turtles, sex and reproductive success are determined by incubation temperatures, whereby lower temperatures produce male hatchlings and higher temperatures produce female hatchlings. As incubation temperatures increase due to climate change, nests are predicted to produce predominantly female hatchlings, threatening sex ratios, reproductive success, and species persistence. One of the largest remaining nesting hawksbill populations within the USA nests on Buck Island. This study aimed to (1) assess the factors driving incubation temperatures and (2) identify the relationship between hatch success and the proportion of time exposed to increasing incubation temperatures. Nest incubation temperatures, beach sector, habitat type, deposition month, percent soil composition, hatch success, and emergence success data were collected from 2019 to 2021. Differences in incubation temperatures across these factors confirmed that the absence of vegetative cover is increasing incubation temperatures on Buck Island, leading to reduced hatchling survival. Results from this study indicate that declines in hatch success may be driven by long-term exposure to temperatures that were previously considered in the literature to be non-lethal to embryos. These findings emphasize the continued need for conservation interventions to protect the future of hawksbills.

Multi-scale habitat influences sprainting and group size of a freshwater-obligate smooth-coated otter (Lutrogale perspicillata) in Tungabhadra Otter Conservation Reserve, India

BackgroundThe impact of changing land-use patterns and associated anthropogenic threats on scale-dependent habitat use of semi-aquatic mustelids in scent-marking and social behaviour can provide important insights into the habitat ecology of smooth-coated otters (Lutrogale perspicillata).MethodsWe sampled 180 stream segments (100–400 m) as spatial replicates of 60 1-km2 sites to record indirect evidence (i.e. spraints and mass latrine sites) and group sizes of smooth-coated otters along the Tungabhadra Otter Conservation Reserve (TOCR) during the dry season. To quantify habitat, we recorded stream characteristics, riparian vegetation, and anthropogenic disturbances at the local scale, and hydro-environmental characteristics and land uses at the landscape scale. Using Markovian-chain detection and occupancy models, we assessed the multi-scale habitat use of otters in their selection of suitable areas for scent-marking based on repeated presence-absence data on spraint/latrine locations along the TOCR. We further used linear regression techniques to explore relationships between the number of individuals in smooth-coated otter group and hydro-environmental characteristics, spraint/latrine encounter rate, anthropogenic pressure, land cover, topography, and vegetation.ResultsAt the local scale, the probability of spraint deposition and group size decreased with anthropogenic disturbance while the probability of spraint detections decreased with grass cover. At the landscape scale, the probability of otter site use for spraint deposition and group sizes increased in southeast flowing streams. Spraint deposition increased with the proportion of sugarcane fields, whereas in contrast, group size decreased with proportion of sugarcane fields.ConclusionsOur findings highlight the first empirical evidence on multi-scale habitat use of a southern Indian population of smooth-coated otters in an inland freshwater ecosystem surrounded by the scrub jungle–agriculture matrix. We suggest that habitat models built from analytical approaches that account for correlated detections can avoid biased predictions when estimating occupancy and detection probability of semi-aquatic or riparian mammal communities with linear distributions. Our findings indicate that human activity can impose constraints on the choice of sites used for spraint deposition and preliminary patterns in otter groups. The study provides some crucial evidence on the need to maintain areas with minimal human interference for sustainability of freshwater reserves.

Ethnoveterinary medicinal plants and their utilization by the people of Soro District, Hadiya Zone, southern Ethiopia

BackgroundEthnoveterinary studies are important to maintain the sustainability of livestock health and support people’s livelihoods through the provision of food, maintaining livestock health, and other biological resources. This study was carried out in Soro District, southern Ethiopia, to identify, document and analyse plant species with ethnoveterinary uses along with the associated indigenous and local knowledge.Materials and methodsInformants were selected using purposive (key informants) and systematic random sampling (general informants) methods. Data on ethnoveterinary plants and their uses were collected through semi-structured interviews, guided field walks, 13 focus group discussions with five to seven members in each and participant observation. Informant consensus factor and fidelity level were computed to identify the most common livestock ailment categories and the best plant species with ethnoveterinary use, respectively. Preference ranking methods were used to identify the potentially effective ethnoveterinary medicinal plants for the most frequently reported livestock ailments. The use diversity of multipurpose plants with ethnoveterinary importance was analysed using the analytical methods of ethnobotany including priority ranking, comparisons and important indices. The T-test statistic was used to compare knowledge differences among different social groups.ResultsA total of 132 plant species in 120 genera and 61 families were reported by informants as having ethnoveterinary uses. The plants are said to be used by the local communities in various ways to treat 50 livestock health problems. Higher number of informants (23.77%) cited Momordica foetida for the treatment of 16 livestock ailments. The highest informant consensus value for this species is associated with its use for treating blackleg in cattle; Nicotiana tabacum was cited for the treatment of 15 livestock ailments mainly recommended for the Lumpy Skin Disease/Ailment of bovines; Croton macrostachyus for treatment of 13 livestock ailments including wooden tongue, FMD in bovines; and Gymnanthemum amygdalinum for nine ailments mainly diarrhoea of all livestock types. Achyranthes aspera is claimed to provide the most effective treatment for Aspiration pneumonia (severe coughing in bovines, sheep and goats) alone, while Croton macrostachyus, Ximenia americana, Allium sativum and Juniperus procera were indicated as potential plant species to treat Lumpy Skin Disease in bovines in the order given. The fidelity level analysis showed that Datura stramonium, Dodonaea viscosa subsp. angustifolia and Asparagus africanus were potential medicinal plant species to treat the respective ailments of rabies, Peste des petits ruminants (PPR) and evil eye/spirit. Multipurpose plant species including Prunus africanus, Combretum molle and Afrocarpus falcatus have been highly threatened as indicated by direct matrix ranking mainly due to collection of fuel wood, construction materials and making household utensils, and farm implements rather than for other uses.ConclusionSoro District has rich and diversified livestock herbal medicinal resources, and indigenous knowledge of remedy preparations and applications is transmitted through generation lines. This resource faces anthropogenic threats with deforestation being the leading factor. Consequently, ethnoveterinary medicinal plants continue to decline before adequate and proper scientific documentation and testing are made. There is a dire need for planning and implementation of appropriate in situ and ex situ conservation strategies and to strive towards ensuring the survival and sustainable utilization of such important plant resources of Soro District. This must be supported by further documentation of the associated indigenous knowledge and pharmacological testing of the key promising species including Balanites aegyptiaca (novel species/NS to treat specific ailment), Brugmansia suaveolens (novel species/NS reported first to treat Livestock ailments/LsAs), Euclea divinorum (NS to treat specific ailments), Grevillea robusta (NS), Hagenia abyssinica (NS for the reported specific ailment), Pentanema confertiflorum (NS), Juniperus procera (NS), Maesa lanceolata (NS), Millettia ferruginea (NS for reported specific ailments), Schrebera alata/NS, Securidaca longepedunculata, Spiniluma oxyacantha/NS, Vepris nobilis (novel species reported first to treat LsAs), Zanthoxylum asiaticum /NS and Ximenia americana (NS for specific ailments). This ethnoveterinary study attempted to fill part of the gaps concerning the prevalent livestock health problems and the associated indigenous and local knowledge in the area.

Ecological determinants of spotted hyena Crocuta crocuta occupancy in Comoé National Park, Côte d’Ivoire

Knowledge of the large carnivore guild is important in view of a possible lion reintroduction into the Comoé National Park (CNP), northern Côte d’Ivoire. We used camera trapping to assess activity patterns, habitat selection, and ecological factors influencing the occupancy of the spotted hyena Crocuta crocuta. Our results showed that the presence of leopard Panthera pardus, the only current other large carnivore and thus potential competitor, did not influence hyena occupancy. Hyena occupancy was only significantly related to Euclidian distance to nearest water point. Manly’s alpha habitat selection index values show a preference of spotted hyena for shrub savannah (αSa = 0.71), and Pianka’s overlap index showed low spatial competition with leopard (OIJ(PNC) = 0.12). Our findings showed that spotted hyena were mostly nocturnal, and generally active at the same time slots with leopard, leading to a high index of temporal overlap (OIJ(time) = 0.78). The kernel density estimation confirmed that spotted hyenas and leopard shared almost half of their activity patterns (Δ1 = 0.49 and 95% CI = 0.26–0.71). Prey diversity is high in CNP but anthropogenic threats appear to suppress population growth of prey and predators. Conservation efforts should continue to reduce pressures before contemplating a potential lion Panthera leo reintroduction.

Identifying global conservation priorities for terrestrial vertebrates based on multiple dimensions of biodiversity.

The Kunming-Montreal Global Biodiversity Framework of the Convention on Biological Diversity calls for an expansion of the current protected areas (PAs) to cover at least 30% of global land and water areas by 2030 (i.e., the 30×30 target). Efficient spatial planning for PA expansion is an urgent need for global conservation practice. A spatial prioritization framework considering multiple dimensions of biodiversity is critical for improving the efficiency of the spatial planning of PAs, yet it remains a challenge. We developed an index for the identification of priority areas based on functionally rare, evolutionarily distinct, and globally endangered species (FREDGE) and applied it to 21,536 terrestrial vertebrates. We determined species distributions, conservation status (global endangerment), molecular phylogenies (evolutionary distinctiveness), and life-history traits (functional rarity). Madagascar, Central America, and the Andes were of high priority for the conservation of multiple dimensions of terrestrial vertebrate biodiversity. However, 68.8% of grid cells in these priority areas had <17% of their area covered by PAs, and these priority areas were under intense anthropogenic and climate change threats. These results highlight the difficulties of conserving multiple dimensions of biodiversity. Our global analyses of the geographical patterns of multiple dimensions of terrestrial vertebrate biodiversity demonstrate the insufficiency of the conservation of different biodiversity dimensions, and our index, based on multiple dimensions of biodiversity, provides a useful tool for guiding future spatial prioritization of PA expansion to achieve the 30×30 target under serious pressures.

Thermal tolerance in an extremophile fish from Mexico is not affected by environmental hypoxia.

The thermal ecology of ectotherm animals has gained considerable attention in the face of human-induced climate change. Particularly in aquatic species, the experimental assessment of critical thermal limits (CTmin and CTmax) may help to predict possible effects of global warming on habitat suitability and ultimately species survival. Here we present data on the thermal limits of two endemic and endangered extremophile fish species, inhabiting a geothermally heated and sulfur-rich spring system in southern Mexico: The sulfur molly (Poecilia sulphuraria) and the widemouth gambusia (Gambusia eurystoma). Besides physiological challenges induced by toxic hydrogen sulfide and related severe hypoxia during the day, water temperatures have been previously reported to exceed those of nearby clearwater streams. We now present temperature data for various locations and years in the sulfur spring complex and conducted laboratory thermal tolerance tests (CTmin and CTmax) both under normoxic and severe hypoxic conditions in both species. Average CTmax limits did not differ between species when dissolved oxygen was present. However, critical temperature (CTmax=43.2°C) in P. sulphuraria did not change when tested under hypoxic conditions, while G. eurystoma on average had a lower CTmax when oxygen was absent. Based on this data we calculated both species' thermal safety margins and used a TDT (thermal death time) model framework to relate our experimental data to observed temperatures in the natural habitat. Our findings suggest that both species live near their thermal limits during the annual dry season and are locally already exposed to temperatures above their critical thermal limits. We discuss these findings in the light of possible physiological adaptions of the sulfur-adapted fish species and the anthropogenic threats for this unique system.

Population and conservation threats to the vulnerable Sarus crane Grus antigone in Nepal.

Globally, biodiversity is declining due to habitat loss and degradation, over-exploitation, climate change, invasive species, pollution, and infrastructure development. These threats affect the populations of large waterbird species, such as Sarus crane (Grus antigone), which inhabits agricultural-wetland ecosystems. Despite the burgeoning built-up areas and diminishing agricultural and wetland spaces, scant research investigates the impact of these changing land uses on the globally vulnerable Sarus crane in Nepal. During the pre-breeding season from April to June 2023, our comprehensive study meticulously scrutinized Sarus crane population status and factors associated with the occurrences and conservation challenges across 10 specific districts of Nepal. Our study documented a total of 690 individuals of Sarus cranes in five districts. The Lumbini Province has 685 individuals, occupying 11 roosting sites. Conversely, the remaining five districts have no Sarus cranes presence during this period. Wetland, farmland and built-up areas exhibited a significantly positive influence on Sarus crane occurrences in the Lumbini Province. Additionally, we recorded 47 fatalities of Sarus cranes over the past 13 years in the Lumbini Province due to electrocution and collisions. Our study provides a baseline dataset crucial for developing conservation policies, particularly during the dry season when Sarus crane populations tend to congregate in larger flocks. The adaptation of the Sarus crane to urbanized landscapes exposes them to several anthropogenic threats in the coming days. Therefore, protecting wetlands and farmland areas and adopting transboundary conservation approaches are imperative for the long-term conservation of the Sarus crane and its habitat.

Population genomics of the white-beaked dolphin (Lagenorhynchus albirostris): Implications for conservation amid climate-driven range shifts

Climate change is rapidly affecting species distributions across the globe, particularly in the North Atlantic. For highly mobile and elusive cetaceans, the genetic data needed to understand population dynamics are often scarce. Cold-water obligate species such as the white-beaked dolphin (Lagenorhynchus albirostris) face pressures from habitat shifts due to rising sea surface temperatures in addition to other direct anthropogenic threats. Unravelling the genetic connectivity between white-beaked dolphins across their range is needed to understand the extent to which climate change and anthropogenic pressures may impact species-wide genetic diversity and identify ways to protect remaining habitat. We address this by performing a population genomic assessment of white-beaked dolphins using samples from much of their contemporary range. We show that the species displays significant population structure across the North Atlantic at multiple scales. Analysis of contemporary migration rates suggests a remarkably high connectivity between populations in the western North Atlantic, Iceland and the Barents Sea, while two regional populations in the North Sea and adjacent UK and Irish waters are highly differentiated from all other clades. Our results have important implications for the conservation of white-beaked dolphins by providing guidance for the delineation of more appropriate management units and highlighting the risk that local extirpation may have on species-wide genetic diversity. In a broader context, this study highlights the importance of understanding genetic structure of all species threatened with climate change-driven range shifts to assess the risk of loss of species-wide genetic diversity.

Underlying and proximate drivers of biodiversity changes in Mesoamerican biosphere reserves

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.

Artificial light at night affects the timing of roosting by Chimney Swifts

Understanding the impact of anthropogenic threats, such as light pollution, on biodiversity is necessary to establish effective guidelines to protect diminishing wildlife. In this study, we examined the effect of artificial light at night (ALAN) on the roosting behaviour of Chimney Swifts Chaetura pelagica, a highly threatened migratory bird species that lives commensally with humans, where it often breeds and roosts in artificial structures such as chimneys. Although Chimney Swifts are known to use time of sunset in combination with temperature, wind and season to coordinate roost entry, we predicted that high ALAN exposure would override these natural cues and lead to a delayed entry compared with sites with less light pollution. To test this, we examined the effects of ALAN on the start and end times of entry to 21 roosting sites located along a light pollution gradient in New Jersey and the New York Metropolitan area. We found that ALAN was a significant predictor of roosting entry time, with birds entering later in sites with more light pollution. While Chimney Swifts initiated roosting earlier in the summer months compared with the autumn, this effect was absent in areas with high light pollution. These findings highlight the need to determine the causes and consequences of light pollution effects.

Governing Arctic Seals: A Longitudinal Analysis of News and Policy Discourse

Arctic states, regional and local authorities, NGOs, and Indigenous communities have debated how Arctic seals should be governed for more than a century. This governance discourse covers a wide array of issues, from seal hunting and the sale of animal products to the impacts of pollution and climate change. This article examines the frames used by political entities to discuss the regional governance of Arctic seals in the North American Arctic from 1900–2020, a period defined by landmark agreements on seals. Informed by framing and agenda-setting theory, the article employs textual analysis of policy documents and newspaper articles. These serve as a source of information and space for policy advocacy and debate to study political entities’ discourse regarding the issues and policies that shape Arctic seal governance. The analysis focuses on English-language texts from regional and local newspapers and international newspapers of record. The article identifies four dominant frames, namely perceived threats to (a) economic revenue, (b) animal welfare, (c) Indigenous ways of life, and (d) threats emanating from the involvement of NGOs in Arctic regional governance. Each of these frames is associated with one or multiple political entities involved in the regional governance of seals. The article demonstrates how the dominance of these entities and the frames they employ varies over time and corresponds to several anthropogenic threats to seals, including commercial hunting, pollution, and climate change. The article concludes that tensions between local and regional entities and international and non-Arctic entities are reflective of broader Arctic regional governance dynamics.

Diadromous fish run assessment: a double-observer model using acoustic cameras to correct imperfect detection and improve population abundance estimates

IntroductionDiadromous fish populations have strongly declined over decades, and many species are protected through national and international regulations. They account for less than 1% of fish biodiversity worldwide, but they are among the most perceptible linkages between freshwater and marine ecosystems. During their migration back and forth, diadromous fish species are subjected to many anthropogenic threats, among which river damming can severely limit access to vital freshwater habitats and jeopardize population sustainability. Here, we developed a method based on a double-observer modeling approach for estimating the abundance of diadromous fish during their migration in rivers.MethodsThe method relies on two independent and synchronous records of fish counts that were analyzed jointly thanks to a hierarchical Bayesian model to estimate detection efficiencies and daily fish passage. We used simulated data to test model robustness and identify conditions under which the developed approach can be used. The approach was then applied to empirical data to estimate the annual silver eel run in the Touques River, France.ResultsThe analysis of simulated datasets and the study case gives evidence that the model can provide robust,accurate, and precise estimates of detection probabilities and total fish abundance in a set of conditions dependent on the information provided in the data (annual distribution of fish passage, annual number of observation, pairing period, etc.).DiscussionThen, the method can be applied to various species and counting systems, including nomad acoustic camera devices. We discuss its relevance for programs on river continuity restoration, notably to quantify population restoration associated with dam removals.

Global trends in geospatial conservation planning: a review of priorities and missing dimensions

IntroductionBiodiversity underpins resilient ecosystems that sustain life. Despite international conservation efforts, biodiversity is still declining due to ongoing anthropogenic threats. Protected areas have been widely adopted as a strategy for conserving biodiversity. The use of spatial conservation planning, which prioritizes areas for protection based on geo-referenced biodiversity and ecological information as well as cost of action and their feasibility, has gained popularity in the conservation discipline in the last few decades. However, there remain gaps between plans and implementation, and negative social impacts on local communities can occur, such as tension and conflict between differing priorities, perspectives, and views.MethodsTo better understand the state of the spatial conservation field and support translating research into practice, a mixed-method approach of bibliometric (n=4133 documents) and content analysis (n=2456 documents) was used to analyze and identify key research priorities, collaborative networks, and geographic and thematic patterns.ResultsWe identified that research conducted by westernized nations dominated the field, with the United States, the United Kingdom, and Australia being responsible for almost two-thirds of the research globally, with research interest exponentially growing since 2010. Additionally, while there has been some refinement over time of algorithms and models, Zonation and Marxan methods developed in the 2000s remain the predominant choices of software, with a majority focus on marine ecosystems, birds, and mammals. We found a major gap in the use of social dimensions in spatial conservation case studies (only n=146; 6%).DiscussionThis gap highlights a lack of collaboration in conservation science between researchers and local communities who are affected by management decisions. We recommend including spatially explicit social dimensions from the onset of projects through participatory approaches, along with the acknowledgement by researchers of the importance of including diverse views in conservation planning to enhance implementation and outcomes that are relevant in local contexts. We suggest an increased reflection on types of data used for conservation but also on researchers’ personal values, biases, and positionality to encourage more ethical, applicable, and collaborative conservation science.