Institutt for natur, helse og miljø: Nye registreringer
Viser treff 301-320 av 321
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Subspecies discrimination in the Scandinavian beaver (Castor fiber): combining behavioral and chemical evidence
(Journal article; Peer reviewed, 2004)Geographic isolation is one of several models that has been proposed to explain the evolutionary course of speciation. In this study, we examined how geographical isolation may affect subspecies discrimination in the ... -
The beaver's reconquest of Eurasia: status, population development, and management of a conservation success
(Journal article; Peer reviewed, 2002)Overhunting reduced Eurasian Beaver (Castor fiber) populations to c. 1200 animals, in eight isolated populations, around the end of the 19th century. Protection, natural spread and reintroductions led to a powerful recovery ... -
Scent-marking in the Eurasian beaver (Castor fiber) as a means of territory defense
(Journal article; Peer reviewed, 1998)Beaver (Castor spp.) normally scent mark by depositing castoreum and/or anal gland secretion on scent mounds close to the water's edge. The aim of this study was to investigate the hypothesis that the Eurasian beaver (C. ... -
Selective foraging on woody plant species by the Eurasian beaver (Castor fiber) in Telemark, Norway
(Journal article; Peer reviewed, 2006)Beavers Castor spp. are generalist herbivores, feeding on the bark, shoots and leaves of woody plants, terrestrial herbs and forbs, ferns and aquatic vegetation. As central-place foragers, beavers move out from water to ... -
Use of space and movement patterns in monogamous adult Eurasian beavers (Castor fiber)
(Journal article; Peer reviewed, 2004)Monogamy in mammals is characterized by reduced sexual dimorphism in morphology and behaviour. Ten pairs of Eurasian beaver Castor fiber were radio-tracked to test how far this concept can be applied to movement behaviour ... -
Responses of foraging Eurasian beavers Castor fiber to predator odours
(Journal article; Peer reviewed, 2000)The ability of Eurasian beavers Castor fiber to recognise different predator odours has received little research, nor has the use of predator odours to deter Eurasian beavers from damaging agricultural crops, fruit and ... -
Field anaesthetic and surgical techniques for implantation of intraperitoneal radio transmitters in Eurasian beavers Castor fiber
(Journal article; Peer reviewed, 2004)Radio transmitters were implanted intraperitoneally in 22 (nine females, 13 males) adult, territorial Eurasian beavers Castor fiber under field conditions. Two different injectable anaesthestic drug combinations were tested. ... -
Methods for live-trapping beaver (Castor spp.)
(Journal article; Peer reviewed, 1998)Effective live-trapping of beaver (Castor spp.) has been and will continue to be necessary for introductions, re-introductions, translocation for the preservation of populations, removal of nuisance beaver, and to obtain ... -
Investigations of waterborne pathogens in Eurasian beaver (Castor fiber) from Telemark county, Southeast Norway
(Journal article; Peer reviewed, 2001)The presence of pathogenic bacteria and parasites in drinking water is a well-known cause of human disease outbreaks. There is however, a lack of knowledge of the contamination routes to water. In Norway, the supply of ... -
Eurasian beavers (Castor fiber) behavioral response to simulated territorial intruders
(Journal article; Peer reviewed, 2000)Eurasian beavers (Castor fiber) live in family groups that defend territories against other conspecifics. Part of this territorial defence involves constructing scent mounds near the stream bank within territories and ... -
Parturition dates for Eurasian beavers Castor fiber: when should spring hunting cease?
(Journal article; Peer reviewed, 2001)Hunting Eurasian beaver Castor fiber with firearms during late spring is the dominating harvest form in Norway but may violate the Norwegian wildlife management principle of not hunting during the breeding season. In ... -
Odorant source used in Eurasian beaver territory marking
(Journal article; Peer reviewed, 2001)Mammals use urine, feces, or the secretion of specialized skin glands to mark their territories. These sources can carry different information and, thus, have different functions. Presently it is not known if beavers (Castor ... -
Landscape use and economic value of Eurasian beaver (Castor fiber) on large forest in southeast Norway
(Conference report, 1999)Though numerous studies of damage caused by beaver (Castor canadensis and C. fiber) to commercially managed forests have been conducted, few have incorporated the economic advantages beaver can create for forest owners. ... -
Factors affecting scent-marking behavior in Eurasian beaver (Castor fiber)
(Journal article; Peer reviewed, 1997)We tested the hypothesis that a main function of territory marking in Eurasian beaver (Castor fiber) is defense of the territory. The results showed that. (1) beaver colonies with close neighbors scent-mark more often than ... -
Errors associated with moose-hunter counts of occupied beaver Castor fiber lodges in Norway
(Journal article; Peer reviewed, 2002)In Norway, Sweden and Finland moose Alces alces hunting teams are often employed to survey occupied beaver (Castor fiber and C. canadensis) lodges while hunting. Results may be used to estimate population density or trend, ... -
Comeback of the beaver Castor fiber : an overview of old and new conservation problems
(Journal article; Peer reviewed, 1998)Due to over-hunting c. 1200 Eurasian previous termbeaversnext term Castor fiber survived in eight relict populations in Europe and Asia at the beginning of the 20th century. Following hunting restrictions and translocation ... -
Effectiveness of predator odors as gray squirrel repellents
(Journal article; Peer reviewed, 2001)The ability of gray squirrels (Sciurus carolinensis) to discriminate between different predator odors and the use of predator odors to deter gray squirrels from foraging on plants have not been previously investigated. To ... -
A test of the dear enemy phenomenon in the Eurasian beaver
(Journal article; Peer reviewed, 2002)We tested the hypothesis that Eurasian beavers, Castor fiber, display the dear enemy phenomenon; that is, they respond less aggressively to intrusions by their territorial neighbours than intrusions by nonterritorial ... -
Cadmium, copper, and zinc in Eurasian beaver (Castor fiber) from Bø, Telemark, Norway
(Journal article; Peer reviewed, 2001)Heavy metals are elements present in all forms of life. Of those analysed for in the present study, cadmium (Cd) is toxic and non-essential while copper (Cu) and zinc (Zn) are essential elements, but toxic when certain ... -
Can beaver Castor fiber be selectively harvested by sex and age during spring hunting?
(Conference report, 2000)In Norway, Sweden and Finland hunting Eurasian beaver Castor fiber Linnaeus, 1758 with firearms is presently the main harvest form and most are shot in late April and early May. As beaver cannot be sexed from external ...