Article

Predicting spatio-temporal recolonization of large carnivore populations and livestock depredation risk: Wolves in the Italian Alps

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Abstract

1. Wolves Canis lupus recently recolonized the Western Alps through dispersal from the Italian Apennines, representing one of several worldwide examples of large carnivores increasing in highly human-dominated landscapes. Understanding and predicting expansion of this population is important for conservation because of its direct impact on livestock and its high level of societal opposition. 2. We built a predictive, spatially explicit, individual-based model to examine wolf population expansion in this fragmented landscape, and livestock depredation risk. We developed the model based on known demographic processes, social structure, behaviour and habitat selection of wolves collected during a 10-year intensive field study of this wolf population. 3. During model validation, our model accurately described the recolonization process within the Italian Alps, correctly predicting wolf pack locations, pack numbers and wolf population size, between 1999 and 2008. 4. We then projected packs and dispersers over the entire Italian Alps for 2013, 2018 and 2023. We predicted 25 packs (95% CI: 19–32) in 2013, 36 (23–47) in 2018 and 49 (29–68) in 2023. The South-Western Alps were the main source for wolves repopulating the Alps from 1999 to 2008. The source area for further successful dispersers will probably shift to the North-Western Alps after 2008, but the large lakes in the Central Alps will probably act as a spatial barrier slowing the wolf expansion. 5. Using the pack presence forecasts, we estimated spatially explicit wolf depredation risk on livestock, allowing tailored local and regional management actions. 6. Synthesis and applications. Our predictive model is novel because we follow the spatio-temporal dynamics of packs, not just population size, which have substantially different requirements and impacts on wolf–human conflicts than wandering dispersers. Our approach enables prioritization of management efforts, including minimizing livestock depredations, identifying important corridors and barriers, and locating future source populations for successful wolf recolonization of the Alps.

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... Une fois ces relations établies, ils les « projettent géographiquement » sur toutes les Alpes, et concluent à une grande disponibilité et une continuité marquée d'habitats favorables au loup. Marucco & McIntire (2010) avaient également développé un modèle pour étudier l'expansion du loup dans les Alpes italiennes et le risque de prédation sur les troupeaux domestiques, cette fois sous une approche spatialement explicite. L'originalité de leur approche réside dans cette prise en compte explicite de l'habitat favorable et de la structure sociale comme un facteur crucial de la dynamique d'installation des meutes. ...
... En d'autres termes, le même modèle ajusté à des données de présence des loups en plaine ne sélectionnera évidemment pas les mêmes facteurs environnementaux et produira, après projection, une distribution prévisionnelle très différente. Marucco & McIntire (2010) discutent par ailleurs l'importance d'événements stochastiques, comme l'installation de meutes dans des endroits à faible probabilité donnée par le modèle, ce qui pourrait rendre la dynamique d'expansion très différente de celle prédite. ...
... Dans le cas du loup, le devenir de sa population en termes d'évolution numérique est très corrélé au bilan de mortalité totale. Quelles que soient les approches de modélisation utilisées (Marucco & McIntire 2010, les résultats obtenus convergent vers une mortalité maximale de 34% en moyenne au-delà de laquelle toute population de loups déclinera et, si elle est maintenue sur cette tendance, s'éteindra de manière certaine. Chapron et al. (2012) ont étudié les changements de seuils de viabilité en fonction du taux de mortalité, qui variait de 10% à 50%. ...
Technical Report
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UNE EXPERTISE COLLECTIVE SUR LES ASPECTS ÉCOLOGIQUES ET BIOLOGIQUES En avril 2016, le Ministère chargé de l'Environnement a demandé à l'ONCFS et au MNHN de lancer une démarche prospective d’évaluation écologique de la situation du loup en France à l’horizon 2025/2030 en se fondant sur une expertise collective scientifique indépendante. Le lancement officiel de cette expertise a eu lieu au MNHN le 7 juillet 2016 en présence de Mme Barbara Pompili. Le Ministère chargé de l'Environnement a demandé à l'ONCFS et au MNHN de coordonner des expertises collectives scientifiques indépendantes sur différents aspects de la présence du loup en France. The French Ministry of Environment has asked to ONCFS and MNHN to coordinate independent scientific expertise on different aspects of the wolf's presence in France.
... Une fois ces relations établies, ils les « projettent géographiquement » sur toutes les Alpes, et concluent à une grande disponibilité et une continuité marquée d'habitats favorables au loup. Marucco & McIntire (2010) avaient également développé un modèle pour étudier l'expansion du loup dans les Alpes italiennes et le risque de prédation sur les troupeaux domestiques, cette fois sous une approche spatialement explicite. L'originalité de leur approche réside dans cette prise en compte explicite de l'habitat favorable et de la structure sociale comme un facteur crucial de la dynamique d'installation des meutes. ...
... En d'autres termes, le même modèle ajusté à des données de présence des loups en plaine ne sélectionnera évidemment pas les mêmes facteurs environnementaux et produira, après projection, une distribution prévisionnelle très différente. Marucco & McIntire (2010) discutent par ailleurs l'importance d'événements stochastiques, comme l'installation de meutes dans des endroits à faible probabilité donnée par le modèle, ce qui pourrait rendre la dynamique d'expansion très différente de celle prédite. ...
... Dans le cas du loup, le devenir de sa population en termes d'évolution numérique est très corrélé au bilan de mortalité totale. Quelles que soient les approches de modélisation utilisées (Marucco & McIntire 2010, les résultats obtenus convergent vers une mortalité maximale de 34% en moyenne au-delà de laquelle toute population de loups déclinera et, si elle est maintenue sur cette tendance, s'éteindra de manière certaine. Chapron et al. (2012) ont étudié les changements de seuils de viabilité en fonction du taux de mortalité, qui variait de 10% à 50%. ...
... Stage-structured models including age-, breeding-or dispersing-specific individual categories have been developed to project population growth rate, and hence are relevant to make projections at the population level (Haight and Mech, 1997;Marescot et al., 2012). Individual-based models (IBMs) have also been used to model population dynamics and have proven to be more flexible to represent species with complex social structure like wolves or coyotes (Chapron et al., 2016;Marucco and McIntire, 2010;Pitt et al., 2003). IBMs are bottom-up models that simulate the fate of individuals interacting with each other and/or their environment. ...
... IBMs are bottom-up models that simulate the fate of individuals interacting with each other and/or their environment. IBMs can include many individual-level mechanisms (i.e., behavioral rules) and therefore can represent complex individual interactions as exhibited by these social species (Chapron et al., 2016;Haight et al., 2002;Marucco and McIntire, 2010;Pitt et al., 2003). Population-level results emerge from the individual-level simulations (Railsback and Grimm, 2012). ...
... Researchers have used IBMs to simulate the impact of wolf-removal strategies on depredation and population viability (Haight et al., 2002), to test the robustness of abundance indices (Chapron et al., 2016) or to project the recolonization of the species and the associated risk of depredation (Marucco and McIntire, 2010). The models were all based on the fundamental processes of mortality, reproduction and dispersal. ...
Article
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The occurrence of wolf populations in human-dominated landscapes is challenging worldwide because of conflicts with human activities. Modeling is an important tool to project wolf dynamics and expansion, and help in decision making concerning management and conservation. However, some individual behaviors and pack dynamics of the wolf life cycle are still unclear to ecologists. Here we present an individual-based model (IBM) to project wolf populations while exploring the lesser-known processes of the wolf life cycle. IBMs are bottom-up models that simulate the fate of individuals interacting with each other, with population-level properties emerging from the individual-level simulations. IBMs are particularly adapted to represent social species such as the wolf that exhibits complex individual interactions. Our IBM projects wolf demography including fine-scale individual behavior and pack dynamics based on up-to-date scientific literature. We explore four processes of the wolf life cycle whose consequences on population dynamics are still poorly understood: the pack dissolution following the loss of a breeder, the adoption of young dispersers by packs, the establishment of new packs through budding, and the different breeder replacement strategies. While running different versions of the IBM to explore these processes, we also illustrate the modularity and flexibility of our model, an asset to model wolf populations experiencing different ecological and demographic conditions. The different parameterization of pack dissolution, territory establishment by budding, and breeder replacement processes influence the projections of wolf populations. As such, these processes require further field investigation to be better understood. The adoption process has a lesser impact on model projections. Being coded in R to facilitate its understanding, we expect that our model will be used and further adapted by ecologists for their own specific applications.
... Wolf samples were collected yearly between 2001 to 2021 across the Italian Alps over the wolf-occupied range as part of the Piemonte Region monitoring Program [23,24]. Genetic analysis on biological samples, mainly scats, but occasional dead wolf carcasses, or saliva swabs from wounds associated with predation events have been regularly conducted. ...
... Direction. The directions of dispersal indicate that wolves in the Western Alps are moving in any direction, but primarily along the north-south axis for long distance movements, where the mountain chain is present, slightly towards less density areas present in the north compared to the south, where the recolonization process started [24]. However, we documented more wolves than expected that moved towards higher wolf density areas in the south, or to the east. ...
... It remains that the majority of studies indicate that dispersal direction is strongly influenced by the risk of interaction with humans [20], which is also showed in the present study by wolves avoiding the highly urbanized planes and dispersing towards territories in forested and mountainous areas with less human population density [16,47,48]. Mountains constitute the majority of the wolf-occupied area in the Western Alps [24], and likely constitute the habitat corridor facilitating similar dispersal routes among individuals, as seen for other species [49]. ...
Article
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Wildlife dispersal directly influences population expansion patterns, and may have indirect effects on the spread of wildlife diseases. Despite its importance to conservation, little is known about dispersal for several species. Dispersal processes in expanding wolf (Canis lupus) populations in Europe is not well documented. Documenting the natural dispersal pattern of the expanding wolf population in the Alps might help understanding the overall population dynamics and identifying diseases that might be connected with the process. We documented 55 natural dispersal events of the expanding Italian wolf alpine population over a 20-year period through the use of non-invasive genetic sampling. We examined a 16-locus microsatellite DNA dataset of 2857 wolf samples mainly collected in the Western Alps. From this, we identified 915 individuals, recaptured 387 (42.3%) of individuals, documenting 55 dispersal events. On average, the minimum straight dispersal distance was 65.8 km (±67.7 km), from 7.7 km to 517.2 km. We discussed the potential implications for maintaining genetic diversity of the population and for wildlife diseases spreading.
... Human density was found in previous studies to influence habitat choice and dispersal of wolves in Italy (Corsi et al. 1999;Marucco & Mcintire 2010). We therefore considered human density as a candidate covariate possibly explaining spatial variation in the diffusion parameter Di. ...
... We estimated the distribution of wolves using a model explicitly incorporating biological mechanisms and making best use of the information contained in species detections and nondetections. Besides, we explored the possibility of forecasting the potential future distribution of a large carnivore, which could be used to target management areas or focus on potential conflictual areas (Marucco & Mcintire 2010;Eriksson & Dalerum 2018). ...
Preprint
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Species distribution models (SDMs) are important statistical tools for ecologists to understand and predict species range. However, standard SDMs do not explicitly incorporate dynamic processes like dispersal. This limitation may lead to bias in inference about species distribution. Here, we adopt the theory of ecological diffusion that has recently been introduced in statistical ecology to incorporate spatio-temporal processes in ecological models. As a case study, we considered the wolf (Canis lupus) that has been recolonizing Eastern France naturally through dispersal from the Apennines since the early 90's. Using partial differential equations for modelling species diffusion and growth in a fragmented landscape, we develop a mechanistic-statistical spatio-temporal model accounting for ecological diffusion, logistic growth and imperfect species detection. We conduct a simulation study and show the ability of our model to i) estimate ecological parameters in various situations with contrasted species detection probability and number of surveyed sites and ii) forecast the distribution into the future. We found that the growth rate of the wolf population in France was explained by the proportion of forest cover, that diffusion was influenced by human density and that species detectability increased with increasing survey effort. Using the parameters estimated from the 2007-2015 period, we then forecasted wolf distribution in 2016 and found good agreement with the actual detections made that year. Our approach may be useful for managing species that interact with human activities to anticipate potential conflicts.
... We investigated wolf predation risk on livestock in Italy where, after a human-driven decline in the last two centuries, this large carnivore experienced a recovery following conservation efforts, recolonizing the entire Apennine chain and the Alps, thanks to the protection by laws, its adaptability to habitat changes and the marked recovery of wild prey populations (Boitani, 2000;Valiere et al., 2003;Fabbri et al., 2007;Galaverni et al., 2016). This positive trend also raised public negative attitudes due to the perceived high impact on human activities and caused concern of livestock breeders because of its predatory behaviour (Fritts et al., 2003;Marucco and McIntire, 2010;Dondina et al., 2015). ...
... Recent studies showed the usefulness of PRMs in supporting effective conservation and management actions at multiple stages of decisionmaking (i.e. from farm management to region-level policies; Miller, 2015). Thus, validation of PRMs is particularly relevant as they potentially represent a basis for management actions (Grimm and Railsback, 2005;Marucco and McIntire, 2010) and, given the high values of the validation statistics, we have confidence in our PRMs as decision support tools for implementing efforts to prevent livestock depredations. ...
Article
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Globally, large carnivore livestock predations are major causes of conflicts with humans, thus identifying hotspots of carnivore attacks is fundamental to reduce the impact of these, and hence promote coexistence with humans. Species distribution models combining predictor variables with locations of predation events instead of species occurrences (also known as predation risk models) are increasingly used to predict livestock depredation by carnivores, but they are often developed pooling attacks on different livestock species. We identified the main factors related to predation risk on livestock using an extensive dataset of 4604 locations of verified wolf predation events on livestock collected in northern and central Italy during 2008–2015 and assessed the importance of pooling versus splitting predation events by prey species. We found the best predictors of predation events varied by prey species. Specifically, predation risk increased with altitude especially for cattle, with grasslands especially for cattle and sheep and with distance to human settlements, especially for goats and livestock but only slightly for cattle and sheep. However, predation risk decreased as human population density, human settlements and artificial night-time light brightness increased, especially for cattle. Finally, livestock density was positively related to predation risk when herd exceeds 500 heads for km2. Moreover, prey-specific risk models are better tools to predict wolf predation risk on domestic ungulates. We believe that our approach can be applied worldwide on different predator-prey systems and landscapes to promote human-carnivore coexistence. Actually, while pooling predation events could be primarily used by managers and personnel of wildlife agencies/offices in developing general policies, splitting predation events by prey species could be used at farm-level to better identify livestock owners at risk in high-priority areas and which prevention tools and deterrents (e.g. electric fences, guarding dogs, predator-proof enclosures) should be applied, as the most effective measures differ by species.
... Finally, in addition to sampling eff ort, we considered the potential eff ect of road densities on the species detectability, fi rst through facilitation of site accessibility for the observers and second, because cross roads can be used as marking sites (Barja et al. 2004), which can lead to a higher detectability. Because presence signs rely partly on track records in the snow, we considered month as a categorical variable to account for the variation in detection conditions due to weather variations across the survey months (Marucco 2009). ...
... Determining favorable areas is often accomplished by building distribution maps using habitat suitability models (Mladenoff et al. 1999) or occupancy models (Marucco 2009). However, these studies often rely on a static relationship between the species of interest and its environment Our results showed that in 1994 the species was found only in the southern Alps, and then actively colonized towards the northern Alps at the beginning of the 2000s. ...
Thesis
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Les grands carnivores recolonisent l’Europe grâce à une augmentation des forêts et des populations d'ongulés sauvages ainsi que des mesures de conservation. Or, les carnivores entrent en interactions avec les activités humaines telles que l’élevage. Quantifier leur distribution peut aider à situer les impacts sur ces activités. Ces espèces sont très mobiles, difficiles à observer et vivent à de faibles densités. La modélisation de leur distribution présente plusieurs défis en raison 1) de leur détectabilité imparfaite, 2) de leur distribution dynamique dans le temps et 3) du suivi à grande échelle basé sur la collecte de données opportunistes sans mesure formelle de l'effort d'échantillonnage. Dans cette thèse, nous nous sommes concentrés sur deux espèces de grands carnivores, le loup et le lynx boréal, pour développer les méthodologies liées à la modélisation de la distribution d’espèces. Nous avons exploré l’application des modèles d’occupancy dans le contexte du suivi des grands carnivores en Europe. Ces modèles établissent le lien entre la présence d’une espèce et l’environnement dans le but d’établir la proportion d'une zone d'étude que l’espèce occupe, tout en prenant en compte une détectabilité imparfaite.Plus précisément, nous avons d'abord évalué la dynamique de la distribution des loups en France de 1994 à 2016, tout en prenant en compte leur détection imparfaite. Nous avons montré l'importance de prendre en compte l’effort d'échantillonnage variant dans le temps et dans l'espace à l’aide de de modèles d’occupancy dynamique.Deuxièmement, comme des faux positifs peuvent être présents lors de la surveillance d'espèces rares, nous avons développé un modèle dynamique d’occupancy qui tenait compte simultanément des faux négatifs et des faux positifs pour analyser conjointement des données qui contenaient à la fois des détections certaines et des détections incertaines. L'analyse des données sur le lynx boréal dans les pays alpins a suggéré que l'incorporation de détections incertaines produisait des estimations des paramètres écologiques plus précises.Troisièmement, nous avons développé un modèle qui prenait en compte l'hétérogénéité de la détection tout en traitant les faux positifs. En appliquant notre nouvelle approche au loup en France, nous avons démontré que l'hétérogénéité de la détection du loup était principalement due à un effort d'échantillonnage hétérogène dans l'espace.Quatrièmement, pour traiter des sources de données multiples, nous avons développé un modèle de processus ponctuel de Poisson qui permettait l'inclusion de différentes sources de données lors de la construction des SDMs. Nous avons montré comment la combinaison des données sur la distribution permettait d’optimiser un suivi en répondant à la question de savoir quelle(s) source(s) d'information apporterait l’essentiel de l’information lors du suivi du lynx en Norvège.Cinquièmement, pour comprendre les mécanismes sous-jacents de la colonisation des loups en France, nous avons développé un cadre statistique pour estimer l'occupation spatio-temporelle et la dynamique des effectifs en utilisant le cadre de diffusion écologique. Nous avons montré le potentiel de notre approche pour prédire la distribution future potentielle du loup à court terme, un élément qui pourrait contribuer à cibler des zones de gestion ou se concentrer sur des zones de conflit potentiel.Dans l'ensemble, nos travaux montrent que les données opportunistes peuvent être analysées à l'aide de modèles de distribution d’espèces qui prennent en compte les contraintes liées au type de suivi utilisé pour produire les données. Nos approches peuvent être utilisées par les gestionnaires pour optimiser la surveillance des grands carnivores, cibler des zones de présence potentielles et contribuer à proposer des mesures destinées à atténuer les conflits.
... This recent expansion led to the emergence of conflicts with humans (Ripple et al. 2014). In this context, accurate distribution mapping, i.e., species distribution models (SDMs; Elith & Leathwick 2009), is essential to determine the conservation status and recovery success (IUCN, 2012), to target potential areas of occurrence and understand large carnivores range dynamics, identify the possible areas where they might be recovering in the future (Chapron et al., 2014) and mitigate conflicts often associated with the recovery of large carnivores (Guillera-Arroita et al. 2015) like, e.g., livestock depredation related to wolves' recolonization (Marucco & Mcintire, 2010). However, their rarity, elusive behavior and low density render efficient monitoring of large carnivores difficult (Ripple et al. 2014). ...
... Assessing the distribution of large carnivores at large scales is a central information for assessing their conservation status, and abundance (IUCN, 2012;Jedrzejewski et al., 2018), target potential conflict areas (Marucco & Mcintire, 2010) and understand the mechanism of the distribution's dynamics for successful management (Eriksson & Dalerum, 2018). Producing more precise and less biased estimates by adding ambiguous data with a model accounting for false positive detections can bring new insights into species' distribution in places where getting unambiguous data is challenging. ...
Article
Full-text available
As large carnivores recover throughout Europe, there is a need to study their distribution to determine their conservation status and assess the potential for conflicts with human activities. However, efficient monitoring of many large carnivore species is challenging due to their rarity, elusive behavior and large home range size. In Europe, most current monitoring protocols rely on multiple detection methods, which can include opportunistic sightings from citizens in addition to designed surveys. Two types of detection errors may occur in such monitoring schemes; false negatives and false positives. When not accounted for, both can bias estimates from species distribution models (SDMs). False negative detections can be accounted for in SDMs that deal with imperfect detection. In contrast, false positive detections, due to species misidentification, have only rarely been accounted for in SDMs. Generally, researchers use ad hoc methods to avoid false positives through data filtering to discard ambiguous observations prior to analysis. These practices may discard valuable ecological information on the distribution of a species. Here, we investigated the costs and benefits of including data types that might include false positives rather than discard them for SDMs of large carnivores. We showcase a dynamic occupancy model that simultaneously accounts for false negatives and positives to jointly analyze data that include both unambiguous detections and ambiguous detections. Using simulations, we show that the addition of ambiguous detections increases the precision of parameter estimates. The analysis of data on the Eurasian lynx (Lynx lynx) suggested that incorporating ambiguous detections produced more precise estimates of the ecological parameters and revealed additional occupied sites in areas where the species is likely expanding. Overall, our work shows that ambiguous data should be considered when studying the distribution of large carnivores, through the use of dynamic occupancy models accounting for misidentification.
... For instance, during the 1970s, the Apennine wolf (Canis lupus italicus) experienced its historical minimum population size, fragmented in two areas in the Southern Apennines [167,178]. Since the late 1980s, thanks to increased efforts to protect large carnivores undertaken on most continents, including Italy [179][180][181][182][183], the wolf is gradually recolonising some territories of the Apennines [184][185][186][187]. In particular, in the Cilento, Vallo di Diano e Alburni National Park (Southern Italy), the widest protected area in Italy, the wolf population, estimated at four individuals in 1975 [178], is naturally expanding at a fast pace with a population currently estimated at many dozens of specimens [53]. ...
Article
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The recent and ever-growing problem of boar (Sus scrofa forms including wild boar, hybrid and feral pig) expansion is a very complex issue in wildlife management. The damages caused to biodiversity and the economies are addressed in different ways by the various countries, but research is needed to shed light on the causal factors of this emergency before defining a useful collaborative management policy. In this review, we screened more than 280 references published between 1975-2022, identifying and dealing with five hot factors (climate change, human induced habitat modifications, predator regulation on the prey, hybridization with domestic forms, and transfaunation) that could account for the boar expansion and its niche invasion. We also discuss some issues arising from this boar emergency, such as epizootic and zoonotic diseases or the depression of biodiversity. Finally, we provide new insights for the research and the development of management policies.
... What is supposed to happen when a predator returns to an area where prey species have been living free from terrestrial predators for a long time? The natural wolf expansion into the Alps (Fabbri et al., 2007;Marucco & McIntire, 2010;Scandura, Apollonio, & Mattioli, 2001) provided an opportunity for ecologists to accept the challenge proposed by Creel and Christianson (2008) to design field studies that determine the relative magnitude of risk effects and direct predation in wild populations that are not manipulated. In the present paper, we assessed the indirect effects of the natural expansion of the grey wolf on the antipredator behaviour of Alpine ibex (Capra ibex), taking into account that wolf predation has limited consequences on ibex population dynamics (Palmegiani, Gazzola, & Apollonio, 2013). ...
Article
Predators may influence their prey populations not only through direct lethal effects, but also by causing behavioural changes. The natural expansion of the wolf (Canis lupus) into the Alps provided the rare opportunity to monitor the responses of a prey species to the return of a large predator. Density effects have rarely been considered in the study of antipredator strategies. We examined the effects of wolf recolonisation and density modifications on group size and use of safe areas by Alpine ibex (Capra ibex) in Gran Paradiso National Park (Italy), where no large terrestrial predator has been present for about a century. We documented that, in a few years, the variation in the factors affecting the landscape of fear caused significant modifications in ibex behavioural patterns that could not be accounted for by density changes only. Male groups decreased in size and moved closer to safer areas. The distance of female groups from refuge sites, instead, was not affected, and their propensity to live in groups was scarcely modified. Behavioural modifications likely caused a reduction in nutrient intake in adult male ibex, as they necessarily used lower‐quality feeding patches. Our results showed that male and female ibex, which are characterised by a strong dimorphism, adopted different strategies to solve the conflicting demands of foraging efficiently and avoiding predators.
... One fundamental improvement is to directly associate compensation systems with preventive measures enforced Boitani 2012, Ravenelle andNyhus 2017). Moreover, compensation systems should also prioritize in assisting farmers to apply those measures correctly (Álvares et al. 2014), especially in areas where carnivores have been absent for a period of time (Marucco and McIntire 2010). ...
Technical Report
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Livestock depredation is one of the main wolf-human conflict issues both in Europe and worldwide. The aim of the project is to study and evaluate wolf-livestock conflicts in Tzoumerka NP and to compare our findings with other protected areas in Greece. We have in particular set the following six research objectives: 1. To assess and describe traditional free-ranging livestock raisers’ profile in Tzoumerka NP. 2. To record wolf depredation levels on cattle, sheep and goat herds as the main baseline metric of wolf-human conflicts in Tzoumerka NP. 3. To identify and evaluate the principal damage prevention methods adopted by local livestock farmers in Tzoumerka NP. 4. To assess levels of livestock guarding dog mortality due to the illegal use of poisoned baits as a major conservation problem in the area in Tzoumerka NP. 5. To evaluate satisfaction levels of livestock farmers regarding the national compensation system in Tzoumerka NP. 6. To compare the main results stemming from Tzoumerka NP with other similar studies previously completed in other protected areas and draw relevant conclusions. © 2019 University of Ioannina and WWF Greece
... Factors influencing decisions of dispersers are more complex in well-established populations where there is no open space between territories (also described as saturated). Establishment of new pairs may be hindered by factors such as large pack size, inability to find a mate, higher mortality due to encounters with territorial packs, inability to hold a territory in encounters with larger packs, or available openings due to death of a breeder in an existing pack (Marucco and McIntire, 2010). Space rather than food appeared to be the limiting factor for wolves in Yellowstone, although lower survival at high densities was also influenced by the distribution of prey on the landscape (Cubaynes et al., 2014). ...
Chapter
Behavioral flexibility of wolves is linked with many characteristics associated with intelligence, such as subtle communication , problem-solving, and learning in the social context of a family group. To better understand cooperative breeding in wolves, researchers focus on individual behavior within groups (ontogeny, parental and alloparental care, communication, reproductive hormones and behavior, behavioral inhibition of reproduction). However, individual decisions are influenced by the neighborhoods surrounding family groups (genetic structure, dispersal, conflict between groups). Furthermore, dynamic ecosystems influence the shifting costs and benefits of individual decisions (foraging behavior, hunting tactics, anthropogenic effects). Emerging questions examine genetic and epigenetic influences on canid behavior. DOI: 10.1016/B978-0-12-809633-8.90078-5
... Overall, results agree with previous studies suggesting that predation risk mainly results from habitat factors favouring the co-occurrence of large predators and livestock (e.g. Marucco and McIntire, 2010;Dondina et al., 2015), though a more complex picture emerged in our study when analysing predation intensity rather than occurrence. ...
Article
Predation on livestock is a source of human-wildlife conflicts and can undermine the conservation of large car-nivores. To design effective mitigation strategies, it is important to understand the determinants of predation across livestock species, which often differ in husbandry practices, vulnerability to predators and economic value. Moreover, attention should be given to both predation occurrence and intensity, because these can have different spatial patterns and predictors. We used spatial risk modelling to quantify factors affecting wolf predation on five livestock species in Portugal. Within the 1619 parishes encompassing the entire wolf range in the country, the national wolf compensation scheme recorded 17,670 predation events in 2009-2015, each involving one or more livestock species: sheep (31.7%), cattle (27.7%), goats (26.8%), horses (14.8%) and donkeys (3.2%). Models built with 2009-2013 data and validated with 2014-2015 data, showed a shared general pattern of predation probability on each species increasing with its own density and proximity to wolf packs. For some species there were positive relations with the density of other livestock species, and with habitat variables such as altitude, and land cover by shrubland and natural pastures. There was also a general pattern for predation intensity on each species increasing with its own density, while proximity to wolf packs had no significant effects. Predation intensity on goats, cattle and horses increased with the use of communal versus private pastures. Our results suggest that although predation may occur wherever wolves coexist with livestock species, high predation intensity is mainly restricted to particular areas where husbandry practices increase the vulnerability of animals, and this is where mitigation efforts should concentrate.
... Minimizing wolf-livestock conflicts requires identifying conditions that place livestock at risk and focusing outreach and interventions at a local scale (Treves et al. 2011). Risk mapping, commonly used to predict spatial locations where hazards will occur (Treves et al. 2011), has been increasingly implemented in human-carnivore conflict mitigation (Kissling et al. 2009, Marucco and McIntire 2010, Soh et al. 2014. In the Great Lakes region, predictive maps were developed to identify areas at risk to livestock depredation by wolves in Wisconsin and Minnesota (Treves et al. 2004(Treves et al. , 2011 and later used to predict risk for the Upper Peninsula of Michigan (using models derived in Treves et al. 2004 andEdge et al. 2011). ...
Article
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Minimizing wolf-livestock conflicts requires identifying conditions placing livestock at risk and focusing adaptive management at a local scale. Gray wolves Canis lupus began recolonizing Washington in 2008. We used generalized linear mixed models to investigate characteristics of wolf pack territories in Idaho and Montana from 1991–2008 (n  137) and predict cattle Bos taurus depredation risk for current and probable wolf-occupied areas in Washington. Cattle depredation risk increased with cattle abundance and if the pack depredated cattle the previous year. When models were applied to wolf pack territories in Washington from 2008–2016 (n  43), 3 of 7 (43%) depredating pack territory/years were predicted at ≥61% depredation risk. During the summer grazing season (1 May – 31 October) when most cattle depredations (97%; n  34) occurred in Washington, cattle east of the Cascade Mountains were often on grazing allotments whereas cattle west of the Cascade Mountains were located on small, private farms. Thus, relative cattle abundance per grazing allotment and county likely represented cattle depredation risk east and west of the Cascade Mountains, respectively. County-wide and allotment cattle abundance forecasted 10.3% and 1.4% of probable wolf-occupied areas at ≥ 61% cattle depredation risk, respectively. These risk models and maps provide locations for federal and state wildlife managers to focus depredation prevention measures and a template for future analyses as wolves continue to recolonize Washington.
... Factors influencing decisions of dispersers are more complex in well-established populations where there is no open space between territories (also described as saturated). Establishment of new pairs may be hindered by factors such as large pack size, inability to find a mate, higher mortality due to encounters with territorial packs, inability to hold a territory in encounters with larger packs, or available openings due to death of a breeder in an existing pack (Marucco and McIntire, 2010). Space rather than food appeared to be the limiting factor for wolves in Yellowstone, although lower survival at high densities was also influenced by the distribution of prey on the landscape (Cubaynes et al., 2014). ...
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Similar to other large-bodied social carnivores, wolves hunt in groups as well as in singles and pairs. However, communicative and reproductive behaviors of grey wolves differ in distinctive ways from cat-like (Feliformia) and other dog-like (Caniformia) species in the taxonomic order Carnivora. For over a half century, researchers have been fascinated with teasing apart which fixed aspects of wolf behavior are relatively more instinctive (associated with heritable genotypes), and which flexible aspects are relatively more variable due to individual experiential learning and behavioral plasticity. Recent advances in technology have led to some unexpected answers and generated new questions about wolf behavior, at both the genomic and ecological levels of behavioral systems. (preprint of entry to be included in the 2018 revisions of the Encyclopedia of Animal Behavior)
... First, our depredation risk model was developed at a 1 km resolution landscape scale based on GIS layers. Therefore, the model does not consider other factors at the individual or population level that can contribute to depredation risk, such as breed, sex, age, or management of livestock (De Azevedo and Murray, 2007;Ogada et al., 2003;Teichman et al., 2013) or demographics of wolves (Marucco and McIntire, 2010). Second, our risk map assumes Mexican wolves are present throughout the entire study area. ...
Article
Aim Predation on livestock is one of the primary concerns for Mexican wolf (Canis lupus baileyi) recovery because it causes economic losses and negative attitudes toward wolves. Our objectives were to develop a spatial risk model of cattle depredation by Mexican wolves in the USA portion of their recovery area to help reduce the potential for future depredations. Location Arizona and New Mexico, USA. Methods We used a presence-only maximum entropy modeling approach (Maxent) to develop a risk model based on confirmed depredation incidents on public lands. In addition to landscape and human variables, we developed a model for annual livestock density using linear regression analysis of Animal Unit Month (AUM), and models for abundance of elk (Cervus canadensis), mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginiana) using Maxent, to include them as biotic variables in the risk model. We followed current recommendations for controlling model complexity and other sources of bias. Results The primary factors associated with increased risk of depredation by Mexican wolf were higher canopy cover variation and higher relative abundance of elk. Additional factors with increased risk but smaller effect were gentle and open terrain, and greater distances from roads and developed areas. Main conclusions The risk map revealed areas with relatively high potential for cattle depredations that can inform future expansion of Mexican wolf distribution (e.g., by avoiding hotspots) and prioritize areas for depredation risk mitigation including the implementation of active non-lethal methods in depredation hotspots. We suggest that livestock be better protected in or moved from potential hotspots, especially during periods when they are vulnerable to depredation (e.g. calving season). Our approach to create natural prey and livestock abundance variables can facilitate the process of spatial risk modeling when limitations in availability of abundance data are a challenge, especially in large-scale studies.
... Consequently, during the construction of a HSM for wolves it is essential to distinguish between predictors of areas with just a general presence of the species, including floaters, and the permanent range of the species, where they can establish territories (Marucco & McIntire, 2010). Models based on observations of solitary wolves wandering in search of mates and free territories, especially if such data included, for example, media reports, may provide inconclusive results (Fechter & Storch, 2014). ...
Article
Aim To compare predictions of the habitat suitability model (HSM) for wolves Canis lupus in Poland with actual wolf distribution in western Poland after 15 years of recolonization. Location Western Poland (WPL, ca. 136,000 km2), west of the 18°48′E meridian. Methods Data on wolf occurrence (8,057 records) were gathered in 2001–2016. Wolf presence in 10 × 10 km cells was classified as follows: (1) permanent occurrence with reproduction, (2) permanent occurrence with no reproduction and (3) sporadic occurrence (interpreted as dispersing individuals). These cells were compared to all 10 × 10 km cells in WPL with respect to the probability of wolf occurrence as predicted by the HSM and habitat variables important for wolves. For temporal analysis, data were divided into two 8-year subsets: the initial and later phases of wolf recovery. Results Wolves were recorded in 259 cells (19.8% of the study area). The pairs and packs settled in areas predicted by the HSM to have good and very good habitat, in cells characterized by high forest cover and low densities of roads. Wolf groups that reproduced were found in the best-quality habitats characterized by denser forest cover and markedly lower shares of anthropogenic structures. Dispersing individuals were mostly recorded in unsuitable and suboptimal habitats, and they avoided both the poorest and the best habitats. In the initial phase of wolf recovery, cells selected by wolves for settling down and those used by dispersing wolves did not differ in their habitat parameters. However, in the later phase, as WPL became more saturated with wolf packs, dispersing individuals were recorded in less suitable habitats. Main conclusions The HSM for Polish wolves predicted with high accuracy the areas later occupied by wolf groups in the western part of the country. A similar approach may also be useful to predict the future distribution of wolves in the lowlands of central and western Europe where environmental conditions are comparable and recolonizing wolves originate from the same source population.
... In accordance with our best BPOD model, grazing areas easily reachable by wild canids are more vulnerable, considering that in almost all cases, the fencing system adopted in the study area is inadequate to protect livestock. The structure of wild canid packs within the study area could be an important variable to forecast predation risk (Marucco and McIntire, 2010). It can be supposed that stable family groups could have different impacts on livestock depredation compared to wandering dispersers or loners, but we didn't have data to account for this variable. ...
Article
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The recovery of large carnivores in human dominated landscapes can cause controversy and concern for livestock producers, especially where wild predator populations and farmland overlap. This is the case in the Grosseto province, located in the southern part of Tuscany, Italy. Anticipating where predator attacks are likely to occur can help focus mitigation efforts. We suggest a three-step method to predict wild canid depredation risk using presence only data on wild canid detections and confirmed depredation events in the study area. We obtained the probability of occurrence for canids and depredation events based on ecological variables and then performed an ensemble model following an ad-hoc procedure. We compared models’ outputs obtained from two different approaches to species distribution modeling: Maximum Entropy (Maxent) and Bayesian for Presence-only Data (BPOD) testing their ability to predict the occurrence of events. The ecological niche factor analysis (ENFA) was used to assess the importance of each environmental variable in the description of the presence points. Forested areas were identified as the most important attribute predicting wild canid occurrence. Livestock predation was most likely to occur close to farms where sheep densities were higher and more accessible. Higher depredation risk zones were characterized by proximity to forested areas and the presence of landscape features that allowed wild canids to reach pastures with minimum effort such as the network of smaller watercourses. Only 15% of the total sheep farms fall within higher risk areas, indicating that depredation was facilitated by environmental conditions (e.g. closeness to the woods) rather than the availability of prey. Overall BPOD performed better than Maxent in terms of sensitivity, suggesting that BPOD could be a promising approach to predict probability of occurrence using presence only data.
... Consequently, ABMs have equipped scientific disciplines, such as ecology, epidemiology, and social sciences, with a powerful tool for answering complex questions in an understandable way. ABMs have, for example, increased our understanding of basic biological processes (review: Deangelis & Grimm, 2014) including forest dynamics (review: Bugmann, 2001); spatial dynamics of terrestrial mammals (e.g., Marucco & Mcintire, 2010); bird breeding synchrony (e.g., Jovani & Grimm, 2008); and the spread of diseases in host populations (e.g., Eisinger & Thulke, 2008). Of particular relevance to this study is the ability for ABMs to realistically model the evolution of life history strategies in environments where both density-and density-independent processes affect individuals with different states (e.g., Mysterud & Bischof, 2010). ...
Article
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If we want to understand how climate change affects long-lived organisms, we must know how individuals allocate resources between current reproduction and survival. This trade-off is affected by expected environmental conditions, but the extent to which density independent (DI) and density dependent (DD) processes interact in shaping individual life histories is less clear. Female reindeer (or caribou: Rangifer tarandus) are a monotocous large herbivore with a circumpolar distribution. Individuals that experience unpredictable and potentially harsh winters typically adopt risk averse strategies where they allocate more resources to building own body reserves during summer and less to reproduction. Such a strategy implies that the females do not reproduce or that they produce fewer or smaller offspring. A risk averse strategy thus results in females with large autumn body reserves, which is known to increase their survival probabilities if the coming winter is harsh. In contrast, females experiencing predictable winters may adopt a more risk prone strategy in which they allocate more resources to reproduction as they do not need as many resources to buffer potentially adverse winter conditions. This study uses a seasonal state-dependent model showing that DD and DI processes interact to affect the evolution of reproductive strategies and population dynamics for reindeer. The model was run across a wide range of different winter climatic scenarios: One set of simulations where the average and variability of the environment was manipulated and one set where the frequency of good and poor winters increased. Both reproductive allocation and population dynamics of reindeer were affected by a combination of DI and DD processes even though they were confounded (harsh climates resulted in lowered density). Individual strategies responded, in line with a risk sensitive reproductive allocation, to climatic conditions and in a similar fashion across the two climatic manipulations.
... Today, Switzerland is characterised by vast areas of favourable wolf habitats, which include areas with low human density, intermediate elevations, high prey richness, and the presence of natural land covers (Glenz et al. 2001;Marucco & McIntire 2010;Falcucci et al. 2013). Under similar favourable natural conditions, the formation of stable and reproducing packs is typically observed 2-7 years after first recolonisation by single long-distance dispersers (Poulle, Lequette & Dahier 1999;Wagner et al. 2012;Fabbri et al. 2014) with subsequent population expansion. ...
Article
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Habitat suitability models (HSMs) are commonly used in conservation practise to assess the potential of an area to be occupied and colonised. A major limitation of these models, however, is the omission of spatially explicit understanding of human acceptance towards the focal species. As wildlife is more and more subject to human-dominated landscapes, ignoring the sociological component will result in misrepresentation of the observed processes and inappropriate management. We distributed 10 000 questionnaires across Switzerland and identified key socio-demographical factors correlated with human acceptance of the wolf. We then created a spatially explicit acceptance model based on geo-referenced socio-demographical, social and geographical information. Finally, we combined our acceptance model with a HSM to obtain a unified socio-ecological suitability model, which included human and ecological components. We showed that the key factors associated with human acceptance were perception of how harmful the wolf is, interest in wolf-related issues, need for livestock protection, and fear of the wolf. Perceived harmfulness was in turn correlated with direct and indirect experience with the wolf, and level of education. Our acceptance map predicted decreasing acceptance with increasing altitude of residency and proximity to locations of confirmed wolf presence. This resulted in the overall opposition to the wolf for the Alpine region, albeit substantial regional differences. We found little spatial overlap (6% of Switzerland) between areas where the wolf was accepted and areas of suitable habitat. These areas of socio-ecological suitability were concentrated in the Jura Mountains and in the eastern and southern Alps, and were absent in the western and central Alps. Particularly in the Jura region, which is yet to be colonised, management of human acceptance will be a crucial conservation target. Synthesis and applications. We developed an integrative, socio-ecological approach that allowed us to accurately reproduce recent wolf recolonisation. We anticipate our framework to be a powerful tool to reliably evaluate overall suitable habitats and predict short to medium-term range expansion for species whose distribution is also dependent on human attitudes. Because our approach is sensitive to both the ecological and human component, it is ideally suited to identify key regions where proactive and targeted socio-ecological management plans are needed.
... In this context, predation on cattle is of particular concern, given its high socio-economic value (Iliopoulos et al., 2009). Furthermore, there is widespread extensive cattle rearing, virtually without vigilance and protection measures, in areas were the wolf has been absent for a long time and is recently recolonizing, such as pastureland in the European Alps and dehesas in western Spain (Blanco and Cortés, 2009;Marucco and McIntire, 2010;Kaczensky et al., 2013). Clearly, finding solutions to mitigate wolf predation on cattle would be useful to facilitate the sharing of landscapes by wolves and humans, particularly in regions holding important wolf populations within human dominated landscapes . ...
... At the end of the Second World War, Italian wolves were close to extinction, surviving at their historical minimum population size in two isolated areas in the Southern Apennines (Zimen and Boitani, 1975;Boitani, 1984Boitani, , 1992. However, since the late eighties socioecological changes and the increase in wild ungulates in natural areas have favored a spontaneous re-expansion of Italian wolves along the Apennines to the Western Italian and French Alps (Breitenmoser, 1998;Boitani, 2000;Vali ere et al., 2003;Fabbri et al., 2007;Marucco and McIntire, 2010). On one hand, the impact of this rapid recovery can increase conflicts with hunters seeking the same prey, livestock breeders suffering economic losses caused by wolf predation on domestic herds , and the general public many of whom have a historical fear of wolves, which are still perceived as a potential threat to human safety (Linnell and Boitani, 2011;Glikman et al., 2012). ...
Article
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After centuries of massive decline, the recovery of the wolf (Canis lupus italicus) in Italy is a typical conservation success story. To learn more about the possible role of parasites in the wolves' individual and population health and conservation we used non-invasive molecular approaches on fecal samples to identify individual wolves, pack membership, and the taeniids present, some of which are zoonotic. A total of 130 specimens belonging to 54 wolves from eight packs were collected and examined. Taeniid eggs were isolated using a sieving/flotation technique, and the species level was identified by PCR (gene target: 12S rRNA and nad1). Taeniid prevalence was 40.7% for Taenia hydatigena, 22.2% for T. krabbei, 1.8% for T. polyachanta and 5.5% for Echinococcus granulosus. The prevalence of E. granulosus is discussed. Our results show that the taeniid fauna found in wolves from the Foreste Casentinesi National Park is comparable to that described for other domestic and wild Italian canids and provides insights into the wolves’ diet and their relationship with the environment.
... In this context, predation on cattle is of particular concern, given its high socio-economic value (Iliopoulos et al., 2009). Furthermore, there is widespread extensive cattle rearing, virtually without vigilance and protection measures, in areas were the wolf has been absent for a long time and is recently recolonizing, such as pastureland in the European Alps and dehesas in western Spain (Blanco and Cortés, 2009;Marucco and McIntire, 2010;Kaczensky, 2013). Clearly, finding solutions to mitigate wolf predation on cattle would be useful to facilitate the sharing of landscapes by wolves and humans, particularly in regions holding important wolf populations within human dominated landscapes (Linnell & Boitani, 2012). ...
Article
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Mitigating conflicts associated with predation on livestock is essential for conserving large carnivores in human dominated landscapes. This is generally addressed by targeting at individual management practices affecting predation risk, often disregarding that different livestock husbandry systems (i.e., groups of farms sharing similar resource bases, production patterns and management practices) with different vulnerabilities to predation may coexist within predator ranges, each of which requiring tailored prescriptions to reduce predation. Here we evaluated the importance of considering both husbandry systems and individual management practices to mitigate conflicts due to cattle predation by wolves in Portugal, where attacks on cattle increased >3 times in 1999-2013. Government records from 2012-2013 indicated that only <2% of cattle farms suffered wolf attacks, of which <4% had >10 attacks.year-1. We found that attacks were concentrated in the free-ranging husbandry system, which was characterised by multi-owner herds, largely grazing communal land far from shelter, and seldom confined. Protecting these herds at night in winter was the most important factor reducing wolf attacks, which could be achieved by changing practices of about 25% of farmers in this system. Attacks were much lower in the semi-confined system, probably because herds grazed pastures closer to shelter, and they were often confined with fences or in barns. Farms bringing calves <3 months old to pastures were associated with about 90% of attacks, but changing this practice would involve about 50% of farmers in this system. Our results underline the importance of identifying livestock husbandry systems, and to adjust mitigation strategies to each system.
... These issues have resulted in humans continuing as the primary threat to wolves: one study tracking dispersing wolves in Spain identified illegal hunting and automobile strikes as the cause of >90% of wolf deaths (Blanco & Cortés, 2007). Predicting the dynamics of recolonization can help address these issues, allowing management agencies to prepare communities to deal with potential conflict (Marucco & McIntire, 2010). ...
Article
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Austria is one of the few countries in Europe that has not been recolonized by stable populations of wolves, yet many dispersing individuals have been observed. Understanding spatial and temporal patterns of recolonization can help prepare management agencies for conflict that may arise and allow for adaptive management, yet characterizations of the recolonization process are lacking in most areas where it is occurring. Here, a geospatial application of an agent-based model was explored as a potential tool in characterizing spatial and temporal patterns of wolf recolonization in Austria. Sub-models for wolf appearance in Austria, dispersal through a habitat-suitability model, mating, pack formation and death were developed in the Agent Analyst programming environment and parameterized with literature-derived values. Model outputs included total wolf numbers, wolf presence locations, and the number and location of packs formed. Throughout model runs, wolf presence locations were predictably focused near known neighbouring populations; yet different parameterizations resulted in varied larger-scale movement patterns. About half of all runs resulted in pack formation, predominantly near the Slovenian and Italian borders, indicating that it is possible for the model to predict recolonization. Although the approach has high uncertainty, it can lend insight into recolonization and can be refined through the collection of more empirical data and the application of further research into wolf decision-making.
... Wolf conservation has always been a very controversial topic because of the impact of wolf predatory activity on livestock [1]. If on one hand, wolves held in zoos may help raise public awareness on the need to preserve the species, on the other they may have their welfare compromised by the impossibility to perform natural behaviours, including predation itself [2,3]. ...
Article
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This study investigated the effects of two feeding enrichment programs on the behaviour of a captive pack of European wolves (Canis lupus lupus) and their correlation with both zoo visitors’ interest towards the exhibit and their overall perception of the species. Behavioural data (exploration, stereotypies, social interactions, activity/inactivity rates) were collected on four male wolves during four two-week long phases: initial control, hidden food, novel object, final control. Three observation sessions were performed daily: before, during and after feeding. Number of visitors and their permanence in front of the exhibit were recorded. After watching the wolves, visitors were asked to fill out a brief questionnaire in order to investigate their perception of captive wolf welfare, as well as their attitude towards wolf conservation issues. Despite the high inter-individual variability in their behavioural response, all wolves seemed to benefit from feeding enrichment. With regard to visitors, interest in the exhibit increased when enrichment was provided. Visitors’ perception of the level of welfare of wolves improved if they attended a feeding session, especially during the novel object phase. Visitors’ attitude towards wolf conservation issues also improved during feeding sessions, regardless of enrichment provision.
... We suggest that the notion of problem carnivores in agropastoral landscapes in Africa requires additional investigation. We argue, for instance, that it is also possible that other fine-scale landscape and habitat variables may exist that would explain the spatial pattern of spotted hyena raids in bomas better than the variable tested in the current study (Porten et al., 2014), which thus invokes the possibility of considering further research on carnivore raids in bomas at a finer scale than the one we have completed (Marucco & McIntire, 2010;Montgomery et al., 2018;Treves, Martin, Wydeven, & Wieden-hoeft, 2011). ...
Article
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Human-carnivore conflicts and retaliatory killings contribute to carnivore popula-tions' declines around the world. Strategies to mitigate conflicts have been developed, but their efficacy is rarely assessed in a randomized case-control design. Further, the economic costs prevent the adoption and wide use of conflict mitigation strategies by pastoralists in rural Africa. We examined carnivore (African lion [Panthera leo], leopard [Panthera pardus], spotted hyena [Crocuta crocuta], jackal [Canis mesomelas], and cheetah [Acinonyx jubatus]) raids on fortified (n = 45, total 631 monthly visits) and unfortified (traditional, n = 45, total 521 monthly visits) livestock enclosures ("bomas") in northern Tanzania. The study aimed to (a) assess the extent of retaliatory killings of major carnivore species due to livestock depredation, (b) describe the spatiotem-poral characteristics of carnivore raids on livestock enclosures, (c) analyze whether spatial covariates influenced livestock depredation risk in livestock enclosures, and (d) examine the cost-effectiveness of livestock enclosure fortification. Results suggest that (a) majority of boma raids by carnivores were caused by spotted hyenas (nearly 90% of all raids), but retaliatory killings mainly targeted lions, (b) carnivore raid attempts were rare at individual households (0.081 raid attempts/month in fortified enclosures and 0.102 raid attempts/month in unfortified enclosures), and (c) spotted hyena raid attempts increased in the wet season compared with the dry season, and owners of fortified bomas reported less hyena raid attempts than owners of unforti-fied bomas. Landscape and habitat variables tested, did not strongly drive the spatial patterns of spotted hyena raids in livestock bomas. Carnivore raids varied randomly both spatially (village to village) and temporally (year to year). The cost-benefit analysis suggest that investing in boma fortification yielded positive net present values after two to three years. Thus, enclosure fortification is a cost-effective strategy to promote coexistence of carnivores and humans.
... Conflicts are dynamic -the landscape of risk can change over time (Olson et al., 2014) and that change can be instantaneous (e.g., decision to let a pet dog run loose in the core of a wolf pack territory). Thus, more meaningful evaluations of risk can be developed by 1) restricting analysis to areas of known co-occurrence (e.g., Olson et al., 2014), 2) incorporating spatial and non-spatial variables (e.g., Pimenta et al., 2018), 3) incorporating spatiotemporal data into risk models to account for dynamic patterns of human activities and predator populations in risk analysis (e.g., Marucco and McIntire, 2010;Olson et al., 2014), or 4) examining the landscape of risk as a surface of multiple, competing risks (this work). ...
Article
Managing risks requires an adequate understanding of risk-factors that influence the likelihood of a particular event occurring in time and space. Risk maps can be valuable tools for natural resource managers, allowing them to better understand spatial characteristics of risk. Risk maps can also support risk-avoidance efforts by identifying which areas are relatively riskier than others. However, risks, such as human-carnivore conflict, can be diverse, multi-faceted, and overlapping in space. Yet, efforts to describe risk typically focus on only one aspect of risk. We examined wolf complaints investigated in Wisconsin, USA for the period of 1999 to 2011. We described the spatial patterns of four types of wolf-human conflict: livestock depredation, depredation on hunting hounds, depredation on non-hound dogs, and human health and safety concerns (HHSC). Using predictive landscape models and discriminant functions analysis, we visualized the landscape of risk as a continuous surface of overlapping risks. Each type of conflict had its own unique landscape signature; however, the probability of any type of conflict increased closer to the center of wolf pack territories and with increased forest cover. Hunting hound depredations tended to occur in areas considered to be highly suitable wolf habitat, while livestock depredations occurred more regularly in marginal wolf habitat. HHSC and non-hound dog depredations were less predictable spatially but tended to occur in areas with low housing density adjacent to large wildland areas. Similar to other research evaluating the risk of human-carnivore conflict, our data suggests that human-carnivore conflict is most likely to occur where humans or human property and large carnivores co-occur. However, identifying areas of co-occurrence is only marginally valuable from a conservation standpoint and could be described using spatially-explicit human and carnivore data without complex analytical approaches. These results challenge our traditional understanding of risk and the standard approach used in describing risk. We suggest that a more comprehensive understanding of the risk of human-carnivore conflict can be achieved by examining the spatial and non-spatial factors influencing risk within areas of co-occurrence and by describing the landscape of risk as a continuous surface of multiple overlapping risks.
... oystercatchers Haematopus ostralegus, UK [54], skylarks Alauda arvensis in Denmark [55] and river salmonids in California, USA [56], sometimes across thousands of kilometres squared, e.g. grey wolves Canis lupus in the Italian alps [57], African elephants Loxodonta africana in the Kenya-Tanzania border [58] and tigers Panthera tigris in Nepal's Chitwan National Park [59]. ...
Article
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Harmonious coexistence between humans, other animals and ecosystem services they support is a complex issue, typically impacted by landscape change, which affects animal distribution and abundance. In the last 30 years, afforestation on grasslands across Great Britain has been increasing, motivated by socio-economic reasons and climate change mitigation. Beyond expected benefits, an obvious question is what are the consequences for wider biodiversity of this scale of landscape change. Here, we explore the impact of such change on the expanding population of common buzzards Buteo buteo , a raptor with a history of human-induced setbacks. Using Resource-Area-Dependence Analysis (RADA), with which we estimated individuals' resource needs using 10-day radio-tracking sessions and the 1990s Land Cover Map of GB, and agent-based modelling, we predict that buzzards in our study area in lowland UK had fully recovered (to 2.2 ind km ⁻² ) by 1995. We also anticipate that the conversion of 30%, 60% and 90% of economically viable meadow into woodland would reduce buzzard abundance nonlinearly by 15%, 38% and 74%, respectively. The same approach used here could allow for cost-effective anticipation of other animals' population patterns in changing landscapes, thus helping to harmonize economy, landscape change and biodiversity.
... We investigated resource selection of wolf reproductive sites at Johnson (1980) 3rd order of selection using Conditional Matched Case Control 1:1 Logistic Regression (Duchesne et al., 2010). We compared RS used by each wolf pack to random sites available within each pack territory with a 3000 m buffer (mean areas of 278.3 ± 107.6 km2), considering average territory sizes in the Alps (Marucco & McIntire, 2010). We applied a first level neighborhood (3x3) to RS used respect to sampling unit (grid cell of 100 m) considering that pups movements in early summer are usually<500 m from RS (Packard, 2003). ...
Article
Ecological knowledge is considered an important factor in environmental policy-making. However, the opportunity for ecologists to influence policy can often occur within discrete time policy windows, and seizing these opportunities has been heavily emphasized as a recent global conservation need. In 2017 the Natura 2000 Conservation Measures have been finalized in Italy, and delineated the management policy and institutional responsibilities of Natura 2000 Sites, after obligations of the EU Habitat Directive. In this timeframe, we developed a multi-scalar hierarchical habitat selection model for wolf reproductive-sites to identify potentially favorable habitat for wolf reproduction in the western Italian Alps, based on 19 years of data. This habitat suitability model was useful for the definition of species conservation requirements within the Natura 2000 Sites, and has been adopted in legislation processes, representing a successful example of ecological modelling fitting into a relevant policy window and informing legal instruments to achieve nature conservation goals.
... Therefore, it is theoretically possible to design and parameterize spatially explicit models to identify and predict conflict hotspots where carnivores kill livestock. Such risk maps could be instrumental for spatial prioritization of interventions to reduce livestock depredation by large carnivores and human retaliation on large carnivores (Stahl et al. 2002;Treves et al. 2004Treves et al. , 2011Marucco and McIntire 2010). ...
Book
How can humans and wildlife coexist? In the new book "Tarangire: Human-Wildlife Coexistence in a Fragmented Ecosystem", published @SpringerNature, we synthesize interdisciplinary research, highlight challenges & propose solutions that work for humans and wildlife.
... Therefore, it is theoretically possible to design and parameterize spatially explicit models to identify and predict conflict hotspots where carnivores kill livestock. Such risk maps could be instrumental for spatial prioritization of interventions to reduce livestock depredation by large carnivores and human retaliation on large carnivores (Stahl et al. 2002;Treves et al. 2004Treves et al. , 2011Marucco and McIntire 2010). ...
Chapter
We synthesize data on the ecology of large carnivores in the Tarangire Ecosystem (TE). Despite anthropogenic pressures, all large carnivore species (lions Panthera leo, spotted hyena Crocuta crocuta, striped hyena Hyena hyena, leopard Panthera pardus, cheetah Acinonyx jubatus, and wild dog Lycaon pictus) have persisted in this fragmented ecosystem consisting of multiple protected areas among a matrix of village lands. The focal species were widely distributed across land-use gradients. While the comparatively abundant spotted hyena permanently occupied village lands, other species only sporadically used these human-dominated areas. Across species, carnivores used village lands more frequently during the rainy season, possibly following seasonal shifts in the movement of prey species. These processes can increase human-carnivore interactions, expanding the potential for conflict. In some areas, leopards, lions, and striped hyenas reached high densities, whereas cheetahs and wild dogs occurred patchily and at low densities. Our review suggests that the existence of diverse protected areas contribute to the persistence of the large carnivore community. The persistence of lions, cheetahs, and wild dogs appears dependent on human-induced mortality and prey depletion. Conserving large carnivores in TE requires the application of interventions that reduce human-induced mortality while simultaneously conserving the spatio-temporal distributions of prey species.
... Therefore, it is theoretically possible to design and parameterize spatially explicit models to identify and predict conflict hotspots where carnivores kill livestock. Such risk maps could be instrumental for spatial prioritization of interventions to reduce livestock depredation by large carnivores and human retaliation on large carnivores (Stahl et al. 2002;Treves et al. 2004Treves et al. , 2011Marucco and McIntire 2010). ...
Chapter
Facilitating coexistence between humans and large carnivores is one of the most complex and pressing conservation issues globally. Large carnivores pose threats to human security and private property, and people may respond to those risks with retaliation which can jeopardize the persistence of carnivore populations. The nature of these interactions can be influenced by several variables including ecological, anthropogenic as well as political dimensions. The Tarangire Ecosystem (TE) of northern Tanzania is a stronghold for multiple large carnivore species. Despite multi-faceted and long-term carnivore conservation efforts being implemented in the ecosystem, the anthropogenic impacts on carnivore populations are pervasive. As only a portion of the TE is fully protected, the wide-ranging nature of carnivores brings them into close contact with people living among a matrix of village lands. Consequently, this ecosystem experiences high levels of human-carnivore conflicts. In this chapter, we synthesize the existing information to characterize the extent, impacts, and spatiotemporal patterns of human-carnivore interactions (which often result in severe conflicts, causing harm to people, livestock, and carnivores), examine the efficacy and challenges of implementing interventions designed to reduce human-carnivore conflict, and explore the socio-economic dimensions of these mitigation efforts.
... Therefore, it is theoretically possible to design and parameterize spatially explicit models to identify and predict conflict hotspots where carnivores kill livestock. Such risk maps could be instrumental for spatial prioritization of interventions to reduce livestock depredation by large carnivores and human retaliation on large carnivores (Stahl et al. 2002;Treves et al. 2004Treves et al. , 2011Marucco and McIntire 2010). ...
Chapter
In the Tarangire Ecosystem, elephants frequently use pastoral areas, where they interact with people and livestock. To characterize the elephant-livestock interface in Manyara Ranch, we used a social-ecological approach to capture the herders’ and the elephants’ perspectives of these interactions. We interviewed cattle herders to assess their perceptions of elephants relative to other wildlife species (n = 117 interviews) and observed how elephants responded to sound playbacks associated with humans and cattle relative to sounds of wildlife species (n = 300 playbacks). Most herders (86%) supported elephant conservation, and reported spatial avoidance of elephants as the main strategy to avoid negative interactions. Among eleven large mammal wildlife species, herders ranked elephants as the fifth most problematic species to cattle. Elephants frequently reacted (e.g., bunching, fleeing, shaking the head and moving the trunk, or approaching) to human-related sound playbacks (79% of playbacks), and reacted less frequently when exposed to sounds of cattle (62%) or wildlife (34%). Playback experiments suggested that while elephants primarily reacted non-aggressively when faced with livestock, aggressive elephant behavior may be triggered by human behavior. Evidence from both the interview data and the behavioral experiments suggest that coexistence between elephants and pastoralists is mostly facilitated by mutual spatial avoidance.
... Twelve publications studied Italian and Tanzanian cases(Figure 2.4). In Italy, six studies concerned wolf depredation on livestock(Ciucci et al., 2018;Dondina et al., 2015;Marucco & McIntire, 2010; Milanesi et al., 2019Milanesi et al., , 2015Zingaro and Boitani, 2017), while the other six were on wild pig (Sus scrofa) depredation on crop(Amici et al., 2012;Cappa et al., 2019;Cerri et al., 2017;Ficetola et al., 2014;Greco et al., 2021;Lombardini et al., 2016). In Tanzania, the emblematic case of elephant (Loxodonta africana) depredation on crops was investigated in three publications(Denninger Snyder et al., 2021;Kiffner et al., 2021;Scheijen et al., 2019), while big cat depredation on livestock was investigated in four publications ...
Thesis
Les espèces qui se nourrissent de plantes ou d’animaux élevés ou capturés par l’homme, un comportement appelé « déprédation », entraînent souvent de graves Conflits Homme-Faune sauvage (CHF). La déprédation a été signalée dans le monde entier et, dans les écosystèmes marins, elle a été développée par de nombreux grands prédateurs se nourrissant des prises de pêche, ce qui a un impact à la fois sur les activités de pêche et les interactions écologiques. Cependant, bien que les approches écosystémiques soient de plus en plus utilisées dans la gestion des pêches, les effets de la déprédation sur l’ensemble de l’écosystème sont encore rarement considérés de manière holistique. Par conséquent, cette thèse a (i) identifié les limites, manques et priorités pour le développement d’approches de modélisation intégrant la déprédation et (ii) évalué la capacité de deux approches de modélisation existantes pour caractériser les conséquences de la déprédation marine et, plus spécifiquement, comprendre les enjeux et conditions requises pour que les activités d’exploitation halieutique et les déprédateurs marins puissent co-exister. Cette thèse est composée de cinq chapitres. Le chapitre 1 présente le contexte dans lequel s’inscrit ces travaux. Le chapitre 2 identifie les principales lacunes dans les connaissances et met en évidence les principales orientations futures pour parvenir à une inclusion efficace de la déprédation dans les études de modélisation en réalisant une revue systématique. Le chapitre 3 utilise le cadre Ecopath pour évaluer les effets de la déprédation sur l'écosystème dans une étude de cas bien documentée impliquant des mammifères marins et une pêcherie commerciale. Le chapitre 4 s'appuie sur une modélisation qualitative pour évaluer les conditions de persistance d'une ressource exploitée, d'une pêcherie et d'une espèce déprédatrice dans les systèmes marins touchés par la déprédation, et la façon dont la déprédation marine affecte les réponses à long terme à des scénarios alternatifs. Enfin, la discussion générale présentée dans le chapitre 5, fournit des recommandations qui vise à mieux comprendre et prévoir les effets de la déprédation au niveau du socio-écosystème.
... Nevertheless, there is paucity of studies integrating the available information to show where it converges and to provide a better understanding of the mechanisms behind the dispersal process. The applicability of a more integrated understanding ranges from projecting the dynamics of wolf populations under different natural and human conditions, including shifts in distribution ranges and connectivity between subpopulations, to locating areas with high livestock depredation risk (Marucco & McIntire, 2010). ...
Article
Full-text available
Dispersal is a key demographic process involving three stages: emigration, transience and settlement; each of which is influenced by individual, social and environmental determinants. An integrated understanding of species dispersal is essential for demographic modelling and conservation planning. Here, we review the dispersal patterns and determinants documented in the scientific literature for the grey wolf (Canis lupus) across its distribution range. We showed a surprisingly high variability within and among study areas on all dispersal parameters – dispersal rate, direction, distance, duration and success. We found that such large variability is due to multiple individual, social and environmental determinants, but also due to previously overlooked methodological research issues. We revealed a potential non-linear relationship between dispersal rate and population density, with dispersal rate higher at both ends of the gradient of population density. We found that human-caused mortality reduces distance, duration and success of dispersal events. Furthermore, dispersers avoid interaction with humans, and highly exposed areas like agricultural lands hamper population connectivity in many cases. We identified numerous methodological research problems that make it difficult to obtain robust estimates of dispersal parameters and robust inferences on dispersal patterns and their determinants. In particular, analyses where confounding factors were not accounted for led to substantial knowledge gaps on all aspects of dispersal in an otherwise much-studied species. Our understanding of wolf biology and management would significantly benefit if wolf dispersal studies reported the results and possible factors affecting wolf dispersal more transparently.
... The high mortality rate during roads crossing indirectly affect the success of dispersion (F. Marucco & McIntire, 2010) even though at the local level these dynamics are not representing an important threat to wolf expansion, as confirmed by the constant increase and expansion of wolf packs reported in the latest provincial report on large carnivores for 2020. In Trentino-Alto Adige (hereafter TAA), possible threats of this kind for wolf conservation may be represented by the ecological barrier of the Val d'Adige, where two busy motorways and Brennero railway run in parallel with the Adige River. ...
Thesis
The Eastern Alps, and in particular Trentino-Alto Adige and Veneto regions, have undergone a rapid recolonization by wolves. In less than a decade the area saw an increase in the number of packs, from one pack in 2013 to 20-25 packs in 2019. Such comeback has implied relevant consequences especially on livestock breeders’ activities, which have experienced an increase in predations by wolves. The combination of this fast recolonization process, the unreadiness of the local people and management authorities to this new and impacting presence, and the general lack of knowledge on this species has led to a significant intensification of the attention given to the wolf by the local media. In addition, the well-known political impact of the species has further contributed to exacerbating social conflicts and polarizing the debate regarding wolves. As previous studies have demonstrated, public opinion on a given issue is highly influenced by how the media decide to frame and present it, and media framing of a given issue is in turn highly influenced by the main political forces acting at the local scale. Based on these assumption, it has been conducted a content analysis of printed and online newspaper articles published between 2019 and 2020 in these two Italian regions. Specifically, it has been assessed how the wolf is framed by the local media and what the main themes and topics presented are. In particular, were analyzed the main news elements, which are the ones that have the highest impact on the reader, that is the title, subtitle and images. Successively, it has been given a score to each element based on the attitude towards wolves, with three possible scores: positive, neutral and negative. Further detailed information from each news, such as the main topic of the news and other mentioned topics, have been collected within a database. Moreover, it has been assessed the presence and prevalence of beliefs, judgements and misconceptions about wolves. The information extracted allowed to make comparisons about the type of media framing between the two regions (Veneto and Trentino-Alto Adige) and also between the Provinces of Trento and Bolzano, as well as between Italian and German language newspapers in Alto Adige. This study provides a further comparison based on media framing among different newspapers. Results eventually offered an overview of the current media framing situation on the wolf in the area, and highlighted possible opportunities to improve connections and information sharing between wolf experts and journalists to promote a more objective and correct information on the Large Carnivore.
... (Marucco et al., 2009;Marucco and McIntire, 2010 in which hybridization has not been detected yet(Fabbri et al., 2007). The details about model parametrization are shown in Appendix B.We modeled hybridization at the level of the formation of the reproductive pairs. ...
Thesis
Full-text available
Hybridization is the interbreeding of individuals from distinct populations. Anthropogenic hybridization is a significant threat that can cause species’ extinction. It is therefore fundamental to assess this threat and evaluate the effectiveness of management actions in an adaptive management loop. We developed demographic estimation and projection models to answer to these questions and showed their application.In the first chapter we: 1) developed a model to estimate prevalence in free‐ranging populations 2) carried out a simulation study to i) evaluate model performance, ii) compare it to naive quantifications of prevalence and iii) assess the accuracy of model-based estimates of prevalence under different sampling scenarios. The main results from this chapter were that i) the prevalence of hybrids could be estimated ii) model‐based prevalence consistently had better performance than naive prevalence in the presence of differential detectability and assignment probability and was unbiased for sampling scenarios with high detectability. Our results underline the importance of a model‐based approach to obtain unbiased estimates of prevalence of different population segments.In the second chapter we adopted targeted non-invasive genetic sampling and the capture-recapture estimation model developed in Chapter 1 to estimate the prevalence of wolf-dog hybrids in a local, protected wolf population in the northern Apennines, Italy. We discuss the results in the light of previous assessment of prevalence of wolf x dog admixed individuals in Western Europe and we illustrate the implications of the results for wolf conservation and for the management of wolf x dog hybridization in human-dominated landscapes. In particular, we estimated 64-78% recent hybrids occurring in 6 out of the 7 surveyed packs. Our findings underline that in human-modified landscapes wolf-dog hybridization may raise to unexpected levels if left unmanaged, and that reproductive barriers or dilution of dog genes through backcrossing should not be expected, per se, to prevent occurrence and the spread of introgression.In the third chapter we present a new matrix population model to project population dynamics of animal populations in presence of hybridization. We apply the model to two real-world case studies of terrestrial (wolf x dog) and marine mammal species (common dolphin Delphinus delphis x striped dolphin Stenella coeruleoalba). Our projections highlighted that i) hybridization leads to genomic extinction in the absence of reproductive isolation, ii) rare or depleted species are particularly vulnerable to genomic extinction, iii) genomic extinction depends mainly on demographic parameters of parental species, iiii) maintaining healthy and abundant populations prevents genomic extinction.In the fourth chapter we built an individual based model describing the life cycle of the gray wolf by contemplating social dynamics traits linked to hybridization rates. We applied this model to investigate the hybridization dynamics of wolves in a study population the Northern Apennines, Italy, in order to evaluate the effectiveness of different management scenarios aimed to reduce the abundance of admixed individuals during a ten-generation time. We showed that in presence of continuative immigration of admixed individuals any management action proved ineffective. In presence of immigration by pure wolves all management actions produced a decrease in prevalence, although their relative effectiveness changed depending on the mating choice scenario. In all the simulated scenarios, the impact of hybridization is predicted to extend at broad scales as large numbers of admixed dispersers are produced. Moreover, we identified demographic and social processes that need to be further investigated to more accurately project the outcomes of management alternatives.
... The number of packs in Lithuania, which is estimated to be 100, suggests a likelihood of territorial overlap, similar to that observed in Poland (Jędrzejewski et al. 2007). Such a situation may affect efforts to control wolf livestock depredation (Marucco and McIntire 2010). Lithuania has a unique opportunity for evaluating the consequences of increasing wolf-bag limits (nearly doubled in the hunting season 2018-2019) with establishment of a national program for continuous registration of wolf observations. ...
Article
Context. In many countries, annual wolf surveys based on snow-track counts have become unreliable because of inconsistent snow coverage. We considered incidental observations by volunteers throughout the year as an alternative monitoring protocol. Aims. We recruited interested citizens throughout Lithuania, including hunters, foresters and farmers, to estimate wolf distribution, abundance, pack numbers and group size from 2015 to 2018. Methods. Observation-based records of wolves were collected using simple questionnaires that included time, location and method of observation (e.g. track, scat, vocalisation or prey-kill remains). We summarised 979 reports of 1938 observed wolves. Key results. Volunteer reports suggested an increase in wolf distribution and abundance from 2015 to 2018. The observed number of wolf packs was estimated to be at least 100 by 2018, pack size increased to 3.6, and the share of single wolves decreased from 56% in 2015 to 40% in 2018. Conclusions. We found that volunteer observations can provide useful information on wolf distribution, pack size and pack numbers. Our results support previous reports of expanding wolf populations in the Baltic region. Implications. Results of our citizen-science effort by Nature Research Centre and Lithuanian Hunters and Fishers Association have been accepted by the Ministry of Environment as a complement to other surveys in Lithuania and should aid in developing an informed wolf-management policy.
... The number of packs in Lithuania, which is estimated to be 100, suggests a likelihood of territorial overlap, similar to that observed in Poland (Jędrzejewski et al. 2007). Such a situation may affect efforts to control wolf livestock depredation (Marucco and McIntire 2010). Lithuania has a unique opportunity for evaluating the consequences of increasing wolf-bag limits (nearly doubled in the hunting season 2018-2019) with establishment of a national program for continuous registration of wolf observations. ...
Article
Context. In many countries, annual wolf surveys based on snow-track counts have become unreliable because of inconsistent snow coverage. We considered incidental observations by volunteers throughout the year as an alternative monitoring protocol. Aims. We recruited interested citizens throughout Lithuania, including hunters, foresters and farmers, to estimate wolf distribution, abundance, pack numbers and group size from 2015 to 2018. Methods. Observation-based records of wolves were collected using simple questionnaires that included time, location and method of observation (e.g. track, scat, vocalisation or prey-kill remains). We summarised 979 reports of 1938 observed wolves. Key results. Volunteer reports suggested an increase in wolf distribution and abundance from 2015 to 2018. The observed number of wolf packs was estimated to be at least 100 by 2018, pack size increased to 3.6, and the share of single wolves decreased from 56% in 2015 to 40% in 2018. Conclusions. We found that volunteer observations can provide useful information on wolf distribution, pack size and pack numbers. Our results support previous reports of expanding wolf populations in the Baltic region. Implications. Results of our citizen-science effort by Nature Research Centre and Lithuanian Hunters and Fishers Association have been accepted by the Ministry of Environment as a complement to other surveys in Lithuania and should aid in developing an informed wolf-management policy.
... The model makes the following assumptions (Marescot et al., 2012): 1) if subordinates survive (with survival rate Ss) one year in the natal pack they will then leave and become individuals in dispersal by their third year of age; 2) the subordinates never directly transition to being breeders; 3) individuals in dispersal can either die or survive (with survival rate Sd), and gain access to reproduction by establishing a new pack (with transition rate to the breeder stage Pes) or remain dispersers (1-Pes); 4) breeders never lose their status remaining in the breeder stage and surviving with survival rate Sa. To run the projections we used the demographic parameters that were estimated for the expanding wolf population in the Italian Alps (Marucco et al., 2009;Marucco and McIntire, 2010 in which hybridization has not been detected yet (Fabbri et al., 2007). The details about model parametrization are shown in Appendix B. ...
Article
Hybridization affects the evolution and conservation status of species and populations. Because the dynamics of hybridization is driven by reproduction and survival of parental and admixed individuals, demographic modelling is a valuable tool to assess the effects of hybridization on population viability, e.g., under different management scenarios. While matrix models have been used to assess the long-term consequences of hybridization between crops and wild plants, to our knowledge they have not been developed for animal species. Here, we present a new matrix population model to project population dynamics in a system with two parental species or populations that interbreed. We consider the dynamics of males and females of the two parental groups as separate components, each described by species-specific vectors of initial abundance and projection matrices. Then we model hybridization as the production of hybrid fertile offspring due to the interaction of reproductive individuals of different parental species. Finally, we apply the model to two real-world case studies regarding a terrestrial and a marine mammal species in the presence of hybridization. Specifically, we investigate 1) the genomic extinction probability of two interbreeding dolphin species within a semi-enclosed gulf in Greece, under different hybrids’ fitness scenarios, 2) the possible outcomes of wolf x dog hybridization events for an expanding wolf population in Italy, under different reproductive isolation scenarios, 3) the sensitivity of the probability of genomic extinction to the main demographic parameters in the two case studies.
... These decrees and protection laws, joined with the human abandonment of high-altitude territories after the second World War (Cerea and Marcantoni 2016;Fondazione Montagne Italia 2017), contributed to the wolf's natural recolonization starting from the Apennines in central Italy and moving toward the south-western part of the Alps (Liguria and Piedmont regions at the border with France). Currently the wolf alpine population is moving to the eastern part of the Alps (year of first documented presence: 2003 in Lombardy, 2010 in Trentino-Alto Adige, and 2012 in Veneto) (Marucco et al. 2018), where they are coming in contact with the wolf population coming from the Dinaric mountains and the Carpathians (Ciucci et al. 2009;Marucco and Mcintire 2010). Wolves reappeared in South Tyrol (hereinafter ST) in 2010 after more than 100 years of absence (Stauder et al. 2019; Autonomous Province of Bolzano 2020). ...
Article
Full-text available
This article provides a first investigation on the attitude of South Tyrolean residents (northern Italy) toward the return of the wolf in their province. Data were collected through an online questionnaire, which was available for 54,527 residents (≥ 18 years old) of South Tyrol with internet access and a Facebook® account and was shared on the institute’s homepage. In total, 1818 valid responses were collected in 2 months in 2018. Cluster analysis evidenced four homogenous groups of respondents characterized by the components of attitude, their district community, the wolf distribution in their area, belief factors, and the personal fear of wolves. The data analysis revealed differences and relations between the four clusters in the level of knowledge, experience with wolves, education level, and the expected impact on the tourist sector. The obtained results (1) evidence some key factors influencing the attitude of residents, (2) underline the importance of considering small spatial scale attitudinal differences, and (3) urge for an extended human dimension of wolf coexistence research to support local management strategies.
... This is mostly aggravated in areas where wild prey diversity and density is low a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 [6]. However, in the last decades, due to legal protection policies [4], natural recolonization [8] and wild ungulate increase [9], [10], wolf populations have recovered and are now expanding their ranges across some countries in Europe [1], [4], [5], [11]. ...
Article
Full-text available
The Iberian wolf (Canis lupus signatus) is a top predator that inhabits the Iberian Peninsula. In Portugal, its numbers and distribution declined throughout the 20th century, due to human persecution, habitat degradation and prey decline, which have led to higher predation rates of livestock in the remaining packs. In Montesinho Natural Park (northeast Portugal), wild ungulate populations have been increasing in the last years, which may have led wolf to predate upon them. In order to assess Iberian wolf diet in this area, 85 wolf scats were collected from transects distributed throughout the study area in two periods between November 2017 and August 2019. Scat analysis indicated a high predation on wild ungulates, where the frequency of occurrence showed that roe deer was the most consumed prey (44%), followed by red deer (26%) and wild boar (24%). Domestic/wild cat (6%), domestic goat and stone marten (5%) were consumed in lower quantities. It was found a higher selection towards roe deer (D = 0.71) and this was the only prey item which was significantly dependent of the season of the year (χ² = 16.95, df = 3, p < 0.001). This is the first study in Portugal where was recorded that wolves feed mainly on wild ungulates. We conclude that lower livestock predation may be correlated with higher wild ungulates densities in our study area, as well as suitable husbandry practices, leading to a shift on Iberian wolf diet from mainly livestock on previous studies to wild ungulates.
... The outputs of these risk models are used to identify highpriority locations in which to apply conflict intervention or mitigation efforts around the world, thus informing preventative action to maximize impact and minimize cost (Marucco and Mcintire, 2010;Treves et al., 2011;Miller, 2015). Notably, the exact processes at play may differ depending on the ecological community, human culture, and environmental characteristics of the study location. ...
Article
Full-text available
Carnivore depredation of livestock is a global problem which negatively impacts both agropastoral livelihoods and carnivore population viability. Given the gravity of this issue, research has increasingly focused on applied techniques capable of quantifying the factors that increase the risk of livestock depredation. One such technique is risk modeling. This multivariate approach is designed to produce predictions of the spatial configuration of depredation so as to prioritize interventionist activities. Thus, the efficacy of subsequent interventions is, in part, dependent upon the accuracy of the predictions deriving from the risk models. The predictability of spatial patterns in carnivore depredation of livestock is influenced by the degree of spatial autocorrelation evident in the data distributions. We conducted a multi-year assessment to quantify the degree of spatial autocorrelation within livestock depredation data. We centered our study in the Maasai steppe of Tanzania, which experiences some of the highest rates of human-carnivore conflict in the world. We applied three geostatistical measures to assess spatial clustering in data describing livestock depredation by lions (Panthera leo), leopards (Panthera pardus), spotted hyenas (Crocuta crocuta), black-backed jackals (Canis mesomelas), and cheetahs (Acinonyx jubatus) at the household (i.e., livestock enclosure) scale. Using an ordinal spatial scan statistic, a Bernoulli spatial scan statistic, and the Getis-Ord local spatial statistic, we found that the spatial patterns in carnivore depredation of livestock tended not to significantly differ from random. As the predictive ability of spatial risk models may be limited where spatial patterns of carnivore depredation of livestock do not statistically differ from random, explicitly assessing such patterns is an important component of conflict mitigation efforts. We discuss the inferences of this analysis for the optimization of interventionist activities intending to develop sustainable solutions for human-carnivore conflict.
... Since the end of the 1970s, the wolf has been legally protected in Italy, with the prohibition against 93 targeting wolves with poison coming into effect in 1976, and in Europe through the Bern 94 Convention in 1979 (Valière et al., 2003). In the late eighties, the wolf population recovered rapidly 95 in Italy (Fabbri et al., 2007;Marucco and McIntire, 2010). The wolf has never been the subject of 96 reintroduction, repopulation or introduction programmes in Italyor in Europe,in contrast to North 97 ...
Article
Full-text available
In Italy, the recent wolf expansion process is the result of a series of historical, natural, ecological and conservation related factors that have characterized the Italian environmental context during the last few decades. The difficulties in broaching the environmental management of the wolf species have increased economic conflicts, mainly with livestock farmers. To facilitate and pacify the debate, an assessment of the risk of wolf attacks on livestock farms in Umbria’s municipalities needed to be carried out. For this assessment, AHPSort II, a new multi-criteria sorting method for a large number of alternatives, has been developed. This is used for sorting the alternatives into predefined, ordered risk categories. It requires far fewer comparisons than its predecessor, AHPSort. This sorting method can be applied to different environmental problems that have a large number of alternatives. In our case study, AHPSort II requires only 1.4% of the comparisons that would have been required by AHPSort. Combined with clustering, only 0.54% of the comparisons are required. The resulting map shows that a high number of municipalities are at risk, especially those near protected areas.
Article
The Apennine wolf (Canis lupus italicus, Altobello, 1921) is currently experiencing a period of great population change. Any information that helps to understand this transformation will be valuable for managing it. Here we provide, for the first time, quantitative data (habitat suitability, segregation, seasonal activity, daily time budget, social structure and sex-ratio) on the population of Italian wolf from the Cilento, Vallo di Diano and Alburni National Park, the largest protected area in Italy, that houses a rising population. Using transects to locate signs and traces, we have identified 224 presence points, useful for elaborating the ecological suitability map for the wolf, in and around the Park. The suitable area expands up to 1042.65 km 2 , with elevation being the strongest predictive variable affecting the species. The model predicts two main suitable patches (Alburni Mountains and Cervati/Motola Mountains), and at least seven remote areas, differently linked to each other by ecological corridors. Camera-trapping information was collected in the two suitable patches (Alburni and Cervati/Motola) for the wolf and revealed some characteristics of this population. The highest number of wolves was recorded in May and December, and during the night, depending on the reproductive behavior and dynamic of dispersion. Single individuals and couples (at least 3 recorded) are observed more frequently than groups (maximum of 3 groups that varied from three to eight individuals). The sex-ratio in the population, inferred by camera-trapping, showed a balanced population, with males found to be group leader in 91% of the cases. Furthermore, genetic analysis revealed that the males were in charge of marking the territory in 86% of cases. Our data increases the knowledge of the wolf population from Cilento, which seemed to have stopped at the 1990s, until now. Our contribution could be helpful in defining a wolf management strategy in the National Park, as well as in the other regions of the Apennine mountains and Alps, where the wolf is expanding, aiming also at coexistence with local human communities.
Thesis
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Wolves (Canis lupus) in Croatia are estimated at nearly 200 individuals and form part of the Dinaric-Balkan population. As in most of Europe, they are currently expanding in size and distribution. However, the wolf still faces threats that could hamper its viability. In Croatia, these threats include the worsening of public attitudes and the construction of wind power plants in their distribution range. In order to meet the 2020 European targets for renewable energy production, the Republic of Croatia is planning to build 33 wind farms, with a total installed capacity of 1,555 MW. However, in order to meet such targets, only 747.25 MW are necessary. In this study a suitability model for wolf breeding habitat was carried out using Maxent based on 6 environmental variables and 31 homesite locations collected between 1997 and 2015. The prediction of habitat suitability was then used to determine the potential impact of proposed wind farms on wolves. Lastly, a wind farm prioritisation process was carried out using the software Marxan. This allowed selecting the wind farms that contributed to the meeting of the energy targets at the minimum ecological impact on wolf breeding habitat. The model showed good performance (AUC=0.805) and its prediction was consistent with the current knowledge and distribution of wolves in Croatia. The main predictors for suitability were distance to settlements, distance to farmland, distance to roads and distance to forest edge. Moreover, Marxan allowed the selection of highly cost-efficient wind farms. In fact, in the best scenario, selected wind farms were 44.5% of the total proposed wind farms and held only 23.3% of the total initial cost. In conclusion, this study provides valuable information and useful tools for the conservation of wolves in Croatia. In particular, the habitat suitability map can be used for the implementation of the wolf management plan, for the prevention of human-wildlife conflicts and for future conservation planning. Moreover, the result of the prioritisation will be used to inform the strategic planning of wind farms in Croatia. Lastly, the framework adopted in this study can be expanded to multiple infrastructure and multiple large carnivores’ species such as the Eurasian brown bear and the Eurasian lynx.
Preprint
While large carnivores are recovering in Europe, assessing their distributions can help to predict and mitigate conflicts with human activities. Because they are highly mobile, elusive and live at very low density, modeling their distributions presents several challenges due to i) their imperfect detectability, ii) their dynamic ranges over time and iii) their monitoring at large scales consisting mainly of opportunistic data without a formal measure of the sampling effort. Not accounting for these issues can lead to flawed inference about the distribution. Here, we focused on the wolf ( Canis lupus ) that has been recolonizing France since the early 90’s. We evaluated the sampling effort a posteriori as the number of observers present per year in a cell based on their location and professional activities. We then assessed wolf range dynamics from 1993 to 2014, while accounting for species imperfect detection and time- and space-varying sampling effort using dynamic site-occupancy models. Ignoring the effect of sampling effort on species detectability led to underestimating the number of occupied sites by 50% on average. Colonization increased with increasing number of occupied sites at short and long-distances, as well as with increasing forest cover, farmland cover and mean altitude. Colonization decreased when high-altitude increased. The growth rate, defined as the number of sites newly occupied in a given year divided by the number of occupied sites in the previous year, decreased over time, from over 100% in 1994 to 5% in 2014. This suggests that wolves are expanding in France but at a rate that is slowing down. Our work shows that opportunistic data can be analyzed with species distribution models that control for imperfect detection, pending a quantification of sampling effort. Our approach has the potential for being used by decision-makers to target sites where large carnivores are likely to occur and mitigate conflicts.
Article
Full-text available
While large carnivores are recovering in Europe, assessing their distributions can help to predict and mitigate conflicts with human activities. Because they are highly mobile, elusive and live at very low density, modeling their distributions presents several challenges due to i) their imperfect detectability, ii) their dynamic ranges over time and iii) their monitoring at large scales consisting mainly of opportunistic data without a formal measure of the sampling effort. Here, we focused on wolves (Canis lupus) that have been recolonizing France since the early 90’s. We evaluated the sampling effort a posteriori as the number of observers present per year in a cell based on their location and professional activities. We then assessed wolf range dynamics from 1994 to 2016, while accounting for species imperfect detection and time- and space-varying sampling effort using dynamic site-occupancy models. Ignoring the effect of sampling effort on species detectability led to underestimating the number of occupied sites by more than 50% on average. Colonization appeared to be negatively influenced by the proportion of a site with an altitude higher than 2500m and positively influenced by the number of observed occupied sites at short and long-distances, forest cover, farmland cover and mean altitude. The expansion rate, defined as the number of occupied sites in a given year divided by the number of occupied sites in the previous year, decreased over the first years of the study, then remained stable from 2000 to 2016. Our work shows that opportunistic data can be analyzed with species distribution models that control for imperfect detection, pending a quantification of sampling effort. Our approach has the potential for being used by decision-makers to target sites where large carnivores are likely to occur and mitigate conflicts. This article is protected by copyright. All rights reserved.
Thesis
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Large carnivores, once widespread across much of Europe, between the nineteenth and twentieth centuries have suffered a dramatic decline that brought them close to extinction in many parts of Europe. Since the '70s, factors such as legal protection, improved habitats quality and mountains depopulation enabled the recovery of several predator populations. Wolf recovery in areas from which was eradicated, or was occasionally present, has been followed by an intensification of the conflict with human activities, in particular with animal husbandry. Many farmers were unprepared to deal with this new situation having abandoned over the years the use of fences, guard dogs and the practice of monitor the stock. This research was carried out within the territory of Grosseto province, where, following the recent expansion of the wolf population, livestock activities and predator range have overlapped again leading to a situation of great conflict. The same problem occurred in different parts of the world, as demonstrated by the growing number of scientific publications on this topic. Although wolf-livestock conflict is a complex issue, its mitigation is partially fostered by damages reduction. This research shows how the analysis of the ecological context helps in preventing livestock losses. In recent years the use of models to predict the depredation risk has grown dramatically, suggesting how this technique will be increasingly applied to take management information to mitigate the human-carnivore conflict. Therefore I proposed a new three-step method to predict wild canid (wolves and wolf-dog hybrids) depredation risk using presence-only data on wild canid detections and confirmed depredation events in the study area. As a first step, wild canids probability of occurrence was predict; second, I made a prediction on where depredation events were more likely to occur; third I performed an ensemble model integrating the two previous models following an ad-hoc procedure. Models’ outputs obtained from two different approaches to species distribution modeling: Maximum Entropy (Maxent), widely used, and Bayesian for Presence Only Data (BPOD), recently proposed, were compared testing their ability to predict the occurrence of events. The ecological niche factor analysis (ENFA) was used to assess the importance of each environmental variable in the description of the presence points. Results showed that the presence of wild canids was mainly related to forests (M = 0.78). Whereas depredation events were most likely to occur close to farms (M = -0.83) where sheep densities were higher (M = 8.1) and more accessible (M = -1.46). Higher depredation risk zones were characterized by proximity to forested areas and the presence of landscape features that allowed wild canids to reach pastures with minimum effort such as the network of smaller watercourses. Although the majority of livestock within Grosseto province graze extensively and is thus potentially available for predators, only 15% sheep farms fall within higher risk areas. This suggests that at the provincial level, depredation was facilitated by environmental conditions (e.g. closeness to the woods or steams) rather than the availability of domestic prey. Overall BPOD performed better than Maxent in terms of sensitivity, suggesting that BPOD could be a promising approach to predict probability of occurrence using presence-only data. In many parts of the world, livestock guarding dogs (LGDs) are considered one of the most powerful prevention tools against carnivore depredation on domestic animals. As wolf populations are recovering their use is expected to increase. Although LGDs defend livestock against predators, they could negatively impact on some wild species and in some situations could be even a potential hazard to humans. Therefore how these dogs behave when left unsupervised with their flock on pastures is of utmost importance. 29 LGDs with GPS collars were monitored in order to investigate their space use and association with their livestock, analyzing two parameters: the dog-sheep distance and the overlap between dog and sheep movement ranges. The first parameter was evaluated by measuring the real distance between pairs of dog-sheep locations taken in less than five minutes apart to ensure the simultaneity of the two events. In addition linear mixed models were implemented to evaluate how dog-sheep distance was influenced by environmental, dog-related, and farming-related variables. UDOI (Utilization Distribution Overlap Index) and the VI (Volume of Intersection) Index for 50% and 95% kernel isopleths were calculated to quantify the overlap and the similarity in the use of space for the core area and for the whole movement range of sheep and dogs. Finally the usefulness of GPS pet collars in dogs and sheep husbandry was tested. LGDs did not leave the flock unattended when left unsupervised. They spent the majority of their time close to livestock, sharing the same areas but using the space in a different way (mean VI 95% = 0.65 ± 0.16; mean UDOI 95%= 1.31 ± 0.56). Dog-sheep distance was mostly influenced by environmental variables and the age of the dog. Dogs and sheep tended to separate more in pastures surrounded by woods (β = 1.669, p <2.2e-16) or located in heterogeneous agricultural areas (β = 1.204, p = 1.33e-05), and less in pastures close to inhabited areas (β = -1.730, p = 2.34e-07). Older dogs were more associated to the flock compared to younger individuals (β = -0.438, p = 0.002). Some of the variability linked to the dog-sheep distance was explained by the importance of the random components of the models, namely: the differences among individual dogs working in pastures with different extension (p<2.2e-16); the day when the sampling was done (p<2.2e-16); and the differences among farms (p=4.87e-07). The effectiveness of guarding dogs as a prevention tool is not only affected by the environmental features or by LGD’s characteristics and training. In fact, to be effective, livestock guarding dogs should work in conditions that allow them to protect the entire livestock. Comparing 79 sheep farms with at least one adult (> 1.5 years old) guarding dog, were highlighted the conditions that decrease the efficacy of these animals in reducing depredations. For each farm were measured: 1) the number of adult livestock guarding dogs; 2) the distance between the farmer's house and the night shelter; 3) night shelter permeability to predators; 4) flock size; 5) shepherd presence; 6) the number of depredation events over the last six months; 7) the depredation risk. Farms were classified on whether or not they experienced depredation over the last six months. The two groups were then compared using non-parametric tests and logistic regressions. Depredated and non-depredated farms differed only by the night shelter-farmer’s home distance value (W = 455, p-value = 0.005). The model averaging showed a significant positive correlation between damage occurrence and night shelter-farmer’s home distance length (β = 4.695 e-04, p-value = 0.0218). These results suggest that in environmental conditions that determine a similar depredation risk, human presence is the main feature that enhances the effectiveness of guarding dogs as a tool against canid attacks on flocks. Investigating the role of some of the ecological variables involved in depredation events helps to ensure that the wolf-livestock interactions occur in a sustainable manner. Indeed depredation risk maps could be a useful tool for farmers and manager for the timely apply prevention techniques that reduce depredation and for policymaker could be a support to allocate financial resources. Additionally conservation projects may benefit from these maps to select areas of intervention. Moreover results from this work provided some hints for farmers and conservationists to improve the use of LGDs for an effective livestock protection: some of the recommendations affected the dog management, while other the livestock husbandry practices. Finally this research introduced a new way to manage LGDs using GPS pet collars. With these devices farmers could be able to check the position of their dogs and their flock at any time, preventing wrong dog behaviors, conflicts with neighbors and accidents.
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1. Reliable estimates of population parameters are often necessary for conservation management but these are hard to obtain for elusive, rare and wide-ranging species such as wolves Canis lupus. This species has naturally recolonized parts of its former habitat in Western Europe; however, an accurate and cost-effective method to assess population trend and survival has not been implemented yet. 2. We used open-model capture–recapture (CR) sampling with non-invasive individual identifications derived from faecal genotyping to estimate survival and trend in abundance for wolves in the Western Alps between 1999 and 2006. Our sampling strategy reduced individual heterogeneity in recaptures, thus minimizing bias and increasing the precision of the estimates. 3. Young wolves had lower apparent annual survival rates (0·24 ± 0·06) than adult wolves (0·82 ± 0·04); survival rates were lower in the summer than in the winter for both young and adults. The wolf population in the study area increased from 21 ± 9·6 wolves in 1999 to 47 ± 11·2 wolves in late winter 2005; the population growth rate (λ = 1·04 ± 0·27) was lower than that recorded for other recolonizing wolf populations. 4. We found a positive trend in wolf abundance, regardless of the method used. However, the abundance estimate based on snow-tracking was on average 36·2% (SD = 13·6%) lower than that from CR modelling, because young dispersing wolves are likely to have lower sign detection rates in snow-track surveys, a problem adequately addressed by CR sampling. 5. Synthesis and applications. We successfully implemented a new method to assess large carnivore population trend and survival at large spatial scales. These are the first such estimates for wolves in Italy and in the Alps and have important management implications. Our approach can be widely applied to broader spatial and temporal scales for other elusive and wide-ranging species in Europe and elsewhere.
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Resource-selection probability functions and occupancy models are powerful methods of identifying areas within a landscape that are highly used by a species. One common design/analysis method for estimation of a resource-selection probability function is to classify a sample of units as used or unused and estimate the probability of use as a function of independent variables using, for example, logistic regression. This method requires that resource units are correctly classified as unused (i.e., the species is never undetected in a used unit), or that the probability of misclassification is the same for all units. In this paper, I explore these issues, illustrating how misclassifying units as unused may lead to incorrect conclusions about resource use. I also show how recently developed occupancy models can be utilized within the resource-selection context to improve conclusions by explicitly accounting for detection probability. These models require that multiple surveys be conducted at each of a sample of resource units within a relatively short timeframe, but given the growing evidence from simulation studies and field data, I recommend that such procedures should be incorporated into studies of resource use.
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1. Restoring biologically appropriate habitat networks is fundamental to the persistence and connectivity of at-risk species surviving in highly fragmented environments. For many at-risk species, this landscape planning problem requires combining detailed biological information about the species with the landscape, economic and social realities of the restoration effort. 2. Here, we assess the ability of potential restored landscapes to create persistent and connected populations of the federally endangered Fender's blue butterfly (Icaricia icarioides fenderi) in Oregon's Willamette Valley. Like many other at-risk species, a very small amount (0·5%) of historic habitat remains and much of this habitat is highly degraded. 3. To do this, we combine extensive demography and behaviour data from prior studies of Fender's blue with landscape maps of potential restoration sites by building and running a spatially explicit landscape model. We chose a simulation approach because previous attempts using more traditional population modelling did not provide sufficiently informative answers for this restoration problem. 4. From our simulations, we: (a) provide a solution to the general landscape restoration problem of determining whether patches that are available according to social, economic and ecological realities are sufficient to restore persistence and connectivity; (b) supported our predictions from our previous models about persistence of our large patches and expanded our inference to include connectivity and persistence of small patches; and (c) found several emergent properties of our system, including identifying stepping-stone patches, observing asymmetric connectivity and uncovering reciprocal effects of connectivity and population dynamics. 5. Synthesis and applications. Assuming no large disturbances, and relying on our 14 years of data collection and models, restoring all currently degraded and potentially available habitat patches to high quality native prairie would be sufficient for long-term persistence of Fender's blue butterfly in the West Eugene area, Oregon. This conclusion resolves many of the shortcomings of our previous population and metapopulation models that were not able to combine the necessary landscape complexity with species behaviour to address this restoration problem.
Article
Summary • Although many reintroduction schemes for the Eurasian lynx Lynx lynx in Germany have been discussed, the implications of connectivity between suitable patches have not been assessed. • We introduce an individual-based, spatially explicit dispersal model to assess the probability of a dispersing animal reaching another suitable patch in the complex heterogeneous German landscape, with its dense transport system. The dispersal model was calibrated using telemetric data from the Swiss Jura and based on a map of potential lynx dispersal habitat. • Most suitable patches could be interconnected by movements of dispersing lynx within 10 years of reintroduction. However, when realistic levels of mortality risks on roads were applied, most patches become isolated except along the German–Czech border. Consequently, patch connectivity is limited not so much by the distribution of dispersal habitat but by the high mortality of dispersing lynx. Accordingly, rather than solely investing in habitat restoration, management efforts should try to reduce road mortality. • Synthesis and applications. Our approach illustrates how spatially explicit dispersal models can guide conservation efforts and reintroduction programmes even where data are scarce. Clear limits imposed by substantial road mortality will affect dispersing lynx as well as other large carnivores, unless offset by careful road-crossing management or by the careful selection of release points in reintroduction programmes. Journal of Applied Ecology (2004) 41, 711–723
Article
ABSTRACT  The isolated gray wolf (Canis lupus) population of the Scandinavian Peninsular is suffering from inbreeding depression. We studied dispersal of 35 wolves fitted with very high frequency (20) or Global Positioning System—global system for mobile (15) radiocollars in the neighboring Finnish wolf population. The growing wolf population in Finland has high numbers of dispersing individuals that could potentially disperse into the Scandinavian population. About half (53%) of the dispersing wolves moved total distances that could have reached the Scandinavian population if they had been straight-line moves, but because of the irregular pattern of movements, we detected no wolves successfully dispersing to the Scandinavian population. Dispersal to the Scandinavian population was also limited by high mortality of wolves in reindeer (Rangifer tarandus) management areas and by dispersal to Bothnian Bay at times of the year when ice was not present. We suggest that when a small wolf population is separated from source populations by distance, barriers, and human exploitation, wildlife managers could promote the population's viability by limiting harvest in the peripheral areas or by introducing wolves from the source population.
Article
Aim To explore the usefulness of Spatially Explicit Population Models (SEPMs), incorporating dispersal, as tools for animal conservation, as illustrated by the contrasting cases of four British mammals.Methods For each of the four species (American mink, Mustela vison, pine marten, Martes martes, dormouse, Muscardinus avellanarius and water vole, Arvicola terrestris) a spatial dynamics model was developed based on an integrated geographical information system (GIS) population model that linked space use to the incidence of the species. Each model had, first, a GIS, which stored environmental, habitat and animal population information, and secondly, an individual-based population dynamics module, which simulated home range formation, individual life histories and dispersal within the GIS-held landscape.Results The four models illustrated different interactions between species life-history variables and the landscape, particularly with respect to dispersal. As water voles and dormice occupy home ranges that are small relative to blocks of their habitat, they were most effectively modelled in terms of the dynamics of local populations within habitat blocks but linked by dispersal. In contrast, because the home ranges of American mink and pine marten are large relative to blocks of habitat, they were best modelled as individuals moving through a landscape of more or less useful patches of habitat. For the water vole, the most significant predictors of population size were the carrying capacity of each habitat and the annual number of litters. For the dormouse, the likelihood of catastrophe and the upper limit to dispersal movement were the key variables determining persistence. Adult mortality and home-range size were the only significant partial correlates of total population size for the American mink. Adult mortality was also a significant correlate of total population size in the pine marten, as were litter size and juvenile mortality. In neither the marten nor the mink was dispersal distance a significant factor in determining their persistence in the landscape.Main conclusions At a landscape scale it is difficult to measure animal distributions directly and yet conservation planning often necessitates knowledge of where, and in what numbers, animals are found, and how their distributions will be affected by interventions. SEPMs offer a useful tool for predicting this, and for refining conservation plans before irreversible decisions are taken in practice.