Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2013
Sammendrag
The mating system ofCapercaillie has been referred to as “exploded lek” because displaying males are spaced farther apart than on classical leks. However, inter-male distances and spacing behavior rarely have been quantified. In 2009–2011, we examined the spatial relationships of males on two leks in southeastern Norway by GPS satellite telemetry. Largely exclusive display territories (median 2 ha) surrounded the mating site, but the males spent most of the time displaying on smaller, well-defined display sites (median 182 m2) within their territories. When on their display sites, neighboring birds were spaced 64–212 m apart; decreasing to a minimum during the time of mating. Occasionally, males made long exploratory excursions (median 243 m) across the territories of neighbors, sometimes interacting with them at close distance (< 10m). During daytime, males resided solitarily in radially extending ranges within 1 km of the lek center, commuting to the lek either in the evening or morning by walking or flying, leaving in the morning mostly by walking. The distance from the lek center to night roosting trees and daytime resting areas decreased during the mating season. With interacting males and a spatial arrangement in-between that of classical leks and dispersed polygyny, the term “exploded lek” seems appropriate for the mating system of Capercaillie.
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Forfattere
Ghislain Tchoromi Tepa-Yotto Trond Hofsvang May SæthreSammendrag
No abstract has been registered
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Theo RuissenSammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
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Ingebjørg Helena Nymo Morten Tryland Anne Kirstine Højholt Frie Tore Haug Geoffrey Foster Rolf Rødven Jacques GodfroidSammendrag
No abstract has been registered
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Paula Marie Bräunlich Ole Andreas Løchen Økstad Rune Slimestad Helle Wangensteen Karl Egil Malterud Hilde BarsettSammendrag
No abstract has been registered
Forfattere
Liv Østrem Birger Volden Arild LarsenSammendrag
The potential of ×Festulolium as a forage species for Nordic conditions was investigated by comparing Norwegian candivars (LpFp-T, LmFp-T, LpFp-D-N, LpFp-D-UK) differing in parental origin and ploidy level with commercial cultivars of ×Festulolium (Hykor, Felopa), the parental species perennial ryegrass (Lolium perenne L.) and meadow fescue (Festuca pratensis L.), and timothy (Phleum pratense L.). Plant development was observed as leaf:stem ratio and standardised development stage, and dry matter yield and digestibility were studied throughout two consecutive harvest seasons (2007 and 2008) as an effect of taking the first cut at four maturity stages, namely: 1) vegetative growth, 2) early heading), 3) heading and 4) anthesis, and then consecutive cuts throughout the season. Observations were made at two locations in Norway (61°N, 67°N). Leaf:stem ratio and standardised development stage were affected by maturity stage, and the loloid types of ×Festulolium (Felopa and the candivars) grouped between the parental species as to developmental pattern. The most extreme changes across maturity stages 1-4 in first cut were seen in the festucoid type Hykor (smallest) and in timothy (largest). Across maturity stages 2 and 3, for two years Hykor obtained higher dry matter yield than the other entries, but overall digestible dry matter yield was equal in Hykor and LpFp-T due to the better digestibility in LpFp-T. The lower dry matter yield obtained in ×Festulolium Felopa, the diploid candivars and LmFp-T was mainly due to winter damages. Consistency was found between the locations for the entries investigated. For Nordic growing conditions, in which winter hardiness is required for commercial cultivars, the amphitetraploid breeding approach of perennial ryegrass and meadow fescue should be pursued. It is the parental origin of the candivar LpFp-T, which was comparable to Hykor, the best of the commercial ×Festulolium cultivars, and performed better than the cultivars of the parental species.
Sammendrag
No abstract has been registered