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1

Seasonal variation in group size of Cantabrian chamois in relation to escape terrain and food

100%
Perez-Barberia F. J., Nores C.
Acta Theriologica
|
1994
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tom 39
|
nr 3
The herd size of Cantabrian chamois Rupicapra pyrenaica parva (Cabrera, 1910) varied seasonally in relation to escape terrain and food availability in our study area (Asturias, north of Spain). The median group size of females without kids was 1 (mean ± SD = 1.62 ± 1.00), females with kids was 4 (5.59 ± 5.42), males was 1 (1.73 ± 1.78), and mixed group size was 7 (8.91 ± 7.91). The female-kid group size depended more on escape terrain availability than on food quality. Throughout the early weeks of the life of kids, the mothers remained in difficult access areas (cliffs and steep slopes), and showed a weak tendency to aggregate. These areas provided a wide visual range and hiding places for offspring and their use may be an anti-predation strategy. When the kids were able to run quickly, the mothers used subalpine meadows. These areas were very open and exposed kids to predation and human disturbance, however the forage has high nutritive value, and may compensate for the cost of breeding and suckling by the mothers. Aggregation may be selected as an anti-predation strategy in subalpine meadows, allowing a reduction in time spent vigilant by each individual in the group, and increased time available for other activities. The largest male groups were located in pastures with abundant but poor quality forage. Our results suggest that group size in Cantabrian chamois is very flexible, changing seasonally and in response to resource availability.
2

Teeth eruption pattern in Cantabrian chamois Rupicapra pyrenaica parva

100%
Perez-Barberia F. J., Mutuberria G.
Acta Theriologica
|
1996
|
tom 41
|
nr 2
A teeth eruption pattern for Cantabrian chamois Rupicapra pyrenaica parva (Cabrera, 1911) was presented (Cantabrian Mountains, North of Spain). Permanent teeth eruption order was as follows: (Mi M1) M2 M2 Ii M3 M3 (PM2 PM3) (PMi PM1 PM2 PM3 I2) I3 I4. The eruption time was: Mi and M1 at 2-3 months, M2 and M2 be­tween 9 and 13 months, M3 and M3 between 22 and 25 months. Lower and upper pre­molars and I2 emerged at 25-29 months. I3 emerged at 36-37 months, and the last tooth erupting was I4, between 36 and 46 months. The early eruption in Cantabrian chamois in relation to other chamois subspecies was discussed, and it was suggested that possible advantages relate to chewing efficiency and a wider age-related use of vegetation.
3

Horn growth pattern in Cantabrian chamois Rupicapra pyrenaica parva: Influence of sex, location and phaenology

81%
Perez-Barberia F. J., Robles L., Nores C.
Acta Theriologica
|
1996
|
tom 41
|
nr 1
Sexual dimorphism in Cantabrian chamois Rupicapra pyrenaica parua (Cabrera, 1911) horn length was recorded annually for the first five years of life. The horns of males were larger than those of females, though horn growth rate in the first two years (ie horn length in the first two years divided by horn length in the first five years) was greater in females than males. Sexual dimorphism in horn length of Cantabrian chamois adults was found to be the highest of genus according to available data. Males and females with faster horn growth in the first two years of life reduced their horn growth rate in the third and fourth year. Chamois' horns from the Eastern Cantabrian Mountains were smaller than those from Western Cantabrian Mountains, although at five years of age these differences were not evident. Total horn length and jaw length showed significant positive correlation (females: r^ = 0.75, males: rp2 = 0.54, p < 0.05 in both cases). This relationship suggests that horn growth dynamics may be used as an estimation of body-size dynamics. Horn growth / jaw length correlation was higher in females than in males. Horn growth was also positively correlated with annual precipitation in the previous year, but not with precipitation in the current year. Winter horn growth was observed in the younger age classes. Post-winter horn growth was recorded in 55% of the animals in March. The use of this information to age Cantabrian chamois is described.
4

Sex, seasonal and spatial differences in the diet of Cantabrian chamois Rupicapra pyrenaica parva

81%
Perez-Barberia F. J., Olivan M., Osoro K., Nores C.
Acta Theriologica
|
1997
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tom 42
|
nr 1
The relationships between availability and quality of food, diet composition and habitat use of female and male chamois herds Rupicapra pyrenaica parva (Cabrera, 1911), were investigated in the Cantabrian Mountains (Spain). The two vegetation types studied were grass-forb and shrub. Grass-forb contained higher crude protein and lower fibre than shrub throughout year (crude protein: 17.2% vs 8.6%, p = 0,018; acid detergent fibre: 27.0% vs 35.8%, p = 0.018). The diet of female and male herds showed more grass-forb than shrub (p = 0.012), however, a discrepancy between site selection and bite selection was found. Generally male herds were found in shrub areas although they mainly chose grass-forb in their diet. Female herds had a higher percentage of grass-forb in the diet than male herds throughout the year (81.6% vs 65.6%). Diet composition pattern was similar in both sexes, with a peak of grass-forb in spring and autumn, and a minimum in summer. Both sexes selecLed grass-forb throughout the year, but its use was increased when its quality was high, inde­pendently of quantity available. Females showed higher grazing activity than males throughout year (53% vs 37%, p < 0.0001). Male herds showed less grazing activity during the rut (October-November) in comparison with the rest of the year (25% vs 43%, p < 0.0001). Some hypotheses to explain the segregation of the herds of both sexes are presented and discussed.
5

Reproductive parameters, kidney fat index, and grazing activity relationships between the sexes in Cantabrian chamois Rupicapra pyrenaica parva

81%
Perez-Barberia F. J., Mutuberria G., Nores C.
Acta Theriologica
|
1998
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tom 43
|
nr 3
Reproductive parameters, kidney fat index and grazing activity of both sexes of Cantabrian chamois Rupicapra pyrenaica parua (Cabrera, 1910) in relation to age, season and year are presented and compared with those of other chamois subspecies and cervids. Females younger than three years old had not ovulated. Ovulated ovaries were significantly heavier than non-ovulated ovaries in March-April, and these dif­ferences remained until the following rutting season. All pregnant females carried a single foetus. A significant decrease in the percentage of parous females was found in 3-11 years age class (94%) compared with > 11 years (50%). There were no differences in the kidney fat index (KFI) between age classes for either of the sexes throughout the study period. Females showed a significant higher KFI in August­-October 1993 than in August-October 1992, coinciding with a significantly greater abundance of grass in 1993. Throughout the year KFI in females showed less fluc­tuations than in mates. Males began the rutting season with a significant KFI three times higher than did females. However, by the spring, the KFI of the mates had fallen to half of that of the females. In March-April pregnant females showed a significantly higher KFI than non-pregnant or late-conception adult females. Feeding activity of females and sward height throughout the year were inversely related. Females grazed more actively than males in the summer, rut and spring, except in winter where no differences in feeding activity between sexes were found. The dif­ferences in the KFI and feeding activity are discussed in relation to the parental investment and the sexual dimorphism-body size theory.
6

The effect of heather fragmentation and mixed grazing on the diet of sheep Ovis aries and red deer Cervus elaphus

71%
Cuartas P., Gordon I. J., Hester A. J., Perez-Barberia F. J., Hulbert J. A. R.
Acta Theriologica
|
2000
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tom 45
|
nr 3
The effects of vegetation fragmentation and mixed grazing (ie mono- or multi-species animal group) on the diet composition of sheep and red deer grazing mosaics of grassland and heather moorland was studied, using faecal cuticle analysis, in two experimental sites in Scotland during the summer of 1992 and 1993. On Site A, the influence of grassland fragmentation on diet composition was estimated for sheep and deer grazing together in plots where the grassland (20% of the area) was artificially distributed as one large, four medium or twelve small patches within a homogeneous moorland matrix (80% of the area). On Site B, differences in diet composition between animals grazing within mono-species (sheep or deer) and multi-species groups (sheep and deer together) were examined for each animal species. In this site all plots used contained a similar natural mosaic pattern of grass and heather (ie similar mixtures of patch sizes, with about 20% grass and 80% heather cover). On Site A, the proportions of grass in the diet of sheep (73%) and deer (27%) were found to be similar across all levels of grass fragmentation. A significant interaction was found between the pattern of fragmentation and the three periods in which the experiment was carried out. On Site B in 1992, sheep had more grass in their diet than did deer (52% vs 46%), and the diets of both sheep and deer responded in the same fashion when the species were grazing in mono- or multi-species groups, The consumption of grass decreased in both species throughout the period studied. Deer showed no change in the proportion of grass in their diet in the presence or absence of sheep in 1992 (deer 48% vs sheep 50%). But on Site B in 1993, the diet of sheep contained a significantly higher proportion of grasses when they were grazing with red deer (52%) than when they were grazing alone (38%). These results suggest that on grassland/heather moorland mosaics sheep may suffer intraspecies competition to a greater extent than do red deer, particularly where grass is in relatively low supply,
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