RSS 1.0Biological Sciences
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.
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Massive declines and local recoveries: First range-wide assessment spotlights ending egg-taking as key to the survival of the Macrocephalon maleo (Maleo)The communally nesting, Critically Endangered Macrocephalon maleo (Maleo) is an iconic species endemic to Sulawesi, Indonesia, yet despite decades of legal protection its populations have declined sharply across its range. We performed the first-ever range-wide field survey of Maleo nesting grounds, visiting 122 known and identifying 58 previously unrecorded sites, collecting physical and biological data and interviewing local informants at each. We added information from the literature for another 48 abandoned sites, documenting a total of 228 historic and current nesting grounds. We then constructed a profile of historic and current populations and area of occupancy (AOO) units across Sulawesi. Between 1980 and 2019, 55% of active nesting grounds became inactive, and all but one of the 94 sites that remained active in 2019 had fewer birds. In 2019, 83% of all nesting grounds active in 1980 were either completely abandoned or just barely active, hosting no more than 2 pairs day–1 at peak season. However, conservation efforts have also produced significant recoveries and discoveries. Our survey increased the range of described landscape types where Maleo nest from 2 to 4, and documented Maleo nesting in previously unrecorded places, including artificially created sandy areas. As the Maleo’s maximum travel distance beyond nesting grounds is unknown, we applied a cost-based approach using possible maximum travel distances of 25, 40, and 50 km to define AOO “Units” that represent a set of separate range-wide subpopulations defined by each maximum travel distance. Between 1980 and 2019, the overall AOO declined by 37%, 26%, and 19% at maximum travel distances of 25, 40, and 50 km, respectively; the number of active nesting grounds in each isolated unit declined by 58%, 78%, and 80%, respectively; and fragmentation (i.e., the total number of units) increased by 5%, 100%, and 125%, respectively. In some areas, Maleo may be changing their behavior in response to egg predation by humans. Ending egg-taking has now clearly been shown to produce Maleo increases in multiple locations and is crucial to range-wide recovery of the species.
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PhyBaSE: A Bayesian structural equation model approach to causal inference in phylogenetic comparative analysesOne of the main limitations of phylogenetic comparative analyses is that associations between traits can only be interpreted as correlations. Here, we present a novel Bayesian structural equation model (PhyBaSE) which allows us to disentangle direct from indirect relationships among variables to propose potential causal hypotheses while accounting for phylogenetic non‐independence. Compared with the existing maximum‐likelihood based approach, PhyBaSE models are more flexible, allowing the inclusion of trait and phylogenetic uncertainty, as well as non‐continuous variables. To facilitate the application of the method, we provide worked examples, data and code. We exemplify the method both with simulated as well as empirical data. Our analyses with simulated data indicate that PhyBaSE models have higher power than classic Phylogenetic Path Analysis to discriminate between competing models. As an example of PhyBaSE using empirical data, we revisit different hypotheses proposed to explain the relationship between relative brain size and group size in Bovids. Our results challenge the previously supported social brain hypothesis and provide support for an allometric effect of body size on social group size and an effect of brain size on life span, as predicted by the cognitive buffer hypothesis. The flexibility of PhyBaSE models will allow researchers to explore more complex hypotheses on the evolution of behavioural, ecological and life history traits at a macroevolutionary level and how these are linked to anthropogenic drivers of biodiversity loss and extinction, taking full advantage of the increasing number of publicly available species‐specific datasets.
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Macaque mothers’ responses to the deaths of their infantsAlthough it is understood that all humans grieve the death of close social partners, little empirical research has addressed animals’ responses to death. In this study, we collected quantitative data on the behaviour of 11 bereaved rhesus macaque (Macaca mulatta) mothers at Cayo Santiago to the natural deaths of their infants and matched, non-bereaved controls. Our research focused on behavioural signs of grief, including loss of appetite, lethargy, increased stress and social withdrawal, highlighting that such responses are documented in the human literature, but could be found in mammalian taxa. Using mixed models, we found that, contrary to prediction, bereaved mothers spent less time resting than the non-bereaved control females in the first two weeks after their infants’ deaths. There were no other behavioural markers of grief. We conclude that mothers showed a short-term behavioural response to their bereavement that does not match human’s prolonged ‘despair’ grief. We propose that mothers’ behavioural responses might be a form of ‘protest’ grief, as is seen in primate infants when separated from mothers and in humans, or do not grieve. We hope to advance the field of comparative thanatology by providing a framework and novel predictions for future studies in this area.
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Population dynamics of the Rodrigues fruit bat (Pteropus rodricensis): An analysis of long-term island wide bat count dataThe Rodrigues fruit bat (Pteropus rodricensis) is an insular Old-World fruit bat endemic to the Island of Rodrigues. The Mauritian Wildlife Foundation implemented a population monitoring program in 1974 and an estimate of less than 80 individuals was recorded in 1979. Following conservation efforts of reforestation of native flora, the population has experienced a steady increase, subject to decreases in numbers after severe cyclones. A standardized methodology was applied in 2016 creating a dataset suitable for population modelling and statistical analysis. The most recent population census (2022) revealed that the population has remained stable at around 20,000 individuals for the last 5 years. This study uses Generalised Linear Mixed Models (GLMMs) to analyse 17 years of population monitoring data in order to identify the climatic factors potentially driving the population trend. We identified that the strongest factors driving changes in the population numbers were linked to resource availability. Most notable were annual precipitation levels, which had a positive relationship with population size (β=1.745, P<0.001), and cyclones, specifically relating to cyclonic strength, which was negatively related with the population size (β=-0.205, P<0.0001). This study also critically analyses the population count methodology and offers recommendations and suggestions for future research to be conducted on the species.
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Developing and validating attention bias tools for assessing trait and state affect in animals: A worked example with Macaca mulattaAttention bias is a new approach to assessing animal affect that has shown promising results in several animal species. It describes a tendency to preferentially attend to emotional compared to neutral cues and is influenced by underlying affect. It is important in the early days of this new field that we develop widely utilisable methods and incorporate lessons from the human literature from which tasks are adapted. This fundamental knowledge is critical to the development of standardised and sensitive tools, and the validation of experimental protocols to ensure best practice. Here, we describe protocols for two preferential-looking attention bias tasks. Study 1 involved a manual task using freely available low-cost materials. Study 2 used an automated task requiring specialist equipment and programming, but presumably less prone to noisy data. Tasks were tested with 109 socially housed rhesus macaques, Macaca mulatta, who had been trained to sit by a target, but received no other training. Tasks involved showing animals emotional face pairs (threat-neutral), and subsequent blind coding of video for duration of looking at either face. Three measures of social attention were examined: time spent looking at the threat face (THR), total time looking at the threat-neutral face pair overall (TL), and attention bias difference score (ABD) calculated as time spent looking at the neutral face subtracted from time spent looking at the threat face. Based on the human literature and early primate work, the influence of five potential confounding factors on attention was assessed: trial number, stimulus ID, previous testing experience, time of day and visual field to which the threat face was presented; as were several life history factors: sex, age, and social rank. Both tasks revealed stable individual differences in baseline social attention (THR and TL: effect sizes = 0.15−0.31; repeatabilities = 0.12−0.26; suggesting sensitivity to trait affect), but not ABD (which may be more sensitive to brief shifts in emotion state). All potential confounding factors had a significant effect on at least one measure of social attention. For a subset of monkeys who took part in both Study 1 and Study 2 several years apart (n = 18), there was significant reproducibility between tasks for all three measures (R = 0.15−0.63), supporting an argument for stable individual differences in baseline attention bias, and validating the two tasks for measuring the same trait. The attention bias method shows promise for further development of standardised protocols with animals. We provide framework and recommendations for future method development.
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Dysfunctional tetraspanin 7 (TSP-7) in Caenorhabditis elegans promotes; increases in average life- & health-span, stress-induced survival and motilityCaenorhabditis elegans (C. elegans) tetraspanin-7 (TSP-7) protein is an orthologue of the Human tetraspanin CD63, which has recently been shown to be a negative regulator of autophagy. In this study a mutant strain of wild-type (WT) C. elegans (tm5761) with a 352 bp deletion in the tsp-7 gene, was studied. A polyclonal antibody was raised to a peptide sequence present only in the wild-type strain (N2). This antibody cross-reacted with the protein of the correct molecular weight (MW) in the WT lysate, but not in the tm5761, confirming the absence of a functional TSP-7 in this strain. From life-span studies, the tm5761 strain had a higher average survival age of 23.3 ± 0.6, compared to 20.1 ± 0.8 days for WT, although the absolute life-span was not statistically different. This indicates that the mutant tm5761 strain has an increased physiological health-span. Survival studies undertaken at 37 °C, showed a decrease in survival levels, with complete death of the WT occurring after 3 h of exposure, whereas the tm5761 strain was more robust (i.e. 25% survival after 3 h). Sub-lethal osmotic stress caused by increased sodium chloride (NaCl) concentrations was investigated by observing stress-related motility, such as frequency of coiling and reversing. These results showed that the tm5761 strain was more motile at higher concentrations of NaCl than the WT. These findings suggest that, like CD63, TSP-7 could be acting as a negative regulator of autophagy; therefore, the tm5761 strain likely has increased basal autophagy. This would explain its; increased, mean life- and health-span, motility under stress, and improved thermotolerance.
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Integrating human and wildlife dynamics in co‐occurrence modellingIn shared environments, where different species interact depending on overlapping resources, complex interspecific interactions emerge, with human activities impacting these dynamics and influencing wildlife abundance and distribution. In the Alps, the presence of multiple species of ungulates, such as roe deer and red deer, and a predator, the wolf, creates a web of spatial and behavioral interactions in an area where farming, hunting and tourism have persisted over time, with tourism recently experiencing a substantial growth. Accounting for these multiple interactions, we modelled the co‐occurrence probabilities of roe deer, red deer and wolves in an area of the Maritime Alps using data derived from 60 camera traps. We applied multi‐species occupancy models to investigate (i) the role of species co‐occurrences in explaining the occupancy of model species across the landscape, (ii) the role of human presence and activities on species occupancy and (iii) the potential effect of the hunting season on the species detection probabilities. Among the identified species, roe deer reported the highest frequency of recorded events and were the most widespread species. We provided important evidence of interspecific dependence, revealing that pairwise interactions among species had a greater impact than only considering individual environmental effects. We documented that the setting of cameras on trails increased the likelihood of detecting wolves but decreased the likelihood of detecting ungulates. Most importantly, the hunting season significantly reduced the likelihood of capturing roe deer, while having no effect on either red deer or wolves. Our results confirmed the relevance of including prey, predators, and human dynamics as a whole. Since the sharing of habitat makes human activities significantly important in defining predator–prey mechanisms, our insights are particularly relevant for defining solutions to optimize human‐wildlife coexistence, especially in a highly anthropogenic system such as Europe.
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Elasmobranchs and the Inshore Reefs of Southern MozambiqueThe coastal waters off southern Mozambique host a diverse community of elasmobranchs. The complexity of studying sharks and rays in remote locations means that limited research attention focusses on its marine environment. As the region is famed for its coastal reefs and the diversity of its elasmobranch species, a novel opportunity was presented to study elasmobranch species that have become rare in most other regions. This thesis aims to investigate the relationship between elasmobranch species and coastal reef habitat in southern Mozambique. This aim is addressed by investigating the frequency with which elasmobranch species visit reef systems and by comparing this with the environmental and biological conditions on the reefs. A reef camera trap was deployed 60 times on four reefs to record elasmobranch visits and to estimate the relative abundance of each reef’s fish and coral communities. SCUBA-based transects (n = 738) were conducted on 18 reefs in the same region to count elasmobranchs and measure environmental parameters that influence the presence of elasmobranchs on the reefs. Two large Carcharhinus sharks were observed in low numbers during video and SCUBA observations. To monitor their interactions with regional reefs, 18 acoustic tags were fitted to Carcharhinus limbatus and Carcharhinus leucas individuals. The sharks were tracked on 13 omnidirectional acoustic receivers positioned on reefs throughout the Inhambane province of southern Mozambique. The community composition of reef fishes appeared to influence the species of elasmobranch that frequented each survey area. Sharks visited reefs with the most abundant piscivorous fish life, which we determined to be linked to foraging opportunities. Small-bodied stingrays were only observed visiting shallow reefs near intertidal sand flats. Pelagic rays (e.g. Mobula spp.) were most often observed while cleaning on reefs that were proximate to their foraging grounds.Elasmobranch abundance on reefs was found to vary across several spatiotemporal and environmental parameters, resulting in patterns of reef use across various temporal scales. Most elasmobranch species became abundant on reefs during the summer, and tide, water temperature, and moon illumination were found to be strong predictors of their presence and abundance. Closely related species were similar in their responses to the measured environmental and spatiotemporal parameters and these species visited the same reefs with specific biological characteristics. Reducing pressures on the reefs that elasmobranch species rely on, and eliminating the extraction of elasmobranchs around these reefs, could benefit the populations of vulnerable elasmobranchs off the coast of southern Mozambique.
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SP3 protocol optimised for foodcrust protein extraction from archaeological cooking vesselsA SP3-based protocol developed for the extraction of proteins from charred organic residues (foodcrust) found on cooking vessels. This protocol is to prepare samples for MALDI-ToF MS and LC-MS/MS analysis. We recommend starting with a batch size of 2-10 samples, and including flanking negative controls (blanks) to test for any downstream contamination.
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Validating the underpinnings of water corticosterone measurement for aquatic amphibiansBACKGROUND: Good animal welfare is important ethically but also to ensure animals provide valid scientific models. Despite thousands of amphibians in research laboratories there is minimal quantitative evidence pertaining to their management and welfare. This study validated methods to non-invasively measure corticosterone, the amphibian ‘stress’ hormone, from tank water to provide a robust and reliable welfare assessment tool. METHODS: We report experiments (A) that evaluate parameters linked to the performance of our biochemical extraction methods for waterborne corticosterone and, importantly, associated sampling procedures. We evaluate appropriate sampling water type, sampling vessel, filtration methods, potential degradation of waterborne corticosterone over time and the impact of sampling procedures on animal corticosterone levels. We wanted to determine sampling parameters that yielded the least background corticosterone and had minimum negative impact on the animals. The second series of experiments (B) evaluated parameters linked to the biology of Xenopus, including the influence of circadian rhythm, sex and snout-vent length on waterborne corticosterone levels, since fundamental knowledge of a species’ biology is essential for designing robust experiments and in the interpretation of the results. RESULTS: We propose collecting corticosterone samples in deionised water in either plastic or glass containers. The filtering process does not impact the amount of corticosterone measured in the water sample. Levels of corticosterone collected in the water change over a 48-hr period so we advocate standardising time from hormone collection to storage at - 20 °C. Repeated transfer of frogs to sampling containers does not increase corticosterone, suggesting our methods are not cumulatively stressful. Corticosterone levels were not impacted by circadian phase, sex or snout-vent length. CONCLUSION: We have developed and validated robust methods to quantify waterborne corticosterone. We hope they provide a template for researchers wishing to develop methods to measure waterborne corticosterone in aquatic amphibians.
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Pain in mammals: physiology, management and assessmentPain is a sensory and emotional experience that has significant consequences on an animal’s welfare. To improve animal welfare, there is a need to prevent as well as manage pain, but we cannot manage what we cannot measure. In this chapter we highlight pains complexity, with the experience affected by multiple factors, including age, sex, personality and previous experience and remains a critical issue in veterinary care. We provide details on the physiological mechanism of pain and show how with this knowledge we can provide appropriate treatment to manage pain effectively. We acknowledge that many animals are however still experiencing pain. Even with the acceptance of animal sentience, recognizing, assessing and evaluating pain in animals is difficult. We briefly detail physiological indicators of pain such as heart rate and cortisol but acknowledge that there are difficulties in their use within veterinary clinics, for example. Behavioral indicators of pain can range from change in eating behavior to aggression. We discuss that there are many tools currently available to identify and assess pain, but that many require extensive training, are time consuming to carry out, and tend to measure the long-term impact on general biological functioning rather than pain per se. We highlight the more recent increase of the use of facial expression scales as an alternate tool that can accurately recognize and assess pain in a variety of species and can indicate what an animal is feeling at that moment in time. We also briefly touch on the use of technology such as Artificial Intelligence and Computer Vision as a novel tool to assess pain, providing a much more objective assessment. There is an urgent need for tools that can effectively and directly detect and measure pain in animals and further research in the use of computer-based modelling will be key for the future.
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An examination of interspecific competition using observations in behaviour and physiology: A case study of Guanaco (Lama guanicoe) and domestic sheep (Ovis aries) in Chilean PatagoniaThe introduction of a new species to ecosystems can result in competition between native species and the introduced, with adaptations that may allow coexistence, through resource facilitation or partitioning, unable to evolve, given the short co-evolutionary time period. Consequently, in cases where livestock species have been introduced to a new system, competitive interactions between native and domestic species have been directly instigated, with interspecific competition between sympatric, free living ungulates and domestic livestock becoming an increasing concern for conservationists. Understanding the specific ways and mechanisms in which this competition manifests is critical for informing conservation management, both of wild species, and domestic livestock. Throughout this thesis, I examine the case study of wild guanaco (Lama guanicoe) and domestic sheep (Ovis aries), in the Patagonian Steppe ecosystem of Southern Chile, a system in which competition has been demonstrated as highly probable. Two key elements in guanaco-sheep competition were investigated, to determine whether competitive effects manifest in (1) foraging behaviour, by examining the effects of sheep presence on the behavioural changes in guanaco, and (2) physiology, by examining the effects of sheep presence on guanaco separately for cortisol and testosterone. (1) Guanaco bite rates generally increased with vegetation biomass availability. However, when sheep were present in high densities, the pattern reversed, with guanaco bite rates decreasing with vegetation abundance. Additionally, the probability of guanaco feeding occurring at any one time was shown to be higher in areas shared with domestic sheep than in national parks, where sheep are absent. Both results suggest guanaco prioritise feeding behaviours at the expense of other behaviours, where sheep are present. (2) Sheep presence did not predict either the cortisol or testosterone profiles of guanaco. Instead, cortisol concentrations were influenced by the group number and composition (number of adults and juveniles). Conversely, testosterone content was influenced mainly by the specific Age-Sex Class (social group) of the individual.
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A new double observer‐based census framework to improve abundance estimations in mountain ungulates and other gregarious species with a reduced effortEstimating animal abundance has a key role to play in ecology and conservation, but survey methods are always challenged by imperfect detection. Among the techniques applied to deal with this issue, Double Observer (DO) is increasing in popularity due to its cost‐effectiveness. However, the effort of using DO for surveying large territories can be significant. A DO‐based survey method that allows accurate abundance estimations with reduced effort would increase the applicability of the method. This would have positive effects on the conservation of species which are challenging to survey such as mountain ungulates. We used computer simulations based on real data and a field test to assess the reliability of the DO and of a new proposed survey procedure, the Double Observer Adjusted Survey (DOAS). DOAS is based on total block counts adjusted with some DO surveys conducted in a proportion of the total area only. Such DO surveys are then used to estimate detection probability with a mark‐recapture‐derived approach. We found that full DO is much more accurate than simple block counts for abundance estimations. DOAS is a less demanding alternative to full DO and can produce comparable abundance estimates, at the cost of a slightly lower precision. However, in the DOAS overall detectability has to be estimated within a sufficient number of sites (around a quarter of the total) to obtain a higher precision and avoid large overestimations. Practical implications. DO methods could increase the reliability of abundance estimations in mountain ungulates and other gregarious species. Full DO in particular could allow researchers to obtain unbiased estimations with high precision and its usage is therefore suggested instead of block counts in wildlife monitoring. Given the high costs of full DO, the DOAS procedure could be a viable and cost‐effective survey strategy to improve abundance estimates when resources are scarce.
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The thermal physiology of Lysathia sp. (Coleoptera: Chrysomelidae), a biocontrol agent of parrot’s feather in South Africa, supports its successThe establishment success of biocontrol agents originating from tropical regions is often limited by climate when introduced in temperate regions. However, the flea beetle, Lysathia sp. (Coleoptera: Chrysomelidae), a biocontrol agent of Myriophyllum aquaticum (Vell.) Verdc. (Haloragaceae) in South Africa, is an effective agent in regions where other biocontrol agents of tropical aquatic weeds have failed due to winter-induced mortality. The development (degree-day model) and thermal tolerance (critical thermal minimum/maximum [CTmin/max] and lower/upper lethal limits [LLT/ULT50]) of Lysathia sp. were investigated to explain this success. The model predicted that Lysathia sp. could complete 6 to 12 generations per year in the colder regions of the country. The lower threshold for development (t0) was 13.0 °C and thermal constant (K) was 222.4 days, which is considerably lower than the K values of other biocontrol agents of aquatic weeds in South Africa. This suggests that above the temperature threshold, Lysathia sp. can develop faster than those other species and complete multiple life cycles in the cooler winter months, allowing for rapid population growth and thus improving M. aquaticum control. Furthermore, the CTmin of Lysathia sp. was 2.3 ± 0.2 °C and the CTmax was 49.0 ± 0.5 °C. The LLT50 was calculated as ∼ −7.0 °C and the ULT50 as ∼ 43.0 °C. These wide tolerance ranges and survival below freezing show why Lysathia sp. has established at cool sites and suggest that it may be a suitable agent for other cold countries invaded by M. aquaticum.
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Cape vultures (Gyps coprotheres) on camera: Assessing the behaviour of a vulnerable, colonially nesting raptor with temperature and time of day at nest sites in KwaZulu-Natal, South AfricaThe Cape Vulture (Gyps coprotheres) has the smallest range of any vulture species in Africa, Europe or Asia and is substantially impacted by anthropogenic factors because of their low productivity and long maturation times. Almost year-round presence at breeding colonies makes understanding Cape Vulture breeding behaviour essential for their conservation. Camera traps, a first for this species, were used to investigate the effect of time of day and temperature on the presence and behaviours performed at nest sites. The number of vultures at a nest site was likely to be higher during the early morning and late afternoon when temperatures were lower, with significantly fewer individuals present at higher temperatures in the days before and after laying. Attendance of at least one adult at the nest was recorded for 86.9% and 99.8% of time points in the days before and after laying, respectively. Almost constant attendance during incubation may also be necessitated by predation pressure, with this study providing observation of possible predation pressure by White-necked Ravens (Corvus albicollis) at the colony. Here, we demonstrate that camera trapping is an effective method of studying Cape Vulture breeding behaviour, which improves understanding and allows more informed conservation measures to be implemented. Cape Vulture nest attendance is affected by temperature, so this species may be vulnerable to climatic changes and subsequent changes in predation pressure.
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Gone with the wind: The proximate and ultimate causes of the decline and extinction of the Bahama Nuthatch Sitta insularisNewly elevated to species rank, the Bahama Nuthatch Sitta insularis is or was a bark- and twig-gleaning insectivore only known in life from the pine forests of Grand Bahama in the Bahamas archipelago. It became increasingly difficult to find in the past 50 years, seemingly in part in response to multiple hurricanes in this century. In spring (June–April) 2018, when it was still known to be extant, we divided the island into seven sections and carried out point count transects with playback and measured habitat variables at 464 locations in pine forest across Grand Bahama. We made only six observations at six locations, all in the region of Lucayan North and each involving a single nuthatch (possibly all the same individual). Fourteen count points were within 500 m of the six locations, and tree size at these sites was greater in height and girth than at sites with no observations and indeed than at other sites within Lucayan North. Count points within 500 m of nuthatch records in 2004–2018 had larger trees and more snags than survey points over 500 m away from previous detections, while count points within 500 m of our 2018 nuthatch records tallied more snags than did those within 500 m of the 2004–2007 records. Declines in habitat quality, habitat extent, nesting substrate, and food availability (driven by logging, attritional island development, and the direct and indirect effects of hurricanes), plus speculated increases in populations of invasive predators/competitors and in major mortality events (hurricanes, increasing in force and frequency with climate change), are suspected to be the ultimate causes of the decline of the nuthatch, with Hurricanes Matthew and Dorian the proximate causes of its evident extinction in 2019.
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The Role of Antibody Expression and Their Association With Bladder Cancer Recurrence: A Single-Centre Prospective Clinical-Pilot Study in 35 PatientsBladder cancer (BC) is the 10th most common cancer in the UK, with about 10,000 new cases annually. About 75–85% of BC are non-muscle invasive (NMIBC), which is associated with high recurrence and progression rates (50–60% within 7–10 years). There are no routine biomarkers currently available for identifying BC patients at increased risk of developing recurrence. The focus of this research study was to evaluate antibody expression in BC patients and their association with cancer recurrence. Methods: 35 patients scheduled for TURBT were recruited after written informed consent. Ethical approval for the project was granted via IRAS (REC4: 14/WA/0033). Following surgical procedure, tissues were preserved in 10% buffered formalin and processed within 24 h in FFPE blocks. 7 sections (4 µm each) were cut from each block and stained for CD31, Human epidermal growth factor receptor-2 (HER-2), S100P, Cyclooxygenase-2 (COX-2), VEGFR-3 thrombomodulin and CEACAM-1 using immunohistochemistry. Clinical outcome measures (obtained via cystoscopy) were monitored for up to 6 months following surgical procedure. Results: There was significantly increased expression of CD31 (p < 0.001), HER-2 (p = 0.032), S100P (p < 0.001), COX-2 (p < 0.001), VEGFR-3 (p < 0.001) and decreased expression of thrombomodulin (p = 0.010) and CEACAM-1 (p < 0.001) in bladder tumours compared to normal bladder tissues. HER-2 expression was also significantly associated with cancer grade (p = 0.003), especially between grade 1 and grade 2 (p = 0.002) and between grade 1 and grade 3 (p = 0.004). There was also a significant association between cancer stage and HER-2 expression (p < 0.001). Although recurrence was significantly associated with cancer grade, there was no association with antibody expression. Conclusion: Findings from the present study may indicate an alternative approach in the monitoring and management of patients with BC. It is proposed that by allowing urological surgeons access to laboratory markers such as HER-2, Thrombomodulin and CD31 (biomarker profile), potentially, in the future, these biomarkers may be used in addition to, or in combination with, currently used scoring systems to predict cancer recurrence. However, verification and validation of these biomarkers are needed using larger cohorts.
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Spatio-Temporal Dynamics of Wolves in the Italian AlpsThe recolonization of wolves (Canis lupus) in Europe has become a notable ecological and conservation success in recent decades, though it presents various legislative and management challenges. These challenges are heightened by the wolves' wide-ranging distribution, which often crosses administrative boundaries. Effective management of wolves depends on robust data from well-designed monitoring programs, which are difficult to implement in fragmented regions. Italy has taken significant steps to address these issues, conducting the first national scale monitoring of wolf abundance and distribution in 2020-2021 using non-invasive genetic sampling (NGS) combined with Spatial Capture-Recapture (SCR) modelling. This thesis explores a variety of ways to implement and optimise the current monitoring strategies by focusing on the Italian Alpine region. This area, in particular, can rely on historical information on wolves since the first surveys in the 90’s and on a highly trained network of personnel dedicated to their monitoring that has been implemented over the years. The year of national monitoring has been a great success in coordination and results, but it opens the question of the feasibility of maintaining such high quality in the long term and with possible reductions in economic funds. In fact, with both European and national management of the species expected in the next future, constantly updated abundance estimates will be essential to ensure the conservation of the species. In this thesis I investigated how the combination of NGS and SCR to obtain population size estimates can be optimised by identifying reduction limits for the number of search transects and also for their repetitions within the sampling season. This will allow to reduce both effort and costs for the next years of population size monitoring while maintaining accuracy and precision. Additionally, I explored the feasibility of extending large-scale monitoring of wolf abundance in the Italian Alps using more cost-effective tools, such as camera traps. I demonstrated the unsuitability of a group of statistical models, Spatial Counts or unmarked SCR, which are often used when individuals in the population are not distinguishable from each other. After identifying the limitations of the current modelling framework, I proposed a solution to address some of these issues by incorporating the group-living nature of wolves into the existing model through an extension of the Spatial Counts approach. Finally, I tested whether the drivers of the latest phase of wolf expansion throughout the Italian Alpine region have changed over time. I used a Dynamic Occupancy model to analyse wolf presence-absence data from 2014 to 2021. This analysis revealed the increasing importance of prey richness in colonization and persistence dynamics together with the smoothed effect over time of human densities. Additionally, I identified key areas where new potential conflicts could arise in human-dominated landscapes. Addressing these challenges is crucial for the continued recovery and sustainable coexistence of wolves with human communities in Italy and all Europe. Finally, I discussed all the findings in light of future population management of wolves.
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Sweet mama: Affiliative interactions are related to the reproductive success of dominant female Alpine Marmots (Marmota marmota)Sociality is a complex phenomenon, able to influence multiple traits of an individual life history. In group-living mammals, sociality is likely to play a major role in the reproductive success of individuals. Here we investigate how sociality traits are associated to reproductive success in female Alpine marmots (Marmota marmota), a highly social and cooperative breeding ground squirrel distributed in the European Alps. We used social network analysis to calculate sociality metrics and hurdle generalized linear mixed models (hurdle GLMMs) to model the relationship between sociality metrics and reproductive success of individually tagged female Alpine marmots. Our results showed that centrality of a reproductive female within her social group and the number of social partners are positively related to reproductive success, while agonistic behavior was not related with reproduction. Our results highlight the importance of affiliative interactions with other group members in cooperative breeders, suggesting that in such systems female fitness could be more related to social cohesion than to costs of agonistic behaviors to maintain dominance status.
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The ARRIVE guidelines 2.0 author checklistThe ARRIVE guidelines 2.0 - full author checklist
