Most cited article - PubMed ID 35175823
Big-data approaches lead to an increased understanding of the ecology of animal movement
Pharmaceutical contaminants reaching natural aquatic ecosystems can affect fish behaviour, modifying activity patterns, foraging behaviour and antipredator responses. While laboratory-based studies can offer key insights, assessing the ecological relevance of these findings requires field-based approaches. Therefore, we examined the effects of oxazepam, a widely prescribed anxiolytic drug, on the behaviour of a cyprinid fish (the common roach, Rutilus rutilus) in the wild, combining slow-release exposure implants with continuous tracking via acoustic telemetry. To add ecological realism, we created a landscape of fear with an uneven distribution of resources (macrophytes) and exposure to predators (pike, Esox lucius), additionally testing the effects of the drug on roach habitat selection and predator-prey interactions. Fish exposed to the drug showed an increased swimming activity and speed, but exhibited a more constrained spatial distribution in the pond, favouring areas with higher refuge availability. Both exposed and unexposed fish modified their habitat use in the presence of predators. Exposed fish appeared to get closer to the predators when these were caged, but not when predators were free-roaming. Our findings highlight the importance of considering ecological context to understand how pharmaceuticals affect fish behaviour, which is crucial for assessing risks at population and ecosystem levels.
- Keywords
- behaviour, benzodiazepine, fish, home range, oxazepam, predation, telemetry,
- MeSH
- Anti-Anxiety Agents * adverse effects MeSH
- Water Pollutants, Chemical * adverse effects toxicity MeSH
- Behavior, Animal * drug effects MeSH
- Cyprinidae * physiology MeSH
- Ecosystem * MeSH
- Oxazepam * adverse effects MeSH
- Predatory Behavior drug effects MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Anti-Anxiety Agents * MeSH
- Water Pollutants, Chemical * MeSH
- Oxazepam * MeSH
The use of electronic tags has significantly advanced our understanding of wild animal behaviour and physiology. However, traditional tagging methods often require capturing and restraining or sedating animals, which causes stress and may potentially affect data quality during acclimatization. Inspired by plant burs, we propose a novel 'bur-tagging' system to attach tags without capture or restraint. We outline a framework for bur-tagging, detailing the design and key considerations for its success. This includes the influence of tagging site location and animal neophobia on the likelihood of tagging over time, strategies to target specific species, and methods to improve tag placement accuracy. The choice of adhesive mechanism and application force are discussed as critical factors for effective attachment. Preliminary trials highlight animal reactions to inactive tagging systems, demonstrating ways to minimize stress and increase tagging efficiency. Field tests on domestic animals and wild canids in Greece suggest that bur-tagging is a viable alternative to conventional methods. While still in development, bur-tagging has the potential to deploy advanced electronic tags on wild animals with reduced stress and greater ethical consideration, offering a promising tool for wildlife research. This innovative approach bridges biology and technology to address challenges in animal tagging.
- Keywords
- animal capture, animal restraint, biologging, biotelemetry, bur-tagging,
- Publication type
- Journal Article MeSH
Who conducts biological research, where they do it and how results are disseminated vary among geographies and identities. Identifying and documenting these forms of bias by research communities is a critical step towards addressing them. We documented perceived and observed biases in movement ecology, a rapidly expanding sub-discipline of biology, which is strongly underpinned by fieldwork and technology use. We surveyed attendees before an international conference to assess a baseline within-discipline perceived bias (uninformed perceived bias). We analysed geographic patterns in Movement Ecology articles, finding discrepancies between the country of the authors' affiliation and study site location, related to national economics. We analysed race-gender identities of USA biology researchers (the closest to our sub-discipline with data available), finding that they differed from national demographics. Finally, we discussed the quantitatively observed bias at the conference, to assess within-discipline perceived bias informed with observational data (informed perceived bias). Although the survey indicated most conference participants as bias-aware, conversations only covered a subset of biases. We discuss potential causes of bias (parachute-science, fieldwork accessibility), solutions and the need to evaluate mitigatory action effectiveness. Undertaking data-driven analysis of bias within sub-disciplines can help identify specific barriers and move towards the inclusion of a greater diversity of participants in the scientific process.
- Keywords
- academic conference, diversity, equity, journal authorship, parachute science, representation,
- MeSH
- Ecology * MeSH
- Humans MeSH
- Movement MeSH
- Research Personnel * MeSH
- Bias MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Predicting animal movements and spatial distributions is crucial for our comprehension of ecological processes and provides key evidence for conserving and managing populations, species and ecosystems. Notwithstanding considerable progress in movement ecology in recent decades, developing robust predictions for rapidly changing environments remains challenging. To accurately predict the effects of anthropogenic change, it is important to first identify the defining features of human-modified environments and their consequences on the drivers of animal movement. We review and discuss these features within the movement ecology framework, describing relationships between external environment, internal state, navigation and motion capacity. Developing robust predictions under novel situations requires models moving beyond purely correlative approaches to a dynamical systems perspective. This requires increased mechanistic modelling, using functional parameters derived from first principles of animal movement and decision-making. Theory and empirical observations should be better integrated by using experimental approaches. Models should be fitted to new and historic data gathered across a wide range of contrasting environmental conditions. We need therefore a targeted and supervised approach to data collection, increasing the range of studied taxa and carefully considering issues of scale and bias, and mechanistic modelling. Thus, we caution against the indiscriminate non-supervised use of citizen science data, AI and machine learning models. We highlight the challenges and opportunities of incorporating movement predictions into management actions and policy. Rewilding and translocation schemes offer exciting opportunities to collect data from novel environments, enabling tests of model predictions across varied contexts and scales. Adaptive management frameworks in particular, based on a stepwise iterative process, including predictions and refinements, provide exciting opportunities of mutual benefit to movement ecology and conservation. In conclusion, movement ecology is on the verge of transforming from a descriptive to a predictive science. This is a timely progression, given that robust predictions under rapidly changing environmental conditions are now more urgently needed than ever for evidence-based management and policy decisions. Our key aim now is not to describe the existing data as well as possible, but rather to understand the underlying mechanisms and develop models with reliable predictive ability in novel situations.
- Keywords
- biologging, conservation, human‐modified landscapes, modelling, movement ecology,
- MeSH
- Anthropogenic Effects * MeSH
- Models, Biological MeSH
- Ecosystem MeSH
- Animal Migration * MeSH
- Animal Distribution * MeSH
- Conservation of Natural Resources * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
In war and conflict zones, the jamming of Global Navigation Satellite System (GNNS) signals by military forces disrupts the tracking of tagged animals, and has increased in frequency following the recent escalation of conflicts in Eastern Europe and the Middle East. Such disruption to data collection strongly hampers research into the protection and conservation of endangered animals.
- Publication type
- Journal Article MeSH
Pharmaceutical contaminants have spread in natural environments across the globe, endangering biodiversity, ecosystem functioning, and public health. Research on the environmental impacts of pharmaceuticals is growing rapidly, although a majority of studies are still conducted under controlled laboratory conditions. As such, there is an urgent need to understand the impacts of pharmaceutical exposures on wildlife in complex, real-world scenarios. Here, we validate the performance of slow-release pharmaceutical implants-a recently developed tool in field-based ecotoxicology that allows for the controlled chemical dosing of free-roaming aquatic species-in terms of the accumulation and distribution of pharmaceuticals of interest in tissues. Across two years, we directly exposed 256 Atlantic salmon (Salmo salar) smolts to one of four pharmaceutical treatments: clobazam (50 μg g-1 of implant), tramadol (50 μg g-1), clobazam and tramadol (50 μg g-1 of each), and control (0 μg g-1). Fish dosed with slow-release implants containing clobazam or tramadol, or their mixture, accumulated these pharmaceuticals in all of the sampled tissues: brain, liver, and muscle. Concentrations of both pharmaceuticals peaked in all tissues at 1 day post-implantation, before reaching relatively stable, slowly declining concentrations for the remainder of the 30-day sampling period. Generally, the highest concentrations of clobazam and tramadol were detected in the liver, followed by the brain and then muscle, with observed concentrations of each pharmaceutical being higher in the single-exposure treatments relative to the mixture exposure. Taken together, our findings underscore the utility of slow-release implants as a tool in field-based ecotoxicology, which is an urgent research priority given the current lack of knowledge on the real-world impacts of pharmaceuticals on wildlife.
- Publication type
- Journal Article MeSH
Pharmaceutical pollution poses an increasing threat to global wildlife populations. Psychoactive pharmaceutical pollutants (e.g. antidepressants, anxiolytics) are a distinctive concern owing to their ability to act on neural pathways that mediate fitness-related behavioural traits. However, despite increasing research efforts, very little is known about how these drugs might influence the behaviour and survival of species in the wild. Here, we capitalize on the development of novel slow-release pharmaceutical implants and acoustic telemetry tracking tools to reveal that exposure to environmentally relevant concentrations of the benzodiazepine pollutant temazepam alters movement dynamics and decreases the migration success of brown trout (Salmo trutta) smolts in a natural lake system. This effect was potentially owing to temazepam-exposed fish suffering increased predation compared with unexposed conspecifics, particularly at the river-lake confluence. These findings underscore the ability of pharmaceutical pollution to alter key fitness-related behavioural traits under natural conditions, with likely negative impacts on the health and persistence of wildlife populations.
- Keywords
- behaviour, chemical, ecology, global change, survival, telemetry,
- MeSH
- Water Pollutants, Chemical * toxicity MeSH
- Lakes * MeSH
- Animal Migration * MeSH
- Trout * physiology MeSH
- Psychotropic Drugs pharmacology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Water Pollutants, Chemical * MeSH
- Psychotropic Drugs MeSH
Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4-7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals.
- MeSH
- Herbivory physiology MeSH
- Behavior, Animal physiology MeSH
- Animals, Wild physiology MeSH
- Species Specificity MeSH
- Ecosystem * MeSH
- Humans MeSH
- Locomotion physiology MeSH
- Mammals * physiology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
BACKGROUND: Animal migrations are periodic and relatively predictable events, and their precise timing is essential to the reproductive success. Despite large scientific effort in monitoring animal reproductive phenology, identification of complex environmental cues that determine the timing of reproductive migrations and temporal changes in the size of reproductive aggregations in relation to environmental variables is relatively rare in the current scientific literature. METHODS: We tagged and tracked 1702 individuals of asp (Leuciscus aspius), a large minnow species, and monitored with a resolution of one hour the size of their reproductive aggregations (counts of sexes present at the breeding grounds standardized by the sum of individuals in the season) over seven breeding seasons using passive integrated transponder tag systems. We examined the size of reproductive aggregations in relation to environmental cues of day number within a reproductive season (intra-year seasonality), water temperature, discharge, hour in a day (intra-day pattern), temperature difference between water and air, precipitation, atmospheric pressure, wind speed and lunar phase. A generalized additive model integrating evidence from seven breeding seasons and providing typical dynamics of reproductive aggregations was constructed. RESULTS: We demonstrated that all environmental cues considered contributed to the changes in the size of reproductive aggregations during breeding season, and that some effects varied during breeding season. Our model explained approximately 50% of the variability in the data and the effects were sex-dependent (models of the same structure were fitted to each sex separately, so that we effectively stratified on sex). The size of reproductive aggregations increased unimodally in response to day in season, correlated positively with water temperature and wind speed, was highest before and after the full moon, and highest at night (interacting with day in a season). Males responded negatively and females positively to increase in atmospheric pressure. CONCLUSION: The data demonstrate complex utilization of available environmental cues to time reproductive aggregations in freshwater fish and their interactions during the reproductive season. The study highlights the need to acquire diverse data sets consisting of many environmental cues to achieve high accuracy of interpretation of reproductive timing.
- Keywords
- Fish movement, Long-term monitoring, Migration, Phenology, Reproductive behaviour, Weather,
- Publication type
- Journal Article MeSH