16 research outputs found
Mammals show faster recovery from capture and tagging in human-disturbed landscapes
Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4â7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals
Olfactory communication in red foxes {Vulpes vulpes)
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Spatial and behavioral changes by red foxes (Vulpes vulpes) in response to artificial territory intrusion
Urine marking is thought to play a pivotal role in territory demarcation by red foxes (Vulpes vulpes (L., 1758)), but little is known about how individuals respond to alien scent marks, and whether there are sex-related differences in territorial defense. We radio-tracked dominant male and female urban foxes before and after synthetic fox urine was applied to approximately a third of their territories and compared spatial and behavioral reactions both before and after scent application
and with foxes on territories where no urine was applied. Home-range boundaries of male foxes shifted towards the
scent-marked area, but this change did not affect the total territory size. Larger males shifted their home ranges to a greater degree than small males. Scent application did not affect total activity, but males spent more time in the scent-marked area. Behaviors such as distance moved per night and speed of movement did not differ before and after application, but foxes searched a greater percentage of their home range each night following scent marking. Females showed no significant spatial or behavioral response to the synthetic scent marks. Overall, responses of foxes to synthetic scent marks were male-biased
and related to changes in space use rather than movement behaviors
Advanced roe deer (Capreolus capreolus) parturition date in response to climate change
In temperate habitats, the vegetation onset in spring affects the life cycle activities of large herbivores. For one species of large herbivore, roe deer (Capreolus capreolus), parturition is tied to peak resource availability. However, recent long-term studies of the parturition date of roe deer found only limited support for its earlier occurrence with an earlier onset of spring. In this study, data from a long-term project (1973â2019) in southern Germany (Baden-WĂŒrttemberg; elevation 101â1036âm; 16,130 tagged roe deer fawns) were used to investigate whether the advance in the roe deer parturition date reflected different environmental conditions and was thus explained by temporal and spatial factors. Our results showed a consistent advance toward an earlier parturition date (between 0.16 and 0.33âd/yr), especially for elevations above 750âm, that coincided with an advance in plant phenology. Up to 37% of the variance of the detrended time series of the mean annual parturition was accounted for by the detrended time series of the flowering date of forsythia. Our results suggest a plasticity that allows roe deer to cope with climate-induced changes along environmental gradients
Evidence for a maleâbiased sex ratio in the offspring of a large herbivore: The role of environmental conditions in the sex ratio variation
Numerous studies have examined whether the primary and/or secondary sex ratio in mammals, including humans, deviates from an equilibrium of 1:1. Although effect size in the sex ratio variation is expected to be low, a large sample size allows the identification of even small deviations from parity. In this study, we investigated whether the sex ratio of roe deer (Capreolus capreolus) offspring at birth approaches parity, using a large data set from roe deer offspring tagged in Baden-WĂŒrttemberg (Germany, 1972â2019, N = 12,437). In addition, a systematic re-analysis of available data on the secondary sex ratios of roe deer was conducted to test whether our finding withstood the accumulation of further data. The null hypothesis that the sex ratio of roe deer (prenatal sex ratio and sex ratio at birth) approaches parity was rejected. Moreover, the secondary sex ratio of roe deer offspring deviated from the male-biased mean for relatively cold or warm weather conditions during autumn and winter. Our study provides strong evidence for a male-biased sex ratio in a large herbivore and weak evidence for variations in the secondary sex ratio owing to environmental conditions. The pattern is highly relevant in the context of climate change and its impact on the population dynamics of large herbivores
Anthropic pressure drives resource selection of an adaptable generalist in humanâdominated landscapes
Abstract Few landscapes on earth remain free of humanâmodification, which may influence resource selection in wildlife. To investigate the effects of anthropic pressure on wild boar (Sus scrofa) and explore management implications, we studied how diel resource selection of the species' main life stages changed with spatial variations of human access (e.g., for recreation), temporal changes in hunting pressure, and habitat type. Using 206,461 hourly GPSâlocations of 15 males, 11 females with dependent young, and 17 other females from southâwestern Germany, we found anthropic pressure influenced resource selection more than ecological factors. All boars were more likely to select for low humanâaccess areas than high humanâaccess areas, regardless of habitat. Hunting pressure was most avoided by females with dependent piglets, followed by males and other females. Since both hunting activity and general human access affected resource selection, they should be considered simultaneously in wildlife management and conservation. We suggest the further establishment of wildlife reserves that are inaccessible to people where boar may remain more localized, thereby reducing the risk of disease transmission, and boar hunting to focus on open lands and refuge boundaries to reduce crop damage. This may also benefit overall humanâwildlife coexistence, animal welfare, and biodiversity conservation in anthropized environments
Adaptation of wild boar (Sus scrofa) activity in a human-dominated landscape
Abstract Background Wild boars (Sus scrofa L.) are globally widely distributed, and their populations have increased in Europe during recent decades. Encounters between humans and wild boars are rare because of the predominantly nocturnal lifestyle of the latter, and wild boar management by hunting is a challenging task. Animal activity patterns are important for understanding the behaviour of a species. However, knowledge of detailed temporal patterns and an understanding of the drivers of wild boar activity at a fine temporal scale are lacking. Of special relevance for humanâwild boar interactions (e.g., encounters, conflicts, and management) is the question of whether nocturnal activity depends on anthropogenic factors and, particularly, how local hunting regimes may affect activity patterns. We used GPS telemetry and acceleration measurements to shed light on this part of wild boar behaviour, observing 34 animals in Central Europe. Animals were tracked along a gradient of hunting pressure from hunting-free areas to areas with low or high hunting pressure. Fitted generalised additive models allowed predicting the probability of active behaviour under differing disturbance regimes precisely to day of year and time of day. Results The wild boars were predominantly nocturnal, with peak activity at approximately midnight. However, the data showed increased activity during daylight for wild boars that used no-hunting zones or reduced-hunting zones. Large areas with low disturbance levels promoted activity during daylight more than smaller areas with an intermediate disturbance regime. High air temperatures and locations within forests reduced the probability of active behaviour, whereas proximity to tracks used for forestry or agriculture was accompanied by a higher probability of activity. Conclusions We conclude that wild boars flexibly adjust their activity to their local environmental conditions, considering disturbances at the scale of long-term home ranges as well as actual small-scale landscape quality. Entire wild boar home ranges should be covered in the delineation of reserves intending to stimulate activity during daylight
The role of information presentation for wildlife knowledge, attitude, and risk perception
Abstract Public opinion can have a decisive influence on conservation actions leading to a need to understand how public opinion is formed. In a survey with a representative sample of the German population, participants answered questions about foxes in two consecutive years. Different versions of a leaflet about foxes were distributed to 2448 participants before the second interview. We compared a narrative text presentation to a nonânarrative list of facts and examined the use of photographs and schematic graphs. We assessed how the presentation format and socioâdemographic factors affected the probability that participants read the leaflet. Using a beforeâafter/controlâimpact design, we examined whether the leaflet affected people's foxârelated knowledge, attitude, and risk perception. The results show that participants were more likely to read the leaflet with increasing age and a higher educational level. Reading probability also increased with attitude toward foxes. Participants who read the leaflet completely gained more knowledge about foxes than those who read it only partly. Photographs also contributed to a higher knowledge gain, but schematic graphs did not. Moreover, participants who read a fact list gained more knowledge compared to the control condition. Furthermore, the combination of visual and textual features had an effect on attitude toward foxes. However, we found no evidence that any treatment affected risk perception. We discuss implications and derivations for science communication to improve conservation actions
Accelerometer-based detection of African swine fever infection in wild boar
Infectious wildlife diseases that circulate at the interface with domestic animals pose significant threats worldwide and require early detection and warning. Although animal tracking technologies are used to discern behavioural changes, they are rarely used to monitor wildlife diseases. Common disease-induced behavioural changes include reduced activity and lethargy (âsickness behaviourâ). Here, we investigated whether accelerometer sensors could detect the onset of African swine fever (ASF), a viral infection that induces high mortality in suids for which no vaccine is currently available. Taking advantage of an experiment designed to test an oral ASF vaccine, we equipped 12 wild boars with an accelerometer tag and quantified how ASF affects their activity pattern and behavioural fingerprint, using overall dynamic body acceleration. Wild boars showed a daily reduction in activity of 10â20% from the healthy to the viremia phase. Using change point statistics and comparing healthy individuals living in semi-free and free-ranging conditions, we show how the onset of disease-induced sickness can be detected and how such early detection could work in natural settings. Timely detection of infection in animals is crucial for disease surveillance and control, and accelerometer technology on sentinel animals provides a viable complementary tool to existing disease management approaches.publishe