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  • 1.
    Alm Bergvall, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Development of feeding selectivity and behavioural syndromes in fallow deer2007Inngår i: Book of abstracts of the International Union of Game Biologists XXVIII Congress., 2007, s. 106-Konferansepaper (Fagfellevurdert)
  • 2.
    Alm Bergvall, Ulrika
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Svensson, Lisa
    Kjellander, Petter
    Vigilance adjustments in relation to long- and short term risk in wild fallow deer (Dama dama)2016Inngår i: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 128, s. 58-63Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The risk allocation hypothesis predicts that vigilance should be adjusted to the temporal variation in risk. We test this hypothesis in wild fallow deer exposed to short term (disturbance) and long term (presence of a fawn after parturition) changes in risk. We recorded the proportion, frequency and type of vigilance and size of used area before and after parturition, in GPS-collared wild female fallow deer. Vigilance was divided in two main groups: non-grazing vigilance and grazing vigilance. The latter group was divided into grazing vigilance while chewing and a grazing vigilance when chewing was interrupted. By recording external disturbance in form of passing cars, we were able to investigate if this altered the amount, and type of vigilance. We found that females increased the proportion and frequency of grazing vigilance stop chewing after parturition. The grazing vigilance chewing was unaffected, but non-grazing vigilance decreased. Disturbance increased the proportion grazing vigilance stop chewing to the same extent before and after parturition. We found a clear decrease in female home range size after parturition as a possible behavioural adjustment. The increase in grazing vigilance stop chewing after parturition is a rarely described but expected cost of reproduction.

  • 3.
    Alm, Ulrika
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    The effect of food quality and relative abundance on food choice in fallow deer2002Inngår i: Animal Behaviour, Vol. 64, s. 439-445Artikkel i tidsskrift (Fagfellevurdert)
  • 4.
    Andersson, Anastasia
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Laikre, Linda
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Two shades of boldness: novel object and anti-predator behavior reflect different personality dimensions in domestic rabbits2014Inngår i: Journal of ethology, ISSN 0289-0771, E-ISSN 1439-5444, Vol. 32, nr 3, s. 123-136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It is increasingly common to quantify and describe behavioral variation in domestic and wild animals in terms of personality. Correlating behavioral traits are referred to as personality dimensions or factors and different dimensions have been reported in different species. Boldness is a well-described personality dimension in several species, although some issues remain unclear. Previous models of boldness include both novelty and risk taking, but recent studies indicate that these types of behaviors may reflect separate personality dimensions. In this study, we developed a behavioral test battery for domestic rabbits, and recorded behaviors of 61 individuals in four different situations (novel object, novel arena, social, and predator interactions). We used domestic rabbits as a model because behavioral variation in rabbits has rarely been quantified in terms of personality dimensions, although rabbit behavior is described. We also wanted to investigate behavioral variation in a Swedish rabbit breed of conservation concern - the Gotland rabbit. Factor analysis of the behavioral test measures suggested three personality dimensions: exploration, boldness, and anxiety. Novel object scores clustered in the exploration and boldness factors, whereas scores associated with predator interactions were explained by anxiety, indicating that novel object and anti-predator behavior reflect different personality dimensions in rabbits.

  • 5. Andersson, Martin O.
    et al.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Chirico, Jan
    Christensson, Madeleine
    Lindgren, Per-Eric
    Nordström, Jonas
    Kjellander, Petter
    Molecular detection of Babesia capreoli and Babesia venatorum in wild Swedish roe deer, Capreolus capreolus2016Inngår i: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 9, artikkel-id 221Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: The epidemiology of the zoonotic tick-transmitted parasite Babesia spp. and its occurrence in wild reservoir hosts in Sweden is unclear. In European deer, several parasite species, including Babesia capreoli and the zoonotic B. venatorum and B. divergens has been reported previously. The European roe deer, Capreolus capreolus, is an important and common part of the indigenous fauna in Europe, as well as an important host for Ixodes ricinus ticks, the vector of several Babesia spp. in Europe. Here, we aimed to investigate the occurrence of Babesia spp. in roe deer in Sweden. Findings: Roe deer (n = 77) were caught and sampled for blood. Babesia spp. was detected with a PCR assay targeting the 18S rRNA gene. The prevalence of Babesia spp. was 52 %, and two species were detected; B. capreoli and B. venatorum in 44 and 7.8 % of the individuals, respectively. Infection occurred both in summer and winter. Conclusions: We showed that roe deer in Sweden, close to the edge of their northern inland distributional range, are infected with Babesia spp. The occurrence of B. venatorum in roe deer imply that it is established in Sweden and the zoonotic implication of this finding should be regarded to a greater extent in future.

  • 6.
    Bergvall, Ulrika A
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Development of feeding selectivity and consistency in food choice over5 years in fallow deer2009Inngår i: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 80, s. 140-146Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to better understand the development and maintenance of feeding selectivity, several feedingexperimentswere performed with fallowdeer (Damadama L.). In experiments performed when the fawnswere between tenand 27 days old, itwas found that all fawnsshowedpreferences for sucrose but aversionstowards tannic acid and ascorbic acid.However, differences in selectivity towards tannic acidwere presentalready before the fawns became functional ruminants and these individual differences lasted 5 years.Moreover, individuals that ingested overall less tannic acid, searched more thoroughly between foodsources. When the foraging behaviour was compared with age (11–41 days old and 65–97 days old), itwas found that the time a fawn spent eating, increased with age, and the time spent on exploration,smelling and tasting plants decreased with age. Furthermore, the fawns increased their intake of grassand herbs, while the intake of soil and dead plant material decreased with age.

  • 7.
    Bergvall, Ulrika A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Co, Michelle
    Bergström, Roger
    Sjöberg, Per J. R.
    Waldebäck, Monica
    Turner, Charlotta
    Anti-browsing effects of birch bark extract on fallow deer2013Inngår i: European Journal of Forest Research, ISSN 1612-4669, E-ISSN 1612-4677, Vol. 132, nr 5-6, s. 717-725Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A major problem within forest industry is unwanted browsing on seedlings from mammalian herbivores. The aim of this study was to evaluate the effects of birch bark extracts as repellents towards fallow deer. Birch bark was extracted in a conventional way with ethanol as solvent at ambient temperature and with a new method, liquid CO2 extraction. An analysis of the ethanol-extracted birch bark showed that it contained large amounts of terpenoids, of which the most abundant was betulin. In seven different treatment trials, we used 15 individually handled fallow deer. To investigate the binary taste preferences, birch bark extract was added to food and presented in two bowls in typical two-choice tests. We found that the amount of a food type consumed during a trial and the number of shifts between food bowls were dependent on the amount of the birch extract the food contained. Concentrations of above 1 % by dry weight of birch extract acted as a repellent. In addition, such concentrations produced shorter feeding bouts by a greater willingness to change bowls. Therefore, our conclusion is that birch bark extract acts as a repellent towards fallow deer and is therefore likely to act as a repellent against other deer species. In addition, we show that birch bark extract produced by the new and more environmentally sustainable method employing liquid CO2 mixed with ethanol has the same repellent effect as the traditional ethanol extraction.

  • 8.
    Bergvall, Ulrika A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Jäderberg, Lars
    Kjellander, Petter
    The use of box-traps for wild roe deer: behaviour, injuries and recaptures2017Inngår i: European Journal of Wildlife Research, ISSN 1612-4642, E-ISSN 1439-0574, Vol. 63, nr 4, artikkel-id 67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tracking devices are commonly used to locate and monitor wild animals for studying spatial ecology and survival rates. There is growing interest in capture effects, partially to minimize the impact on the study species, but also for animal welfare reasons. This study aims to examine roe deer behaviour in box-traps, when restrained, when released and during recaptures to quantify injuries and deaths over a period of 41 years. We use data from 2911 captures from 926 individuals between 1973 and 2014. We recorded behaviour inside the box-traps over two seasons. We also recorded behavioural data from 671 catches of 346 individuals during six seasons to study habituation. Additionally, we discuss box-traps in relation to ethological theory and animal welfare. Over a 41-year period, one roe deer suffering from starvation was found dead in a trap (0.035%), which cannot be solely related to capture (N = 926). About 58% of all roe deer were recaptured at least once during their life time. There was a low prevalence of injuries (0.5% of the captures, N = 2911), and they occurred predominately to the nose or antlers in velvet (in males). During the first hour after capture, animals typically stand very tense between eating bouts. Thereafter, the deer tended to move more softly and exhibited resting behaviours (e.g. lying down). Overall, we conclude that this method of capture and handling had very low impact on the welfare or survival of roe deer, which also habituated to recapture over successive events.

  • 9.
    Bergvall, Ulrika A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Kjellander, Petter
    Ahlqvist, Per
    Johansson, Örjan
    Sköld, Kent
    Arnemo, Jon M.
    Chemical Immobilization of Free-ranging Fallow Deer (Dama dama): Effect of Needle Length on Induction Time2015Inngår i: Journal of Wildlife Diseases, ISSN 0090-3558, E-ISSN 1943-3700, Vol. 51, nr 2, s. 484-487Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We evaluated impact of the needle length, sex, and body condition on chemical immobilization induction time in 50 (29 males and 21 females) free-ranging fallow deer (Dama dama) in Sweden, 2006-11. Induction time is probably the single most important factor when immobilizing free-ranging wildlife with the use of a remote drug-delivery system. Induction times should be short to minimize stress and risk of injury, and to ensure that immobilized animals can be found and clinically monitored as soon as possible. We measured the distance between the darting location and where we recovered the immobilized animal and also the time occurring between the two events. We used two types of needles: 2.0 × 30- or 2.0 × 40-mm barbed needles with side ports. The most important result is that a 10-mm-longer dart needle can reduce the retrieval time substantially (>20 min) until an animal is under monitoring. On average after the darting, the retrieval time decreased from 51 to 29 min and the distance decreased from 519 m from the darting location to 294 m. We suggest that a needle length of 40 mm is preferable for immobilization of wild fallow deer, especially for animals in over-average-to-fat body condition.

  • 10.
    Bergvall, Ulrika A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Directional associational plant defense from Red deer (Cervus elaphus) foraging decisions2017Inngår i: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 8, nr 3, artikkel-id e01714Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concept of associational plant defenses is widely accepted and implies that an unpalatable plant can protect its neighbors from grazing. We have investigated the new but similar question of whether a part of a plant, for example, the top or bottom, can protect other parts. At the same time, we investigated whether the previously observed selection of the apical shoot and upper leaves of plants is a direct consequence of food quality (the plant vigor hypothesis) or whether there is an innate or learnt foraging pattern behind the observation. In experiments, we used 1 m high artificial trees, made from aspen branches, and measured red deer browsing from the top (above 0.5 m) and bottom (below 0.5 m), with application of condensed tannin to the top or bottom as a proxy for plant part unpalatability. There were four treatments where either none, both, or one part (top or bottom) of the artificial trees had tannin applied. As expected, we found that red deer consumed less from parts with tannin. We also found that a defended top protected an undefended bottom, but we found no evidence for the opposite relationship, which could be explained by foraging behavior. When examining the behavior, we found that adult red deer prefer to start feeding from the top of a plant. We also found that they spent a shorter time feeding on a defended top. This behavior might cause a defended top to protect an undefended bottom. Such directional associational plant defense could be the result of selectivity with limited flexibility and might be more pronounced for mammalian herbivores than for insects, since mammals are bigger in size and more restricted in their head position. An important applied aspect of these results is that when saplings are protected by adding a repellent, for instance in forestry, it might be enough to apply repellent to the tops. On the other hand, according to this directional associational plant defense, protected bottoms will not protect tops, so newly grown apical shoots may need new protection.

  • 11.
    Bergvall, Ulrika A
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Rautio, Pasi
    Kesti, Kari
    Tuomi, Juha
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Associational effects of plant defences in relation to within- and between-patch food choice by a mammalian herbivore: neighbour contrast susceptibility and defence.2006Inngår i: Oecologia, ISSN 0029-8549, Vol. 147, nr 2, s. 253-60Artikkel i tidsskrift (Fagfellevurdert)
  • 12.
    Bergvall, Ulrika A
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rautio, Pasi
    Luotola, Tuomas
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    A test of simultaneous and successive negative contrast in fallow deer foraging behaviour2007Inngår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 74, nr 3, s. 395-402Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The study of contrast investigates how rewards influence behaviour when animals are exposed to two or more levels of rewards compared to when they experience only a single level. The appearance of an exaggerated response to a shift in reward is referred to as a contrast effect and is an empirically well-established phenomenon. Although contrast effects could be important in foraging behaviour, no direct experimental tests of contrast effects in foraging by mammalian herbivores exist. During foraging, mammalian herbivores can encounter a range of plants that vary in the amount of nutrients and toxins. They may thus compare food items by taste, which in turn can give rise to contrast effects. In feeding experiments with fallow deer, Dama dama, we investigated the presence of simultaneous negative contrast. We found that the deer consumed less from a bowl of pellets containing 1% tannin when they shifted to it from a bowl with pellets containing only 0.25% tannin than when they shifted from another bowl with pellets containing 1% tannin. We estimated a fourfold difference between treatments in test food consumption at the highest levels of preloading, but none at the lowest levels. We found no support for successive negative contrast in experiments where the deer approached food in a runway, comparing a current reward with the memory of a previous reward. We suggest that simultaneous negative contrast can influence foraging decisions in mammalian herbivores.

  • 13.
    Bergvall, Ulrika A
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rautio, Pasi
    Siren, Hanna
    Tuomi, Juha
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    The effect of spatial scale on plant associational defences against mammalian herbivores2008Inngår i: Ecoscience, Vol. 15, s. 343-348Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Intraspecific variation in plant toxins at different spatial scales can influence foraging decisions by wild herbivores. In order to investigate plant associational defences in relation to spatial scale, we performed an experiment with fallow deer encountering 2 patches of low- and high-tannin hazel branches. One patch was good, consisting of 7 low- and I high-tannin branch, and the other bad, with low- and 7 high-tannin branches. We kept the between-patch spatial scale constant and varied the within-patch spatial scale: the branches in a patch were either spread out or close together in a bundle. When the low-tannin branches were spread out, the deer showed a clear preference for low_tannin branches both patches and consumed similar amounts from low-tannin branches in the good and the bad patch, which means that there was no associational defence. In contrast, when the branches instead were together in a bundle, within-patch selectivity decreased and between-patch selectivity increased, and the low-tannin branches in the bad patch were less eaten than the low-tannin branches in the good patch, which corresponds to associational defence. We conclude that small inter-plant distances can be crucial for the operation of plant associational defences

  • 14.
    Bergvall, Ulrika A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi. University of Edinburgh, U.K..
    Schäpers, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Kjellander, Petter
    Weiss, Alexander
    Personality and foraging decisions in fallow deer, Dama dama2011Inngår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 81, nr 1, s. 101-112Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recent studies have examined the ecological and evolutionary bases for variation in animal personality. However, only a few such studies have examined how foraging parameters are influenced by different personality domains. In wild ungulates, the trade-off between the time spent on food intake and antipredator behaviour differs between individuals, but the underlying reason for this is not yet well understood. One possibility is that this trade-off reflects personality dimensions such as boldness. To relate foraging decisions to personality we measured personality and performed feeding experiments with familiar and novel food in familiar and novel situations. We measured personality traits in 15 tame fallow deer, using novel object tests (NO), behavioural observations (BO) and personality ratings (PR). Boldness dimensions were found using PR and NO, dominance dimensions were found using BO and PR, and a flexibility dimension was found using BO. Multitrait–multimethod analysis showed that similar dimensions were significantly correlated across different methods and that different dimensions were not significantly correlated, even if measured using the same method. We also found that novel food eaten in familiar situations and familiar food eaten in novel situations were strongly related to boldness but not dominance, flexibility or age. Thus the trade-off between the benefits of gaining more food and the costs of reduced vigilance or increased toxin ingestion reflect boldness. These findings highlight the nature of personality dimensions in ungulates and how boldness impacts foraging behaviour.

  • 15.
    Bergvall, Ulrika Alm
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Balogh, Alexandra C.V.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Consummatory simultaneous positive and negative contrast in fallow deer: implications for selectivity2009Inngår i: Mammalian Biology, ISSN 1616-5047, E-ISSN 1618-1476, Vol. 74, nr 3, s. 236-239Artikkel i tidsskrift (Fagfellevurdert)
  • 16.
    Bergvall, Ulrika Alm
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Plant secondary compounds and the frequency of food types affect food choice by mammalian herbivores2005Inngår i: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 86, nr 9, s. 2450-2460Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have investigated food choice in individual fallow deer (Dama dama) encountering different relative frequencies of food types in the form of bowls containing pellets with either high or low concentrations of hydrolyzable tannin. We performed two similar experiments, one with large and one with small differences in tannic acid concentration. With small differences in tannic acid concentration, the ratio of the consumption per low- and high-tannin bowl was independent of frequency of occurrence, but with large differences in tannic acid concentration, we found frequency-dependent food choice. The deer ate proportionally less from high-tannin bowls if these occurred at low relative frequency. Variation between frequency treatments in the average order of encounter of bowl types might have produced this effect, because we found that the deer left a high-tannin bowl more quickly if they had switched to it from a low-tannin bowl. We argue that the perceived contrast between the tastes of different food types can play a role for food choice by mammalian herbivores.

  • 17.
    Birgersson, Björn
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Alm, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Forkman, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Colour vision in fallow deer: a behavioural study2001Inngår i: Animal Behaviour, Vol. 61, s. 367-371Artikkel i tidsskrift (Fagfellevurdert)
  • 18. Bonnot, Nadège C.
    et al.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Jarnemo, Anders
    Kjellander, Petter
    Who's afraid of the big bad wolf? Variation in the stress response among personalities and populations in a large wild herbivore2018Inngår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 188, nr 1, s. 85-95Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Faced with rapid environmental changes, individuals may express different magnitude and plasticity in their response to a given stressor. However, little is known about the causes of variation in phenotypic plasticity of the stress response in wild populations. In the present study, we repeatedly captured individual roe deer (Capreolus capreolus) from two wild populations in Sweden exposed to differing levels of predation pressure and measured plasma concentrations of stress-induced cortisol and behavioral docility. While controlling for the marked effects of habituation, we found clear between-population differences in the stress-induced cortisol response. Roe deer living in the area that was recently recolonized by lynx (Lynx lynx) and wolves (Canis lupus) expressed cortisol levels that were around 30% higher than roe deer in the human-dominated landscape free of large carnivores. In addition, for the first time to our knowledge, we investigated the stress-induced cortisol response in free-ranging newborn fawns and found no evidence for hypo-responsiveness during early life in this species. Indeed, stress-induced cortisol levels were of similar magnitude and differed between populations to a similar extent in both neonates and adults. Finally, at an individual level, we found that both cortisol and docility levels were strongly repeatable, and weakly negatively inter-correlated, suggesting that individuals differed consistently in how they respond to a stressor, and supporting the existence of a stress-management syndrome in roe deer.

  • 19. Borg, O.
    et al.
    Wille, M.
    Kjellander, P.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Lindgren, P.-E.
    Chirico, J.
    Lundkvist, Å.
    Expansion of spatial and host range of Puumala virus in Sweden: an increasing threat for humans?2017Inngår i: Epidemiology and Infection, ISSN 0950-2688, E-ISSN 1469-4409, Vol. 145, nr 8, s. 1642-1648Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hantaviruses are globally distributed and cause severe human disease. Puumala hantavirus (PUUV) is the most common species in Northern Europe, and the only hantavirus confirmed to circulate in Sweden, restricted to the northern regions of the country. In this study, we aimed to further add to the natural ecology of PUUV in Sweden by investigating prevalence, and spatial and host species infection patterns. Specifically, we wanted to ascertain whether PUUV was present in the natural reservoir, the bank vole (Myodes glareolus) further south than Dalälven river, in south-central Sweden, and whether PUUV can be detected in other rodent species in addition to the natural reservoir. In total, 559 animals were collected at Grimsö (59°43'N; 15°28'E), Sala (59°55'N; 16°36'E) and Bogesund (59°24'N; 18°14'E) in south-central Sweden between May 2013 and November 2014. PUUV ELISA-reactive antibodies were found both in 2013 (22/295) and in 2014 (18/264), and nine samples were confirmed as PUUV-specific by focus reduction neutralization test. Most of the PUUV-specific samples were from the natural host, the bank vole, but also from other rodent hosts, indicating viral spill-over. Finally, we showed that PUUV is present in more highly populated central Sweden.

  • 20. Debeffe, L.
    et al.
    Lemaitre, J. F.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Science, Sweden.
    Hewison, A. J. M.
    Gaillard, J. M.
    Morellet, N.
    Goulard, M.
    Monestier, C.
    David, M.
    Verheyden-Tixier, H.
    Jäderberg, L.
    Vanpe, C.
    Kjellander, P.
    Short- and long-term repeatability of docility in the roe deer: sex and age matter2015Inngår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 109, s. 53-63Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Behavioural consistency is a key assumption when evaluating how between-individual differences in behaviour influence life history tactics. Hence, understanding how and why variation in behavioural repeatability occurs is crucial. While analyses of behavioural repeatability are common, few studies of wild populations have investigated variation in repeatability in relation to individual status (e.g. sex, age, condition) and over different timescales. Here, we aimed to fill this gap by assessing within-population variation in the repeatability of docility, as assessed by the individual’s response to human handling, in a free-ranging population of European roe deer, Capreolus capreolus. Docility was an equally repeatable behaviour at both short- and long-term timescales, suggesting that this behavioural trait is stable across time. Repeatability did not differ markedly between age and sex categories but tended to be higher in juvenile males than in juvenile females. Finally, contrary to expectation, individual variation in the repeatability of docility was not correlated with individual body mass. Further studies are required to assess the life history consequences of the individual variation in docility we report here.

  • 21.
    Haage, Marianne
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Bergvall, Ulrika A.
    Maran, Tiit
    Kiik, Kairi
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Situation and context impacts the expression of personality: The influence of breeding season and test context2013Inngår i: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 100, s. 103-109Artikkel i tidsskrift (Fagfellevurdert)
  • 22.
    Haage, Marianne
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Maran, Tiit
    Alm Bergvall, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Elmhagen, Bodil
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Evolutionary maintenance of personality – a field experiment on survival and personalityInngår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939Artikkel i tidsskrift (Fagfellevurdert)
  • 23.
    Haage, Marianne
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Maran, Tiit
    Alm Bergvall, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Elmhagen, Bodil
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Angerbjörn, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    The influence of spatiotemporal conditions and personality on survival in reintroductions-evolutionary implications2017Inngår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 183, nr 1, s. 45-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Personality exists in non-human animals and can impact fitness. There is, however, a shortage of empirical studies in certain areas within the field, and fundamental evolutionary theory on personality remains largely untested. For example, little is known on how variation in personality is maintained over evolutionary time. Theory suggests that fluctuating selection pressures due to spatiotemporal variation in conditions, e.g. food availability, is a possible mechanism and a few studies have shown that the success of different personality types varies with spatiotemporal conditions. However, it remains unknown whether different mechanisms can maintain personality within a species. Here we use a reintroduction programme for the critically endangered European mink (Mustela lutreola) to test whether multiple personality trait domains (boldness, exploration and sociability) affected survival in two different years and islands. This was done through pre-release personality tests and post-release radio-tracking monitoring. Survival was positively correlated with boldness, whereas the relationship with exploration was either negative or positive depending on year/island. The results show a complex relationship between personality and survival and suggest that exploration can be maintained over evolutionary time via spatiotemporal variation in conditions. However, in contrast to exploration, boldness did not vary spatiotemporally and sociability had no impact on survival. This indicates that different personality trait domains might be maintained by different mechanisms. To date, personality has been studied primarily within behavioural sciences, but through empirical findings we highlight the importance of personality also in ecology and conservation biology.

  • 24. Huber, Nikolaus
    et al.
    Vetter, Sebastian G.
    Evans, Alina L.
    Kjellander, Petter
    Küker, Susanne
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish University of Agricultural Sciences, Sweden.
    Arnemo, Jon M.
    Quantifying capture stress in free ranging European roe deer (Capreolus capreolus)2017Inngår i: BMC Veterinary Research, ISSN 1746-6148, E-ISSN 1746-6148, Vol. 13, artikkel-id 127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background

    To understand and reduce the concomitant effects of trapping and handling procedures in wildlife species, it is essential to measure their physiological impact. Here, we examined individual variation in stress levels in non-anesthetized European roe deer (Capreolus capreolus), which were captured in box traps and physically restrained for tagging, biometrics and bio-sampling. In winter 2013, we collected venous blood samples from 28 individuals during 28 capture events and evaluated standard measurements for stress (heart rate, body temperature, neutrophil to lymphocyte ratio, lactate and total cortisol). Additionally, we assessed stress using the immunological tool, Leukocyte Coping Capacity (LCC), a real-time proxy for stress measuring oxygen radical production by leukocytes. Finally, the behavioral response to handling was recorded using a scoring system.

    Results

    LCC and therefore stress levels were negatively influenced by the time animals spent in the box trap with human presence at the capture site prior to handling. In contrast, none of the classical stress measures, including total cortisol, nor the behavioral assessment, were correlated with the stressor tested (time of human presence prior to handling) and thus did not provide a clear depiction regarding the extent of the animals short-term stress response.

    Conclusions

    Overall our study verifies the LCC as a strong method to quantify short-term stress reactions in wildlife. Moreover, our results clearly show that human presence at the trapping site prior to handling should be kept to an absolute minimum in order to reduce stress levels.

  • 25.
    Kjellander, Petter
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Svartholm, Ida
    Swedish University of Agricultural Sciences, Sweden.
    Bergvall, Ulrika A
    University of Edinburgh, UK; Swedish University of Agricultural Sciences, Sweden.
    Jarnemo, Anders
    Swedish University of Agricultural Sciences, Sweden.
    Habitat use, bed-site selection and mortality rate in neonate fallow deer Dama dama2012Inngår i: Wildlife Biology, ISSN 0909-6396, E-ISSN 1903-220X, Vol. 18, nr 3, s. 280-291Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An understanding of mortality patterns, and especially the variation in juvenile mortality, is an important component in vertebrate population dynamics. Our study investigates, for the first time, neonate mortality and two levels of spatial behaviour, in a free-ranging fallow deer Dama dama population in southwestern Sweden. In the summers of 2008 and 2009, 36 fawns were marked with radio-collars. Neonate mortality calculated by the Kaplan-Meier method was 23.6%. Mortality caused by predation was low, since only one of eight non-surviving fawns died from predation, probably by red fox Vulpes vulpes. The spatial behaviour of the neonates was examined by habitat selection at home-range level, which in fact is a selection made by the mother, and at bed-site level within that habitat. Compositional analysis revealed a significant preference for arable land, pasture and coniferous forest between 5-15 m high, compared to young forest. Selected bed sites showed significantly lower visibility and higher amount of canopy cover than random sites. Surprisingly, we did not find any relationship between canopy cover and visibility in selected bed sites while it showed a significant and negative relationship at random bed sites. We interpret this finding as while high canopy cover and low visibility covary at the habitat level, fawns seem to select these two bed-site variables independently, perhaps for thermoregulatory reasons. Since there are few predators in our study area and predation pressure is low, this behaviour is not connected to actual survival rates in this area, but would rather be in support of the hypothesis of ‘pleiotropy’ as thermoregulatory reasons for bed-site selection in neonate fawns might be the most important contemporary selection force in the absence of large predators.

  • 26. Küker, Susanne
    et al.
    Huber, Nikolaus
    Evans, Alina
    Kjellander, Petter
    Bergvall, Ulrika A
    Department of Ecology, Swedish University of Agricultural Sciences, Grimsö Wildlife Research Station, Riddarhyttan, Sweden.
    Jones, Krista L
    Arnemo, Jon M
    Hematology, serum chemistry, and serum protein electrophoresis ranges for free-ranging roe deer (Capreolus capreolus) in Sweden.2015Inngår i: Journal of Wildlife Diseases, ISSN 0090-3558, E-ISSN 1943-3700, Vol. 51, nr 1, s. 269-73Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present the first reference ranges for hematology (n = 35 animals), serum biochemistry (n = 62), and serum protein electrophoresis (n = 32) in physically restrained free-ranging roe deer (Capreolus capreolus). Animals were captured in box traps and physically restrained for blood sampling during the winter in Sweden, 2011-13. No clinically significant sex or age differences were found.

  • 27. Rautio, Pasi
    et al.
    Alm Bergvall, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Karonen, Maarit
    Salminen, Juha-Pekka
    Bitter problems in ecological feeding experiments: commercial tannin preparations and common methods for tannin quantifications2007Inngår i: Biochemical systematics and ecology, ISSN 0305-1978, Vol. 35, nr 5, s. 257-262Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [sv]

    In the field of plant-herbivore interactions research methods manipulating plant secondary metabolites are becoming more and more popular. In most cases food offered to herbivores is manipulated with commercially available compounds, or more specifically, compound mixtures. Among the most commonly used is tannic acid, the almost sole commercial source of hydrolysable tannins. However, recent studies have shown that different tannic acid preparations are not comparable in their tannin structures. While tannic acids are meant to contain only gallotannins (GTs), some commercial preparations compose mainly of more simple galloglucoses (that have e.g. much lower protein precipitation capacity than GTs) or even of gallic acid (the hydrolysis product of GTs). Another commonly used group of tannins used in feeding trials is condensed tannins (CTs), usually in the form of quebracho tannin. One of the problems in using quebracho is that it contains different CT structures than e.g. leaves of many deciduous trees. Additionally, when analysed with the common acid-butanol assay for total CTs, quebracho tannins give even 30-fold lower absorbance than the CTs of those deciduous trees. This dilemma is highlighted by the fact that quebracho tannin is commonly used as a standard when analysing CT concentrations in plant tissues. In addition to above problems, different herbivore species are known to react differently to varying tannin structures. Therefore, ecologically the most serious concern lies in that our commercial tannin compounds might have biological activities highly different from the tannins of our study plants. Below we discuss these problems, as well as some means to deal with them.

  • 28. Rautio, Pasi
    et al.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Tuomi, Juha
    Kesti, Kari
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Food selection by herbivores and neighbourhood effects in the evolution of plant defences2012Inngår i: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 49, nr 1-2, s. 45-57Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A number of studies have reported how neighbouring plants may influence herbivory on palatable or unpalatable plants. Such neighbourhood effects can have important evolutionary consequences as they may either promote the evolutionary stability of plant defences or, alternatively, select against the fixation of plant defences and instead promote a stable polymorphism of palatable and unpalatable plants. These consequences depend on whether the difference in herbivore damage between unpalatable and palatable plants is smaller or, alternatively, greater when the neighbours are unpalatable instead of palatable. Such relations can arise when the neighbourhood effects are non-parallel among palatable and unpalatable plants. We outline two basic situations of non-parallel neighbourhood effects and illustrate how they can come about. A detailed dissection of these interactions reveals that there are several qualitatively distinct mechanisms that promote either evolutionary stability of plant defences or alternatively polymorphism. Our classification of mechanisms can be used to clarify and explain observations obtained in the field of plant herbivore interactions and predator prey interactions, both at the population and the community level.

  • 29. Rautio, Pasi
    et al.
    Kesti, Kari
    Alm Bergvall, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Tuomi, Juha
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Etologi.
    Spatial scales of foraging in fallow deer: Implications for associational effects in plant defences2008Inngår i: Acta Oecologica, Vol. 34Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Large herbivores select food at several spatial scales: plant communities are chosen at a landscape scale, plant patches are chosen within a plant community, and individual plants within a patch. Foraging decision at the patch level can result in associational effects in plant communities and populations. Several studies have shown that herbivore attack and consumption rates may not only depend on a plant's own defence traits, but also on the defence traits of its neighbours. In the present experiment we investigated whether the spatial scale of the food distribution affects food selection by fallow deer and whether the foraging behaviour gives rise to associational effects in plant defences. In a population of captured wild fallow deer we simulated a natural situation where two separate plant patches are exposed to intense herbivory pressure. We presented different spatial arrangements of low- and high-tannin food to the deer, varying the frequency of the feeder types within and between patches. We found that the deer consumed palatable food among the unpalatable food on average as much as they consumed palatable food among other palatable feeders. However, when unpalatable food occurred among the palatable food it was more consumed than among other unpalatable feeders. Hence, we did not find support for associational defence, but our results supported associational susceptibility. At the between patch level a patch of mainly high-tannin feeders was consumed less when presented near to a patch of mainly low-tannin feeders, suggesting that for well-defended plants having palatable neighbours in a nearby patch might accentuate the effectiveness of their defence.

  • 30.
    Stutz, Rebecca S.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Tuomi, Juha
    Rautio, Pasi
    Cohesiveness reduces foraging efficiency in a social herbivore2018Inngår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 135, s. 57-68Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    For social foragers, movement as a group could increase foraging efficiency through collective discovery of high-quality food sources. This would require an efficient mechanism for transferring information about food quality between individuals. Conversely, the constraints of foraging as a cohesive group could decrease efficiency; grouping may persist to serve other functions such as protection from predators. To test what drives cohesion in herbivores, we manipulated patch shape and within-patch pattern of food quality and quantified the effects on group level diet selection by a social herbivore, the fallow deer, Dama dama. We arranged feeders containing fodder in lines or blocks, and manipulated the pattern of food quality within patches by adding tannin, a plant secondary compound that decreases palatability. We quantified the relative consumption of low- and high-tannin food to compare diet selectivity at the group level between patch treatments. If group foraging evolved to increase foraging efficiency, altering the spatial arrangement of food should not affect diet selectivity because information about food location and quality is shared. We found, however, that the herd expressed different levels of selectivity between both patch shapes and food quality patterns. Deer selected better diets in blocks than lines. In lines, the herd selected better diets when quality varied between alternate feeders rather than between the two halves of the patch, suggesting a reliance on personal rather than group information. Deer consumed the most at patch centres in all treatments except in blocks with high-tannin centres, but diet selection was poorer in the latter compared to blocks with low-tannin centres. Aggregation at the centre of patches appears to have restricted exploitation of the best food. Predation pressure and/or resource variability may have favoured the evolution of a foraging strategy that prioritizes social cohesion over effective diet selection.

  • 31.
    Stutz, Rebecca S.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Croak, Benjamin M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Leimar, Olof
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Bergvall, Ulrika A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Borrowed plant defences: Deterring browsers using a forestry by-product2017Inngår i: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 390, s. 1-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mammalian browsers can cause ecologically and economically significant damage to important tree species, particularly at the vulnerable seedling stage. Some tree species or particular parts of trees are less preferred as a result of chemical defences - harnessing such defences could reduce the appeal of more preferred trees and thus their loss to browsing. We tested the potential of birch bark extract, a forestry by-product, to protect seedlings of Scots pine Pinus sylvestris from two globally significant browsers: moose Alces alces and red deer Cervus elaphus. We quantified the responses by captive animals to extract application as a function of both the distance between seedlings and whether the extract was applied to all or alternate seedlings. Both moose and red deer consumed pine seedlings less frequently when seedlings were treated with birch bark extract, but their responses differed when only alternate seedlings were treated. At inter-seedling distances equivalent to those used in forestry, red deer browsed untreated seedlings more frequently when alternate seedlings were treated than when none were treated (associational susceptibility), whereas moose browsed untreated seedlings less frequently with treated than untreated neighbours (associational refuge). These neighbourhood effects were not evident at inter-seedling distances three times larger or smaller than those used in forestry. There was also no significant difference in the frequency of browsing on treated seedlings in alternate compared to completely treated arrangements at any inter-seedling distance. Red deer removed significantly less foliage from treated than untreated seedlings once browsed. Browsing by moose followed a similar but non-significant trend. The relative number of untreated to treated seedlings browsed was 2:1 for red deer and 4:1 for moose. Red deer used a finer scale of selection than moose for choosing between seedlings, consistent with their smaller body mass. However, the coarser-scale of selection used by moose resulted in consumption of more untreated relative to treated seedlings. Our study highlights the potential of existing plant defensive chemistry, harvested from forestry by-products, to reduce herbivore damage to tree seedlings. We also demonstrate the need to consider both plant associational effects and the foraging strategies of the dominant herbivores in applying repellents.

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