排序方式: 共有51条查询结果,搜索用时 15 毫秒
31.
Geir A. Sonerud Henning Hansen Christian A. Smedshaug 《Behavioral ecology and sociobiology》2002,51(4):309-318
The function of the conspicuous pre-roost gathering in communally roosting birds is poorly known. We studied movement and
social cohesion of radio-tagged hooded crows (Corvus corone cornix) from their daytime location via pre-roost to roost in autumn and winter. With increasing snowfall the previous 24 h, the
crows attended pre-roosts farther from the territory, and moved longer from pre-roost to roost. The crows became more likely
to roost communally as distance to their territory increased. Attending a pre-roost on average almost doubled the travel distance
to a communal roost. Crows were much more likely to join the same roost when they had attended the same pre-roost than otherwise.
Breeding mates were more likely to keep together from pre-roost to roost than were other assigned pairs of a territorial male
and female. For assigned pairs of non-mates, cohesion from pre-roost to roost decreased with increasing distance to roost,
and was higher when both crows roosted communally compared to when at least one of them roosted in its territory. When both
roosted communally, cohesion decreased with increasing snowfall and increasing number of crows attending the pre-roost, increased
with increasing snow depth, and became higher among two females, compared to other combinations of two crows, with increasing
number of crows attending the pre-roost. These patterns may be interpreted as supporting several of the current hypotheses
on the function of pre-roost gathering.
Electronic Publication 相似文献
32.
Paal DM Levin JO Ostin A Rosenberg C Henriks-Eckerman ML Brødsgaard S Thorud SH Fladseth G Thomassen Y 《Journal of environmental monitoring : JEM》2002,4(5):685-687
The Nordic Network on Isocyanates (NORDNI) is financed by the Nordic Council of Ministers and is under the administration of Prof. Yngvar Thomassen and co-workers. National Institute of Occupational Health, Norway. The aim of NORDNI is to establish a broad network between the Nordic National Institutes of Occupational Health working within the field of isocyanate exposure and strategies for sampling and determination of isocyanates in workroom atmospheres. This viewpoint article summarizes the resolutions that were established at the 1st NORDNI consensus meeting arranged in Fr?ya, Norway, 31st August-2nd September, 2001. The consensus platform from the 1st NORDNI meeting was presented at the 4th International Symposium on Modern Principles of Air Monitoring, Lillehammer, Norway, 3-7 February, 2002. 相似文献
33.
Pusch K Schlabach M Prinzinger R Wing Gabrielsen G 《Journal of environmental monitoring : JEM》2005,7(6):635-639
A wide range and occasionally high levels of persistent organic pollutants (POPs) are reported in Arctic regions, especially among top predators. Polar bears (Ursus maritimus), arctic foxes (Alopex lagopus) and some gull species (Larus spp.) often have high levels of these fat-soluble pollutants. Gulls deposit significant levels of these contaminants in their eggs. In northern regions, gull eggs are part of the traditional human diet. In the present study we have investigated the levels of POPs in gull eggs in order to determine the tolerable weekly intake (TWI) for humans. Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in 214 gull eggs collected in the spring of 2001-02. The eggs were collected from four gull species (herring gulls (Larus argentatus), great black-backed gulls (L. marinus), lesser black-backed gulls (L. fuscus) and glaucous gulls (L. hyperboreus)) at 12 different locations in Northern Norway, on the Faroe Islands and on Svalbard. The pollutant levels in gull eggs were found to be 65.5 +/- 26.9 pg toxic equivalent (TE) for dioxin and PCB g(-1) wet weight. Based on these findings and the TWI-value determined by the EU Scientific Committee on Food it is advised that children, young women and pregnant and nursing women should not eat gull eggs. Other people should limit their intake of eggs to an absolute minimum, considering the health risks associated with gull egg intake. 相似文献
34.
Louise C. Ross Gunnar Austrheim Leif-Jarle Asheim Gunnar Bjarnason Jon Feilberg Anna Maria Fosaa Alison J. Hester Øystein Holand Ingibjörg S. Jónsdóttir Lis E. Mortensen Atle Mysterud Erla Olsen Anders Skonhoft James D. M. Speed Geir Steinheim Des B. A. Thompson Anna Gudrún Thórhallsdóttir 《Ambio》2016,45(5):551-566
35.
Tobias Dittmann Peter H. Becker Joop Bakker Anders Bignert Elisabeth Nyberg M. Glória Pereira Ursula Pijanowska Richard F. Shore Eric Stienen Geir Olav Toft Harald Marencic 《Environmental science and pollution research international》2012,19(9):4060-4072
To categorize the marine environmental health status, the Oslo and Paris commissions have recently formulated Ecological Quality Objectives (EcoQOs) for many ecological features including the contamination of coastal bird eggs with mercury and organochlorines. In this study, we describe spatial and temporal patterns of egg contamination around the North Sea and compared them to the EcoQOs. Concentrations of mercury, polychlorinated biphenyl (??PCB) congeners, dichlorodiphenyltrichloroethane (??DDT) and derivatives, hexachlorobenzene (HCB) and hexachlorocyclohexane (??HCH) isomers were analysed in two tern species (Sterna hirundo and Sterna paradisaea) and Oystercatcher (Haematopus ostralegus) eggs collected between 2008 and 2010 in a total of 21 sites in seven countries surrounding the North Sea. Hg, ??PCB and HCB were highest in the southern sites, while ??DDT and ??HCH concentrations were greatest in eggs from the western North Sea and the Elbe estuary. There were rarely any consistent decreases over time for any compounds. In the terns, Hg, HCB and ??HCH increased at most sites, ??PCB and ??DDT in Sweden and Norway. In the Oystercatcher, HCB and ??HCH increased at more than the half of the sites, ??PCB, ??DDT and Hg at several German sites. In the terns, Hg, ??PCB and ??DDT exceeded the EcoQO in all, HCB in most years and sites. At most sites, ??HCH fulfilled the EcoQO in some study years. In the Oystercatcher, Hg, ??PCB and ??DDT exceeded the EcoQO in all or most years and sites. HCB and ??HCH fulfilled the EcoQO in some or all years at most sites. The EcoQO was exceeded most frequently in estuaries. We conclude that EcoQOs are suitable for drawing contamination patterns of the coastal North Sea in an easily understandable manner, offering the opportunity to harmonize the EcoQOs with coordinated environmental monitoring programmes. 相似文献
36.
Environmental pollutants in the Swedish marine ecosystem, with special emphasis on polybrominated diphenyl ethers (PBDE) 总被引:1,自引:0,他引:1
Levels of polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and perfluorinated organic compounds (PFCs) were analysed in whole herring (Clupea harengus) and sprat (Sprattus sprattus), eggs from common eider (Somateria mollissima) and eggs and livers from herring gull (Larus argentatus) from the Swedish west coast. The contaminant values obtained were compared with published values from the Arctic marine ecosystem. Tetra- and penta-brominated PBDEs were detected at low levels in herring, sprat and common eider (ΣPBDE 0.3-2.0 ng g−1 ww), while the levels were higher in the herring gull samples (ΣPBDE 1.3-29.9 ng g−1 ww). Hexa-decaBDEs were also found in samples from herring gulls. Eggs from herring gulls from the sub-Arctic contained four times more PBDE than the Swedish herring gulls eggs. Fish samples from the Arctic had two times higher levels of PBDEs and DDTs than similar samples from Sweden. The higher levels of contaminants in fish and seabirds from the Arctic reflect differences in transport processes, feeding ecology (reflected by trophic levels) and metabolism. PBDEs contributed to <10% of the total contaminant load in all investigated samples. The relative contribution of DDTs was higher in fish and bird samples from the Arctic when compared to Swedish samples, e.g. 65% in glaucous gull livers compared to 10% in herring gull livers. This study shows that even though the Swedish west coast is more urban than the Arctic, higher pollutants levels are found in seabird species from the Arctic. 相似文献
37.
Knudsen LB Borgå K Jørgensen EH van Bavel B Schlabach M Verreault J Gabrielsen GW 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):25-33
The northern fulmar (Fulmarus glacialis) is an interesting candidate for the study of patterns and levels of halogenated organic contaminants (HOCs) since they accumulate high levels of certain HOCs. In the present study we characterized a suite of established and novel HOCs in northern fulmars breeding on Bj?rn?ya in the Norwegian Arctic. A comparison between blood and liver HOC levels was made, and the levels were related to the ratios of heavier to lighter stable isotopes of nitrogen (15)N/(14)N (delta(15)N) and carbon (13)C/(12)C (delta(13)C) in muscle. A significant difference in congener patterns between blood and liver was found. The delta(13)C was not related to HOCs, neither in liver nor in blood. Weak correlations were found between delta(15)N and liver HOC levels. The 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) in northern fulmars were well above thresholds for reproductive effects in seabirds. 相似文献
38.
Bioaccumulation of per- and polyfluorinated alkyl substances (PFAS) in selected species from the Barents Sea food web 总被引:2,自引:0,他引:2
Haukås M Berger U Hop H Gulliksen B Gabrielsen GW 《Environmental pollution (Barking, Essex : 1987)》2007,148(1):360-371
The present study reports concentrations and biomagnification potential of per- and polyfluorinated alkyl substances (PFAS) in species from the Barents Sea food web. The examined species included sea ice amphipod (Gammarus wilkitzkii), polar cod (Boreogadus saida), black guillemot (Cepphus grylle) and glaucous gull (Larus hyperboreus). These were analyzed for PFAS, polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs) and polybrominated diphenyl ethers (PBDEs). Perfluorooctane sulfonate (PFOS) was the predominant of the detected PFAS. Trophic levels and food web transfer of PFAS were determined using stable nitrogen isotopes (delta(15)N). No correlation was found between PFOS concentrations and trophic level within species. However, a non-linear relationship was established when the entire food web was analyzed. Biomagnification factors displayed values >1 for perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), PFOS and SigmaPFAS(7). Multivariate analyses showed that the degree of trophic transfer of PFAS is similar to that of PCB, DDT and PBDE, despite their accumulation through different pathways. 相似文献
39.
Levels and temporal trends (1983-2003) of persistent organic pollutants (POPs) and mercury (Hg) in seabird eggs from Northern Norway 总被引:1,自引:0,他引:1
Helgason LB Barrett R Lie E Polder A Skaare JU Gabrielsen GW 《Environmental pollution (Barking, Essex : 1987)》2008,155(1):190-198
The main objective of this study was to investigate possible temporal trends of persistent organic pollutants (POPs) and mercury in eggs of herring gulls (Larus argentatus), black-legged kittiwakes (Rissa tridactyla), common guillemots (Uria aalge) and Atlantic puffins (Fratercula arctica) in Northern Norway. Eggs were collected in 1983, 1993 and 2003. Egg concentrations of POPs (PCB congeners IUPAC numbers: CB-28, 74, 66, 101, 99, 110, 149, 118, 153, 105, 141, 138, 187, 128, 156, 157, 180, 170, 194, 206, HCB, alpha-HCH, beta-HCH, gamma-HCH, oxychlordane, trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT) and mercury were quantified. Generally, POP levels decreased between 1983 and 2003 in all species. No significant temporal trend in mercury levels was found between 1983 and 2003. 相似文献
40.
Verreault J Bech C Letcher RJ Ropstad E Dahl E Gabrielsen GW 《Environmental pollution (Barking, Essex : 1987)》2007,145(1):138-145
Exposure to organohalogens in endotherms has been suggested to impose chemically induced stress by affecting functions related to maintenance energy requirements. Effects on basal metabolic rate (BMR) have been suggested to be, in part, mediated through interactions with the thyroid hormones (THs). We investigated the relationships between plasma concentrations of major organochlorines, PBDEs, hydroxylated (OH)- and methoxylated (MeO)-PBDEs and OH-PCBs, circulating TH levels and BMR in breeding glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Negative associations were found between BMR and concentrations of sigma PCB, Sigma DDT and particularly Sigma chlordane, which combined made up 91% of the total contaminant burden. Levels of THs (thyroxine and triiodothyronine) were not associated significantly with variation of BMR or concentrations of any of the compounds determined. The present study suggests that BMR may be altered in glaucous gulls exposed to high loadings of persistent contaminants in the Norwegian Arctic environment. 相似文献