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1

Intra-specific variation and taxa- sampling affects the home range - body mass relationship

100%
Nilsen E. B., Linnell J. D. C.
Acta Theriologica
|
2006
|
tom 51
|
nr 3
225-232
The relationship between home range size and body mass is a frequently studied allometric relationship. However, the results of various studies differ greatly, leading to much debate about the nature of the relationship. We argue that this confusion is not surprising, due to intra-specific variation in home range size caused by ecological variability rather than by body mass. By random resampling of different studies from within 16 Carnivora species, we show that the scaling exponent ranged from 0.30–1.54 depending on the particular studies included for each species. Of these exponents, 10% did not contain 0.75 within their confidence limits, and 5.5% did not contain 1.00. Furthermore, by randomly sub-sampling 16 species from a total sample of 58 species, we found that the scaling exponent varied between 0.18 and 2.76. Of these exponents, 42.2% did not contain 0.75 within their confidence limits, whereas 16.8% did not contain 1.00. Therefore, we strongly recommend that greater consideration be paid to intra-specific ecological variability and taxa selection when dealing with both allometry and cross-species life history studies.
2

Territorial fidelity and tenure in roe deer bucks

100%
Linnell J. D. C., Andersen R.
Acta Theriologica
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1998
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tom 43
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nr 1
We present data on fidelity to territory, and length of tenure (multi-year) for bucks of European roe deer Capreolus capreolus (Linnaeus, 1758) based on 26 radio-collared individuals that were followed for up to 5 years. Individual bucks showed a high degree of fidelity to summer territory, with consecutive year's activity centres being less than 200 m apart on average. An average 70% of one year's territory was within the borders of the previous year's territory. No buck occupied a territory which did not overlap with the previous year's territory. Activity centres of consecutive winter home ranges were on average 502 m apart, although this difference was not sig­nificant. Several cases of switching between non-overlapping winter ranges between years were observed. Annual survival was high (97%) and we observed only a single case of an old buck losing dominance on his former territory after a very hard winter. All other surviving bucks regained their dominance on their territories. It is suggested that the roe deer bucks were demonstrating an "always stay" strategy in order to gain the benefits of site familiarity. This is in keeping with the concept of roe deer territoriality being a relatively "low-risk low-gain" strategy where emphasis is placed on survival and multi-year tenure of a territory.
3

Age-specific reproductive behaviours in male roe deer Capreolus capreolus

81%
Melis C., Hoem S. A., Linnell J. D. C., Andersen R.
Acta Theriologica
|
2005
|
tom 50
|
nr 4
445-452
The behaviour of active male roe deerCapreolus capreolus Linnaeus, 1758 was studied in a wild population on Storfosna island (Norway), during the pre-territorial and territorial seasons (February–August) of 1994. Observed behaviours were grouped in seven categories (mating, aggression, display, marking, vigilance, moving and maintenance), and the proportion of time spent in each behaviour by three age classes (yearlings, subadults and adults) was compared. Time spent in each behaviour varied significantly between months for all male age classes. From February to August, time spent in maintenance decreased, while time spent in vigilance increased. The time spent in mating increased both in adult and subadults but did not vary significantly for yearlings throughout the months. When comparing age classes within a month, there were no significant differences in time spent in each behaviour. Surprisingly, adult territorial males did not invest significantly more time in mating, with respect to yearlings and subadults. This may be consistent with the oligogynous mating system of roe deer, in which the reproductive success is divided amongst several years and their territoriality, which could be a tactic to reduce the competition for mating.
4

Selection of bed-sites by roe deer Capreolus capreolus fawns in an agricultural landscape

80%
Linnell J. D. C., Nilsen E. B., Andersen R.
Acta Theriologica
|
2004
|
tom 49
|
nr 1
The vegetation characteristics and habitat selection associated with the bed-sites used by neonatal roe deer Capreolus capreolus (Linnaeus, 1758) fawns were studied in an agricultural environment in central Norway. Data were collected from 85 radio- -collared fawns belonging to 38 families during 1992-1994. All bed-sites used provided effective cover, although this differed between habitats and increased during the summer as the herbaceous vegetation developed. Seasonal use of farmland increased and then decreased reflecting the growth, and cutting of the grass. Habitats were not used in relation to their availability. Early born fawns significantly avoided farmland, whereas later born fawns showed no significant selection or avoidance of any habitats. The data show how roe deer fawns are able to exploit small patches of non-cultivated habitats in an agricultural landscape.
5

Patterns of variation in reproductive parameters in Eurasian lynx (Lynx lynx)

71%
Nilsen E. B., Linnell J. D. C., Odden J., Samelius G., Andren H.
Acta Theriologica
|
2012
|
tom 57
|
nr 3
Detailed knowledge of the variation in demographic rates is central for our ability to understand the evolution of life history strategies and population dynamics, and to plan for the conservation of endangered species. We studied variation in reproductive output of 61 radio-collared Eurasian lynx females in four Scandinavian study sites spanning a total of 223 lynx-years. Specifically, we examined how the breeding proportion and litter size varied among study areas and age classes (2-year-old vs. >2-year-old females). In general, the breeding proportion varied between age classes and study sites, whereas we did not detect such variation in litter size. The lack of differences in litter sizes among age classes is at odds with most findings in large mammals, and we argue that this is because the level of prenatal investment is relatively low in felids compared to their substantial levels of postnatal care.
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