Profiles

Ulrika Alm Bergvall

Ulrika Alm Bergvall

Forskare, Docent

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Arbetar vid Zoologiska institutionen
Telefon 08-16 41 33
E-post ulrika.alm-bergvall@zoologi.su.se
Besöksadress Svante Arrheniusväg 18 B
Rum D 512a
Postadress Zoologiska institutionen: Etologi 106 91 Stockholm

Om mig

The interactions between plants and herbivores are among the most important and intriguing in nature and the scientific field of plant-herbivore interactions is rapidly developing. In my current FORMAS funded project I investigate foraging psychology and small to medium scale foraging decisions in fallow deer (Dama dama), red deer (Cervus elaphus) and moose (Alces alces).

I spent my VR financed postdoc time at the Department of Psychology at the University of Edinburgh, and after that I spent some years at Grimsö Wildlife research station, Swedish University of Agricultural Sciences (SLU). I have been involved in animal personality research in Fallow deer, Rabbit, European Mink and Roe deer. At the moment I’m also involved in a large project (RåFäst, P. Kjellander, Grimsö) about roe deer, ticks, rodents and tick-borne diseases including people from several disciplines from Linköping, SVA, Public Health Agency of Sweden, among others. I’m also a member of the EURODEER group (http://www.eurodeer.org/), collaborating with European Roe deer researchers. I also work for Grimsö, SLU, as a coordinator for The Swedish Environmental protection Agency with testing new traps for wildlife. I teach at several courses in Ethology (basic to master level) at Stockholm University just because it is fun.

 

 

Publikationer

I urval från Stockholms universitets publikationsdatabas
  • 2018. Rebecca S. Stutz (et al.). Animal Behaviour 135, 57-68

    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.

  • 2018. Nadège C. Bonnot (et al.). Oecologia

    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.

  • 2017. Ulrika A. Bergvall, Olof Leimar. Ecosphere 8 (3)

    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.

  • 2017. Ulrika A. Bergvall, Lars Jäderberg, Petter Kjellander. European Journal of Wildlife Research 63 (67)

    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.

  • 2017. Rebecca S. Stutz (et al.). Forest Ecology and Management 390, 1-7

    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.

  • 2016. Ulrika Alm Bergvall, Lisa Svensson, Petter Kjellander. Behavioural Processes 128, 58-63

    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.

  • 2015. L. Debeffe (et al.). Animal Behaviour 109, 53-63

    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.

Visa alla publikationer av Ulrika Alm Bergvall vid Stockholms universitet

Senast uppdaterad: 18 juli 2018

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