| 1. |
- Antoniou, Antonis C., et al.
(författare)
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A locus on 19p13 modifies risk of breast cancer in BRCA1 mutation carriers and is associated with hormone receptor-negative breast cancer in the general population
- 2010
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 42:10, s. 885-892
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Tidskriftsartikel (refereegranskat)abstract
- Germline BRCA1 mutations predispose to breast cancer. To identify genetic modifiers of this risk, we performed a genome-wide association study in 1,193 individuals with BRCA1 mutations who were diagnosed with invasive breast cancer under age 40 and 1,190 BRCA1 carriers without breast cancer diagnosis over age 35. We took forward 96 SNPs for replication in another 5,986 BRCA1 carriers (2,974 individuals with breast cancer and 3,012 unaffected individuals). Five SNPs on 19p13 were associated with breast cancer risk (P-trend = 2.3 x 10(-9) to Ptrend = 3.9 x 10(-7)), two of which showed independent associations (rs8170, hazard ratio (HR) = 1.26, 95% CI 1.17-1.35; rs2363956 HR = 0.84, 95% CI 0.80-0.89). Genotyping these SNPs in 6,800 population-based breast cancer cases and 6,613 controls identified a similar association with estrogen receptor-negative breast cancer (rs2363956 per-allele odds ratio (OR) = 0.83, 95% CI 0.75-0.92, P-trend = 0.0003) and an association with estrogen receptor-positive disease in the opposite direction (OR = 1.07, 95% CI 1.01-1.14, P-trend = 0.016). The five SNPs were also associated with triple-negative breast cancer in a separate study of 2,301 triple-negative cases and 3,949 controls (Ptrend = 1 x 10(-7) to Ptrend = 8 x 10(-5); rs2363956 per-allele OR = 0.80, 95% CI 0.74-0.87, P-trend = 1.1 x 10(-7)).
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| 2. |
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| 3. |
- Alwall Svennefelt, Catharina, et al.
(författare)
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Förebyggande av arbetsskador inom lantbruket : "Säkert Bondförnuft" ur ett lantbrukarperspektiv
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Arbetsolycksfall är en stor kostnad och medför stora problem för såväl samhälle, företag och individer. En av de mest utsatta branscherna är lantbruket i Sverige, såväl i många andra delar av världen där sektorn har likartade problem. Finansiering via EU:s landsbygdsprogram gav möjligheter att jobba förebyggande i en stor landsomfattande satsning ”Säkert Bondförnuft” som administreras av Lantbrukarnas riksförbund (LRF) och som genomförts i samarbete med Institutet för jordbruks- och miljöteknik (JTI) samt Sveriges lantbruksuniversitet (SLU) . På uppdrag av LRF har en utvärdering av satsningen Säkert Bondförnuft gjorts avseende det första verksamhetsåret 2010. I uppdraget ingick att särskilt utvärdera lantbrukarnas perspektiv vad gäller de två huvudaktiviteterna a) Kursen Tre träffar till Säkert Bondförnuft och b) Individuellt gårdsbesök. Utvärderingen genomfördes i form av telefonintervjuer med lantbrukare som deltagit i Säkert Bondförnufts aktiviter samt en kontrollgrupp som inte deltagit. Resultaten visade bl a att de tillfrågade lantbrukarna var i mycket hög omfattning nöjda med sitt deltagande i Säkert Bondförnufts aktiviteter. Resultaten indikerade att något fler kursdeltagarna var nöjda i relation till de som haft ett Individuellt gårdsbesök. Vidare framkom att lantbrukare som haft gårdsbesök i mycket hög grad (>90%) vidtagit åtgärder för att förbättra arbetsmiljön på sin gård. även de som deltagit i kursen Tre träffartill Säkert Bondförnuft har genomfört många åtgärder. Kontrollgruppen rapporterade att knappt 20 % gjort arbetsmiljöförbättringar. Det framgick också av intervjusvaren att sex av tio lantbrukare upplevde att arbetsmiljö och säkerhet blev viktigare efter att man deltagit i Säkert Bondförnufts olika aktiviteter. En stor andel av lantbrukarna upplevde att man efter deltagandet i Säkert Bondförnufts aktiviteter fått tillräckliga kunskaper för att de själva eller tillsammans med andra på gården skulle kunna fortsätta bedriva systematiskt arbetsmiljöarbete och/eller andra arbetsmiljöförbättrande åtgärder. I de fall då man inte upplevde att man hade tillräckliga kunskaper efterlyste man mer rådgivning på gårdsnivå, ytterligare arbetsmiljöutbildning, bättre rådgivningsmaterial samt praktisk träning av färdigheter t ex gällande användning av motorsåg, fyrhjulingar, djurhantering samt stresshantering. Lantbrukarna som intervjuades fick även svara på korta frågor kring deras attityder till risker och säkerhetsfrågor i lantbruket. Kontrollgruppen fick samma frågor som de som deltagit i Säkert Bondförnufts aktiviteter. De allra flesta är överens om att investeringar i säkerhet lönar sig – något mer övertygade var de som deltagit i Säkert Bondförnufts aktiviteter. På frågan om det ingår i lantbrukaryrket att utsätta sig för risker fanns en stor spridning bland de olika grupperna. Att få säkerheten regelbundet kontrollerad på gården var kursdeltagarna mycket övertygade om, även de som haft gårdsbesök tyckte detta var viktigt. De som deltog i Landjas undersökning (före Säkert Bondförnufts uppstart) hade inte alls samma inställning till detta. Att man tummar på säkerheten ibland var en något vanligare uppfattning i kontrollgruppen och att man var mer medveten om riskerna för olycksfall jämfört med andra lantbrukare var en klart vanligare uppfattning bland dem som haft Individuellt gårdsbesök än de som deltagit i kursen. Slutligen var de som deltagit i kursen Tre träffar till Säkert Bondförnuft mer övertygade om vikten av att ha en krisplan jämfört med andra lantbrukares uppfattning. Detta var en ettårig uppföljning av satsningen Säkert Bondförnuft och det är viktigt att göra förnyade uppföljningar, dels av samma lantbrukare, för att se om det blir långsiktiga effekter av insatserna och dels följa upp nya grupper av lantbrukare som deltagare som tagit del av aktiviteter som genomförts 2011 och 2012. Detta är en unik satsning som det är synnerligen viktigt att fortsätta utvärdera. Resultaten tyder på att satsningen Säkert Bondförnuft är en viktig satsning som bör fortsätta efter utgång av nuvarande verksamhetsperiod 2013.
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| 4. |
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| 5. |
- Heldbjerg, Henning, et al.
(författare)
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Contrasting population trends of common starlings (Sturnus vulgaris) across Europe
- 2019
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Ingår i: Ornis Fennica. - 0030-5685. ; 96:4, s. 153-168
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Tidskriftsartikel (refereegranskat)abstract
- The greatest loss of biodiversity in the EU has occurred on agricultural land. The Common Starling (Sturnus vulgaris) is one of the many numerous and widespread European farmland breeding bird species showing major population declines linked to European agricultural intensification. Here we present results based on monitoring data collected since 1975 in 24 countries to examine the influence of changing extent of grassland and cattle abundance (based on results of earlier studies showing the importance of lowland cattle grazed grassland for the species), wintering provenance and temperature on national breeding population trends of Starlings across Europe. Positive Starling population trends in Central-East Europe contrast with negative trends in North and West Europe. Based on this indicative approach, we found some support for the importance of cattle stock and no support for grassland, temperature or wintering provenance to explain Starling population trends in Europe. However, we acknowledge such a European-wide analysis may conceal regional differences in responses and suggest that currently accessible national land use data might be insufficient to describe the detailed current changes in animal husbandry and grassland management that may be responsible for changes in food availability and hence breeding Starling abundance and their differences across Europe. Reviewing results from local studies relating Starling population trends to local agricultural change offer contradictory results, suggesting complex interacting processes at work. We recommend combining national datasets on demography, land-use/agricultural practices and from autecological research to better explain the reasons for contrasting Starling trends across Europe, to enable us to predict how changing agriculture will affect Starlings and potentially suggest mitigation measures to restore local populations where possible.
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| 6. |
- Kudenchuk, Peter J, et al.
(författare)
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Breakthrough in cardiac arrest: reports from the 4th Paris International Conference.
- 2015
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Ingår i: Annals of Intensive Care. - : Springer Science and Business Media LLC. - 2110-5820. ; 5:1, s. 22-22
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Forskningsöversikt (refereegranskat)abstract
- Jean-Luc Diehl The French Intensive Care Society organized on 5th and 6th June 2014 its 4th "Paris International Conference in Intensive Care", whose principle is to bring together the best international experts on a hot topic in critical care medicine. The 2014 theme was "Breakthrough in cardiac arrest", with many high-quality updates on epidemiology, public health data, pre-hospital and in-ICU cares. The present review includes short summaries of the major presentations, classified into six main chapters: Epidemiology of CA Pre-hospital management Post-resuscitation management: targeted temperature management Post-resuscitation management: optimizing organ perfusion and metabolic parameters Neurological assessment of brain damages Public healthcare.
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| 7. |
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| 8. |
- Mumme, Steffen, et al.
(författare)
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Wherever I may roam—Human activity alters movements of red deer (Cervus elaphus) and elk (Cervus canadensis) across two continents
- 2023
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Ingår i: Global Change Biology. - Chichester : Wiley-Blackwell Publishing Inc.. - 1354-1013 .- 1365-2486. ; 29:20, s. 5788-5801
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Tidskriftsartikel (refereegranskat)abstract
- Human activity and associated landscape modifications alter the movements of animals with consequences for populations and ecosystems worldwide. Species performing long-distance movements are thought to be particularly sensitive to human impact. Despite the increasing anthropogenic pressure, it remains challenging to understand and predict animals' responses to human activity. Here we address this knowledge gap using 1206 Global Positioning System movement trajectories of 815 individuals from 14 red deer (Cervus elaphus) and 14 elk (Cervus canadensis) populations spanning wide environmental gradients, namely the latitudinal range from the Alps to Scandinavia in Europe, and the Greater Yellowstone Ecosystem in North America. We measured individual-level movements relative to the environmental context, or movement expression, using the standardized metric Intensity of Use, reflecting both the directionality and extent of movements. We expected movement expression to be affected by resource (Normalized Difference Vegetation Index, NDVI) predictability and topography, but those factors to be superseded by human impact. Red deer and elk movement expression varied along a continuum, from highly segmented trajectories over relatively small areas (high intensity of use), to directed transitions through restricted corridors (low intensity of use). Human activity (Human Footprint Index, HFI) was the strongest driver of movement expression, with a steep increase in Intensity of Use as HFI increased, but only until a threshold was reached. After exceeding this level of impact, the Intensity of Use remained unchanged. These results indicate the overall sensitivity of Cervus movement expression to human activity and suggest a limitation of plastic responses under high human pressure, despite the species also occurring in human-dominated landscapes. Our work represents the first comparison of metric-based movement expression across widely distributed populations of a deer genus, contributing to the understanding and prediction of animals' responses to human activity. Global Change Biology© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.
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| 9. |
- Nolan, Jerry P, et al.
(författare)
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Intensive care medicine research agenda on cardiac arrest
- 2017
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Ingår i: Intensive Care Medicine. - : Springer Science and Business Media LLC. - 0342-4642 .- 1432-1238. ; 43:9, s. 1282-1293
-
Tidskriftsartikel (refereegranskat)abstract
- Over the last 15 years, treatment of comatose post-cardiac arrest patients has evolved to include therapeutic strategies such as urgent coronary angiography with percutaneous coronary intervention (PCI), targeted temperature management (TTM)—requiring mechanical ventilation and sedation—and more sophisticated and cautious prognostication. In 2015, collaboration between the European Resuscitation Council (ERC) and the European Society for Intensive Care Medicine (ESICM) resulted in the first European guidelines on post-resuscitation care. This review addresses the major recent advances in the treatment of cardiac arrest, recent trials that have challenged current practice and the remaining areas of uncertainty.
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| 10. |
- Osorio, Ana, et al.
(författare)
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DNA Glycosylases Involved in Base Excision Repair May Be Associated with Cancer Risk in BRCA1 and BRCA2 Mutation Carriers.
- 2014
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Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Single Nucleotide Polymorphisms (SNPs) in genes involved in the DNA Base Excision Repair (BER) pathway could be associated with cancer risk in carriers of mutations in the high-penetrance susceptibility genes BRCA1 and BRCA2, given the relation of synthetic lethality that exists between one of the components of the BER pathway, PARP1 (poly ADP ribose polymerase), and both BRCA1 and BRCA2. In the present study, we have performed a comprehensive analysis of 18 genes involved in BER using a tagging SNP approach in a large series of BRCA1 and BRCA2 mutation carriers. 144 SNPs were analyzed in a two stage study involving 23,463 carriers from the CIMBA consortium (the Consortium of Investigators of Modifiers of BRCA1 and BRCA2). Eleven SNPs showed evidence of association with breast and/or ovarian cancer at p<0.05 in the combined analysis. Four of the five genes for which strongest evidence of association was observed were DNA glycosylases. The strongest evidence was for rs1466785 in the NEIL2 (endonuclease VIII-like 2) gene (HR: 1.09, 95% CI (1.03-1.16), p = 2.7×10-3) for association with breast cancer risk in BRCA2 mutation carriers, and rs2304277 in the OGG1 (8-guanine DNA glycosylase) gene, with ovarian cancer risk in BRCA1 mutation carriers (HR: 1.12 95%CI: 1.03-1.21, p = 4.8×10-3). DNA glycosylases involved in the first steps of the BER pathway may be associated with cancer risk in BRCA1/2 mutation carriers and should be more comprehensively studied.
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| 11. |
- Persson Sunde, Erik, et al.
(författare)
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The physical state of water in bacterial spores.
- 2009
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Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 106:46, s. 19334-19339
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Tidskriftsartikel (refereegranskat)abstract
- The bacterial spore, the hardiest known life form, can survive in a metabolically dormant state for many years and can withstand high temperatures, radiation, and toxic chemicals. The molecular basis of spore dormancy and resistance is not understood, but the physical state of water in the different spore compartments is thought to play a key role. To characterize this water in situ, we recorded the water 2H and 17O spin relaxation rates in D2O-exchanged Bacillus subtilis spores over a wide frequency range. The data indicate high water mobility throughout the spore, comparable with binary protein–water systems at similar hydration levels. Even in the dense core, the average water rotational correlation time is only 50 ps. Spore dormancy therefore cannot be explained by glass-like quenching of molecular diffusion but may be linked to dehydration-induced conformational changes in key enzymes. The data demonstrate that most spore proteins are rotationally immobilized, which may contribute to heat resistance by preventing heat-denatured proteins from aggregating irreversibly. We also find that the water permeability of the inner membrane is at least 2 orders of magnitude lower than for model membranes, consistent with the reported high degree of lipid immobilization in this membrane and with its proposed role in spore resistance to chemicals that damage DNA. The quantitative results reported here on water mobility and transport provide important clues about the mechanism of spore dormancy and resistance, with relevance to food preservation, disease prevention, and astrobiology.
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| 12. |
- Peters, Wibke, et al.
(författare)
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Large herbivore migration plasticity along environmental gradients in Europe : life-history traits modulate forage effects
- 2018
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Ingår i: Oikos. - Chichester : Wiley-Blackwell Publishing Inc.. - 0030-1299 .- 1600-0706. ; 128, s. 416-429
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Tidskriftsartikel (refereegranskat)abstract
- The most common framework under which ungulate migration is studied predicts that it is driven by spatio–temporal variation in plant phenology, yet other hypotheses may explain differences within and between species. To disentangle more complex patterns than those based on single species/ single populations, we quantified migration variability using two sympatric ungulate species differing in their foraging strategy, mating system and physiological constraints due to body size. We related observed variation to a set of hypotheses. We used GPS-collar data from 537 individuals in 10 roe Capreolus capreolus and 12 red deer Cervus elaphus populations spanning environmental gradients across Europe to assess variation in migration propensity, distance and timing. Using time-to-event models, we explored how the probability of migration varied in relation to sex, landscape (e.g. topography, forest cover) and temporally-varying environmental factors (e.g. plant green-up, snow cover). Migration propensity varied across study areas. Red deer were, on average, three times more migratory than roe deer (56% versus 18%). This relationship was mainly driven by red deer males which were twice as migratory as females (82% versus 38%). The probability of roe deer migration was similar between sexes. Roe deer (both sexes) migrated earliest in spring. While territorial male roe deer migrated last in autumn, male and female red deer migrated around the same time in autumn, likely due to their polygynous mating system. Plant productivity determined the onset of spring migration in both species, but if plant productivity on winter ranges was sufficiently high, roe deer were less likely to leave. In autumn, migration coincided with reduced plant productivity for both species. This relationship was stronger for red deer. Our results confirm that ungulate migration is influenced by plant phenology, but in a novel way, that these effects appear to be modulated by species-specific traits, especially mating strategies. © 2018 The Authors. Oikos © 2018 Nordic Society Oikos
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| 13. |
- Sunde, Peter, et al.
(författare)
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A telemetry study of the social organization of a tawny owl (Strix aluco) population
- 2004
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Ingår i: Journal of Zoology. - 0952-8369. ; 263:1, s. 65-76
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Tidskriftsartikel (refereegranskat)abstract
- The spatial dispersion and social interactions were studied in I I neighbouring pairs of radio-tagged tawny owls Strix aluco in a deciduous wood in Denmark from 1998-2001. The numbers and shapes of territories were stable throughout the survey and similar to a mapping made 40 years earlier. The home ranges of mates were of equal size and overlapped 82% in summer and 56% in winter. The inter-mate distances were on average 2.7% shorter than expected by chance. The activity distribution of neighbouring pairs overlapped 9% (95% CI: 2-15%) on average. Males and females did not differ in overlap with neighbours, and there was a similar overlap between neighbours of the same and opposite sex. Both sexes vocalized more often in the peripheries than in the centres of their territory. The vocal activity during May-September varied extensively among years and months in accordance with variation in the density of juvenile floaters. Males and females vocalized equally often and were involved in disputes with neighbours at similar rates. Usually, neighbouring disputes involved either one individual from each pair or all four. Disputes involving all four owls more often involved chasing and fighting than those involving one owl only from each pair. The dispute rate between neighbouring pairs correlated positively with home-range overlap. The total annual mortality was 21% (95% CI: 6-33%). Dead owners were usually replaced within 1 2 months. Two out of four cases of radio-tagged owls disappearing from their territory because of natural causes was due to take-overs by invading owls, suggesting that the risk of losing fitness resulting from eviction was important. The apparent co-operative territorial behaviour of tawny owl pairs is probably due to improved resource holding potential of pair coalitions compared to single individuals.
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| 14. |
- Sunde, Peter, et al.
(författare)
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Combining information from range use and habitat selection: sex-specific spatial responses to habitat fragmentation in tawny owls Strix aluco
- 2006
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Ingår i: Ecography. - : Wiley. - 1600-0587 .- 0906-7590. ; 29:2, s. 152-158
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Tidskriftsartikel (refereegranskat)abstract
- How individuals respond to habitat heterogeneity is usually measured as variation in range size and by ranking the relative importance of habitat types (habitat selection). The combined effect of how individuals incorporate different habitat types in their home ranges and allocate their time budget between them is rarely derived. Additionally, when home range size varies between individuals, habitat selection analyses might be flawed if foraging decisions are based on variation in absolute rather than proportional availability. We investigated the suitability of standard analytical approaches by measuring the spatial responses of tawny owls to habitat fragmentation. These owls inhabited woodland of various sizes, representing a fragmentation gradient from open farmland with small, isolated woodland patches, to continuous woodland within their home ranges. In 17 territories within open farmland, the available area covered by woodland increased with the square root of the area of open land embraced in the home range. The owls did not display functional response in habitat selection, but females selected woodland more strongly than males. Females utilised woodland 10 times more intensively in farmland than in continuous woods, whereas males utilised farmland woods 3.2 times more intensively. Moreover, females in farmland exploited woodland 3.2 times as intensively as males, apparently because of higher travel costs in open areas. Since the extensive variation in intensity of use as a function of total availability was not indicated from the analysis of habitat selection, we suggest that information about intensity of use be more widely used as a supplementary measure of habitat use patterns than appears to be the practice at present.
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| 15. |
- Sunde, Peter, et al.
(författare)
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Diurnal exposure as a risk sensitive behaviour in tawny owls Strix aluco?
- 2003
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Ingår i: Journal of Avian Biology. - : Wiley. - 0908-8857 .- 1600-048X. ; 34:4, s. 409-418
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Tidskriftsartikel (refereegranskat)abstract
- Tawny owls Strix aluco generally roost in cryptic locations during the day. To test the hypothesis that this cryptic behaviour is an effort to avoid mobbers or avian predators, we measured diurnal behaviour and cause-specific mortality of radio-tagged birds. Non-breeding adults (assumed to be well fed individuals, optimising their own survival) roosted in less exposed locations than adults with young and newly independent juveniles. Parents roosted in the most exposed sites when their young were immature and vulnerable to depredation, probably to guard offspring. Newly independent juveniles apparently selected roosting sites in exposed places to get access to food, as this behaviour was associated with lower perching heights and higher prey abundance beneath their roosting sites. They also perched in more exposed sites, closer to the ground, in summers with low prey abundance compared to summers with high prey abundance. After previous encounters with goshawks Accipiter gentilis, dependent juveniles roosted in less exposed places compared to other young. The increased risk of being mobbed was highly significant with increasing roosting exposure. Once an owl was mobbed, the intensity of the mobbing correlated positively with the mass of the mobbers, but mobbing birds never killed any owls. In contrast, diurnal raptors caused 73% of natural owl deaths (n = 15) and the depredation rate by raptors was 3.8 times higher in population classes that generally roosted in more exposed locations than did non-breeding adults. We therefore suggest that depredation by diurnal raptors is the main factor shaping the diurnal behaviour of tawny owls.
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| 16. |
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| 17. |
- Sunde, Peter
(författare)
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Predators control post-fledging mortality in tawny owls, Strix aluco
- 2005
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Ingår i: Oikos. - : Wiley. - 1600-0706 .- 0030-1299. ; 110:3, s. 461-472
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Tidskriftsartikel (refereegranskat)abstract
- Despite its recognition as an important source of variation in recruitment probability, the ecological processes leading to mortality between fledging and independence are poorly studied. Accordingly, the proximate and ultimate impact of bottom-up (food limitation) and top-down factors (predators, pathogens) for individual survival as well as population productivity is largely unknown in most terrestrial birds. Survival and behaviour of 131 radio-tagged tawny owls (Strix aluco) during the post-fledging dependency period were studied for each of three years with high food abundance and three years of poor food supply in Danish deciduous woods. To identify the effects of food limitation, 32 young received extra food 2-3 weeks prior to fledging, as opposed to 99 young that were fed by their parents only. Thirty-six percent of the young from control broods died between fledging and independence, primarily due to predation from raptors and mammals (predominantly foxes Vulpes vulpes). Predation by mammals occurred within the first few days after fledging, with young leaving the nest at an early age being at particularly high risk. Young that had received extra food as nestlings were also at higher risk of being preyed upon by mammals, possibly because they were easier to locate on their smell. Total mortality risk (control broods) increased with fledging date from 14% in April to > 58% in June due to an increasing raptor predation risk. Individual attributes such as sex, condition, immunocompetence or prevalence of blood parasites did not predict total or cause-specific mortality risk. Survival during the post-fledging dependency period was therefore primarily a function of variation in predation pressures, particularly from raptors. Increasing raptor predation of late broods appears to be an important selective agent for early breeding in the tawny owl.
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| 18. |
- Sunde, Peter, et al.
(författare)
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Reversed sexual dimorphism in tawny owls, Strix aluco, correlates with duty division in breeding effort
- 2003
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Ingår i: Oikos. - : Wiley. - 1600-0706 .- 0030-1299. ; 101:2, s. 265-278
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Tidskriftsartikel (refereegranskat)abstract
- Even though most bird species with a raptorial feeding habit express varying extents of reversed sexual dimorphism (RSD: females bigger than males), the evolutionary basis for its maintenance, as well as its possible secondary consequences for the ecological adaptations of the different sexes, is debated. We studied pairs of tawny owls, Strix aluco (females 20% heavier than males), throughout the year by telemetry to test whether any inter-sexual differences in movement patterns, resource partitioning and breeding effort correlated with RSD. Females were larger than males in all body size measures and were 16% heavier than would be expected from the difference in wing length alone. In accordance with predictions from flight economics, males moved longer distances per time unit than females, in particular during the post-fledging season, when they also fed chicks more often than the females. Males had larger home ranges than females during the post-fledging period, whereas the sexes had home ranges of equal size during the non-breeding season. Until 10 days after fledging, females foraged much closer to the offspring than males, apparently balancing their distance to offspring between the needs of offspring guarding and foraging. In males, the parent-offspring distance only increased with decreasing brood condition. The sexes did not differ in habitat use or feeding habits, rendering no indications of food niche partitioning. The study provides further evidence that selection for males to be light and energetically efficient foragers is the main evolutionary force behind RSD in raptorial birds, even when the prey base is confined by territoriality.
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| 19. |
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