Richard Bischof

Animal-borne telemetry has transformed wildlife ecology, but its implementation in terrestrial systems remains constrained by the invasive, logistically demanding need to physically capture and handle animals. This traditional framework favors long-duration monitoring of relatively few individuals at the expense of temporal resolution and population coverage. Here, I propose capture-free, autonomous instrumentation as the basis for a broader shift in how wildlife telemetry data are collected and interpreted. Drawing on and synthesizing earlier developments in autonomous marking of terrestrial mammals and complementing these with proof-of-concept GPS collar deployments in an ungulate and a canid, I demonstrate the operational feasibility of this approach. Decoupling device deployment from direct human–animal interaction enables a high-throughput telemetry framework characterized by shorter deployments, expanded population coverage, and finer temporal resolution. Crucially, eliminating capture-related disturbance advances animal welfare and lessens observer effects, thus strengthening the ethical foundation and scientific validity of wildlife telemetry.

Humans perceive time as both linear and circular, which is reflected in the dichotomous way we typically organize and visualize temporal information in science: as either time series or periodic plots. These seemingly incompatible perspectives can be reconciled with a helical representation of time. Helices have been underused as a visualization of temporal information, in part because two-dimensional visualization of three-dimensional structures leaves portions of the data hidden and in part due to inherent disadvantages of radial visualizations over linear ones. Nonetheless, the helical metaphor of time brings along an important advantage: it offers an intuitive way to depict continuous time with periodicity at multiple scales. Here, I introduce a representation of time via a model of self-similar, or hierarchical, helices. Unlike conventional spiral and helix visualizations that represent periodicity at a single temporal scale, the proposed framework extends the helix concept to nested periodic structures, allowing multiple temporal scales to be represented simultaneously within a continuous temporal trajectory. This model can serve as a cognitive map or mental image of time, as well as an immersive data visualization approach for exploring patterns in timed data with nested periodicity. I demonstrate the model with a few examples (astronomical light phases, air temperature profiles, tidal cycles, and wildlife activity patterns) and provide R functions to generate interactive displays of temporal data projected onto hierarchical helix structures.

Studies can only guide conservation if their findings are informative at the scales at which practitioners and policy-makers operate. Yet, it is rarely tested whether large-scale studies reach similar conclusions to the smaller-scale studies on which conservation traditionally relies. We examine whether predictors of extinction risk are consistent across global, regional, and local scales, for 210 tropical forest mammal species (≥1 kg) that existed during the last 130,000 years, in 64 tropical forests, across three biogeographical realms. We found consistent predictors of extinction risk (body mass, generation length, diet, brain volume, and scansoriality) when analyses differed only in their spatial resolution. However, predictors differed when analyses also varied in their temporal extent. Macroecological findings about extinction risk can, thus, inform conservation at smaller scales, but they risk misidentifying threatened species if differences in temporal extent are not recognized.

Dynamic occupancy models are fundamental for understanding complex species recolonisation processes, as they allow the assessment of both colonisation and persistence probabilities over time. Using a dynamic occupancy model and a large‐scale multi‐year dataset on wolf presence collected in the Italian alpine region between 2014 and 2020, we analysed temporal trends in wolf colonisation and persistence probabilities in relation to environmental factors, prey availability and human‐related characteristics. Our results demonstrate that wolf recolonisation is an ongoing and dynamic process in the Italian Alps, with colonisation probabilities increasing throughout the study period, particularly in the northeast of the study area. Although we detected a slight positive temporal trend in the effect of human density, wolves continue to preferentially colonise natural areas, despite a decreasing availability, as evidenced by the continued positive effects of forest cover, low natural vegetation and presence of wild ungulates. Persistence probabilities remained relatively high and constant on average, but we noticed an increasingly negative effect of the presence of livestock pastures and densely populated areas. On the other hand, we noticed an increasingly positive effect of covariates associated with natural areas, such as forest cover, low natural vegetation and wild ungulate richness. This resulted in an increasingly contrasted spatial pattern in persistence probability throughout the region, likely reflecting conflict zones where wolves attempt to establish but struggle to survive. Overall, our study aligns with trends observed in other wolf populations across Europe, showing an expansion into new areas with different characteristics, highlighting potential areas of emerging conflict that warrant continued targeted monitoring. These patterns offer valuable insights for wolf conservation and management in human‐dominated landscapes.

Conflict zones are inherently hazardous and inaccessible for researchers, which results in a knowledge gap about the immediate effects of armed conflicts on the environment, particularly wildlife. We used camera-trap detections to investigate the impact of armed conflict on wildlife activity patterns before, during, and after the Russian occupation of the Chornobyl Exclusion Zone (Ukraine) in 2022 and compared it to the same period in 2021. Mammal species responded to armed conflict through immediate behavioral adjustments, including reduced activity during night and on dates when armed-conflict activities intensified. Our results provide insight into wildlife’s behavioral responses to armed conflict in real time and underscore the potential of camera trapping to quantify the ecological effects of war.

Land-use changes and habitat degradation threaten biodiversity and ecosystem functions globally. Large terrestrial mammals are particularly vulnerable due to low reproductive rates, large spatial requirements and sensitivity to human disturbances. Increasing coverage and effectiveness of protected areas (PAs) is vital to conserve mammal species and their habitats. We used camera trapping to assess the impact of human activities and landscape characteristics on diversity, occupancy and detection probabilities of 11 terrestrial mammals in northern Ukraine in 2020–2021. We evaluated the impact of human stressors and landscape modifications on species diversity, occupancy and detection probabilities across the Ukrainian Chornobyl Exclusion Zone (CEZ), regional PAs and non-PAs. We implemented hierarchical Bayesian single-species single-season occupancy models to identify the covariates that described the occupancy (Ψ) and detection (p) probabilities for each species. Species diversity, occupancy and detection probabilities were significantly higher in the Ukrainian CEZ and neighbouring Drevlianskyi Nature Reserve (highest occupancy probabilities of Przewalski’s horse, Eurasian lynx, moose and red deer) than in all other areas. PA coverage positively influenced red deer, red fox and raccoon dog occupancies, while PA protection status showed mixed effects across species. Our results demonstrate that PAs are most effective when they are large, contiguous and human access restrictions are actively enforced.

Telemetry using animal‑borne biologgers is central to wildlife research. Capturing and instrumenting wild animals, however, remains the most invasive, logistically challenging, and costly component of telemetry studies. This has contributed to current practice, which favors long tracking durations on few individuals, prioritizing longevity over temporal detail. While this model has yielded important insights, it also imposes ethical and scientific constraints. I argue that less invasive deployment methods could enable a complementary, lighter‑touch telemetry framework. Autonomous marking approaches — first developed in the mid‑1900s but now largely ignored — offer such a pathway by eliminating physical capture, restraint, and chemical immobilization. After revisiting early work on autonomous instrumentation,I present two proof‑of‑concept demonstrations of autonomous GPS‑collaring, one in an ungulate and one in a carnivore. I discuss how such approaches could support shorter deployments, improved population coverage, and finer temporal resolution. Crucially, by reducing or eliminating capture‑related disturbance, autonomous instrumentation could lessen cumulative welfare impacts and observer effects, thereby strengthening the ethical foundation and scientific validity of wildlife telemetry.

Understanding how genetic drift and inbreeding can shape phenotypic traits and the expression of rare genetic variants can be important for conservation management in small and isolated populations. Following the recolonization of the grey wolf (Canis lupus) on the Scandinavian peninsula, the population has remained small and semi-isolated. The population traces back to seven founders, only and is highly inbred. Inbreeding depression has been demonstrated including effects on reproductive output and several congenital deformities. Some wolves also show anomalous coat color, characterized by hypopigmentation displayed as white tail tips, or even larger areas of white fur. In this study, we utilized four decades of monitoring data, dating back to the recolonization of the Scandinavian peninsula in 1983, to examine the occurrence of expressed anomalous coat color investigating its origin and inheritance, genetic architecture, and the effect of inbreeding. SNP genotyping revealed a distinct haplotype linked to the Melanocyte-inducing transcription factor (MITF) gene that co-segregated with anomalous coat color, suggesting a direct causal effect of this variant. The MITF gene regulates mammal melanocyte development, which in turn affects pigmentation. Our findings demonstrate that the identified gene variant is recessive, which in the homozygous state likely causes the disruption of normal melanocyte development, leading to unpigmented or hypopigmented areas. The origin of this haplotype was traced back to a third founder, reproducing for the first time in 1991. Indeed, the genetic constraints and subsequent inbreeding shaped by few founders, small population size, and semi-isolation over several decades point towards the importance of genetic diversity and facilitated gene flow between populations, but also how such vital immigration can bring about unforeseen side effects if inbreeding continues within the immigrant lineages.

Death is an inherently spatial process. It happens to someone, somewhere, but often remains undetected in nature. Death is also the primary means by which humans regulate wildlife populations. Using a novel analytical method that accounts for the cryptic nature of the fate of individuals and one of the world’s most comprehensive non-invasive genetic monitoring datasets, we were able to map cause-specific mortality of the entire Scandinavian grey wolf ( Canis lupus ) population despite the fact that most mortality events (mean = 65%; [95% CrI: 50.3–76.8%]) remained undetected. Our analysis revealed strong spatial variation in mortality with, for example, areas with a high risk of mortality linked with the current wolf management policies. Furthermore, we showed that the risk of legal mortality increased, while the risk of mortality due to causes other than legal mortality decreased with local wolf population density. This illustrates the complex interactions between spatial determinants and cause-specific mortality and therefore the importance of considering spatial variation when estimating mortality. Maps of mortality can inform wildlife management and conservation by capturing an elusive process in population dynamics as it unfolds in time and space.

Studies can only guide conservation if their findings are informative at the scales at which practitioners and policymakers operate. Yet, it is rarely tested whether large-scale studies reach similar conclusions to the smaller-scale studies on which conservation traditionally relies. We examine whether predictors of extinction risk are consistent across global, regional, and local scales, for 210 tropical forest mammal species (≥ 1 kg) that existed during the last 130,000 years, in 64 tropical forests, across three biogeographical realms. We found consistent predictors of extinction risk (body mass, generation length, diet, brain volume and scansoriality) when analyses differed only in their spatial resolution. However, predictors differed when analyses also varied in their temporal extent. Macroecological findings about extinction risk can, thus, inform conservation at smaller scales, but they risk misidentifying threatened species if differences in temporal extent are not recognised.