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Habitat use and movements of plains zebra (Equus burchelli) in response to predation danger from lions
Abstract and Figures
Prey species must adapt their behavior to avoid predation. As a key prey item for lions (Panthera leo), plains zebras (Equus burchelli) were expected to respond to immediate threats posed by lions in their area. In addition, zebras were predicted to exhibit behavior tuned to reduce the potential for encounters with lions, by modifying their movement patterns in the times of day and habitats of greatest lion danger. We studied a population of approximately 600 plains zebra living in Ol Pejeta Conservancy, Kenya. We found that zebra abundance on or near a grassland patch was lower if lions had also been observed on that patch during the same day. Predation danger was highest in grassland habitat during the night, when lions were more active. Zebra sightings and global positioning system radio collar data indicated that zebras also reduced their use of grassland at night, instead using more woodland habitat. Zebras moved faster and took sharper turns in grassland at night. It is hypothesized that these more erratic movements assist zebras in avoiding detection or capture by lions. Copyright 2007, Oxford University Press.
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... The observations of the present study may support a previous assumption, that Central European horses may not have lost their abilities to deal with wolves that do not attack, even though they did not experience predator contact in the past centuries [27][28][29][30]. It confirms observations in natural settings, in which a coexistence of equids and non-hunting predators was frequently observed [37]. However, the present observational study can,not conclude on the horses' emotional stage and welfare at wolf contact. ...
Wolves returned to Germany in 2000, leading to fear in German horse owners that their horses could be in danger of wolf attacks or panic-like escapes from pastures when sighting wolves. However, reports from southern European countries indicate that wolf predation on horses diminishes with increasing presence of wildlife. Therefore, we conducted a long-term, filed observation between January 2015 and July 2022 on 13 non breeding riding horses, mares and geldings, kept permanently on two pastures within the range of wildlife and a stable wolf pack with annual offspring. Wildlife cameras at the fences of the pastures made 984 times recordings of wolves and 3151 times recordings of wildlife in and around the pastures. Between 1 January 2022 and 23 March 2022 we observed two stable horse groups. Pasture 1 was grazed by five horses of mixed breed, four mares and one gelding, with the median age of 8 years (min. = 6y, max. = 29y). Pasture 2 was grazed by eight heavy warmbloods and draught horses, three mares and five geldings, with the median age of 16 years (min. = 13y, max. = 22y). During this period no wolf was recorded at pasture 2, but wild boar several times, whereas at pasture 1, wolves were recorded 89 times, and for the wildlife mostly hare. Wolves may have avoided pasture 2 because of the presence of wild boar or because the large group of older, heavy breed horses may have formed a stable, protective group. The latter needs to be confirmed in a follow-up field observation, which records anti-predator behavior and welfare indicators in horses. In conclusion, wolves did not attack the mature horses on pastures with plenty of wildlife and the horses did not respond to the presence of wolves with visible signs of reduced welfare or panic. This indicates that wolves may prefer to prey on easily accessible wildlife around and at horse pastures and that Central European horses become accustom to the presence of non-hunting wolves.
... Observational data, as well as enamel isotope data, have previously been collected on the zebra inhabiting Ol Pejeta, and the greater Laikipia Plateau (Fischhoff et al., 2007). Two species of zebra inhabit the Laikipia Plateau, the Plains zebra (Equus quagga), which is sampled in this study, and the endangered Grévy's zebra (Equus greyvi). ...
Seasonality shapes environments by driving vegetation patterns and faunal community composition, and identifying seasonality patterns in the past can provide unique insight into paleoenvironments and how they changed over time. Many environmental proxies operate on too large a time scale to glean data about intra-annual seasonality. However, serial enamel isotope samples from the teeth of high-crowned ungulates show promise for providing this temporal resolution of data. Interpreting these data remains a challenge due to the complexity of factors related to animal physiology and the isotopic values of environmental inputs. This study seeks to establish a method for interpreting intra-tooth isotopic change in modern equid teeth as a signal of seasonality by applying a linear mixed effect model to the isotope data to detect periodicity in serial enamel isotope values. Using a modern assemblage of zebra (Equus quagga) from Ol Pejeta Conservancy in Kenya, where long-term climate data has been collected, allows us to compare known climatic seasonality patterns to periodicity in the zebra tooth enamel isotopes. The results of the linear mixed effect modeling, in tandem with the climate data from Ol Pejeta, demonstrate the impact high precipitation variability can have on an environment. While our isotope results point towards measured precipitation seasonality patterns at Ol Pejeta, noise in our data and the variation identified by the models illustrate the challenges of working with serial enamel isotope data. Future refinement and application of this model will allow us to better characterize seasonality in both modern and fossil enamel datasets.
... The niche compression can potentially increase interspecific competition and also lead to physiological effects on the prey (Dänhardt & Lindström, 2001). For instance, an impact of predatory risk has been observed in the behaviour of ungulates with cascade consequences on the vegetation (Creel et al., 2005;Gude et al., 2006;Forester et al., 2007;Beyer et al., 2007;Fischhoff et al., 2007). In this group of animals, the availability and quality of foraging areas may be a factor in the level of physiological stress experienced as a result of differences in diet that may impact the glucocorticoid concentration . ...
Unlabelled:
In a development of the ecosemiotic vivo-scape concept, a 'safety eco-field' is proposed as a model of a species response to the safety of its environment. The safety eco-field is based on the ecosemiotic approach which considers environmental safety as a resource sought and chosen by individuals to counter predatory pressure. To test the relative safety of different locations within a landscape, 66 bird feeders (BF) were deployed in a regular 15 × 15 m grid in a rural area, surrounded by shrubs, small trees, hedgerows, and buildings. On each of 48 days in November 2021 and February and March 2022, dried mealworms were placed on each BF and counts of larvae at each BF were made at noon and dusk. The European robin (Erithacus rubecula) and the great tit (Parus major) were the most regular visitors to the BFs. Land cover at each BF was recorded. Bird behaviour at the BFs was noted from direct video recordings of the birds at nine selected BFs, totalling 32 daily sessions in March. The different behaviours of the European robin and the great tit were observable. The safety eco-field changed according to the month and the time of day. The distance of the BF from the woodland edges seemed to be important only in the morning. In the afternoon, BFs that were more distant from the woodland edges received the highest number of visits. Weather conditions were found to influence the number of mealworms removed, but this requires further investigation. A significant relationship between land cover and the number of mealworm larvae removed from the BFs was observed. Within the grid of BF, three regions were distinguishable which were related to land cover in the safety eco-field process. The experimental framework confirms the adequacy, at least for birds that have cryptic predators, to map the landscape as a proxy of safety resource. From the video recordings it was noted that the European robin visits were distributed throughout the day without apparent temporal preferences, while the great tit visits were concentrated in the central part of the day. This result has the limitation of the short period of observation (March) and should be extended to the entire period of the experiment to eventually capture seasonal variation. The experimental evidence obtained confirms that the ecosemiotic-based models of safety eco-field are an efficient approach to explain bird feeding preferences and behaviours.
Supplementary information:
The online version contains supplementary material available at 10.1007/s12304-023-09522-1.
... Movement is a major component of animals' lives. It allows individuals to find resources, such as food or mates (Greenwood, 1980;Janson & Di Bitetti, 1997), and escape from predators (Fischhoff et al., 2007;Morton et al., 1994). However, the benefits of movement are also counterbalanced by energetic costs (Shepard et al., 2013;Taylor et al., 1982). ...
... Core areas for the connectivity models were identified using kernel densities of resources use areas (Beier et al., 2008). In the absence of data for Grevy's zebra, resource-use movement behaviour was defined from plains zebra, with a mean speed of >1.1 km/h walking to forage, >1.5 km/h walking to water and mean speeds of 0.3 km/h within a forage patch (Brooks et al., 2008;Fischhoff et al., 2007). Grevy's zebra GPS locations were filtered by speed (<1 km/h) and assumed to be foraging or stationary. ...
Land degradation, competition with livestock, infrastructure development, and climate change have reduced habitat availability and reduced population connectivity for many wildlife species. Large herbivores are particularly vulnerable, and approximately 90 % of global large herbivore diversity is in Africa. The endangered Grevy's zebra illustrates the decline and fragmentation of large mammalian herbivore populations, with extensive population loss across their range in northern Kenya and Ethiopia. A better understanding of the factors influencing population connectivity and movement patterns of Grevy's zebra, highlighted in national strategies, offers valuable insights for other threatened species.
Using location and movement data for Grevy's zebra from GPS collars deployed between 2010 and 2017, seasonally-explicit landscape resistance was modelled as a function of water availability, vegetation, cattle density, topography and proximity to roads and settlements. Maximum entropy models identified habitat suitability during wet and dry seasons respectively. Population connectivity analyses using least-cost paths and circuit theory determined landscape resistance to movement and highlighted linkage pathways. Movement was modelled over a range of distances, using GPS data.
Grevy's zebra reliance on water was confirmed, with an apparent trade-off between habitat suitability and proximity to people. Connectivity models highlighted potentially isolated populations, with reduced seasonal connectivity being most apparent between north to south distribution areas. These results can inform sustainable land management planning in northern Kenya and offer support for Grevy's zebra conservation actions. These results also provide insights that can be applied to other large herbivores occurring in this region and in arid or degraded environments elsewhere.
... These changes in movement patterns can include changes in speed, direction, tortuosity, elevation, and distance moved. For example, in response to the presence of predators, caribou increase speed and move towards closed foraging areas when wolves are within two kilometres , plains zebra increase speed and turning angles at night on grassy plains, which has been linked to lion ambush risk (Fischhoff et al., 2007), elk increase distance travelled in response to wolves and hunters, and blue wildebeest increase speed and travel more linearly when being pursued by coursing predators (Dröge et al., 2019). Prey species may also make movement decisions in response to vocalisations made by dangerous predators. ...
Human-carnivore conflicts occur globally and are a leading cause of carnivore population declines. Such conflicts usually occur when carnivores predate livestock and can include preemptive and retaliatory killing of carnivores by livestock farmers. In northern Botswana, livestock farming is a widespread and culturally important practice. Subsistence farming enterprises commonly abut protected areas, and human-carnivore conflicts are common. Understanding interactions between livestock and carnivores, and how livestock use resources and habitats generally, are important components to managing these conflicts. Throughout this thesis, I explore human-carnivore conflict in northern Botswana. I found that livestock resource selection and predation vary seasonally and spatially in relation to ecological and anthropogenic features in the landscape. Predation sites are subsequently avoided by cattle in the short-term, but not by goats. Contemporary mitigation to minimise livestock predation events commonly includes lethal control and broadscale exclusion by artificial barriers and aversive interventions, yet naturally occurring deterrent signals fine-tuned through evolution are rarely considered. Lions roar to deter conspecifics from territorial boundaries, which prey and subordinate carnivores eavesdrop on and modify their movement and behaviour in response. I used lion vocalisations to understand livestock (prey) responses to this apex carnivore and to test how effective roars are in deterring lions and other carnivores. Using a high-tech experimental approach, I found that (1) cattle avoid lion vocalizations, while goats do not, and (2) lions are not deterred by lion roars played-back from Remotely Operated Acoustic Repellent stations (ROARs), nor are other human-carnivore conflict species occurring in the area. Finally, I used a commonly occurring anti-predator signal in nature, demonstrating that artificial eyespots painted on cattle rumps deter lions from attacking cattle. Collectively, the results from my thesis can be used to better manage livestock in a landscape of risk, and to promote human-carnivore coexistence by deterring predation. Applications derived from my thesis to promote human-carnivore coexistence can be used across Africa and the globe.
It is often assumed that because predators typically consume large numbers of prey, they automatically control prey population sizes and help shape the evolution of their prey’s distinctive traits. Examining the evolutionary history, ecology, and behavior of equids challenges these assumptions. A suite of morphological traits appears to be a response to changing climates, habitat opening and selection for lowering locomotory costs, not to the emergence of pursuit predators. And while predation can drive down equid numbers locally, large regional populations and the fact that predators do not specialize on equids, suggests that most extant equid populations will stabilize, or even grow, unless other factors control population numbers. Behaviors enhancing equid survival come in a variety of forms: living in groups automatically dilutes the risk of being the one eaten if predators successfully kill one group member; sharing vigilance to maintain a level of personal protection without forgoing other activities such as grazing; adjusting daily activity schedules to balance risk without paying for lost foraging opportunities; changing habitats when predators are detected prior to an attack; maintaining cohesion or confusing predators while fleeing; or even staying put and fighting back when early detection fails. Which of these many adaptations will be deployed will depend not only on each species’ suite of physical traits and how its society is structured, but also on an individual’s reproductive or nutritional state as well as on features of the environment.
Introduction
Predators can affect prey not only by killing them, but also by causing them to alter their behavior, including patterns of habitat selection. Prey can reduce the risk of predation by moving to habitats where predators are less likely to detect them, less likely to attack, or less likely to succeed. The interaction of such responses to risk with other ecological processes remains relatively unstudied, but in some cases, changes in habitat use to avoid predation may be constrained by competition: larger, dominant competitors should respond freely to predation risk, but the responses of smaller, subordinate competitors may be constrained by the responses of dominant competitors. For large grazing herbivores, an alternative hypothesis proposes that smaller prey species are vulnerable to more predators, and thus should respond more strongly to predation risk.
Methods
Here, we tested these two hypotheses with 775 observations of habitat selection by four species of obligate grazers (zebra, wildebeest, puku and oribi) in the immediate presence or absence of four large carnivores (lion, spotted hyena, African wild dog and cheetah) in three ecosystems (Greater Liuwa, Greater Kafue and Luangwa Valley). Patterns of predation within this set were described by observation of 1,105 kills.
Results
Our results support the hypothesis that responses to predation risk are strongest for larger, dominant competitors. Even though zebras were killed least often, they showed the strongest shift into cover when carnivores were present. Wildebeest, puku and oribi showed weaker habitat shifts, even though they were more frequently killed. These patterns remained consistent in models that controlled for differences in the hunting mode of the predator (stalking, coursing, or intermediate) and for differences among ecosystems. There was no evidence that smaller species were subject to predation by a broader set of predators. Instead, smaller prey were killed often by smaller predators, and larger prey were killed often by larger predators.
Discussion
Broadly, our results show that responses to predation risk interact with interspecific competition. Accounting for such interactions should help to explain the considerable variation in the strength of responses to predation risk that has been observed.
Analysing social networks is a powerful tool for understanding the ecology of social species. While most studies focus on the role of each group member, few compare groups with different characteristics. The current population of Przewalski's horses Equus ferus przewalskii at the Great Gobi B Strictly Protected Area (Mongolia) includes groups of wild-born and captive-bred individuals with different experiences with the area (acclimatizing, long-term reintroduced and wild-born), therefore serving as an ideal natural behavioural lab. We filmed 11 groups for 141.5 hours in summer 2018 (July), late spring 2019 (May, June), and autumn 2019 (September, October). Affiliative and agonistic interactions were recorded, and social networks were created. We tested the influence of origin, experience, season, sex, age, relative time belonging to the group, relatedness, and dominance rank on different network indices at the individual and group levels. We found that groups with greater experience in the area are generally better connected than members of the newly formed groups. However, these strong networks were created by wild-born individuals with very low interaction rates. On the contrary, inexperienced groups composed of captive-bred individuals displayed many interactions but created weak social networks. The results show a trend of behavioural transition from acclimatizing through long-term reintroduced to wild-born groups, supporting that the newly-formed groups of released Przewalski's horses need time to display the typical social behaviour patterns of wild-born individuals. Long-term monitoring of released Przewalski's horses is recommended to promote success of thisreintroduction program.
Conservation behavior assists the investigation of species endangerment associated with managing animals impacted by anthropogenic activities. It employs a theoretical framework that examines the mechanisms, development, function, and phylogeny of behavior variation in order to develop practical tools for preventing biodiversity loss and extinction. Developed from a symposium held at the International Congress on Conservation Biology in 2011, this is the first book to offer an in-depth, logical framework that identifies three vital areas for understanding conservation behavior: anthropogenic threats to wildlife, conservation and management protocols, and indicators of anthropogenic threats. Bridging the gap between behavioral ecology and conservation biology, this volume ascertains key links between the fields, explores the theoretical foundations of these linkages, and connects them to practical wildlife management tools and concise applicable advice. Adopting a clear and structured approach throughout, this book is a vital resource for graduate students, academic researchers, and wildlife managers.
This chapter examines the female social behaviour of four equid species (horse Equus caballus, plains zebra E. burchelli, Grevy's zebra E. grevyi and onager E. hemionus, which differ in their types of sociality. Females horses and plains zebras form long-term bonds within stable groups accompanied by a single male; female Grevy's zebras and onagers change associates frequently and form unstable groups with brief association with each of several territorial males. Females of all the species compete little while foraging. Rates of agonistic interactions, bite rate, and time spent feeding are generally unaffected by group size. Being species limited by time available for foraging, their females associate to gain foraging time; even their choice of male may be made for that reason. Fission-fusion society is a mere variant upon the theme of a society based on female association. -from Author
I used retrospective analyses to investigate relationships among terrain type, reactions of prey, and age and sex of prey and outcomes of encounters between mountain sheep (Ovis canadensis) and coyotes (Canis latrans). Adult females fled from coyotes more often when in open terrain and young always fled regardless of type of terrain. Young were less likely to survive encounters with coyotes than were adults, and no adult females were killed by coyotes. When types of terrain were pooled, females were more apt to flee than were males, but no difference existed in proportion of females and young that fled. When terrain type and sex of adults were pooled, no difference in survival existed between adults that fled and those that did not. When coyotes were encountered in open terrain, female mountain sheep fled more frequently than did female mule deer (Odocoileus hemionus). Ungulates less dependent on terrain for predator evasion than are mountain sheep may employ a more plastic strategy than artiodactyls inhabiting precipitous terrain.
Sexual Selection in Primates provides an account of all aspects of sexual selection in primates, combining theoretical insights, comprehensive reviews of the primate literature and comparative perspectives from relevant work on other mammals, birds and humans. Topics include sex roles, sexual dimorphism in weapons, ornaments and armaments, sex ratios, sex differences in behaviour and development, mate choice, sexual conflict, sex-specific life history strategies, sperm competition and infanticide. The outcome of the evolutionary struggle between the sexes, the flexibility of roles and the leverage of females are discussed and emphasised throughout. Sexual Selection in Primates is aimed at graduates and researchers in primatology, animal behaviour, evolutionary biology and comparative psychology.
The role of Panthera leo predation in the dynamics of blue wildebeest Connochaetes taurinus and zebra Equus burchelli populations was investigated through simulation models. Data used in the models were from observations in SE Kruger National Park. Model 1 ascertained the number of killing lions (adult females) that could be supported by each prey population while remaining stable. A single model was constructed for the sedentary wildebeest population. A summer and winter model was constructed for the semi-migratory zebra population. The sensitivity of the parameters in the model was tested by changing their value by 10%. In model 2, the kill age structure for each species was changed to determine the number of killing lions the altered prey selection parameters could support. There was no difference in the vulnerability of either species to predation. Zebra foals (<1 yr) were killed more frequently than expected. No selection for sex or by season could be found for either species. Model 1 predicted that the wildebeest population stabilizes with 7.7 killing lions, close to the number in the study area. The winter zebra populations stabilizes with 6.8 killing lions and the summer zebra population with 19.4. Manipulation of kill rate followed by adult fecundity rate had the greatest effect on population size of both species. In model 2, wildebeest predation was made selective towards calves and zebra predation was made non-selective for sex and age. With these parameters the wildebeest population stabilizes with 10.7 killing lions and the zebra population with 5.4 in winter and 15.1 in summer. The models suggest that lion predation affected wildebeest more severely than zebra during the study. This was through the way in which lions selected their prey, and because of the sedentary behaviour of the wildebeest, as opposed to the semi-migratory behaviour of the zebra. -from Authors
The so-called 'inefficiency' of the perissodactyls, resulting from the evolution of a cecal site of fermentation, arises because the strategy of selecting fibrous herbage was developed early in their evolution. The ruminant artiodactyls did not adopt this sort of diet until they were of a sufficiently large body size for a rumen fermentation site to be physiologically possible. It appears that body size at the time of the adoption of a fibrous diet is the critical factor in determining the type of digestive system that will be evolved. Cecal digestion is in fact the superior adaptation for dealing with high fiber content herbage, provided that intake is not limited by the actual quantity of herbage available. The Equidae continued to be successful in the face of the radiation of ruminant artiodactyls because they could maintain themselves on herbage more fibrous than could be tolerated by a ruminant of similar body size.
Long-term continuous observations of hunting lions Panthera leo in the Kruger National Park were used to assess the variables affecting hunting success of male and female lions. Generalized linear models revealed that seven variables had significant independent influences on hunting success, with the most important being the prey species hunted. Three types of variables were recognized: (1) lion related, where type of hunt, wind orientation, and the number of adults hunting; (2) prey related, where prey species and herd size; (3) environment related, where moon brightness, and grass height were significant. The sex of the lions had no effect on the overall probability of hunting success. Five second-order interactions significantly influenced the probability of hunting success, with the most important being the interaction between sex and the type of prey. The only significant third-order interaction containing the variable sex, was the inter-relationship with prey species and shrub cover. After removing the over-riding bias of the prey species, greater resolution of the factors affecting success was revealed. The major difference was that group size influences hunting success and concomitantly prey selection, promoting selection for medium-sized ungulates like zebra Equus burchelli and wildebeest Connochaetes taurinus by females, and males mainly capturing buffalo Syncerus caffer. We conclude that in African ecosystems, the hunting success of male and female lions varies with a range of combinations of lion-, prey- and environment-related variables. We demonstrate the hunting ability of male lions, which has perhaps been understated in other studies.
Preface; 1. The purpose of the book; 2. Survey of contents; 3. How to
use the book; 4. Notation, terminology and conventions; 5.
Acknowledgements; Part I. Introduction: Part II. Descriptive Methods:
2.1. Introduction; 2.2. Data display; 2.3. Simple summary quantities;
2.4. Modifications for axial data; Part III. Models: 3.1. Introduction;
3.2. Notation; trigonometric moments; 3.3. Probability distributions on
the circle; Part IV. Analysis of a Single Sample of Data: 4.1.
Introduction; 4.2. Exploratory analysis; 4.3. Testing a sample of unit
vectors for uniformity; 4.4. Nonparametric methods for unimodal data;
4.5. Statistical analysis of a random sample of unit vectors from a von
Mises distribution; 4.6. Statistical analysis of a random sample of unit
vectors from a multimodal distribution; 4.7. Other topics; Part V.
Analysis of Two or More Samples, and of Other Experimental Layouts: 5.1.
Introduction; 5.2. Exploratory analysis; 5.3. Nonparametric methods for
analysing two or more samples of unimodal data; 5.4. Analysis of two or
more samples from von Mises distributions; 5.5. Analysis of data from
more complicated experimental designs; Part VI. Correlation and
Regression: 6.1. Introduction; 6.2. Linear-circular association and
circular-linear association; 6.3. Circular-circular association; 6.4.
Regression models for a circular response variable; Part VII. Analysis
of Data with Temporal or Spatial Structure: 7.1. Introduction; 7.2.
Analysis of temporal data; 7.3. Spatial analysis; Part VIII. Some Modern
Statistical Techniques for Testing and Estimation: 8.1. Introduction;
8.2. Bootstrap methods for confidence intervals and hypothesis tests:
general description; 8.3. Bootstrap methods for circular data:
confidence regions for the mean direction; 8.4. Bootstrap methods for
circular data: hypothesis tests for mean directions; 8.5. Randomisation,
or permutation, tests; Appendix A. Tables; Appendix B. Data sets;
References; Index.