Roar Solheim

Roar Solheim
Natural History Museum, Agder University · Zoological Department

Doctor of Philosophy

About

81
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Publications

Publications (81)
Article
Full-text available
The global population and status of Snowy Owls Bubo scandiacus are particularly challenging to assess because individuals are irruptive and nomadic, and the breeding range is restricted to the remote circumpolar Arctic tundra. The International Union for Conservation of Nature (IUCN) uplisted the Snowy Owl to “Vulnerable” in 2017 because the sugges...
Technical Report
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The lemming cycle determines whether snowy owls breed or not, and in 2023 a lemming peak was expected. Only one nest of snowy owls was documented in Norway and Fennoscandia in 2023. The previous season with successful nesting snowy owls was in 2015. This year’s expected nesting season was largely spoiled when the lemming population collapsed due to...
Technical Report
Full-text available
The Snowy Owl project is a co-operation between the Norwegian Institute for Nature Research, Natural History Museum (University of Agder) and BirdLife Norway (former Norwegian Ornithological Society). In 2021 the project initiated a collaboration with postdoc Helle Tessand Baalsrud at Norwegian University of Life Sciences (NMBU). Her project covers...
Article
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Highly mobile predators can show strong numerical responses to pulsed resources, sometimes resulting in irruptions where large numbers of young invade landscapes at a continental scale. High production of young in irruption years may have a strong influence on the population dynamics unless immature survival is reduced compared to non-irruption yea...
Chapter
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Owls in county East-Agder, southern Norway (in Norwegian)
Technical Report
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Extended description of molt patterns and aging of Snowy Owls, including molt interpretations of photos of wings of Snowy owls captured for banding in US and Canada.
Article
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Four breeding Ural Owls (Strix uralensis) (one pair, one female and one male) were radio-tagged at the nest and tracked on foot with portable equipment in Hedmark county in SE Nor-way. The owls´ positions were determined by cross-triangulating or by direct observations. A total of 105 plotted locations were obtained. The mated male and female were...
Conference Paper
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ABSTRACT In July 2007 we collected a total of 309 Snowy Owl (Bubo scandiacus) pellets from 35 vantage points in an area where we located four Snowy Owl territories in northern Norway. The number of pellets found at each vantage point ranged from 1 to 39 (mean: 8.8, median: 6, SD + 1.8). While the four nests were situated 513, 522, 524 and 529 m asl...
Article
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Investigating space use of wild birds provides important knowledge of bird behavior and ecology, which is crucial in the management and conservation of threatened species. In the present study, we used GPS satellite telemetry to investigate space use and movements of seven adult Eurasian Eagle-Owls (Bubo bubo) in Norway during breeding and post-bre...
Article
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Photographies can be used to identify and recognize individuals of butterflies with distinct marks on their wings, here illustrated with a study on apollo (Parnassius apollo) and poplar admiral (Limenitis populi) butterflies. Taking digital photos of the butterflies may render capturing and tagging unnecessary when studying small and isolated popul...
Article
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Article
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The mechanisms behind expansions of the distribution of a bird species and the ensuing establishment of new populations are poorly known. The distribution of Great Grey Owl (Strix nebulosa) in the western Palearctic has generally expanded towards southwest during the past fifty years, and particularly so in Fennoscandia. In the past decade, the rec...
Article
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Migratory species display a range of migration patterns between irruptive (facultative) to regular (obligate), as a response to different predictability of resources. In the Arctic, snow directly influences resource availability. The causes and consequences of different migration patterns of migratory species as a response to the snow conditions re...
Book
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PhD-dissertation: Abstract The world is heating up. The climate is changing, with increasing temperature changes towards the Arctic. Northern ecosystems of tundra and taiga are subject to changes, even in the most remote areas void of human presence. One of the most profound characteristics of these northern ecosystems are the cyclic changes in po...
Article
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В 2007, 2011 и 2915 гг. мы пометили спутниковыми передатчиками ARGOS, работающими на аккумуляторах, 9 белых сов в Норвегии. Целью исследования было выявление районов зимовки и отслеживание зимних перемещений белых сов, гнездящихся на севере Фенноскандии. Получены данные общей сложностью для 21 «индивидуального» периода зимовки; каждый их 9 передатч...
Poster
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During breeding years in 2007, 2011 and 2015 we recorded four, 42 and 24 nests or nesting attempts of Snowy Owls in Northern Norway. Based on photos of flying owls and collected molt feathers we found two females in 2011 and one female in 2015 that bred as one year old (2CY).
Article
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The use of tracking devices to monitor birds is extensive, but the effects of such instruments on equipped individuals are still insufficiently taken into account. Here we evaluate potential effects of backpack-mounted satellite transmitters (platform terminal transmitters; PTTs) on survival of 28 Snowy Owls Bubo scandiacus. Six confirmed deaths we...
Article
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Bar patterns on flight feathers of Great Gray Owls (Strix nebulosa) and Snowy Owls (Bubo scandiacus) are variable, and can be used to recognize individual birds. Here I illustrate a method for taking photos of wings of captured owls and describe a way to arrange images of flying birds for comparison with photos of birds in flight or in the hand. I...
Article
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3073 Great Grey Owls were banded in Sweden in 1955–2012. 416 were controlled at least once (54.6%) or recovered dead (45.4%).Three birds banded as nestlings were recovered in their 17th calendar year. Most birds were recovered during first year of life. Only 4 females were controlled breeding as 2CY birds. 91.3% of birds controlled as first time br...
Article
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Genetic analysis has shown to be an important and efficient method for monitoring species, but the lack of genetic markers constrains such monitoring for many species. Here, we cross-amplified microsatellite loci in the snowy owl (Bubo scandiacus) using primers previously characterized in other species. Among polymorphic loci, we selected 12 loci t...
Article
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Record breaking numbers of breeding Great Grey Owls Strix nebulosa were reported in Sweden and Norway in 2010 and 2011, followed by 4105 observations in 2012 as revealed by the national Species archives. Based on locality id numbers, at least 144 individuals were reported with photos which could be used to age the individuals. The majority (76%) of...
Article
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The distribution of the Ural Owl (Strix uralensis) in Europe shrank dramatically at the end of the nineteenth century, largely through direct persecution. No genetic information on this species is available that could provide a basis for ongoing conservation and breeding programs. Here, we genetically analyzed wild and captive populations of Europe...
Technical Report
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Snøugla har en sirkumpolar utbredelse. Hekkeområdene er i stor grad knyttet til treløs tundra og høyfjellsområder i Fennoskandia, Russland, Alaska, Canada og Grønland. I Norge hekket snøugla tidligere regelmessig fra Finnmark og sørover til Dovrefjell og Hardangervidda. Mye tyder på at tilbakegangen, i alle fall i Sør-Norge, startet allerede på beg...
Article
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Blackflies (Simuliidae) have been shown to influence birds negatively in several ways. In 2011, during a peak lemming year, we found that two of 28 nests of Snowy Owls Bubo scandiacus in Northern Norway and Finland failed due to blackfly attacks on the incubating female. The observations also suggest that adult survival may be influenced by these i...
Article
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Abstract. Moult of primary and secondary flight feathers of Snowy Owls Bubo scandiacus was studied from 53 museum specimens retaining some juvenile feathers. There were no ringed Snowy Owls of known age in the skin material, and the moult pattern has thus been interpreted using the moult of Eagle Owls Bubo bubo as a model. The difference between ju...
Article
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The harvest mouse (Micromys minutus) occurs throughout most of continental Europe. There are also two isolated and recently discovered populations on the Scandinavian peninsula, in Sweden and Norway. Here, we investigate the origin of these populations through analyses of mitochondrial DNA. We found that the two populations on the Scandinavian peni...
Article
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Moult of primaries and secondaries of Scandinavian Eagle Owls Bubo bubo was studied from 42 museum specimens of which the birds’age was known. During their second year they moult the three innermost secondaries (S 13-15). The following summer the moult of secondaries progresses outwards. Primary P7 is moulted, and in many birds also P6 and P8. Duri...
Article
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From January to May 2006, 130 Tawny Owls were reported dead along the coastal areas of southern Norway. Of these, 79 were collected for a museum collection, most from the counties Vest-Agder (27), Aust-Agder (37), Telemark (9) and Vestfold (4). One owl was found starving, and was nurtured back to life. Of 67 sexable specimens, there were 34 males a...
Article
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Great Grey Owls start flight feather moult when in their second year. Moult was studied on outspread wings of 58 individuals in the collections at Naturhistoriska Riksmuseet in Stockholm. The owls always moulted the innermost secondaries in their first moult, and usually at least two primaries, most often P5 and P6. After this moult, birds had 11–1...
Article
We investigated the distributions and routes of colonization of two commensal subspecies of house mouse in Norway: Mus musculus domesticus and M. m. musculus. Five nuclear markers (Abpa, D11 cenB2, Btk, SMCY and Zfy2) and a morphological feature (tail length) were used to differentiate the two subspecies and assess their distributions, and mitochon...
Article
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The Ural Owl Strix uralensis meets its westernmost distribution in Hedmark County, southeast Norway. Since 1979 we have provided the species with nest boxes in this region. A total of 80 nest boxes were put out in prime Ural Owl habitat, starting with 9 in 1979, 18 in 1982 and 53 in 1985. Two more nest boxes put up by others, and four made by ourse...
Article
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The snowy owl (Bubo scandiacus) is a nomadic species with a circumpolar distribution. It has recently declined in the western Palearctic and may thus be worthy of special consideration for conservation. We investigated genetic structure in three well separated geographic regions within the snowy owls’ breeding range. We sequenced two mitochondrial...
Article
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Article
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Crosses between male black grouse Tetrao tetrix and female capercaillie T. urogallus are the most common grouse hybrids. Some male hybrids (F1-generation) may be fertile and produce offspring (F2-generation) with females of capercaillie and, rarely, black grouse. Specimens and descriptions of lek behaviour are also available for probable F3- and F3...
Article
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Among Tengmalm's owls ringed in Norway, natal and female breeding dispersal distances were longer if dispersal took place during a microtine prey population low than if dispersal occurred within a microtine peak. Of the recorded cases of female breeding dispersal, 13% could be termed nomadic (dispersal distance >100 km). Female and overall natal di...
Article
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Pygmy owls preferred nestboxes with entrance holes <55 mm for caching, while nestboxes with larger holes were primarily used as sheltered feeding sites. Caching took place from October-April, with a peak in November-January. Single caches contained up to 97 prey items, and regular surplus killing by individual pygmy owls may explain the sudden fill...
Article
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Eleven nests were located in the boreal zone, the remaining 18 in the boreonemoral zone. Clutch sizes varied from 3-10 eggs. Onset of breeding lasted from the end of march to the middle of May. In the boreonemoral zone breeding took place both in years of high and low vole abundance, while in the boreal zone successful breedings were only recorded...
Article
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Six cases of bigyny and four of biandry in Tengmalm's Owl published up to and including 1981 are reviewed. There were no differences between the number of eggs layed by primary and secondary females of bigynous males, but a higher mortality of the young was found among secondary broods. This is probably linked with the females' dependence on male f...
Article
Full-text available
There were no differences between the number of eggs layed by primary and secondary females of bigynous males, but a higher mortality of the young was found among secondary broods. This is probably linked with the females' dependence on male food support during breeding. Among primary and secondary clutches of biandrous females no differences in re...

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