Biology subjects

Burton, C.

Publications and source records attributed to Burton, C..

9 recordsLinked to original sources

bioRxiv2026

Sharing the trail: recreation effects on bear behaviour in a Canadian Rocky Mountain Park

Humans are profoundly reshaping the natural world. These changes are giving rise to complex and mutually risky dynamics between people and large carnivores. In protected areas across North America, bears (Ursus sp.) face rapidly rising recreation pressures that can alter their use of the landscape, either displacing them from high-quality habitats or drawing them into human-wildlife conflicts through habituation or attraction to anthropogenic resources. However, disentangling responses to recreation from other drivers can be difficult because human activity covaries with environmental and seasonal processes that also shape bear activity. We leveraged the partial closure of the popular Berg Lake Trail in Mount Robson Park, British Columbia, Canada, to investigate whether black (Ursus americanus) and grizzly bears (Ursus arctos) showed fear, attraction or neutral behavioural responses to varying recreation levels across multiple spatiotemporal scales. To understand both anticipatory responses to predictable patterns of human activity, and reactive responses to hiker events, we used detections from 43 camera traps over two years (July 2023-June 2025). We compared weekly habitat use, daily activity patterns, and direct responses to hikers (using Avoidance-Attraction Ratios; AARs) among camera sites and between open and closed sections of the trail. Our results revealed that both bear species exhibited patterns consistent with fear responses, while some black bear behaviours were also consistent with attraction responses. Both kinds of responses reflect anticipatory strategies rather than reactionary behaviours (i.e., no AAR effect). Neither species avoided recreation spatially at the weekly scale: black bears were detected more at site-weeks with greater recreation intensity, while grizzly bears were consistently detected more at sites closer to hiking trails. However, both species used daily temporal partitioning to avoid direct encounters with humans. These findings demonstrate scope for human-bear coexistence when recreation levels are managed to be moderate and predictable, and bears have sufficient space to segregate from humans during peak times. Thus, successful coexistence will hinge on co-adaptation by both bears and people. Understanding how recreation influences bear behaviour, and the spatiotemporal scale at which that occurs, is critical for guiding effective adaptive management aimed at fostering human-bear coexistence in high-traffic protected areas.

ecology↗

bioRxiv2026

The effect of outdoor recreation on mammal habitat use and diversity revealed by COVID-19 closures

The rising demand for outdoor recreation worldwide may be undermining the conservation objectives of protected areas (PAs). We leveraged a natural experiment, in which two adjacent PAs were closed to the public for different durations during the COVID-19 pandemic. Using detections from 39 camera traps in Joffre Lakes and Garibaldi Parks, Canada, from 2020-2022, we examined how recreation influenced mammal habitat use and diversity. Bayesian regression showed weak evidence that, when recreation was higher, detections declined for black bear, mule deer, and marten, while detections of bobcat and hoary marmot shifted closer to trails. Accumulation curves revealed that species richness and diversity were higher in the closed vs. open PA in 2020 (mean differences of -5.04 for richness and -0.33 for Shannon diversity). However, diversity did not decline consistently despite increases in recreation in 2021 and 2022. Notably, several rare species were only detected in the lower-recreation PA, suggesting they may be filtered out of the higher-recreation PA. This emphasizes the need for long-term monitoring to detect delayed and cumulative effects of recreation on mammal communities. Given growing global pressures on biodiversity, we urge PA managers to prioritize adaptive management to assess and balance outdoor recreation with conservation goals.

ecology↗

bioRxiv2024

Vulnerable caribou and moose populations display contrasting responses to mountain pine beetle outbreaks and management.

O_LIRising global temperatures and changing landscape conditions have led to widespread mountain pine beetle (MPB) outbreaks in western North America. Extensive management has been implemented in response, via forest harvesting and prescribed burning. However, the impacts of MPB and MPB-management on ungulate populations, particularly caribou and moose, remain poorly studied. Given the differing specialisations of these species (caribou are habitat specialists, moose are generalists), their responses to these disturbances may vary. This could, in turn, lead to unintended, indirect effects (e.g., disturbance-mediated apparent competition, whereby increased moose presence results in increased predator presence, with resultant caribou declines). Unravelling these responses is crucial for informing MPB management and ensuring that applied actions do not exacerbate adverse effects. C_LIO_LIWe assessed the effects of early-stage MPB-infestation, harvest, and fire, on habitat selection by caribou (boreal and central mountain designatable units) and moose in west-central Alberta. We built resource selection functions and functional response models using GPS collar data collected 3-5 years after MPB infestation and found that responses varied between species. C_LIO_LICaribou had complex seasonal responses to MPB, generally avoiding areas with more MPB disturbance in winter but using them in summer. Caribou typically avoided harvested and burned areas, though this was dependent on the overall degree of disturbance within their ranges. In contrast, moose had positive responses to both MPB and burned areas year-round. C_LIO_LIThese findings suggest that MPB may negatively impact long-term winter habitat availability for threatened caribou populations, but may have positive impacts on moose habitat. However, moose use of MPB-impacted areas could further affect caribou by contributing to disturbance-mediated apparent competition. C_LIO_LISynthesis and applications: The negative impacts of forest harvest and burning on caribou suggests that less intensive actions are required for MPB management within caribou ranges.. While moose selectively used harvested and burned areas, it is possible that they may have adverse responses to cumulative disturbance over time. As caribou and moose responded to MPB soon after infestation, ongoing monitoring is required to detect MPB early and facilitate proactive management, though further study is needed to determine the most effective actions. C_LI

ecology↗

bioRxiv2023

Brain Metabolic Network Covariance and Aging in a Mouse Model of Alzheimer's Disease

INTRODUCTIONAlzheimers disease (AD), the leading cause of dementia worldwide, represents a human and financial impact for which few effective drugs exist to treat the disease. Advances in molecular imaging have enabled assessment of cerebral glycolytic metabolism, and network modeling of brain region have linked to alterations in metabolic activity to AD stage. METHODSWe performed 18F-FDG Positron Emission Tomography (PET) imaging in 4-, 6-, and 12-month-old 5XFAD and littermate controls (WT) of both sexes and analyzed region data via brain metabolic covariance analysis. RESULTS5XFAD model mice showed age related changes glucose uptake relative to WT mice. Analysis of community structure of covariance networks was different across age and sex, with a disruption of metabolic coupling in the 5XFAD model. DISCUSSIONThe current study replicates clinical AD findings and indicates that metabolic network covariance modeling provides a translational tool to assess disease progression in AD models. RESEARCH IN CONTEXTO_ST_ABSSYSTEMATIC REVIEWC_ST_ABSThe authors extensively reviewed literature (e.g., PubMed), meeting abstracts, and presentations on approaches to evaluate brain network analysis in animal models. Based on the available data, there were clear gaps in our understanding of how metabolic networks change with disease progression at the preclinical phase, thus limiting the utility of these measures for clinical comparison in Alzheimers disease (AD). INTERPRETATIONOur findings indicate that employing metabolic covariance modeling in mouse models of AD and littermate controls of both sexes with age provides a mechanism to evaluate brain changes in network function which align closely with previous clinical stages of AD. Moreover, utilizing open-source clinical tools from the Brain Connectivity Toolbox (BCT), we demonstrated that brain networks reorganize with AD progression at multiple levels, and these changes are consistent with previous reports in human AD studies. FUTURE DIRECTIONSThe open-source framework developed in the current work provides valuable tools for brain metabolic covariance modeling. Such tools can be used in both preclinical and clinical settings and they enable more direct translation of preclinical imaging studies to those in the clinic. When matched with an appropriate animal model, genetics, and/or treatments, this study will enable assessment of in vivo target engagement, translational pharmacodynamics, and insight into potential treatments of AD.

neuroscience↗

bioRxiv2022

Use of object detection in camera trap image identification: assessing a method to rapidly and accurately classify human and animal detections for research and application in recreation ecology

Camera traps are increasingly used to answer complex ecological questions. However, the rapidly growing number of images collected presents technical challenges. Each image must be classified to extract data, requiring significant labour, and potentially creating an information bottleneck. We applied an object-detection model (MegaDetector) to camera trap data from a study of recreation ecology in British Columbia, Canada. We tested its performance in detecting humans and animals relative to manual image classifications, and assessed efficiency by comparing the time required for manual classification versus a modified workflow integrating object-detection with manual classification. We also evaluated the reliability of using MegaDetector to create an index of human activity for application to the study of recreation impacts to wildlife. In our application, MegaDetector detected human and animal images with 99% and 82% precision, and 95% and 92% recall respectively, at a confidence threshold of 90%. The overall time required to process the dataset was reduced by over 500%, and the manual processing component was reduced by 840%. The index of human detection events from MegaDetector matched the output from manual classification, with a mean 0.45% difference in estimated human detections across site-weeks. Our test of an open-source object-detection model showed it performed well in partially classifying a camera trap dataset, significantly increasing processing efficiency. We suggest that this tool could be integrated into existing camera trap workflows to accelerate research and application by alleviating data bottlenecks, particularly for surveys processing large volumes of human images. We also show how the model and workflow can be used to anonymize human images prior to classification, protecting individual privacy. Impact StatementWe developed and tested a workflow for classifying camera trap images that integrated an existing object-detection model with manual image classification. Our workflow demonstrates an increase in efficiency of 500% over manual labelling, and additionally includes a method to anonymize human images prior to archiving and classification. We provide an example of the application of these tools to ease data processing, particularly for studies focused on recreation ecology which record high volumes of human images. Data lags due to processing delays have the potential to result in sub-optimal conservation decisions, which may be alleviated by accelerated processing. To our knowledge, this is the first in-depth assessment of the practical application of such technology to real world workflows focused on human detections.

ecology↗

bioRxiv2021

Selective Modulator of Nuclear Receptor PPARy with Reduced Adipogenic Potential Ameliorates Experimental Nephrotic Syndrome

BackgroundGlomerular disease, often manifesting as nephrotic syndrome (NS) with high proteinuria, can be refractory to standard treatment and is typically associated with hypoalbuminemia, hypercholesterolemia and hypercoagulopathy. We hypothesized that the nuclear receptor PPAR{gamma} can be selectively modulated using a novel partial agonist, GQ-16, to gain therapeutic advantage over traditional PPAR{gamma} agonists (e.g. thiazolidinediones) for the treatment of glomerular disease. MethodsNephropathy was induced with puromycin amino-nucleoside (PAN) in Wistar rats and treated with Pioglitazone (Pio) or GQ-16. Plasma, serum, and urine chemistries were performed, and kidneys, glomeruli, liver, and white adipose tissue (WAT) were harvested. Lipid accumulation and adipogenic gene expression were measured in adipocytes. ResultsPAN-induced proteinuria was significantly reduced with Pio to 64% of PAN-value. It was reduced robustly with GQ-16 to 81% of PAN, which was comparable to controls. While both GQ-16 and Pio restored glomerular Nphs1 and hepatic Pcsk9 expression and reduced hypercholesterolemia, GQ-16 also restored glomerular Nrf2, and reduced hypoalbuminemia and hypercoagulopathy. Furthermore, RNA-seq analysis identified both common and distinct restored glomerular genes downstream of Pio and GQ-16. Pio but not GQ-16 significantly induced aP2 (fatty acid binding protein) in adipocytes and in WAT. Pio induced more lipid accumulation than GQ-16 in differentiated adipocytes. Both, Pio and GQ-16 induced insulin sensitizing adipokines in WAT with varying degrees. ConclusionsSelective modulation of PPAR{gamma} by a partial agonist, GQ-16, is more advantageous than pioglitazone in reducing proteinuria and NS associated co-morbidities, while reducing the adipogenic side-effects conferred by traditional PPAR{gamma} full agonists. Translational StatementThe authors have previously reported that type-II diabetes drugs, thiazolidinediones (PPAR{gamma} agonists), also provide beneficial effects in reducing podocyte and glomerular injury. However, these drugs are associated with adverse effects such as weight gain, and their effects on glomerular disease-associated features are largely unexplored. Their current findings demonstrate that PPAR{gamma} can be selectively modulated by its partial agonist, GQ-16, which reduces proteinuria and improves nephrotic syndrome (NS) with reduced side-effects typically conferred by thiazolidinediones. These findings not only deepen our molecular understanding of the role of PPAR{gamma} in glomerular disease and underscore the potential for partial agonists of PPAR{gamma}, such as GQ-16 as a treatment modality for NS, but also lend the possibility of its potential benefits in diabetic nephropathy.

molecular biology↗

bioRxiv2020

The effect of heat on SARS-CoV-2 viability and RNA integrity as determined by plaque assay, virus culture and real-time RT-PCR

The effect of heat on SARS-CoV-2/England/2/2020 viability was assessed by plaque assay and virus culture. Heating to 56{degrees}C and 60{degrees}C for 15, 30 and 60 minutes led to a reduction in titre of between 2.1 and 4.9 log10 pfu/ml but complete inactivation was not observed. At 80{degrees}C plaques were observed after 15 and 30 minutes of heating, however after 60 minutes viable virus was only detected following virus culture. Heating to 80{degrees}C for 90 minutes and 95{degrees}C for 1 and 5 minutes resulted in no viable virus being detected. At 56{degrees}C and 60{degrees}C significant variability between replicates was observed and the titre often increased with heat-treatment time. Nucleic acids were extracted and tested by RT-PCR. Sensitivity of the RT-PCR was not compromised by heating to 56{degrees}C and 60{degrees}C. Heating to 80{degrees}C for 30 minutes or more and 95{degrees}C for 1 or 5 minutes however, resulted in an increase of at least three Ct values. This increase remained constant when different dilutions of virus underwent heat treatment. This indicates that high temperature heat inactivation of clinical samples prior to nucleic acid extraction could significantly affect the ability to detect virus in clinical samples from patients with lower viral loads by RT-PCR.

microbiology↗

bioRxiv2020

Characterization of Mice Bearing Humanized Androgen Receptor Genes (h/mAr) Varying in Polymorphism Length

The androgen receptor (AR) is known for masculinization of behavior and brain. To better understand the role that AR plays, mice bearing humanized Ar genes with varying lengths of a polymorphic N-terminal glutamine (Q) tract were created (Albertelli et al 2006). The length of the Q tract is inversely proporitional to AR activity. Biological studies of the Q tract length may also provide a window into potential AR contributions to sex-biases in disease risk. Here we take a multi-pronged approach to characterizing AR signaling effects on brain and behavior in mice using the humanized Ar Q tract model. We first map effects of Q tract length on regional brain anatomy, and consider if these are modified by gonadal sex. We then test the notion that spatial patterns of anatomical variation related to Q tract length could be organized by intrinsic spatiotemporal patterning of AR gene expression in the mouse brain. Finally, we test influences of Q tract length on four behavioral tests. Altering Q tract length led to neuroanatomical differences in a non-linear dosage-dependent fashion. Gene expression analyses indicated that adult neuroanatomical changes due to Q tract length are only associated with neurodevelopment (as opposed to adulthood). No significant effect of Q tract length was found on the behavior of the three mouse models. These results indicate that AR activity differentially mediates neuroanatomy and behavior, that AR activity alone does not mediate sex differences, and that neurodevelopmental processes are associated with spatial patterns of volume changes due to Q tract length in adulthood. They also indicate that androgen sensitivity in adulthood does not directly lead to autism-related behaviors or neuroanatomy, although neurodevelopmental processes may play a role earlier. Further study into sex differences, development, other behaviors, and other sex-specific mechanisms are needed to better understand AR sensitivity, neurodevelopmental disorders, and the sex difference in their prevalence.

neuroscience↗

bioRxiv2020

Effects of scent lure on camera trap detections vary across mammalian predator and prey species

Camera traps are a unique survey tool used to monitor a wide variety of mammal species. Camera trap (CT) data can be used to estimate animal distribution, density, and behaviour. Attractants, such as scent lures, are often used in an effort to increase CT detections; however, the degree which the effects of attractants vary across species is not well understood. We investigated the effects of scent lure on mammal detections by comparing detection rates between 404 lured and 440 unlured CT stations sampled in Alberta, Canada over 120 day survey periods between February and August in 2015 and 2016. We used zero-inflated negative binomial generalized linear mixed models to test the effect of lure on detection rates for a) all mammals, b) six functional groups (all predator species, all prey, large carnivores, small carnivores, small mammals, ungulates), and c) four varied species of management interest (fisher, Pekania pennanti; gray wolf, Canis lupus; moose, Alces alces; and Richardsons ground squirrel; Urocitellus richardsonii). Mammals were detected at 800 of the 844 CTs, with nearly equal numbers of total detections at CTs with (7110) and without (7530) lure, and variable effects of lure on groups and individual species. Scent lure significantly increased detections of predators as a group, including large and small carnivore sub-groups and fisher specifically, but not of gray wolf. There was no effect of scent lure on detections of prey species, including the small mammal and ungulate sub-groups and moose and Richardsons ground squirrel specifically. We recommend that researchers explicitly consider the variable effects of scent lure on CT detections across species when designing, interpreting, or comparing multi-species surveys. Additional research is needed to further quantify variation in species responses to scent lures and other attractants, and to elucidate the effect of attractants on community-level inferences from camera trap surveys.

ecology↗