The Department of Biological Sciences has an expanding research base, which, in addition to providing leading researchers of national and international standing in these areas, most importantly underpins the delivery of teaching. Research in Biological Sciences at Chester can be divided into three broad groups of expertise, namely Animal Behaviour and Conservation, Food Nutrition and Health, and Stress and Disease.

Recent Submissions

  • Pain in Sheep

    McLennan, Krista M.; University of Chester (CABI Publishing, 2024-01-19)
    Pain in sheep can occur for a variety of reasons, including disease, injury, and naturally through parturition. Sheep, as a prey species, do not overtly express pain making it challenging for owners and veterinarians to recognise and thus effectively treat pain. By observing facial expressions, it is possible to recognise and quantify the pain a sheep may be experiencing. This enables the provision of treatment and the prevention of any further suffering. Information © The Author 2024
  • Automatic detection of indris songs using convolutional neural networks

    Valente, Daria; Ravaglia, Davide; Ferrario, Valeria; De Gregorio, Chiara; Carugati, Filippo; Raimondi, Teresa; Cristiano, Walter; Torti, Valeria; von Hardenberg, Achaz; Ratsimbazafy, Jonah; et al. (European Acoustics Association, 2024-01-17)
  • How Useful Are Existing Protocols in the Quick Assessment of the Welfare of Semi-Feral Horses? Pilot Study on Konik Polski Horses Living in the Forest Sanctuary

    Górecka-Bruzda, Aleksandra; Siemieniuch, Marta; Lansade, Léa; Stanley, Christina R.; Polish Academy of Sciences; Institut Français du Cheval et d’Equitation; University of Chester (MDPI, 2023-12-19)
    Scientifically validated and standardised methods for the evaluation of the welfare of free-living horses are urgently needed by both the owners and managers of these populations and those responsible for implementing national welfare legislation. The aim of the study was to test the feasibility and usefulness of two welfare protocols that could be applied to semi-feral populations: a prototype of welfare assessment template (WAT) for Carneddau semi-feral ponies and the IFCE/INRAE Horse Welfare Protocol. Additionally, the body condition scale designed by Henneke (BCS-H) was employed. The study took place in July/August 2022 and April 2023 to evaluate the welfare of a pilot population of nineteen semi-feral Konik polski horses. The horses scored high or satisfactory under indicators across both protocols; only body condition scores were significantly lower in early spring (BCS-WAT: 1.11 ± 0.57; BCS-H: 3.84 ± 1.17) than in the summer (BCS-WAT: 1.58 ± 0.61; BCS-H: 5.63 ± 1.01). Our study confirmed the feasibility of utilising most of the WAT and IFCE/INRAE welfare indicators in semi-feral horses. Some adaptations, such as considering validation of scales, positive welfare indicators and animals’ free-choice of conditions, have been suggested for future in-field application.
  • Coupled information networks drive honeybee (Apis mellifera) collective foraging

    Hasenjager, Matthew; Hoppitt, William; Cunningham‐Eurich, Iona; Franks, Victoria; Leadbeater, Ellouise; University of Tennessee; University of London; Natural History Museum, London; University College London; University of Chester (Wiley, 2023-11-27)
    Collective behaviour by eusocial insect colonies is typically achieved through multiple communication networks that produce complex behaviour at the group level but often appear to provide redundant or even competing information. A classic example occurs in honeybee (Apis mellifera) colonies, where both the dance communication system and robust scent‐based mechanisms contribute to the allocation of a colony's workforce by regulating the flow of experienced foragers among known food sources. Here we analysed social connectivity patterns during the reactivation of experienced foragers to familiar feeding sites to show that these social information pathways are not simply multiple means to achieve the same end but intersect to play complementary roles in guiding forager behaviour. Using artificial feeding stations, we mimicked a natural scenario in which two forager groups were simultaneously collecting from distinct patches containing different flowering species. We then observed the reactivation of these groups at their familiar feeding sites after interrupting their foraging. Social network analysis revealed that temporarily unemployed individuals interacted more often and for longer with foragers that advertised a familiar versus unfamiliar foraging site. Due to such resource‐based assortative mixing, network‐based diffusion analysis estimated that reactivation events primarily resulted from interactions among bees that had been trained to the same feeding station and less so from different‐feeder interactions. Both scent‐ and dance‐based interactions strongly contributed to reactivation decisions. However, each bout of dance‐following had an especially strong effect on a follower's likelihood of reactivation, particularly when dances indicated locations familiar to followers. Our findings illustrate how honeybee foragers can alter their social connectivity in ways that are likely to enhance collective outcomes by enabling foragers to rapidly access up‐to‐date information about familiar foraging sites. In addition, our results highlight how reliance on multiple communication mechanisms enables social insect workers to utilise flexible information‐use strategies that are robust to variation in the availability of social information.
  • Non‐invasive sampling reveals low mitochondrial genetic diversity for an island endemic species: The critically endangered Grenada Dove Leptotila wellsi

    Peters, Catherine; Geary, Matthew; Hosie, Charlotte; Nelson, Howard; Rusk, Bonnie; Muir, Anna; University of Chester; University of Cambridge; Grenada Dove Conservation Programme (Wiley Open Access, 2023-11-23)
    As an island endemic with a decreasing population, the critically endangered Grenada Dove Leptotila wellsi is threatened by accelerated loss of genetic diversity resulting from ongoing habitat fragmentation. Small, threatened populations are difficult to sample directly but advances in molecular methods mean that non‐invasive samples can be used. We performed the first assessment of genetic diversity of populations of Grenada Dove by (a) assessing mtDNA genetic diversity in the only two areas of occupancy on Grenada, (b) defining the number of haplotypes present at each site and (c) evaluating evidence of isolation between sites. We used non‐invasively collected samples from two locations: Mt Hartman (n = 18) and Perseverance (n = 12). DNA extraction and PCR were used to amplify 1751 bps of mtDNA from two mitochondrial markers: NADH dehydrogenase 2 (ND2) and Cytochrome b (Cyt b). Haplotype diversity (h) of 0.4, a nucleotide diversity (π) of 0.00023 and two unique haplotypes were identified within the ND2 sequences; a single haplotype was identified within the Cyt b sequences. Of the two haplotypes identified, the most common haplotype (haplotype A = 73.9%) was observed at both sites and the other (haplotype B = 26.1%) was unique to Perseverance. Our results show low mitochondrial genetic diversity and clear evidence for genetically isolated populations. The Grenada Dove needs urgent conservation action, including habitat protection and potentially augmentation of gene flow by translocation in order to increase genetic resilience and diversity with the ultimate aim of securing the long‐term survival of this critically endangered species.
  • Monitoring wildlife population trends with sample counts: a case study on the Alpine ibex (Capra ibex)

    Panaccio, Matteo; Brambilla, Alice; Bassano, Bruno; Smith, Tessa; von Hardenberg, Achaz; University of Chester; Alpine Wildlife Research Centre, Gran Paradiso National Park; University of Zurich (Wiley Open Access, 2023-11-06)
    Monitoring population dynamics is of fundamental importance in conservation but assessing trends in abundance can be costly, especially in large and rough areas. Obtaining trend estimations from counts performed in only a portion of the total area (sample counts) can be a cost‐effective method to improve the monitoring and conservation of species difficult to count. We tested the effectiveness of sample counts in monitoring population trends of wild animals, using as a model population the Alpine ibex Capra ibex in the Gran Paradiso National Park (Italy), both with computer simulations and using historical count data collected over the last 65 years. Despite sample counts failed to correctly estimate the true population abundance, sampling half of the target area could reliably monitor the trend of the target population. In case of strong changes in abundance, an even lower proportion of the total area could be sufficient to identify the direction of the population trend. However, when there is a high yearly trend variability, the required number of samples increases and even counting in the entire area can be ineffective to detect population trends. The effect of other parameters, such as which portion of the area is sampled and detectability, was lower, but these should be tested case by case. Sample counts could therefore constitute a viable alternative to assess population trends, allowing for important, cost‐effective improvements in the monitoring of wild animals of conservation interest.
  • Technical validation and a comparison of two methods to quantify individual levels of glucocorticoids in Alpine marmot hair

    Doss, Elina M.; Jouffroy, Mathilde; Rey, Benjamin; Cohas, Aurélie; von Hardenberg, Achaz; Smith, Tessa E.; University of Chester; Université de Lyon (Elsevier, 2023-10-13)
    Quantification of cortisol concentration in hair has become a promising conservation tool for non-invasive monitoring of “stress” in wild populations, yet this method needs to be carefully validated for each species. The goals of the study were: • Immunologically validate two methods (study 1 and 2 respectively) to extract and quantify cortisol in the hair of wild Alpine marmots. • Compare the amount of cortisol extracted from hair samples using two methods i.e. cut into fine pieces (study 1) and hair samples pulverized using a ball mill (study 2). • Determine the extent to which methods in study 2 could provide individual specific hair cortisol (HC) measures when samples were taken from the same body location. Within and between individual variations in HC levels were examined from multiple hair samples from 14 subjects in study 2. We evaluated if inter-individual variations in HC levels could be explained by sex and age. At least twice the amount of cortisol was obtained per g/hair when samples were pulverized in a ball mill prior to extraction compared to when cut into pieces. Our methods demonstrated intra-individual consistency in HC at a given time point: inter-individual variation in HC was three times larger than within individual variance. Sex and age did not impact HC levels.
  • Sample size assessments for thermal physiology studies: An R package and R Shiny application

    van Steenderen, Clarke J. M.; Sutton, Guy F.; Owen, Candice A.; Martin, Grant D.; Coetzee, Julie A.; Rhodes University; University of Chester; University of the Free State (The Royal Entomological Society, 2023-08-17)
    Required sample sizes for a study need to be carefully assessed to account for logistics, cost, ethics and statistical rigour. For example, many studies have shown that methodological variations can impact the critical thermal limits (CTLs) recorded for a species, although studies on the impact of sample size on these measures are lacking. Here, we present ThermalSampleR; an R CRAN package and Shiny application that can assist researchers in determining when adequate sample sizes have been reached for their data. The method is particularly useful because it is not taxon specific. The Shiny application offers a user‐friendly interface equivalent to the package for users not familiar with R programming. ThermalSampleR is accompanied by an in‐built example dataset, which we use to guide the user through the workflow with a fully worked tutorial.
  • Genetic polymorphisms in the serotonin, dopamine and opioid pathways influence social attention in rhesus macaques (Macaca mulatta)

    Howarth, Emmeline; Szott, Isabelle D.; Witham, Claire L.; Wilding, Craig S.; Bethell, Emily J.; Liverpool John Moores University; University of Chester; Centre for Macaques, Harwell Institute, Medical Research Council, Salisbury; (Public Library of Science, 2023-08-02)
    Behaviour has a significant heritable component; however, unpicking the variants of interest in the neural circuits and molecular pathways that underpin these has proven difficult. Here, we present a comprehensive analysis of the relationship between known and new candidate genes from identified pathways and key behaviours for survival in 109 adult rhesus macaques (Macaca mulatta). Eight genes involved in emotion were analysed for variation at a total of nine loci. Genetic data were then correlated with cognitive and observational measures of behaviour associated with wellbeing and survival using MCMC-based Bayesian GLMM in R, to account for relatedness within the macaque population. For four loci the variants genotyped were length polymorphisms (SLC6A4 5-hydroxytryptamine transporter length-polymorphic repeat (5-HTTLPR), SLC6A4 STin polymorphism, Tryptophan 5-hydroxylase 2 (TPH2) and Monoamine oxidase A (MAOA)) whilst for the other five (5-hydroxytryptamine receptor 2A (HTR2A), Dopamine Receptor D4 (DRD4), Oxytocin receptor (OXTR), Arginine vasopressin receptor 1A (AVPR1a), Opioid receptor mu(μ) 1 (OPRM1)) SNPs were analysed. STin genotype, DRD4 haplotype and OXTR haplotype were significantly associated with the cognitive and observational measures of behaviour associated with wellbeing and survival. Genotype for 5-HTTLPR, STin and AVPR1a, and haplotype for HTR2A, DRD4 and OXTR were significantly associated with the duration of behaviours including fear and anxiety. Understanding the biological underpinnings of individual variation in negative emotion (e.g., fear and anxiety), together with their impact on social behaviour (e.g., social attention including vigilance for threat) has application for managing primate populations in the wild and captivity, as well as potential translational application for understanding of the genetic basis of emotions in humans.
  • Parental breeding decisions and genetic quality predict social structure of independent offspring

    Franks, Victoria; Thorogood, Rose; Brekke, Patricia; University of Chester; University of Helsinki; Zoological Society of London (Wiley, 2023-07-03)
    Across the animal kingdom, newly-independent juveniles form social associations that influence later fitness, mate choice, and gene flow, but little is known about the ontogeny of social environments, particularly in wild populations. Here we test whether associations among young animals form randomly, or are influenced by environmental or genetic conditions established by parents. Parents’ decisions determine natal birth sites, which could affect who independent young initially encounter; secondly, mate choice determines genetic condition (e.g. inbreeding) of young and the parental care they receive, which can affect sociability. However, genetic and environmental factors are confounded unless related offspring experience different natal environments. Therefore, we used a long-term genetic pedigree, breeding records, and social network data from three cohorts of a songbird with high extra-pair paternity (hihi, Notiomystis cincta) to disentangle (1) how nest location and relatedness contribute to association structure once juveniles disperse away from birth sites, and (2) if juvenile and/or parental inbreeding predicts individual sociability. We detected positive spatial autocorrelation: hihi that fledged closer by were more likely to associate even after dispersing, irrespective of genetic relatedness. Juvenile inbreeding did not predict sociability, but those raised by more inbred fathers formed more, stronger, associations, which did not depend on whether that male was the genetic parent or not. These results suggest that the natal environment created by parents, rather than focal genetic condition, establishes the foundation for social associations. Overall, we highlight how social inheritance may play an important role in population dynamics and evolutionary potential in wild animals.
  • Machine Learning for collagen peptide biomarker determination in the taxonomic identification of archaeological fish remains

    Baker, Andrew; Harvey, Virginia L.; Buckley, Michael; University of Chester; University of Manchester (Elsevier, 2023-04-22)
    Species identification of archaeofaunal remains can be informative of changing local and global ecosystems, as well as how we interacted with them in the past. However, with the vast majority of assemblages being dominated by morphologically indeterminate specimens, methods of biomolecular species identification are becoming more popular, such as the protein fingerprint-based identification approach known as ZooMS (Zooarchaeology by Mass Spectrometry). As larger datasets are being produced, Machine Learning techniques such as those using Random Forest algorithms have been considered to expedite the identification process. However, it has proven difficult to extract meaningful biomarkers from these processes alone and so far only tackled for mammals. Here, we introduce a novel approach based on the principles of the ID3 algorithm for biomarker identification from ZooMS spectral databases, focussing on archaeological fish remains from Europe and the Caribbean. We show that the tool is highly effective at generating comprehensible lists of family- and genus-level biomarkers. At family-level identification, the average sensitivity across five families of fish was ∼0.9, where a specificity of 1 would indicate a greatly effective algorithm that outperforms both traditional Random Forest and Naïve Bayes approaches; at the genus level the mean sensitivity reduced to ∼0.8 across the nine genera tested. However, some anomalous matches were produced, with accuracy dropping when distinguishing between genera of the same family, such as Epinephelus and Mycteroperca belonging to the Serranidae. Therefore, while this tool has value in rapidly producing lists of biomarkers and can efficaciously identify new ZooMS fingerprints based on those markers, it indicates that manual intervention remains a requirement at finer taxonomic resolutions.
  • A multidisciplinary approach to estimating wolf population size for long-term conservation

    Marucco, Francesca; Boiani, Maria V.; Dupont, Pierre; Milleret, Cyril; Avanzinelli, E.; Pilgrim, Kristine; Schwartz, A. Michael K.; von Hardenberg, Achaz; Perrone, S.; Friard, Olivier; et al. (Wiley, 2023-06-01)
    The wolf (Canis lupus) is among the most controversial of wildlife species. Abundance estimates are required to inform public debate and policy decisions, but obtaining them at biologically relevant scales is challenging. We developed a system for comprehensive population estimation across the Italian Alpine Region (100,000 km ), involving 1,513 trained operators representing 160 institutions. This extensive network allowed for coordinated genetic sample collection and landscape-level spatial capture-recapture analysis transcending administrative boundaries. We produced the first estimates of key parameters for wolf population status assessment including wolf abundance (952 individuals, 95% CrI: 816-1120), the number of reproductive units (135 packs, 95% CrI: 112-165), and the proportion of mature individuals (33-45%). The results also provided reliable information about the monitoring effort, thereby overcoming an important limitation of citizen-science data. This is an effective approach for promoting wolf-human coexistence based on wolf abundance monitoring, and a tool for endorsing large-scale harmonized conservation practices. This article is protected by copyright. All rights reserved. [Abstract copyright: This article is protected by copyright. All rights reserved.]
  • Human-Wildlife Conflict in Golden Monkeys (Cercopithecus mitis kandti) of the Volcanoes National Park, Rwanda

    Ndayishimiye, Eric; Eckardt, Winnie; Fletcher, Alison W.; University of Chester; Dian Fossey Gorilla Fund (Springer, 2023-05-04)
    Human-wildlife conflict, in particular crop-foraging, challenges conservationists worldwide. Endangered golden monkeys (Cercopithecus mitis kandti) are frequent crop-foragers around Volcanoes National Park (VNP), Rwanda. To evaluate the impact of crop-foraging behaviour on monkeys and farmers, we interviewed 45 farmers near VNP using a structured questionnaire and organised a workshop for local and regional actors to discuss mitigation measures. To investigate differences in monkey behaviour when foraging inside versus outside VNP, and to inform mitigation strategies, we collected ad libitum behavioural data from one habituated golden monkey group for 11 weeks. We tested the feasibility of a taste aversion technique to deter monkeys, by placing chilli-laced potatoes in harvested potato fields adjacent to the study group’s home range, but found that experimental aversion techniques were logistically challenging. Of 38 farmers, 95% experienced potato loss to monkeys and 36% of 44 farmers threw objects at/chased monkeys in the previous farming season. Farmers and workshop participants judged the most effective way to mitigate crop-foraging to be through improvement of existing crop-guarding. Behavioural observations indicated increased vigilance behaviour and decreased social behaviour when in farmland. Monkeys (N=9) that visited the experimental area avoided chilli-laced potatoes but continued to forage on nearby crops. In conclusion, our results indicate that crop-foraging can negatively impact farmers' livelihoods and attitudes and can increase vigilance behaviour of monkeys. Our multi-faceted approach enabled the involvement of a wide range of stakeholders, highlighted the urgent need to improve existing management measures and explored alternatives to facilitate positive coexistence between monkeys and farmers.
  • A Mozambican marine protected area provides important habitat for vulnerable pelagic sharks

    Murie, Calum; Lebrato, Mario; Lawrence, Andrew; Brown, James; Gavard, Livia; Bowles, Karen R.; Jije, Mauro G.; Dicken, Matt; Oliver, Simon P.; University of Chester; Bazaruto Centre for Scientific Studies ; KwaZulu Natal Sharks Board; University of Plymouth (Nature Research, 2023-04-20)
    Pelagic sharks play key roles in marine ecosystems, but are increasingly threatened by human extraction, habitat degradation and mismanagement. We investigated the use of protected and unprotected coastal habitats by bull (Carcharhinus leucas) and oceanic blacktip (Carcharhinus limbatus) sharks in southern Mozambique. Five INNOVASEA VR2W-69 kHz acoustic receivers were positioned in the Bazaruto Archipelago National Park (BANP) as well as one to the south of the park’s boundaries. Seven receivers were also deployed 250 km south in the Inhambane estuary and on reef sites off Praia de Tofo. Twelve bull, and six oceanic blacktip sharks, were fitted with INNOVASEA V16 acoustic tags, which generated 933 detections of bull and 12,381 detections of oceanic blacktip sharks over a period of 1391 days. A generalised additive model was used to estimate the effects of seven spatiotemporal and environmental parameters on the frequency of each species’ detections. In general, calculated residency indices were highest around the locations monitored in the BANP and one unprotected location off Tofo. Both species were more abundant across the monitored sites, during the summer when water temperatures were ~ 27 °C, when the moon was < 50% illuminated, and when the tide was rising. Detections coincided with each species’ reproductive season indicating that both species may be reproductively active in the BANP region. Oceanic blacktip sharks were largely resident and so fisheries management may significantly benefit their population(s) around certain reef habitats in the BANP. The low residency and seasonal detections of bull sharks indicates that they may be transient and so effective conservation may require coordination between regional fisheries managers.
  • New records of benthic foraminifera in the surface sediments of the Little Neston saltmarsh of the Dee Estuary in England, UK.

    Kennedy, Ruth; Biro, Mariann; Oliver, Simon P.; University of Chester; University of Liverpool
    We investigated the community composition of benthic foraminifera in surface sediments taken from 8 sample stations in the Little Neston salt marsh, in England (UK). Constrained cluster analyses determined a zonation pattern in the spatial variability, composition, and richness of benthic foraminiferal species relative to the tidal frame that was constrained by elevation and salinity (as a secondary influence) in our study area. Stations across the high and mid marshes contained a high proportion of agglutinated foraminifera, whereas the low marsh and mudflats were dominated by calcareous species, which is consistent with reports from other latitudinally similar salt marsh habitats. The exceptionally low proportion of morphological abnormalities in the foraminiferal tests that we sampled suggests that the Little Neston salt marsh is a pristine, unpolluted environment. New micropaleontological occurrence records for the Little Neston salt marsh are presented, which will be useful for reconstructing Holocene relative sea-level changes and contribute to global databases: PANGAEA® Data Publisher.
  • New records of benthic foraminifera in the surface sediments of the Dulas Bay saltmarsh in North Wales, UK

    Kennedy, Ruth; Biro, Mariann; Marret-Davis, Fabienne; Oliver, Simon P.; University of Chester; University of Liverpool
    We investigated the community composition of benthic foraminifera in surface sediments taken from 14 sample sites in the saltmarshes of the Dulas Bay Estuary in North Wales (UK). Constrained cluster analyses determined that the composition and richness of benthic foraminiferal species in our study area were dominated by calcareous species in mud and sandy sediments and that their vertical distribution was constrained by elevation, which is consistent with reports from other latitudinally similar saltmarsh habitats. The exceptionally low proportion of morphological abnormalities in the foraminiferal tests that we sampled suggests that the Dulas Bay Estuary is a pristine unpolluted environment. New micropaleontological occurrence records for the Dulas Bay Estuary are presented, which will be useful for reconstructing Holocene relative sea-level changes and contribute to global databases: PANGAEA® Data Publisher.
  • The Social and Reproductive Challenges Faced by Free-Roaming Horse (Equus caballus) Stallions

    Górecka-Bruzda, Aleksandra; Jaworska, Joanna; Stanley, Christina R.; University of Chester; Polish Academy of Sciences (MDPI, 2023-03-24)
    In captivity, intact male horses, due to their sexual drive, are usually socially isolated from other horses. This lifestyle strongly contrasts with that experienced by horses living in free-roaming, feral, or semi-feral conditions, where adult stallions have several roles in their social group, with successful reproduction being their primary drive. Reproductive skew in wild populations is high; many stallions will fail to reproduce at all, while others achieve high levels of reproductive success, siring a large number of foals. Successful stallions are those with particular characteristics and abilities that facilitate harem formation and tenure, allowing them to successfully take over a harem or establish a new one, protect mares from rival stallions, employ appropriate social behaviour to maintain group cohesion, and avoid kin-mating, for example through kin recognition mechanisms. Whilst the life of free-living stallions is far from stress-free, they retain ancestral adaptations to selection pressures (such as predation and competition) exhibited by their natural environment over thousands of years. Here, we discuss the challenges faced by free-living horse stallions, the roles they play in social groups, and their resulting social needs. By understanding these pressures and how stallions react to them, we highlighted the importance of the social environment for the stallion. It is hoped that a better understanding of wild stallions’ lives will lead to their needs being more clearly met in captivity, reducing stereotypical behaviour and improving welfare.
  • Extrinsic and intrinsic factors affecting the activity budget of alpine marmots (Marmota marmota)

    Ferrari, Caterina; Pasquaretta, Cristian; Caprio, Enrico; Ranghetti, Luigi; Rolando, Antonio; Bertolino, Sandro; Bassano, Bruno; von Hardenberg, Achaz; University of Turin; Alpine Wildlife Research Centre, Gran Paradiso National Park; Université Paul Sabatier; Consiglio Nazionale delle Ricerche; University of Pavia; University of Chester (Springer, 2022-03-15)
    Extrinsic and intrinsic factors may influence the activity budget of wild animals, resulting in a variation in the time spent in different activities among populations or individuals of the same species. In this study, we examined how extrinsic and intrinsic factors affect the behaviour of the alpine marmot (Marmota marmota), a hibernating social rodent inhabiting high-elevation prairies in the European Alps. We collected behavioural observations during scan sampling sessions on marked individuals at two study sites with different environmental characteristics. We used Bayesian hierarchical multinomial regression models to analyse the influence of both intrinsic (sex and age-dominance status) and extrinsic (environmental and climatic variables) factors on the above-ground activity budget. Marmots spent most of their time above ground foraging, and were more likely to forage when it was cloudy. Extrinsic factors such as the site, period of the season (June, July–August, and August–September), and time of the day were all related to the probability of engaging in vigilance behaviour, which reaches its peak in early morning and late afternoon and during July, the second period included in the study. Social behaviours, such as affiliative and agonistic behaviours, were associated mostly with sex and age-dominance status, and yearlings were the more affiliative individuals compared to other status. Overall, our results suggest that in alpine marmots, intrinsic factors mostly regulate agonistic and affiliative behaviours, while extrinsic factors, with the unexpected exception of temperature, affect the probabilities of engaging in all types of behavioural categories.
  • See you in spring: overwinter survival is higher than post summer in the Alpine marmot

    Ferrari, Caterina; Cerri, Jacopo; Rolando, Antonio; Bassano, Bruno; von Hardenberg, Achaz; Bertolino, Sandro; University of Turin; Gran Paradiso National Park; University of Primorska; University of Chester (Taylor & Francis, 2023-01-09)
    Animal species living in highly seasonal environments developed different strategies to cope with the periodical drastic change of environmental conditions. Hibernating mammals survive the winter season by reducing their activity and metabolism, and by centring their activities during the favourable season. Thus, the demography of these species depends upon both hibernating and active periods. In this study, we explored the apparent survival of Alpine marmots monitored between 2007 and 2018 in the North-Western Italian Alps. We fit Cormack-Jolly-Seber (CJS) models to quantify changes in the apparent survival and capture probability of marmots, after the hibernation phase and at the end of the summer. Apparent survival after winter almost reached 100% and it was higher than post-summer survival. Moreover, while post-summer apparent survival remained almost stable over lifetime, with a slight increase with age, characterised however by wide confidence intervals, overwinter survival decreased with age, especially after 6 years of age. No temporal trends, nor changes between areas at different elevations, were found. We suggest that these results arise from a combination of climatic conditions, predation pressure and social dynamics, which is a pivotal feature of this species and cannot be ignored when considering population dynamics of Alpine marmots. This study provides evidence of a higher survival in the hibernating mammals of the Alpine ecosystem, the Alpine marmot, compared to the survival of individuals during the summer season, providing the first evidence of different seasonal survival in this species. High overwinter survival in Alpine marmot
  • Changes in foraging behaviour suggest competition between wild and domestic ungulates: Guanaco and domestic sheep in southern Patagonia

    Lancaster, Alex; Corti, Paulo; Fernández, Tomás; Moraga, Claudio A.; Radic-Schilling, Sergio; von Hardenberg, Achaz; University of Chester; Universidad Austral de Chile; Centro de Estudios del Cuaternario de Fuego-Patagonia y Antártica (Fundación CEQUA); University of Florida; Universidad de Magallanes (Wiley, 2022-04-09)
    Previous attempts to address the presence of interspecific competition between domestic livestock and wild ungulates have focused largely on habitat or dietary overlaps. Although overlaps in habitat or diet create opportunities for competition to occur between species, competition only results from such overlap if it affects one or both species negatively. Less attention has been afforded to possible behavioural modifications induced in wildlife by competition with domestic livestock. Here, we investigated the effects of the presence of livestock on feeding behaviour of guanaco (Lama guanicoe) in southern Patagonia, using focal sampling of individuals during foraging bouts, with instantaneous scan samples to estimate group behavioural budgets. We recorded guanaco bite and step rates, used as proxies of foraging intake and selectivity, from four different study sites over eight consecutive seasons. We also estimated sheep and guanaco densities per site, along with vegetation biomass availability. As in other ungulates, bite rates of guanaco appear to be highly flexible and generally increased with vegetation biomass availability. However, as sheep densities and thus additional grazing pressure increased, guanaco foraging strategy compensated by increasing bite rates when foraging vegetation was scarce, indicating further likelihood of competition. Additionally, scan samples indicated that the probability of guanaco feeding occurring at any one time was higher in areas shared with domestic sheep compared to national parks, suggesting guanaco have to focus more on feeding than other behaviours when sheep are present.

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