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  • 1. Belton, L. E.
    et al.
    Cameron, E. Z.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spain.
    Anthropogenic influences on spotted hyaena diet in the Kruger National Park, South Africa2018Ingår i: Mammal Research, ISSN 2199-2401, E-ISSN 2199-241X, Vol. 63, nr 3, s. 315-323Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rapid urban expansion has led to an increase in carnivores that live close to human dominated environments. Some carnivore species have successfully adapted to these novel conditions and taken advantage of opportunities associated with human habitation. Whilst many studies have compared carnivores living in protected areas to those in an urban setting, few have looked at the relationships between carnivores and human habitation within protected areas. In this study, we examined the effects ofhuman habitation on the diet of spotted hyaenas (Crocuta crocuta) in the Kruger National Park (KNP), South Africa. Our results suggested a limited effect of anthropogenic resources on spotted hyaena diet in the KNP. We found neither temporal nor spatial variation in the amount of, nor types of, anthropogenic material in spotted hyaena scats, despite observations of more road side litter close to large anthropogenic sites. We therefore suggest that anthropogenic resources may not have been utilised completely according to abundance. We encourage further research evaluating potential secondary effects of human activity and infrastructure on spotted hyaena diet and also stable isotope approaches that may provide further insights into the importance of anthropogenic food for spotted hyaenas inside the KNP.

  • 2. Belton, L. E.
    et al.
    Cameron, E. Z.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spain.
    Spotted hyaena visitation at anthropogenic sites in the Kruger National Park, South Africa2018Ingår i: African Zoology, ISSN 1562-7020, E-ISSN 2224-073X, Vol. 53, nr 3, s. 113-118Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many large carnivores are attracted to anthropogenic sites, typically, because they offer easy access to anthropogenic resources, such as garbage. Such behaviour could lead to increased contacts between people and carnivores, with the potential for escalated conflicts. Within protected areas, carnivores experience limited risks of visiting anthropogenic sites. However, conflict could still arise, so that it is important to evaluate the drivers for visitation within protected areas. We tested how age, sex and social rank influenced seasonal visitation rates by spotted hyenas (Crocuta crocuta) at two sites with elevated human activity and infrastructure within the Kruger National Park, South Africa. Social rank did not influence visitation rates, and differences among age classes did not correspond to differences in abilities to procure native food. Instead, juveniles had higher visitation rates than older individuals, but only during the wet season. Visitation rates were not consistently higher during the dry season, nor was there more pronounced differences between age classes in the dry season. Our results suggest the anthropogenic sites were visited as part of exploratory behaviour coupled with occasional rewards. Our study also showed a large individual variation in tendencies towards visiting anthropogenic sites, but only for younger animals. We call for additional studies quantifying individual variation in tendencies to visit anthropogenic sites, and argue that deterrents and limitations in rewards of visiting anthropogenic sites might be efficient in preventing human-hyaena conflict within the Kruger National Park.

  • 3. Belton, Lydia E.
    et al.
    Cameron, Elissa Z.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spain.
    Social networks of spotted hyaenas in areas of contrasting human activity and infrastructure2018Ingår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 135, s. 13-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In group-living animals, the structure of social interactions among group members can have important consequences for individual fitness. Changes in resource abundance can influence social interactions with an expected weakening of social ties during times of resource scarcity. Although human activity and infrastructure often impose a disturbance on animal populations, they can also be a source of reliable resources that are relatively easy to access. We evaluated whether the social networks differed between four spotted hyaena, Crocuta crocuta, clans experiencing contrasting levels of human activity and infrastructure in the Kruger National Park, South Africa. The clan living in an area of high human activity and infrastructure had a less dense social network than the other clans, and the clan living in an area with limited human activity and infrastructure had shorter path lengths than the other clans, suggesting that it had more closely associated individuals. Our results did not support substantial differences between clans in the relative social network positions of animals from different age and rank classes. Contrary to our expectations, we suggest that anthropogenic resources may have weakened the social cohesiveness within spotted hyaena clans. We also argue that our study supports previous suggestions that there may be individual variation within broader classes of rank, age and sex in the position of individual animals in social networks.

  • 4. Belton, Lydia E.
    et al.
    Cameron, Elissa Z.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spa.
    Spotted hyaena space use in relation to human infrastructure inside a protected area2016Ingår i: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 4, artikel-id e2596Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Increasing human population growth has led to elevated levels of human-carnivore conflict. However, some carnivore populations have adapted to urban environments and the resources they supply. Such associations may influence carnivore ecology, behaviour and life-history. Pockets of urbanisation sometimes occur within protected areas, so that anthropogenic influences on carnivore biology are not necessarily confined to unprotected areas. In this study we evaluated associations between human infrastructure and related activity and space use of spotted hyaenas within one of the largest protected areas in South Africa, the Kruger National Park. Home range size was smaller for the dominant female of a clan living in close proximity to humans than that of the dominant female of a clan without direct access to human infrastructure. The home range including human infrastructure was also used less evenly during the night, presumably when the animals were active. Within this home range, a village area was preferred during the night, when the least modified areas within the village were preferred and administration and highly modified areas were avoided. During the day, however, there were no preference or avoidance of the village area, but all habitats except unmodified habitats within the village area were avoided. We suggest that human infrastructure and associated activity influenced hyaena space use, primarily through alterations in the spatial distribution of food. However, these effects may have been indirectly caused by habitat modification that generated favourable hunting habitat rather than a direct effect caused by access to human food such as garbage. Because of the often pivotal effects of apex predators in terrestrial ecosystems, we encourage further work aimed to quantify how human presence influences large carnivores and associated ecosystem processes within protected areas.

  • 5.
    Chizzola, Maddalena
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Belton, Lydia
    Ganswindt, Andre
    Greco, Ilaria
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Hall, Grant
    Swanepoel, Lourens
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spai.
    Landscape Level Effects of Lion Presence (Panthera leo) on Two Contrasting Prey Species2018Ingår i: Frontiers in Ecology and Evolution, E-ISSN 2296-701X, Vol. 6, artikel-id 191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to the strong individual cost of being predated, potential prey species alter their behavior and physiology in response to predation risk. Such alterations may cause major indirect consequences on prey populations that are additive to the direct demographic effects caused by prey being killed. However, although earlier studies showed strong general effects of the presence of apex predators, recent data suggest that indirect effects may be highly context dependent and not consistently present. We combined behavioral data with data on endocrine stress and stable isotopes to assess landscape level effects of lion (Panthera leo) presence on two prey species in South Africa, impala (Aepyceros melampus) and blue wildebeest (Connochaetes taurinus). We also evaluated if there was any seasonal variation in such effects. In addition, we provide results from a physiological validation for an enzyme-linked immunoassay (EIA) that can be used for non-invasive monitoring of glucocorticoid stress metabolite concentrations in impala from fecal pellets. We did not find any significant differences in vigilance behavior, fecal glucocorticoid metabolite concentrations, delta C-13 values or isotope niche breadth between animals living with and without lions for either species. However, wildebeest living in a reserve with lions spent more time foraging compared to wildebeest in a lion-free environment, but only during the wet season. Values of fecal delta N-15 suggest a shift in habitat use, with impala and wildebeest living with lions potentially feeding in less productive areas compared to animals living without lions. For both species, characteristics of the social groups appeared to be more important than individual characteristics for both foraging and vigilance behavior. Our results highlight that antipredator responses may be highly dynamic and scale-dependent. We urge for further studies that quantify at what temporal and spatial scales predation risk is causing indirect effects on prey populations.

  • 6.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Dalén, Love
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Fröjd, Christina
    Lecomte, Nicolas
    Lindgren, Åsa
    Meijer, Tomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Pečnerová, Patrícia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Spatial variation in Arctic hare (Lepus arcticus) populations around the Hall Basin2017Ingår i: Polar Biology, ISSN 0722-4060, E-ISSN 1432-2056, Vol. 40, nr 10, s. 2113-2118Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Arctic environments have relatively simple ecosystems. Yet, we still lack knowledge of the spatio-temporal dynamics of many Arctic organisms and how they are affected by local and regional processes. The Arctic hare (Lepus arcticus) is a large lagomorph endemic to high Arctic environments in Canada and Greenland. Current knowledge about this herbivore is scarce and the temporal and spatial dynamics of their populations are poorly understood. Here, we present observations on Arctic hares in two sites on north Greenland (Hall and Washington lands) and one adjacent site on Ellesmere Island (Judge Daly Promontory). We recorded a large range of group sizes from 1 to 135 individuals, as well as a substantial variation in hare densities among the three sites (Hall land: 0 animals/100 km(2), Washington land 14.5-186.7 animals/100 km(2), Judge Daly Promontory 0.18-2.95 animals/100 km(2)). However, pellet counts suggested that both Hall land and Judge Daly Promontory hosted larger populations at other times. We suggest that our results could have been caused by three spatially differentiated populations with asynchronous population fluctuations. With food limitation being a likely driver behind the observed variation, we argue that food limitation likely interacts with predation and competition in shaping the spatial dynamics of Arctic hares in this region.

  • 7.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    de Vries, J. Low
    Pirk, Christian W. W.
    Cameron, Elissa Z.
    Spatial and temporal dimensions to the taxonomic diversity of arthropods in an arid grassland savannah2017Ingår i: Journal of Arid Environments, ISSN 0140-1963, E-ISSN 1095-922X, Vol. 144, s. 21-30Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quantifying the drivers of biodiversity variation is a key topic in contemporary ecology. While the geographic distribution of biodiversity is broadly determined by water and energy, local environmental conditions may be important. We evaluated the relative effects of spatial and temporal variation on taxonomic diversity of ground living arthropod communities in central South Africa. Seasonal climate variation was a major driver of arthropod abundance, but seasonal effects differed between habitats. We did not find any evidence for modular community structures, even across different habitats, or any evidence for a nested pattern across seasons. Instead, we observed a spatial nestedness which was only partly related to specific habitats. Our results suggest that neutral processes had influenced arthropod community structure, but also that very local processes may have been pivotal in determining local and regional arthropod diversity. Such processes may not necessarily have been neutral, but could have been caused by niche deterministic processes acting at scales smaller the distinct habitat classes we used for our study. We further suggest that alterations in climate likely will have substantial effects on the spatial and temporal distribution of arthropod diversity in this arid region.

  • 8.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Freire, S.
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Lecomte, N.
    Lindgren, A.
    Meijer, Tomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Pečnerová, Patricia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Dalén, Love
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Exploring the diet of arctic wolves (Canis lupus arctos) at their northern range limit2018Ingår i: Canadian Journal of Zoology, ISSN 0008-4301, E-ISSN 1480-3283, Vol. 96, nr 3, s. 277-281Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The grey wolf (Canis lupus Linnaeus, 1758) is one of the most widespread large carnivores on Earth, and occurs throughout the Arctic. Although wolf diet is well studied, we have scant information from high Arctic areas. Global warming is expected to increase the importance of predation for ecosystem regulation in Arctic environments. To improve our ability to manage Arctic ecosystems under environmental change, we therefore need knowledge about Arctic predator diets. Prey remains in 54 wolf scats collected at three sites in the high Arctic region surrounding the Hall Basin (Judge Daly Promontory, Ellesmere Island, Canada, and Washington Land and Hall Land, both in northwestern Greenland) pointed to a dietary importance of arctic hare (Lepus arcticus Ross, 1819; 55% frequency of occurrence) and muskoxen (Ovibos moschatus (Zimmermann, 1780); 39% frequency of occurrence), although we observed diet variation among the sites. A literature compilation suggested that arctic wolves (Canis lupus arctos Pocock, 1935) preferentially feed on caribou (Rangifer tarandus (Linnaeus, 1758)) and muskoxen, but can sustain themselves on arctic hares and Greenland collared lemmings (Dicrostonyx groenlandicus (Traill, 1823)) in areas with limited or no ungulate populations. We suggest that climate change may alter the dynamics among wolves, arctic hare, muskoxen, and caribou, and we encourage further studies evaluating how climate change influences predator-prey interactions in high Arctic environments.

  • 9.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Hellström, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Miranda, M.
    Nyström, Jesper
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Ekenstedt, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Network topology of stable isotope interactions in a sub-arctic raptor guild2016Ingår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 182, nr 2, s. 511-518Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Predation is an ecologically important process, and intra-guild interactions may substantially influence the ecological effects of predator species. Despite a rapid expansion in the use of mathematical graph theory to describe trophic relations, network approaches have rarely been used to study interactions within predator assemblages. Assemblages of diurnal raptors are subject to substantial intra- and interspecific competition. Here we used the novel approach of applying analyzes based on network topology to species-specific data on the stable isotopes C-13 and N-15 in feathers to evaluate patterns of relative resource utilization within a guild of diurnal raptors in northern Sweden. Our guild consisted of the golden eagle (Aquila chrysaetos), the gyrfalcon (Falco rusticolus), the peregrine falcon (Falco peregrinus) and the rough-legged buzzard (Buteo lagopus). We found a modular trophic interaction structure within the guild, but the interactions were less nested than expected by chance. These results suggest low redundancy and hence a strong ecological importance of individual species. Our data also suggested that species were less connected through intra-guild interactions than expected by chance. We interpret our results as a convergence on specific isotope niches, and that body size and different hunting behaviour may mediate competition within these niches. We finally highlight that generalist predators could be ecologically important by linking specialist predator species with disparate dietary niches.

  • 10.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Miranda, Maria
    Game auction prices are not related to biodiversity contributions of southern African ungulates and large carnivores2016Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, artikel-id 21922Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is an urgent need for human societies to become environmentally sustainable. Because public policy is largely driven by economic processes, quantifications of the relationship between market prices and environmental values can provide important information for developing strategies towards sustainability. Wildlife in southern Africa is often privately owned and traded at game auctions to be utilized for commercial purposes mostly related to tourism. This market offers an interesting opportunity to evaluate how market prices relate to biologically meaningful species characteristics. In this market, prices were not correlated with species contributions to either phylogenetic or functional diversity, and species contributions to phylogenetic or functional diversity did not influence the trends in prices over time for the past 20 years. Since this economic market did not seem to appreciate evolutionary or ecologically relevant characteristics, we question if the game tourism market may contribute towards biodiversity conservation in southern Africa. We suggest that market prices in general may have limited values as guides for directing conservation and environmental management. We further suggest that there is a need to evaluate what humans value in biological organisms, and how potentially necessary shifts in such values can be instigated.

  • 11.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Miranda, Maria
    Muniz, Cristina
    Rodríguez, Placido
    Effects of scarcity, aesthetics and ecology on wildlife auction prices of large African mammals2018Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 47, nr 1, s. 78-85Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For successful integration of biological conservation into economic markets, economic processes need to capture ecological values. South African wildlife ranching is a tourist-based activity that generates unique information on the economic value of wildlife species. We used public data from South African wildlife auctions to evaluate if annual prices 1991-2012 related to species characteristics associated with scarcity, aesthetics and ecology of South African carnivores and ungulates. While none of the species characteristics influenced carnivore prices, ungulate prices were related to characteristics associated with novelty and aesthetics, which relative importance had increased over time. We raise both ecological and economic concerns for this apparent focus. Our results also suggest a potential importance of non-species-related factors, such as market and buyer characteristics. We encourage further evaluation of the relative influences of species characteristics versus factors that are intrinsically linked to economic processes on price variations in South African wildlife.

  • 12.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Retief, Tarryn Anne
    Havemann, Carl Peter
    Chimimba, Christian T.
    van Rensburg, Berndt Janse
    The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 1, s. 154-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Studies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi-arid savanna in northern Botswana. Ant abundance, taxonomic richness, and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small-scale gradients in distance to water can influence several aspects of ant communities in semi-arid savannas. However, our results also point to strong effects of small-scale environmental variation, for instance associated with vegetation characteristics, soil properties, and plant community structure that are not directly linked to water access.

  • 13.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Universidad de Oviedo, Spain; University of Pretoria, South Africa.
    Swanepoel, Lourens H.
    HUMANS AS PREDATORS: AN OVERVIEW OF PREDATION STRATEGIES OF HUNTERS WITH CONTRASTING MOTIVATIONAL DRIVERS2017Ingår i: Arbor, ISSN 0210-1963, E-ISSN 1988-303X, Vol. 193, nr 786, artikel-id a419Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Predator-prey theory suggests that generalist predators are linked to demographic stability of prey whereas specialists are destabilizing. We overview the demographic consequences of different predation strategies and hypothesize that subsistence hunting occurs opportunistically, persecution hunters behave like specialist predators, and recreational hunters behave like generalist predators. Under this hypothesis, persecution hunting would have destabilizing effects, whereas the effects of subsistence and recreational hunting would be neutral or stabilizing. We found poor empirical support for this hypothesis, but there was scarce empirical data. Recreational hunters mainly hunted opportunistically and hunting as managed persecution followed a type III functional response, i.e. with low hunting intensity at low game abundances and a switch to an increased intensity at some level of abundance. We suggest that recreational hunters have limited destabilizing effects on game populations and that hunting may be an ineffective way of complete the removal of invasive species. We urge for further studies quantifying the responses of hunters to game abundances, in particular studies evaluating the responses of subsistence hunters and illegal persecution.

  • 14.
    Eriksson, Therese
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Identifying potential areas for an expanding wolf population in Sweden2018Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 220, s. 170-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Large carnivores have historically been decreasing worldwide, often as a result of human-carnivore conflicts. However, large carnivores are recovering throughout Europe, and European management scenarios can provide important insights into broad issues related to human-large carnivore existence. After becoming almost extinct in Sweden during the mid-19th century the Swedish grey wolf (Canis lupus) population has now recovered. Current national wolf management aims to promote distribution shifts from the current areas in central Sweden, potentially also into a previously exempt reindeer husbandry area. Prior wolf re-introductions have highlighted the necessity of pro-active management for colonization success. Identification of likely range expansion areas could therefore be paramount for a successful Swedish wolf management. We characterized the demographic and spatial progression of Swedish wolves during 2001-2015 and used a MaxEnt approach to species distribution models to identify potential range expansion areas. The Swedish wolf population had expanded from 10 to almost 60 reproductions or territorial pairs, and increased in both range size and density. Our distribution models suggested that Swedish wolf management may face trade-offs between costs of hosting wolves in densely populated areas in southern Sweden with cattle and sheep and the costs of allowing wolves to expand into reindeer husbandry areas with associated cultural and economic consequences. Spatially explicit data on the economic, social and cultural factors associated with wolf conflict and acceptance may be paramount for developing optimal management strategies in the face of such a trade-off.

  • 15. Jumbam, Keafon R.
    et al.
    Périquet, Stéphanie
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    le Roux, Aliza
    Spatial and temporal variation in the use of supplementary food in an obligate termite specialist, the bat-eared fox2019Ingår i: African Zoology, ISSN 1562-7020, E-ISSN 2224-073X, Vol. 54, nr 1, s. 63-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The bat-eared fox (Otocyon megalotis) is considered a termite specialist. However, studies of its diet have been limited to indirect methods, such as scat and stomach content analyses, resulting in intraspecific dietary variations due in part to methodological differences. Because diet plays a central role in the social dynamics of these canids, we hereby contribute further to our knowledge about their dietary habits. We present 2-year data of direct observations of foraging bouts of 19 habituated bat-eared foxes in the kalahari desert of South Africa, as well as data on seasonal variation in invertebrate prey communities obtained through pitfall and sweep net trapping. Despite showing a diet breadth reflective of a specialised forager across all seasons, foxes exhibited substantial seasonal variation in diet breadth with a broader range of food categories utilised in summer compared to the other seasons. Supplementary food categories appear to not have been utilised opportunistically, but it is unclear what drove the preference for some food categories over others. A literature review indicated strong effects of local conditions on the utilisation of supplementary food across southern Africa. Our data support bat-eared foxes as obligate termite specialists but highlight that they appear to have the ability to show dietary flexibility based on both temporal and spatial variations in food abundance.

  • 16. Le Roux, Aliza
    et al.
    Botha, Helene
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Ganswindt, Andre
    Non-invasive measurement of adrenocortical activity in a myrmecophageous mammal, the bat-eared fox2016Ingår i: African Zoology, ISSN 1562-7020, E-ISSN 2224-073X, Vol. 51, nr 1, s. 47-51Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Measuring physiological stress reactions through the quantification of plasma cortisol often involves physical restraint, which acts as a stressor itself. Here, we present the validation of a non-invasive method for assessing adrenocortical activity as an indicator of stress in the bat-eared fox (Otocyon megalotis). By conducting an adrenocorticotropic hormone (ACTH) challenge, we examined the suitability of three enzyme immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (fGCM) with a 5 beta-3 alpha-ol-11-one (3 alpha, 11oxo-CM), or 11,17,21-trihydroxy-4-ene-20-one structure (cortisol), respectively, for monitoring stress-related physiological responses in male and female bat-eared foxes. Our results suggest that the cortisol EIA seems most suitable for measuring fGCMs in this myrmecophageous mammal. Using the cortisol EIA, we compared fGCM concentrations of three populations of foxes. Only one population experienced a sudden change in social environment and the assay appeared to effectively detect the expected resulting increase in stress hormone levels. Therefore, the identified EIA is effective at detecting intraspecific variation in fGCM levels and hence is a useful tool to evaluate physiological stress responses in this species.

  • 17.
    Naud, Lucy
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Måsviken, Johannes
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Freire, Susana
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Dalén, Love
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Oviedo University, Spain; University of Pretoria, South Africa.
    Altitude effects on spatial components of vascular plant diversity in a subarctic mountain tundra2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 8, s. 4783-4795Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Environmental gradients are caused by gradual changes in abiotic factors, which affect species abundances and distributions, and are important for the spatial distribution of biodiversity. One prominent environmental gradient is the altitude gradient. Understanding ecological processes associated with altitude gradients may help us to understand the possible effects climate change could have on species communities. We quantified vegetation cover, species richness, species evenness, beta diversity, and spatial patterns of community structure of vascular plants along altitude gradients in a subarctic mountain tundra in northern Sweden. Vascular plant cover and plant species richness showed unimodal relationships with altitude. However, species evenness did not change with altitude, suggesting that no individual species became dominant when species richness declined. Beta diversity also showed a unimodal relationship with altitude, but only for an intermediate spatial scale of 1km. A lack of relationships with altitude for either patch or landscape scales suggests that any altitude effects on plant spatial heterogeneity occurred on scales larger than individual patches but were not effective across the whole landscape. We observed both nested and modular patterns of community structures, but only the modular patterns corresponded with altitude. Our observations point to biotic regulations of plant communities at high altitudes, but we found both scale dependencies and inconsistent magnitude of the effects of altitude on different diversity components. We urge for further studies evaluating how different factors influence plant communities in high altitude and high latitude environments, as well as studies identifying scale and context dependencies in any such influences.

  • 18. Penteriani, Vincenzo
    et al.
    Del Mar Delgado, Maria
    Krofel, Miha
    Jerina, Klemen
    Ordiz, Andres
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Oviedo University, Spain; University of Pretoria, South Africa.
    Zarzo-Arias, Alejandra
    Bombieri, Giulia
    Evolutionary and ecological traps for brown bears Ursus arctos in human-modified landscapes2018Ingår i: Mammal Review, ISSN 0305-1838, E-ISSN 1365-2907, Vol. 48, nr 3, s. 180-193Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Evolutionary traps, and their derivative, ecological traps, occur when animals make maladaptive decisions based on seemingly reliable environmental cues, and are important mechanistic explanations for declines in animal populations. Despite the interest in large carnivore conservation in human-modified landscapes, the emergence of traps and their potential effects on the conservation of large carnivore populations has frequently been overlooked. The brown bear Ursus arctos typifies the challenges facing large carnivore conservation and recent research has reported that this species can show maladaptive behaviours in human-modified landscapes. Here we review, describe and discuss scenarios recognised as evolutionary or ecological traps for brown bears, and propose possible trap scenarios and mechanisms that have the potential to affect the dynamics and viability of brown bear populations. Six potential trap scenarios have been detected for brown bears in human-modified landscapes: 1) food resources close to human settlements; 2) agricultural landscapes; 3) roads; 4) artificial feeding sites; 5) hunting by humans; and 6) other human activities. Because these traps are likely to be of contrasting relevance for different demographic segments of bear populations, we highlight the importance of evaluations of the relative demographic consequences of different trap types for wildlife management. We also suggest that traps may be behind the decreases in brown bear and other large carnivore populations in human-modified landscapes.

  • 19. Penteriani, Vincenzo
    et al.
    López-Bao, José Vicente
    Bettega, Chiara
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Oviedo University, Spain; University of Pretoria, South Africa.
    del Mar Delgado, María
    Jerina, Klemen
    Kojola, Ilpo
    Krofel, Miha
    Ordiz, Andrés
    Consequences of brown bear viewing tourism: A review2017Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 206, s. 169-180Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Many countries promote wildlife observation as part of ecotourism offerings. The brown bear Ursus arctos is among the most targeted species for ecotourism in Notth America and Europe, making it an ideal candidate to examine the consequences of wildlife viewing upon the species. As bear viewing often occurs in sensitive places where bears congregate for mating, rearing young and/or feeding, it is important to evaluate potential positive and negative effects of different viewing practices. Here we reviewed available information on bear viewing practices and their effects on bears, people and ecosystems. Behavioural, physiological and ecological aspects related to bears are reviewed from three different perspectives: ecotourism consequences for bears, direct bear-human interactions and social impacts of bear ecotourism. Because bear viewing can have positive and negative impacts on both bear populations and bear-human interactions, it is important to carefully evaluate every practice associated with bear viewing at a local scale. Because bear populations around the world have diverse population statuses and different management regimes, successful procedures and rules effective in one place do not guarantee that they will be adequate elsewhere. Effective management of bear viewing practices requires a better understanding of the consequences for bears, the mechanisms behind observed bear reactions to humans, and the results of bear habituation. Because inappropriate beat viewing practices can lead to processes such as food conditioning and habituation, which can have serious consequences for both people and bears, regulations on bear ecotourism are urgently needed to minimize unintended consequences of bear viewing practices.

  • 20. Périquet, Stéphanie
    et al.
    Richardson, Peter
    Cameron, Elissa Z.
    Ganswindt, André
    Belton, Lydia
    Loubser, Elize
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Pretoria, South Africa; University of Oviedo, Spain.
    Effects of lions on behaviour and endocrine stress in plains zebras2017Ingår i: Ethology, ISSN 0179-1613, E-ISSN 1439-0310, Vol. 123, nr 9, s. 667-674Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Living under predation risk may alter both behaviour and physiology of potential prey. In extreme cases, such alterations may have serious demographic consequences, and recent studies support that non-lethal effects of predation may have broad ecological consequences. However, behavioural and physiological responses to predation risk may be related to trade-offs associated with resource acquisition and direct predation risk. We validated an enzyme-linked immunoassay (EIA) for non-invasive monitoring of stress in plains zebras (Equus quagga) from faecal material. We used this assay in combination with behavioural data to assess if plains zebras living with and without lions (Panthera leo) in a mountain savannah in southern Africa differed in behaviour and physiology, and if such differences were influenced by seasons with contrasting resource availability. Zebra group sizes did not differ between areas with and without lions, but zebra groups had more juveniles in an area with lions than groups in an area without lions, but only during the wet season. Similarly, we observed differences in individual vigilance, foraging behaviour and stress hormone concentrations, but all these differences were influenced by seasons. Despite these seasonal influences, our study did not suggest that zebras in an area with lions spent a higher proportion of time being vigilant, a lower proportion of time foraging, or had higher stress hormone levels. Our results instead suggest that zebras' responses to lion presence were highly context dependent and the result of complex interactions between resource abundance and cues about predation risk. Because of the obvious ecological and evolutionary ramifications of such findings, we argue that further research is needed to define the spatial and temporal scales over which predators impose indirect effects on their prey.

  • 21. Westbury, Michael
    et al.
    Dalerum, Fredik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Norén, Karin
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Hofreiter, Michael
    Complete mitochondrial genome of a bat-eared fox (Otocyon megalotis), along with phylogenetic considerations2017Ingår i: Mitochondrial DNA Part B: Resources, ISSN 0343-1223, E-ISSN 2014-1130, Vol. 2, nr 1, s. 298-299Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The bat-eared fox, Otocyon megalotis, is the only member of its genus and is thought to occupy a basal position within the dog family. These factors can lead to challenges in complete mitochondrial reconstructions and accurate phylogenetic positioning. Here, we present the first complete mitochondrial genome of the bat-eared fox recovered using shotgun sequencing and iterative mapping to three distantly related species. Phylogenetic analyses placed the bat-eared fox basal in the Canidae family within the clade including true foxes (Vulpes) and the raccoon dog (Nyctereutes) with high support values. This position is in good agreement with previously published results based on short fragments of mitochondrial and nuclear genes, therefore adding more support to the basal positioning of the bat-eared fox within Canidae.

  • 22. Zarzo-Arias, Alejandra
    et al.
    Penteriani, Vincenzo
    del Mar Delgado, María
    Peón Torre, Paloma
    García-González, Ricardo
    Cruz Mateo-Sánchez, María
    Vázquez García, Pablo
    Dalerum, Fredrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Oviedo University, Spain; University of Pretoria, South Africa.
    Identifying potential areas of expansion for the endangered brown bear (Ursus arctos) population in the Cantabrian Mountains (NW Spain)2019Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 14, nr 1, artikel-id e0209972Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many large carnivore populations are expanding into human-modified landscapes and the subsequent increase in coexistence between humans and large carnivores may intensify various types of conflicts. A proactive management approach is critical to successful mitigation of such conflicts. The Cantabrian Mountains in Northern Spain are home to the last remaining native brown bear (Ursus arctos) population of the Iberian Peninsula, which is also amongst the most severely threatened European populations, with an important core group residing in the province of Asturias. There are indications that this small population is demographically expanding its range. The identification of the potential areas of brown bear range expansion is crucial to facilitate proactive conservation and management strategies towards promoting a further recovery of this small and isolated population. Here, we used a presence-only based maximum entropy (MaxEnt) approach to model habitat suitability and identify the areas in the Asturian portion of the Cantabrian Mountains that are likely to be occupied in the future by this endangered brown bear population following its range expansion. We used different spatial scales to identify brown bear range suitability according to different environmental, topographic, climatic and human impact variables. Our models mainly show that: (1) 4977 km(2) are still available as suitable areas for bear range expansion, which represents nearly half of the territory of Asturias; (2) most of the suitable areas in the western part of the province are already occupied (77% of identified areas, 2820 km(2)), 41.4% of them occurring inside protected areas, which leaves relatively limited good areas for further expansion in this part of the province, although there might be more suitable areas in surrounding provinces; and (3) in the eastern sector of the Asturian Cantabrian Mountains, 62% (2155 km(2)) of the land was classified as suitable, and this part of the province hosts 44.3% of the total area identified as suitable areas for range expansion. Our results further highlight the importance of increasing: (a) the connectivity between the currently occupied western part of Asturias and the areas of potential range expansion in the eastern parts of the province; and (b) the protection of the eastern sector of the Cantabrian Mountains, where most of the future population expansion may be expected.

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