Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2007
Forfattere
Atle Mysterud Erling Meisingset Vebjørn Veiberg Rolf Langvatn Erling Johan Solberg Leif Egil Loe Nils Christian StensethSammendrag
Proper management of wildlife relies on metrics of population development. Typically, the best estimation techniques are too expensive for coarse-scale management. In marine fisheries, catch-per-unit effort is commonly used, but problems may arise due to changes in spatial harvest effort or in habitat use as density changes. Managers in Norway are in the early phases of implementing "seen deer" during harvesting and "spring counts" on farmland as a means of monitoring red deer Cervus elaphus populations. We provide a first evaluation of how suitable these methods are by comparing the results with population estimates obtained using cohort analysis, and by analysing the within-season variation in number of seen deer. "Seen deer" predicted annual increases in populations fairly well. Adjusting for harvesting effort provided less good estimates, due to a proportionally larger increase in effort relative to deer population size as population size increased. The number of seen deer per day decreased rapidly at the beginning of the season, and then levelled off or increased slightly during the rut, especially on farmland. The number of seen deer increased both with the number of harvesters and hours harvested, but at a diminishing rate. The current practice of "spring counts" was not successful in predicting population changes, probably due to a lack of replication. Indeed, date strongly affected the number of deer seen during spring counts. While "seen deer" seems to be a very promising tool for monitoring population size of red deer, there are some limitations to the practice as implemented for moose Alces alces in Scandinavia due to a more complex relationship with harvesting effort. Our study highlights that the large number of hours harvesters observe wildlife can provide a useful tool for population monitoring. However, the use of such indices may vary between species and according to harvest techniques and should thus be assessed with care before implementation
Forfattere
Inger HansenSammendrag
De mest effektive forebyggende tiltak er de som skiller rovvilt og beitedyr i tid og rom. Dette innebærer driftstilpasninger i områder hvor det skal være faste forekomster av rovvilt.
Forfattere
Inger HansenSammendrag
Orientering om de mest effektive forebyggende tiltakene for å redusere tap av sau til rovvilt.
Sammendrag
In summer, more than 2.1 million sheep and lamb graze in Norwegian outfield and mountain ranges. Up to the 1990ties, the losses of sheep and lambs were stable, with an annual loss of approx. 3,6 %, mainly due to accidents, illnesses and carnivores. The numbers of large carnivores (wolf, bear, lynx and wolverine) and the golden eagle has increased the last 15-20 years, due to international agreements and a political will in Norway to have sustainable populations of these species. At the same time, the annual losses of sheep and lambs has increased to a peak last year (2006) of 6,8 %. Reindeer has had the same development regarding increased depredation. The paper deals with present and future R&D in causes of loss and preventive measures, and information and advice to farmers and authorities on methods to prevent depredation. The main goal is to reduce the losses of sheep and reindeer, and at the same time reach the government"s goal on sustainable population of carnivores. In 2006, Bioforsk launched a website which summarize the knowledge of causes of losses and preventive methods on depredation, based on an agricultural approach and Biofosk"s competence in animal welfare, grazing and livestock management.
Forfattere
Inger HansenSammendrag
Tapsårsaker hos lam i Ørpen-Redalen beiteområde, Krødsherad 2007. Kartlagt vhja. mortalitetssendere (dødsvarslere). Foreløpige resultater.
Forfattere
Inger HansenSammendrag
Tapsårsaker hos lam på utmarksbeite i Rode 1, Saltdal kommune 2007, ved bruk av mortalitetssendere (dødsvarslere). Foreløpige resultater.
Forfattere
Inger HansenSammendrag
Om antipredatoratferd hos ulike saueraser. Leserinnlegg etter fjernsynsreportasje i Schrödingers katt.
Forfattere
Inger HansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Inger HansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Inger HansenSammendrag
Orientering om standardene (fastsatt av DN) for de mest effektive forebyggende tiltak mot tap av sau til rovvilt.