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The 1988 and 2002 phocine distemper virus epidemics in European harbour seals.

https://arctichealth.org/en/permalink/ahliterature6586
Source
Dis Aquat Organ. 2006 Jan 30;68(2):115-30
Publication Type
Article
Date
Jan-30-2006
Author
Tero Härkönen
Rune Dietz
Peter Reijnders
Jonas Teilmann
Karin Harding
Ailsa Hall
Sophie Brasseur
Ursula Siebert
Simon J Goodman
Paul D Jepson
Thomas Dau Rasmussen
Paul Thompson
Author Affiliation
Swedish Museum of Natural History, Box 50007, 10405 Stockholm, Sweden. tero.harkonen@swipnet.se
Source
Dis Aquat Organ. 2006 Jan 30;68(2):115-30
Date
Jan-30-2006
Language
English
Publication Type
Article
Keywords
Age Factors
Animals
Carnivora
Comparative Study
Disease Outbreaks - veterinary
Disease Reservoirs - veterinary
Disease Vectors
Distemper - epidemiology - mortality - pathology
Distemper Virus, Phocine
Environmental Exposure - adverse effects
Europe - epidemiology
Female
Male
Morbillivirus - classification - pathogenicity
Phoca - virology
Research Support, Non-U.S. Gov't
Sex Factors
Time Factors
Abstract
We present new and revised data for the phocine distemper virus (PDV) epidemics that resulted in the deaths of more than 23 000 harbour seals Phoca vitulina in 1988 and 30,000 in 2002. On both occasions the epidemics started at the Danish island of Anholt in central Kattegat, and subsequently spread to adjacent colonies in a stepwise fashion. However, this pattern was not maintained throughout the epidemics and new centres of infection appeared far from infected populations on some occasions: in 1988 early positive cases were observed in the Irish Sea, and in 2002 the epidemic appeared in the Dutch Wadden Sea, 6 wk after the initiation of the outbreak at Anholt Island. Since the harbour seal is a rather sedentary species, such 'jumps' in the spread among colonies suggest that another vector species could have been involved. We discussed the role of sympatric species as disease vectors, and suggested that grey seal populations could act as reservoirs for PDV if infection rates in sympatric species are lower than in harbour seals. Alternatively, grey seals could act as subclinical infected carriers of the virus between Arctic and North Sea seal populations. Mixed colonies of grey and harbour seal colonies are found at all locations where the jumps occurred. It seems likely that grey seals, which show long-distance movements, contributed to the spread among regions. The harbour seal populations along the Norwegian coast and in the Baltic escaped both epidemics, which could be due either to genetic differences among harbour seal populations or to immunity. Catastrophic events such as repeated epidemics should be accounted for in future models and management strategies of wildlife populations.
PubMed ID
16532603 View in PubMed
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Accumulation and potential health effects of organohalogenated compounds in the arctic fox (Vulpes lagopus)-a review.

https://arctichealth.org/en/permalink/ahliterature257066
Source
Sci Total Environ. 2014 Oct 6;502C:510-516
Publication Type
Article
Date
Oct-6-2014
Author
Kathrine Eggers Pedersen
Bjarne Styrishave
Christian Sonne
Rune Dietz
Bjørn Munro Jenssen
Author Affiliation
Toxicology Laboratory, Section of Advanced Drug Analysis, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark. Electronic address: hct186@alumni.ku.dk.
Source
Sci Total Environ. 2014 Oct 6;502C:510-516
Date
Oct-6-2014
Language
English
Publication Type
Article
Abstract
This review addresses biological effects of anthropogenic organohalogenated compounds in the arctic fox (Vulpes lagopus). When considering the current levels, spatial and tissue distributions of selected organic pollutants in arctic fox subpopulations, especially the Svalbard based populations accumulate high levels. The dominating contaminant groups are the polychlorinated biphenyls (PCBs) and chlordanes (CHLs), which reach high levels in adipose tissues, adrenals and liver. Recent controlled exposure studies on domesticated arctic fox and Greenland sledge dogs, show adverse health effects associated with OC concentrations lower than those measured in free-ranging populations. This indicates that especially populations at Svalbard may be at risk of experiencing OC related effects. The arctic fox as such may be an overlooked species in the Arctic Monitoring and Assessment Programs and it would add further information about pollution in the Arctic to include this species in the monitoring program.
PubMed ID
25300015 View in PubMed
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Age and seasonal variation in testis and baculum morphology in East Greenland polar bears (Ursus maritimus) in relation to high concentrations of persistent organic pollutants.

https://arctichealth.org/en/permalink/ahliterature299071
Source
Environ Res. 2019 Mar 20; 173:246-254
Publication Type
Journal Article
Date
Mar-20-2019
Author
Ellinor Spörndly-Nees
Lena Holm
Floris M van Beest
Azadeh Fakhrzadeh
Elisabeth Ekstedt
Robert Letcher
Ulf Magnusson
Jean-Pierre Desforges
Rune Dietz
Christian Sonne
Author Affiliation
Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Box 7011, 75007, Sweden. Electronic address: Ellinor.Sporndly-Nees@slu.se.
Source
Environ Res. 2019 Mar 20; 173:246-254
Date
Mar-20-2019
Language
English
Publication Type
Journal Article
Abstract
Persistent organic pollutants (POPs) are found in high concentrations in the Artic. Polar bears (Ursus maritimus) are one of the most exposed mammals in the Arctic and are thereby vulnerable to reproductive disruption. The aim of this study was to investigate male polar bear reproduction based on a detailed evaluation of testis histology and to assess possible effects of environmental chemicals on male polar bear reproduction. Reproductive groups that were identified based on histology were as follows: actively reproductive (REP), non-reproductive either with degenerated testes (DEG), undeveloped seminiferous tubules (UND), or morphology in-transition (INT). Categorization into these groups was supported by significant differences in testis and baculum measurements among REP, DEG, and UND, as well as differences in the area and diameter of seminiferous tubules among REP, DEG, and UND. These results show that it is possible to identify the reproductive stage in polar bears even if capture date and or age is lacking. Based on testis morphology we suggest that adult male polar bears from East Greenland have active spermatogenesis in February to June, and inactive degenerated testes in August to January. January to February was the main period of reproductive transition, characterised by a shift between inactive and active spermatogenesis. Baculum and testis size measurements decreased significantly with increasing concentrations of the chlordane metabolite oxychlordane, suggesting a potential impact on male reproductive success. Half of the investigated polar bears in REP group displayed signs of disorganization of the spermatogenesis which might be a sign of disrupted reproduction. However, no correlations with levels of the investigated POPs were detected. Reproductive organ measurements in polar bears differed significantly between REP and DEG groups, which cannot be explained by age, and therefore should be considered when investigating the effect of POPs on male reproduction.
PubMed ID
30928855 View in PubMed
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Allee effect in polar bears: a potential consequence of polychlorinated biphenyl contamination.

https://arctichealth.org/en/permalink/ahliterature277927
Source
Proc Biol Sci. 2016 Nov 30;283(1843)
Publication Type
Article
Date
Nov-30-2016
Author
Viola Pavlova
Jacob Nabe-Nielsen
Rune Dietz
Christian Sonne
Volker Grimm
Source
Proc Biol Sci. 2016 Nov 30;283(1843)
Date
Nov-30-2016
Language
English
Publication Type
Article
Abstract
Polar bears (Ursus maritimus) from East Greenland and Svalbard exhibited very high concentrations of polychlorinated biphenyls (PCBs) in the 1980s and 1990s. In Svalbard, slow population growth during that period was suspected to be linked to PCB contamination. In this case study, we explored how PCBs could have impacted polar bear population growth and/or male reproductive success in Svalbard during the mid-1990s by reducing the fertility of contaminated males. A dose-response relationship linking the effects of PCBs to male polar bear fertility was extrapolated from studies of the effects of PCBs on sperm quality in rodents. Based on this relationship, an individual-based model of bear interactions during the breeding season predicted fertilization success under alternative assumptions regarding male-male competition for females. Contamination reduced pregnancy rates by decreasing the availability of fertile males, thus triggering a mate-finding Allee effect, particularly when male-male competition for females was limited or when infertile males were able to compete with fertile males for females. Comparisons of our model predictions on age-dependent reproductive success of males with published empirical observations revealed that the low representation of 10-14-year-old males among breeding males documented in Svalbard in mid-1990s could have resulted from PCB contamination. We conclude that contamination-related male infertility may lead to a reduction in population growth via an Allee effect. The magnitude of the effect is largely dependent on the population-specific mating system. In eco-toxicological risk assessments, appropriate consideration should therefore be given to negative effects of contaminants on male fertility and male mating behaviour.
PubMed ID
27903868 View in PubMed
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Alterations in thyroid hormone status in Greenland sledge dogs exposed to whale blubber contaminated with organohalogen compounds.

https://arctichealth.org/en/permalink/ahliterature100348
Source
Ecotoxicol Environ Saf. 2011 Jan;74(1):157-63
Publication Type
Article
Date
Jan-2011
Author
Maja Kirkegaard
Christian Sonne
Rune Dietz
Robert J Letcher
Asger L Jensen
Signe Stige Hansen
Bjørn Munro Jenssen
Philippe Grandjean
Author Affiliation
Department of Environmental Medicine, Institute of Public Health, University of Southern Denmark, J.B.Winsløvsvej 17, DK-5000 Odense, Denmark. majakirkegaard@yahoo.dk
Source
Ecotoxicol Environ Saf. 2011 Jan;74(1):157-63
Date
Jan-2011
Language
English
Publication Type
Article
Abstract
As a model of high trophic level carnivores, sledge dogs were fed from 2 to 18 months of age with minke whale blubber containing organohalogen compounds (OHC) corresponding to 128 µg PCB/day. Controls were fed uncontaminated porcine fat. Thyroid hormone levels were assessed in 7 exposed and 7 control sister bitches (sampled at age 6-18 months) and 4 exposed and 4 control pups, fed the same diet as their mothers (sampled age 3-12 months). Lower free and total T3 and T4 were seen in exposed vs. control bitches beyond 10 months of age, and total T3 was lower through 3-12 months of age in exposed pups. A negative correlation with thyroid gland weight was significant for SDDT, as was a positive association with total T3 for dieldrin. This study therefore supports observational data that OHCs may adversely affect thyroid functions, and it suggests that OHC exposure duration of 10 months or more may be required for current OHC contamination levels to result in detectable adverse effects on thyroid hormone dynamics.
PubMed ID
20888641 View in PubMed
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Analysis of narwhal tusks reveals lifelong feeding ecology and mercury exposure.

https://arctichealth.org/en/permalink/ahliterature307653
Source
Curr Biol. 2021 Mar 05; :
Publication Type
Journal Article
Date
Mar-05-2021
Author
Rune Dietz
Jean-Pierre Desforges
Frank F Rigét
Aurore Aubail
Eva Garde
Per Ambus
Robert Drimmie
Mads Peter Heide-Jørgensen
Christian Sonne
Author Affiliation
Department of Bioscience, Arctic Research Centre, Aarhus University, Aarhus 4000, Denmark. Electronic address: rdi@bios.au.dk.
Source
Curr Biol. 2021 Mar 05; :
Date
Mar-05-2021
Language
English
Publication Type
Journal Article
Abstract
The ability of animals to respond to changes in their environment is critical to their persistence. In the Arctic, climate change and mercury exposure are two of the most important environmental threats for top predators.1-3 Rapid warming is causing precipitous sea-ice loss, with consequences on the distribution, composition, and dietary ecology of species4-7 and, thus, exposure to food-borne mercury.8 Current understanding of global change and pollution impacts on Arctic wildlife relies on single-time-point individual data representing a snapshot in time. These data often lack comprehensive temporal resolution and overlook the cumulative lifelong nature of stressors as well as individual variation. To overcome these challenges, we explore the unique capacity of narwhal tusks to characterize chronological lifetime biogeochemical profiles, allowing for investigations of climate-induced dietary changes and contaminant trends. Using temporal patterns of stable isotopes (d13C and d15N) and mercury concentrations in annually deposited dentine growth layer groups in 10 tusks from Northwest Greenland (1962-2010), we show surprising plasticity in narwhal feeding ecology likely resulting from climate-induced changes in sea-ice cover, biological communities, and narwhal migration. Dietary changes consequently impacted mercury exposure primarily through trophic magnification effects. Mercury increased log-linearly over the study period, albeit with an unexpected rise in recent years, likely caused by increased emissions and/or greater bioavailability in a warmer, ice-free Arctic. Our findings are consistent with an emerging pattern in the Arctic of reduced sea-ice leading to changes in the migration, habitat use, food web, and contaminant exposure in Arctic top predators.
PubMed ID
33705717 View in PubMed
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Arctic-adapted dogs emerged at the Pleistocene-Holocene transition.

https://arctichealth.org/en/permalink/ahliterature305477
Source
Science. 2020 06 26; 368(6498):1495-1499
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
06-26-2020
Author
Mikkel-Holger S Sinding
Shyam Gopalakrishnan
Jazmín Ramos-Madrigal
Marc de Manuel
Vladimir V Pitulko
Lukas Kuderna
Tatiana R Feuerborn
Laurent A F Frantz
Filipe G Vieira
Jonas Niemann
Jose A Samaniego Castruita
Christian Carøe
Emilie U Andersen-Ranberg
Peter D Jordan
Elena Y Pavlova
Pavel A Nikolskiy
Aleksei K Kasparov
Varvara V Ivanova
Eske Willerslev
Pontus Skoglund
Merete Fredholm
Sanne Eline Wennerberg
Mads Peter Heide-Jørgensen
Rune Dietz
Christian Sonne
Morten Meldgaard
Love Dalén
Greger Larson
Bent Petersen
Thomas Sicheritz-Pontén
Lutz Bachmann
Øystein Wiig
Tomas Marques-Bonet
Anders J Hansen
M Thomas P Gilbert
Author Affiliation
The GLOBE Institute, University of Copenhagen, Copenhagen, Denmark. mhssinding@gmail.com tomas.marques@upf.edu ajhansen@sund.ku.dk tgilbert@sund.ku.dk.
Source
Science. 2020 06 26; 368(6498):1495-1499
Date
06-26-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Adaptation, Physiological - genetics
Animals
Apolipoproteins - genetics
Arctic Regions
Dogs - genetics
Fatty Acids - metabolism
Genome
Greenland
Haplotypes
Mitochondrial Membrane Transport Proteins - genetics
Selective Breeding
Sequence Analysis, DNA
Siberia
Triglycerides - metabolism
Wolves - genetics
Abstract
Although sled dogs are one of the most specialized groups of dogs, their origin and evolution has received much less attention than many other dog groups. We applied a genomic approach to investigate their spatiotemporal emergence by sequencing the genomes of 10 modern Greenland sled dogs, an ~9500-year-old Siberian dog associated with archaeological evidence for sled technology, and an ~33,000-year-old Siberian wolf. We found noteworthy genetic similarity between the ancient dog and modern sled dogs. We detected gene flow from Pleistocene Siberian wolves, but not modern American wolves, to present-day sled dogs. The results indicate that the major ancestry of modern sled dogs traces back to Siberia, where sled dog-specific haplotypes of genes that potentially relate to Arctic adaptation were established by 9500 years ago.
PubMed ID
32587022 View in PubMed
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Assessing auditory evoked potentials of wild harbor porpoises (Phocoena phocoena).

https://arctichealth.org/en/permalink/ahliterature294363
Source
J Acoust Soc Am. 2016 07; 140(1):442
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
07-2016
Author
Andreas Ruser
Michael Dähne
Abbo van Neer
Klaus Lucke
Janne Sundermeyer
Ursula Siebert
Dorian S Houser
James J Finneran
Eligius Everaarts
Jolanda Meerbeek
Rune Dietz
Signe Sveegaard
Jonas Teilmann
Author Affiliation
Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Foundation, Büsum, SH, Germany.
Source
J Acoust Soc Am. 2016 07; 140(1):442
Date
07-2016
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Acoustic Stimulation
Animals
Auditory Threshold - physiology
Denmark
Evoked Potentials, Auditory - physiology
Evoked Potentials, Auditory, Brain Stem - physiology
Noise - adverse effects
Phocoena - physiology
Abstract
Testing the hearing abilities of marine mammals under water is a challenging task. Sample sizes are usually low, thus limiting the ability to generalize findings of susceptibility towards noise influences. A method to measure harbor porpoise hearing thresholds in situ in outdoor conditions using auditory steady state responses of the brainstem was developed and tested. The method was used on 15 live-stranded animals from the North Sea during rehabilitation, shortly before release into the wild, and on 12 wild animals incidentally caught in pound nets in Denmark (inner Danish waters). Results indicated that although the variability between individuals is wide, the shape of the hearing curve is generally similar to previously published results from behavioral trials. Using 10-kHz frequency intervals between 10 and 160 kHz, best hearing was found between 120 and 130?kHz. Additional testing using one-third octave frequency intervals (from 16 to 160?kHz) allowed for a much faster hearing assessment, but eliminated the fine scale threshold characteristics. For further investigations, the method will be used to better understand the factors influencing sensitivity differences across individuals and to establish population-level parameters describing hearing abilities of harbor porpoises.
PubMed ID
27475168 View in PubMed
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Aviation, melting sea-ice and polar bears.

https://arctichealth.org/en/permalink/ahliterature308401
Source
Environ Int. 2019 12; 133(Pt B):105279
Publication Type
Letter
Date
12-2019
Author
Christian Sonne
Aage K O Alstrup
Rune Dietz
Yong Sik Ok
Tomasz Maciej Ciesielski
Bjørn Munro Jenssen
Author Affiliation
Aarhus University, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark. Electronic address: cs@bios.au.dk.
Source
Environ Int. 2019 12; 133(Pt B):105279
Date
12-2019
Language
English
Publication Type
Letter
Keywords
Air Pollutants - toxicity
Animals
Arctic Regions
Aviation
Carbon Dioxide - toxicity
Climate change
Ecosystem
Ice Cover
Ursidae
Abstract
On 11 May 2019, the Mauna Loa, Hawaii, Earth System Research Laboratory reported the highest CO2 concentration in human meteorological history. Continuing CO2 rise will devastate ecosystems, and ice dependent species like polar bears ultimately will disappear. Commercial aviation is presently a relatively small CO2 contributor, but this CO2 intensive mode of transportation is projected to increase greatly. Scientists and conservationists are often among the most frequent of flyers, despite their recognition that emissions must be reduced. Here we illustrate the carbon footprint of air travel in terms of its impact on the sea ice habitat necessary for polar bear persistence, and suggest our colleagues reduce their air travel where-ever possible. Each metric ton of CO2 emitted melts ~3?m2 of arctic summer sea ice, and current air travel melts over 5000?m2 each year. Each scientist making the short flight from Copenhagen to Oslo to join an IUCN polar bear meeting will melt ~1?m2 of Arctic summer sea-ice. Annually hundreds of scientists and conservationists make frequent flights of much greater distances for AMAP, CAFF, IUCN, and other conservation related meetings. Much of this travel could be avoided with better planning and employing internet linkages for remote participation. When air travel, such as for necessary fieldwork, cannot be easily substituted by Web linkage, we all should search for routes and carriers allowing the lowest CO2 emissions. We encourage all of our colleagues to join 'No Fly Climate Sci' to show their commitment to CO2 reduction and learn more about doing so. As scientists, if we are serious about preserving polar bears and their Arctic sea ice habitat, we need to walk the talk and show an example for the rest of society by significantly reducing our air travel.
PubMed ID
31671313 View in PubMed
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Bioaccumulation and biomagnification of perfluoroalkyl acids and precursors in East Greenland polar bears and their ringed seal prey.

https://arctichealth.org/en/permalink/ahliterature310365
Source
Environ Pollut. 2019 Sep; 252(Pt B):1335-1343
Publication Type
Journal Article
Date
Sep-2019
Author
Gabriel Boisvert
Christian Sonne
Frank F Rigét
Rune Dietz
Robert J Letcher
Author Affiliation
Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada and the Department of Chemistry, Carleton University, Ottawa, ON, Canada.
Source
Environ Pollut. 2019 Sep; 252(Pt B):1335-1343
Date
Sep-2019
Language
English
Publication Type
Journal Article
Keywords
Adipose Tissue - chemistry
Alkanesulfonic Acids - analysis
Animals
Carboxylic Acids - analysis
Environmental monitoring
Female
Fluorocarbons - analysis
Greenland
Liver - chemistry
Male
Seals, Earless - metabolism
Sulfonamides - analysis
Ursidae - metabolism
Abstract
The bioaccumulation and biomagnification of 22 major perfluoroalkyl substances (PFAS) were investigated in tissues of polar bears (Ursus maritimus) and their major prey species, the ringed seal (Pusa hispida), from the Scoresby Sound region of East Greenland. In polar bear liver the mean S4PFSA (perfluoroalkyl sulfonic acid) concentration (C4, C6, C8 and C10) was 2611?±?202?ng/g wet weight (ww; 99% perfluorooctane sulfonate (PFOS)) and two orders of magnitude higher than the 20?±?3?ng/g ww (89% PFOS) concentration in fat. The mean S4PFSAs in seal liver was 111?±?5?ng/g ww (98% PFOS) and three orders of magnitude higher relative to the 0.05?±?0.01?ng/g ww concentration in blubber (100% perfluorohexane sulfonate). Perfluoro-1-octane sulfonamide (FOSA) was quantifiable in bear (mean 10?±?1.4?ng/g ww) and seal (mean 0.6?±?0.1?ng/g ww) liver but not in fat or blubber. The mean S13PFCAs (C4-C18; perfluoroalkyl carboxylic acids) in bear liver (924?±?71?ng/g ww) was much greater than in seal liver (74?±?6?ng/g ww). In bear fat and seal blubber, the mean S13PFCAs were 15?±?1.9 and 0.9?±?0.1?ng/g ww, respectively. Longer chain C11 to C14 PFCAs dominated in bear fat and seal blubber (60-80% of S13PFCA), whereas shorter-chain C9 to C11 PFCAs dominated in the liver (85-90% of S13PFCA). Biomagnification factors (BMFs) were orders of magnitude greater for PFHxS and C9 to C13 PFCAs when based on bear liver to seal blubber rather than bear liver to seal liver, and PFCA (C9 to C13) BMFs decreased with increasing chain length. Seal blubber to bear liver BMFs better reflects the dietary exposure relationship of PFAS between bears and seals.
PubMed ID
31252131 View in PubMed
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84 records – page 1 of 9.