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Matthiopoulos, J.

Publications and source records attributed to Matthiopoulos, J..

10 recordsLinked to original sources

Applying integrated population models to guide conservation planning: Western Capercaillie in Scotland

O_LIMany conservation interventions prove ineffective because they lack a rigorous evidence-base. Multifactorial drivers and data limitations often hinder anticipatory planning and are difficult to tackle with standard methods. Predictive modelling approaches that integrate diverse data sources with biological hypotheses can bridge this gap by clarifying the drivers of decline and evaluating management options under uncertainty. C_LIO_LI We developed a Bayesian integrated population model (IPM) applicable to lekking species, combining incomplete data from different life stages and seasons while accounting for observation error. IPMs are widely recognised for reducing bias relative to single-data-stream analyses, yet their application in conservation planning remains limited. C_LIO_LIWe applied the model to the threatened Western Capercaillie population in Scotland, which has been declining since at least the 1980s despite decades of conservation efforts, a typical case requiring urgent, evidence-based management. By fitting the model to 30 years of biased and incomplete monitoring data, we investigated associations between demographic processes and their potential drivers, including weather variables, fence collision mortality and a proxy of predation pressure. We used model predictions to evaluate the joint effectiveness of proposed management actions aimed at improving vital rates, including fence management and diversionary feeding. C_LIO_LIData integration improved population estimate precision by 17-49% relative to standalone national survey estimates, confirming that the decline continued from 1990-2023. Reproductive rate was related to the pattern of April warming, negatively affected by pre-breeding precipitation and positively by vole abundance, the latter consistent with the alternative prey hypothesis. Model predictions indicated that combining diversionary feeding with fence removal produced the most favourable conservation outcomes, but growth remained limited and uncertainty included possible continued decline. C_LIO_LI5. This modelling approach forms a key component of Scotlands Capercaillie Emergency Plan 2025-2030, guiding management by assessing population-level responses and predicting conservation intervention outcomes. In future, the model could support formal adaptive management through iterative evaluation of interventions as new data become available. Beyond this case study, our integrated approach offers a transferable framework for managing multifactorial declines in other threatened species under uncertainty. C_LI

ecology↗

Diverse behavioural responses of vampire bats to human disturbance revealed by state-space modelling of sparse GPS data.

In Latin America, management of vampire bats has had inconsistent effects on the spread of lethal rabies infections from bats to humans and livestock. Positive and negative effects on rabies are hypothesised to reflect changes in bat roost fidelity and behaviour following human disturbance, but high landscape complexity has precluded monitoring bat movement in the areas where rabies transmission and bat management activity are most intense. We used animal-borne GPS tags to track 93 vampire bats in a rabies hotspot in the Peruvian Andes, where limited satellite visibility led to partial observation of animal locations. Immediately after capture, handling and tag application, 43% of bats, particularly males and bats with longer forearms, disappeared from the study area, suggesting a rapid roost switching response. Among the remaining 55 bats, a Bayesian state-space model revealed high individual heterogeneity on the disturbance night but on average increased flight distances. Over the remaining 8-night study period, bats gradually remained closer to the roost. These disturbance-driven shifts provide mechanisms to explain how bat disturbance can both accelerate and decelerate rabies spatial spread. More broadly, we present a modelling framework to infer key movement metrics in landscapes where GPS data limitations challenge conventional movement models.

ecology↗

In the face of competition, imperfect knowledge can lead to sustainable exploitation of a shared resource.

Overexploitation of a shared resource is a frequent phenomenon among groups of selfish consumers, known as the tragedy of the commons. To avoid "self-damage through self-interest", humans may either defend exclusive access to resources, or collectively adopt advanced cooperative behaviour and carefully designed spatial harvesting strategies to exploit a shared resource sustainably. However, why do many non-human species that are neither social nor territorial also appear to avoid overexploiting resources? This study shows that, even under highly competitive scenarios, cooperation is not necessary to sustainably exploit shared resources if individuals have imperfect knowledge about the distribution of those resources. Poorly informed individuals are more likely to inadvertently exploit resources in peripheral habitats, which may allow for higher resource renewal in the nearby and low-cost habitats, enhancing the sustainability of resource use. As a result, those consumers can achieve a long-term yield that approaches that of cooperative consumers and is higher than omniscient consumers. Ironically, while there might be an evolutionary drive for individuals to make well-informed decisions, consumers of shared resources may be collectively more prosperous when they make decisions based on less information. These findings might explain why apparently sub-optimal consumer behaviour appears so prevalent in nature.

ecology↗

Food webs can deliver win-win strategies for tropical agroforestry and biodiversity conservation

Balancing biodiversity conservation and agricultural productivity is commonly regarded as a trade-off, but such analyses overlook ecosystem services that functional biodiverse communities provide in agroecosystems, and the possibility that win-win strategies may exist. We developed a dynamic mechanistic community model of the bird-insect food web associated with African cocoa agroforestry, structurally informed by metabarcoding data on bird diets, and fitted to trapping data on species abundances. We used the model to predict equilibrium community composition under varying intensities of shade management and pesticide use. Our results indicate that low-intensity farming favours forest bird species, and potential pollinator abundance, with no increase in pest biomass. Furthermore, using simulations of pesticide application, we found that pesticides do not effectively reduce pest biomass, and result in forest bird extinction. Our mechanistic framework combines the influence of management and the direct and indirect effects of species interactions, and demonstrates that low intensity agriculture may provide a win-win for biodiversity and ecosystem services.

ecology↗

Strong breeding colony fidelity in northern gannets following High Pathogenicity Avian Influenza Virus (HPAIV) outbreak

High pathogenicity avian influenza virus (HPAIV) caused the worst seabird mass-mortalities on record in Europe across 2021-2022. The northern gannet (Morus bassanus) was one of the most affected species, with tens of thousands of casualties in the northeast Atlantic between April-September 2022. Disease outbreaks can drastically modify the movement ecology of animals and diminish spatial consistency, thereby increasing the potential for disease transmission. To detect potential changes in movement behaviour, we GPS-tracked breeding adults following the initial HPAIV outbreak, at three of the largest gannet breeding colonies where major mortality of adults and chicks occurred (Bass Rock, Scotland, UK; Grassholm, Wales, UK; Rouzic island, Brittany, France). Crucially, GPS-tracked birds remained faithful to their breeding sites and did not prospect other breeding colonies. They performed regular foraging trips at sea, similar to their behaviour before the outbreak. Gannet foraging effort was nonetheless lower than in 2019, thus surviving birds may have benefited from reduced intra- and interspecific food competition. Breeding colony fidelity of adult northern gannets following HPAIV mass-mortalities suggests limited long-term capacity to virus spread, which may contrast with the behaviour of adults during the disease outbreak, or with that of younger individuals.

ecology↗

Incorporating environmental heterogeneity and observation effort to predict host distribution and viral spillover from a bat reservoir.

Predicting the spatial occurrence of wildlife is a major challenge for ecology and management. In Latin America, knowledge of the true number and locations of vampire bat colonies precludes informed allocation of measures intended to limit lethal rabies spillover to humans and livestock. We inferred the complete spatial distribution of vampire bat roosts while accounting for observation effort and environmental covariates by fitting a Log Gaussian Cox Process model to the locations of 563 roosts in three regions of Peru. Our model explained 47% of the variance in the observed roost distribution and identified landscape correlates of roost establishment. Our model estimated that 1,795 roosts (76%) remain undiscovered and identified hotspots of undetected roosts in currently rabies-free areas, implying high risk for viral incursion. Incorporating the locations of undetected roosts improved spatial predictions of rabies spillover to livestock, revealed areas with disproportionate underreporting to surveillance systems, and indicated a higher rabies burden than previously estimated. We provide a robust approach to infer the distribution of a mostly unobserved bat reservoir that can inform strategies to prevent the re-emergence of an important zoonosis.

ecology↗

Fear and foraging in the ecosystem size spectrum generate diversity in fish life histories

Understanding how growth and reproduction will adapt to changing environmental conditions is a fundamental question in evolutionary ecology, but predicting the responses of specific taxa is challenging. Analyses of the physiological effects of climate change upon life history evolution rarely consider alternative hypothesized mechanisms, such as size-dependent foraging and the risk of predation, simultaneously shaping optimal growth patterns. To test for interactions between these mechanisms, we embedded a state-dependent energetic model in an ecosystem size-spectrum to ask whether prey availability (foraging) and risk of predation experienced by individual fish can explain observed diversity in life histories of fishes. We found that asymptotic growth emerged from size-based foraging and reproductive and mortality patterns in the context of ecosystem food web interactions. While more productive ecosystems led to larger body sizes, the effects of temperature on metabolic costs had only small effects on size. To validate our model, we ran it for abiotic scenarios corresponding to the ecological lifestyles of three tuna species, considering environments that included seasonal variation in temperature. We successfully predicted realistic patterns of growth, reproduction, and mortality of all three tuna species. We found that individuals grew larger when environmental conditions varied seasonally and spawning was restricted to part of the year (corresponding to their migration from temperate to tropical waters). Growing larger was advantageous because foraging and spawning opportunities were seasonally constrained. This mechanism could explain the evolution of gigantism in temperate tunas. Our approach addresses variation in food availability and individual risk as well as metabolic processes and offers a promising approach to understand fish life-history responses to changing ocean conditions.

ecology↗

Forest fragmentation drives zoonotic malaria prevalence in non-human primate hosts

Zoonotic disease dynamics in wildlife hosts are rarely quantified at macroecological scales due to the lack of systematic surveys. Non-human primates (NHPs) host Plasmodium knowlesi, a zoonotic malaria of public health concern and the main barrier to malaria elimination in Southeast Asia. Understanding of regional P. knowlesi infection dynamics in wildlife is limited. Here, we systematically assemble reports of NHP P. knowlesi and investigate geographic determinants of prevalence in reservoir species. Meta-analysis of 6322 NHPs from 148 sites reveals that prevalence is heterogeneous across Southeast Asia, with low overall prevalence and high estimates for Malaysian Borneo. We find that regions exhibiting higher prevalence in NHPs overlap with human infection hotspots. In wildlife and humans, parasite transmission is linked to land conversion and fragmentation. By assembling remote sensing data and fitting statistical models to prevalence at multiple spatial scales, we identify novel relationships between P. knowlesi in NHPs and forest fragmentation. This suggests that higher prevalence may be contingent on habitat complexity, which would begin to explain observed geographic variation in parasite burden. These findings address critical gaps in understanding regional P. knowlesi epidemiology and indicate that prevalence in simian reservoirs may be a key spatial driver of human spillover risk.

ecology↗

How animals endure by bending environmental space: Redefining the fundamental niche

For 70 years, the fundamental niche, the complete set of environments that allow an individual, population, or species to persist, has shaped ecological thinking. Yet, its properties have eluded quantification, particularly for mobile, cognitively complex organisms. Here, I derive a concise mathematical equation for the fundamental niche and fit it to population growth and distribution data. I find that, within traditionally defined environmental spaces, habitat heterogeneity and behavioural plasticity make the fundamental niche more complex and malleable, but also more predictable, than previously envisaged. This important re-evaluation restores the fundamental niche as a cornerstone of ecological theory and promotes it as a central tool for applied ecology. It quantifies how organisms buffer themselves from change by bending the boundaries of viable environmental space, and offers a framework for designing optimal habitat interventions to protect biodiversity or obstruct invasive species. ONE-SENTENCE SUMMARYThe fundemental niche of animal species

ecology↗

Local rabies transmission and regional spatial coupling in European foxes

Infectious diseases are often transmitted through local interactions. Yet, both surveillance and control measures are implemented within administrative units. Capturing local transmission processes and spatial coupling between regions from aggregate level data is therefore a technical challenge that can shed light on both theoretical questions and practical decisions.\n\nFox rabies has been eliminated from much of Europe through oral rabies vaccination (ORV) programmes. The European Union (EU) co-finances ORV to maintain rabies freedom in EU member and border states via a cordon sanitaire. Models to capture local transmission dynamics and spatial coupling have immediate application to the planning of these ORV campaigns and to other parts of the world considering oral vaccination.\n\nWe fitted a hierarchical Bayesian state-space model to data on three decades of fox rabies cases and ORV campaigns from Eastern Germany. Specifically, we find that (i) combining regional spatial coupling and heterogeneous local transmission allows us to capture regional rabies dynamics; (ii) incursions from other regions account for less than 1% of cases, but allow for re-emergence of disease; (iii) herd immunity achieved through bi-annual vaccination campaigns is short-lived due to population turnover. Together, these findings highlight the need for regular and sustained vaccination efforts and our modelling approach can be used to provide strategic guidance for ORV delivery. Moreover, we show that biological understanding can be gained from inference from partially observed data on wildlife disease.

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