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The sites of 87 brown bear Ursus arctos Linnaeus, 1758 attacks on livestock (horses, cattle, sheep, goats) were investigated in the Cantabrian Mountains, Spain. Ninety percent of livestock predation occurred between May and October, while attacks were most frequent during the months of May and July. There was no difference in overall attack rates between the first and second part of the year, nor among livestock type or age-class. Bears were not selective predators of livestock type or age-class, but had a slight tendency to attack more cattle and adult animals. Bear tracks and scats were found at slightly more than half of the sites visited, while bed construction and food-caching behaviour was rarely detected. Attacks were initiated most times on the neck and the head region. Muscle tissue and soft organs were most preferred body parts consumed by brown bears.
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.
Evidence of non-hibernation in brown bears Ursus arctos Linnaeus, 1758 on the Iberian Peninsula has existed since the Middle Ages. We systematically monitored brown bears in the Cantabrian Mountains (Northern Spain) by recording tracks and sightings from 1998 to 2007 to document hibernation behaviour. Our results indicate that females with yearlings and solitary yearlings were more active in winter than bears over two years old. Intensive snow tracking and direct observations of five family groups indicated that they travelled, fed and defecated in winter, which are activities not compatible with the physiological state of hibernation. Also, based on tracking data, the maximum period between two consecutive locations of active family groups in winter was less than that needed by bears to emerge from a state of hibernation (6 days). We conclude that the family groups which we monitored in winter did not hibernate.
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.
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.
Two species of Lower Devonian rugose corals are described from the Cantabrian Mountains of Spain: Cantabriastraea cantabrica gen. et sp. nov. and Tabulophyllum bonarense sp. nov. The development of rootor buffer−like attachment structures (“rhizoid processes”) in T. bonarense indicates adaption to the soft substrate and supports corallite stabilisation. Because of their strongly everted calices and a corresponding arrangement of trabeculae, the colonies of the genus Cantabriastraea are assigned tentatively to the Paradisphyllinae, constituting the first record of the subfamily in Western Europe. Some specimens give information on colony−formation of this taxon, which is induced by strong lateral budding (nonparricidal increase) of a remarkable large and long−lasting protocorallite.
Two different assemblages of skeletonized microfossils are recorded in bioclastic shoals that cross the Lower–Middle Cambrian boundary in the Esla nappe, Cantabrian Mountains. The uppermost Lower Cambrian sedimentary rocks represent a ramp with ooid−bioclastic shoals that allowed development of protected archaeocyathan−microbial reefs. The shoals yield abundant debris of tube−shelled microfossils, such as hyoliths and hyolithelminths (Torellella), and trilobites. The overlying erosive unconformity marks the disappearance of archaeocyaths and the Iberian Lower–Middle Cambrian boundary. A different assemblage occurs in the overlying glauconitic limestone associated with development of widespread low−relief bioclastic shoals. Their lowermost part is rich in hyoliths, hexactinellid, and heteractinid sponge spicules (Eiffelia), chancelloriid sclerites (at least six form species of Allonnia, Archiasterella, and Chancelloria), cambroclaves (Parazhijinites), probable eoconchariids (Cantabria labyrinthica gen. et sp. nov.), sclerites of uncertain affinity (Holoplicatella margarita gen. et sp. nov.), echinoderm ossicles and trilobites. Although both bioclastic shoal complexes represent similar high−energy conditions, the unconformity at the Lower–Middle Cambrian boundary marks a drastic replacement of microfossil assemblages. This change may represent a real community replacement from hyolithelminth−phosphatic tubular shells to CES (chancelloriid−echinoderm−sponge) meadows. This replacement coincides with the immigration event based on trilobites previously reported across the boundary, although the partial information available from originally carbonate skeletons is also affected by taphonomic bias.
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