Wyniki wyszukiwania

1

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

100%

Nilsen E. B., Linnell J. D. C.

Acta Theriologica

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2006

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tom 51

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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.

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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

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2004

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tom 49

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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.

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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

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2012

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tom 57

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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.

Ograniczanie wyników

3 Acta Theriologica

3 Linnell J. D. C.

3 Nilsen E. B.

1 Andersen R.

1 Andren H.

1 Odden J.

1 Samelius G.

1 2012

1 2006

1 2004

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

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

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