Dominique Pépin

ASSESSING REAL DAILY DISTANCE TRAVELED BY UNGULATES USING DIFFERENTIAL GPS LOCATIONS

Abstract Differential Global Positioning System technology can provide series of accurate locations of free-ranging animals with a short, fixed interval. The sum of straight-line distances between valid locations (y) plotted against number of attempted fixes per day (x) should fit a hyperbolic function (i.e., y = x/[ax − b]) after removing inaccurate fixes and inactive periods. Its asymptotic value (1/a) can provide an estimate of real travel distance. The ratio of 1/a and y is a correction factor to apply to perceived straight-line distance to estimate real distance traveled. We achieved a good model fit on free-ranging adult red deer (Cervus elaphus) from data obtained every 15 min for a male and a female in winter 1997–1998, with a narrow range of correction factors. To validate this model, we used independent datasets from 3 other adult red deer roaming in the same area in winter 2000. We applied the procedure to distances perceived with fixed intervals ranging from 30 to 240 min and found consistent results in estimated real distances. Application of various steps of this analytical method could further development of a general approach to assess real distance traveled by individuals, thus offering new ways of studying habitat use or energetic requirements.

Selection of resting sites by the European hare as related to habitat characteristics during agricultural changes

The decline of the European hare Lepus europaeus populations has been shown to be correlated with agricultural intensification, which has caused loss of habitat heterogeneity. We aimed to investigate the diurnal spring habitat selection using Jacobs’ second selection index in an intensively cultivated farmland to reveal how the habitat choice by resting hares was affected by changes in the habitat availability. Clearance counts of hares driven out of known areas were made during an 11-year field investigation within two sectors of a private hunting ground located in the Paris basin (France). The loss of habitat heterogeneity included the disappearance of pastures dedicated to a last remaining sheep farm in the area, the removal of non-cropped areas and field boundaries and the increase of mean field size. Breeding stocks of hare declined during the study. Harrowed fields were always avoided. Pastures, alfalfa fields, thickets and fallow land were selected at the start of our study, whereas the remaining part was avoided at the end. The preference for ploughed fields decreased with the growth of vegetation in the winter-wheat fields. To benefit hares, land management should provide year-round vegetative cover and food from non-cropped areas in intensive arable farms.

Individual variation in migratory and exploratory movements and habitat use by adult red deer (Cervus elaphus L.) in a mountainous temperate forest

Using data from a global positioning system (GPS), seven adult red deer (Cervus elaphus L.) were tracked in the Parc National des Cévennes, southern France, between November 1998 and December 2000 to assess the factors affecting large-range movement patterns and habitat use. The home range varied from a single compact area for females to three distinct seasonal ranges for males, which used alternative migratory strategies (i.e. non-, downward- and upward-migrants). The migrants used mainly southerly and easterly aspects, and wintered in areas having steeper slopes than were used during summer or the rut season. For males, the time of rut migration was mid-September and they finally entered wintering ranges from mid-December to the beginning of January. Exploratory behaviour (i.e. individuals found outside the limits of their familiar area but returning to it a few days later) occurred in both sexes and for all individuals monitored during at least a 6-month period. Velocity and efficiency of exploratory movements were higher than usual movements. During these exploratory movements, hinds may have used different landscape attributes (elevation, slope, canopy cover) while stags did not. These results provide new empirical information that could be used for building and applying broad-scale spatial and landscape use models in ecological research.

Seasonal and daily walking activity patterns of free-ranging adult red deer (Cervus elaphus) at the individual level

We studied the walking activity over the year of free-ranging adult red deer (Cervus elaphus) in a mountainous area with the aim of describing the dynamics of movement patterns at the individual level. We monitored the distance walked by two males and two females fitted with global positioning system collars to test the hypothesis that deer adopt behaviours to reduce costs of locomotion. We predicted that both sexes would travel less in winter when disadvantageous environmental conditions occurred. We also predicted that the males would (1) reduce their movement soon after the rut due to very high energy expenditure during the breeding season and (2) travel less than the females due to their larger body mass. As we expected, minimum walking activity occurred after the rut from November to February for the males and in late February for the females. The walking activity of males peaked during the rut whereas that of females decreased. But compared to males, females moved more both during winter and daylight hours. Although our study stems from just four individuals, these results and the methodology used can be inspirational for red deer research as well as for ungulate research in general.

Seasonal Variation in Intragroup-Spacing Behavior of Foraging Isards (Rupicapra pyrenaica)

Some aspects of the intragroup-spacing behavior in isards ( Rupicapra pyrenaica ), mainly in foraging herds of females with kids and young, were investigated by scan-sampling methods in a Pyrenean reserve from October 1986 to June 1987. Within herds, adults of both sexes tended to be peripheral, whereas the kids were central. The spatial proximity between animals in groups was maximum during the breeding period (June), and minimum during winter (February). Mean nearest-neighbor distances between adult females and between females and kids increased with age of kids. Season, group size, and spacing pattern of females are related.

Red deer Cervus elaphus resting place characteristics obtained from differential GPS data in a forest habitat

We recorded 30 24-h monitoring periods with 10-min sampling intervals on seven (three female; four male) Global-Positioning-System-collared adult free-ranging red deer (Cervus elaphus), from June 1999 to December 2000, in the Parc National des Cévennes, France. We observed the duration of resting bouts (n = 385) and then microhabitat variables (aspect, slope, presence of edge and litter, visibility, abundance of vegetation consumed or not) at 178 resting places. Resting bouts were shorter during the night than during the day from June to October but did not vary between sexes. Resting place visibility was lower during the day, especially in August. Daytime resting places generally offered more litter. Females used steeper slopes than males. We found higher variability in visibility and slope during the night. Aspect used did not vary from month to month or between day and night. Observed differences between day and night resting place characteristics suggest that red deer were probably facing a tradeoff between feeding and cover. Use of cover prevailed during the daytime whereas night resting place characteristics were more variable, indicating less constrained behaviour. Thus, cover (as a protection from disturbance), as well as food, is an important factor in red deer habitat use (at least during the day in disturbed areas) and should not be neglected in forest carrying capacity management.

Diurnal and seasonal variations of roaring activity of farmed red deer stags

Various environmental and social parameters are known to affect the roaring activity of the red deer (Cervus elaphus) stags, but their influence is difficult to estimate in the field. We consequently studied the diurnal changes in roaring activity of three adult stags kept in separate paddocks with hinds over the course of a breeding season during seven 24 h field sessions. Roaring activity started at the end of September, peaked for all three stags in mid-October before ceasing abruptly about a week later. Both the hourly number of roar bouts and the hourly number of roars emitted differed between stags and sessions: the youngest (5-year-old) stag roared more at the beginning of the rut, while roaring of the two other stags (11- and 12-year-old) progressively increased over the season. However, at the peak, the roaring activity of the three stags was similar. During the two first weeks of October, the roaring activity of the two more vocal stags significantly decreased just before sunrise and at least 2.5 h after sunset, while it significantly increased during daytime. The implications of these results for estimating the population size of free ranging red deer based on roaring activity of stags are briefly discussed.

Factors Affecting the Relationship between Body Mass and Age in the Izard

We investigated the influence of gender, capture period, and between-year variation on the relationship between body mass and age in the izard ( Rupicapra pyrenaica ) using data obtained on 201 individuals captured in a Pyrenean reserve, France. Body mass was measured in spring or autumn 1984–1993. Absence of sexual dimorphism in body mass probably resulted from the high density of this protected population. Strong quadratic relationships between age and body mass were observed for spring and autumn ( r 2 = 0.79 and 0.76, respectively). Izards exhibit lower body mass in spring than in the previous autumn irrespective of age class. No significant between-year variation occurred in body mass in autumn. There were marked differences between years in spring that may be related to previous climatic conditions in winter, particularly daily temperature in December and total snowfall from November to April.

Human-related disturbance risk and distance to cover affect use of montane pastures by Pyrenean chamois

Abstract The influence of a hiking trail and the edge of a surrounding beech forest on the diurnal habitat use patterns of the Pyrenean chamois (Rupicapra pyrenaica) was studied within montane pastures of a protected area during a mild winter. Habitat selection significantly increased as the distance from these two landscape features increased, a greater range of variation being found for the trail. Then to test their combined influence, seven non-overlapping sectors were delineated. Not surprisingly the most avoided sector was less than 100 m from both the trail and the forest. By contrast, the most selected part was located between 200 and 300 m from the trail and over 100 m from the forest, where the mean group size peaked at 18. Nevertheless, the negative influence of the edge of the beech forest was counterbalanced when Pyrenean chamois were at a distance greater than 300 m from the trail, the number of groups there being the highest. Human-related disturbance risk require people on foot to remain on established hiking trails because Pyrenean chamois might perceive their activities as predictable and thus more acceptable.

Diurnal grouping and activity patterns of the Pyrenean chamois in winter

The relationships between group size, activity patterns, and time of day were studied during a mild winter in a protected population of Isard or Pyrenean chamois (Rupicapra pyrenaica pyrenaica) in open montane pastures in the bottom of a central valley, bordered by a beech forest. The size and the total number of groups increased progressively from dawn to the middle of the afternoon. Nearly half of the animals foraged early in the morning, while about two out of five were moving. As the day proceeded, the allocation of time for foraging increased regularly until approximately 3/4 of the animals were observed foraging at about 17:00. Foraging increased initially at the expense of moving, and later to both moving and standing. Then, just before dusk, both group size and time devoted to foraging decreased, as individuals returned to the beech forest to rest during the night in a sheltered habitat. The relative influence of weather conditions and of the digestive physiology of Pyrenean chamois on this spatio...