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55 records – page 1 of 6.

Annual movement patterns of endangered ivory gulls: the importance of sea ice.

https://arctichealth.org/en/permalink/ahliterature259274
Source
PLoS One. 2014;9(12):e115231
Publication Type
Article
Date
2014
Author
Nora C Spencer
H Grant Gilchrist
Mark L Mallory
Source
PLoS One. 2014;9(12):e115231
Date
2014
Language
English
Publication Type
Article
Abstract
The ivory gull (Pagophila eburnea) is an endangered seabird that spends its entire year in the Arctic environment. In the past three decades, threats from various sources have contributed to a >70% decline in Canada. To assess the annual habitat needs of this species, we attached satellite transmitters to 12 ivory gulls on Seymour Island, Nunavut in 2010, which provided up to four breeding seasons of tracking data. Analysis of migratory behaviour revealed considerable individual variation of post-breeding migratory route selection. Ivory gulls traveled a median of 74 days during post-breeding migration, but only 18 days during pre-breeding migration. In contrast to predictions, ivory gulls did not use the Greenland coast during migratory periods. Ivory gulls overwintered near the ice edge in Davis Strait, but also used the Labrador Sea in late February and March. We suggest that the timing of formation and recession and extent of sea ice plays a large role in ivory gull distribution and migratory timing.
PubMed ID
25551556 View in PubMed
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Anthropogenic litter in marine waters and coastlines of Arctic Canada and West Greenland.

https://arctichealth.org/en/permalink/ahliterature311677
Source
Sci Total Environ. 2021 Apr 07; 783:146971
Publication Type
Journal Article
Date
Apr-07-2021
Author
Mark L Mallory
Julia Baak
Carina Gjerdrum
Olivia E Mallory
Brittany Manley
Cedar Swan
Jennifer F Provencher
Author Affiliation
Biology, Acadia University, 15 University Avenue, Wolfville, Nova Scotia B4P 2R6, Canada. Electronic address: mark.mallory@acadiau.ca.
Source
Sci Total Environ. 2021 Apr 07; 783:146971
Date
Apr-07-2021
Language
English
Publication Type
Journal Article
Abstract
Despite much interest and research into marine litter (including plastic debris) on beaches globally, relatively little is known about the density and distribution of this pollutant in Arctic environments, particularly Arctic Canada and West Greenland. We used two sources of data, observations of floating litter from vessels at sea, and quadrat surveys of litter on low slope beaches, to establish the first measures of anthropogenic litter densities in this region. Most litter observed (73%) was plastic, predominantly fragments, threads and sheets, with a mean density of 1.0 ± 1.7 (SD) items·m-2 along sandy/gravel beaches (median 1), and items were observed on the ocean surface as far as 78°N. Litter densities were significantly greater for sites within 5 km of communities, and much of the litter near remote communities was clearly from local sources. However, contrary to our predictions, we did not find that litter densities decreased with increasing latitude. Collectively, our results confirm that this global pollutant is distributed around much of this portion of the Arctic, and that better waste management strategies in a number of sectors may help reduce its occurrence in this remote region.
PubMed ID
33865122 View in PubMed
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Arctic cleansing diet: Sex-specific variation in the rapid elimination of contaminants by the world's champion migrant, the Arctic tern.

https://arctichealth.org/en/permalink/ahliterature301721
Source
Sci Total Environ. 2019 Nov 01; 689:716-724
Publication Type
Journal Article
Date
Nov-01-2019
Author
Mark L Mallory
Christine M Anderson
Birgit M Braune
Isabeau Pratte
Jennifer F Provencher
Author Affiliation
Biology, Acadia University, 33 Westwood Avenue, Wolfville, NS B4P 2R6, Canada. Electronic address: mark.mallory@acadiau.ca.
Source
Sci Total Environ. 2019 Nov 01; 689:716-724
Date
Nov-01-2019
Language
English
Publication Type
Journal Article
Abstract
Contamination of Arctic marine environments continues to be a concern for wildlife managers. Because the Arctic is a sink for the long-range transport of persistent organic pollutants (POPs), many studies have detected high concentrations of POPs in various Arctic birds. In this study from high Arctic Canada, we show that male Arctic terns (Sterna paradisaea), which migrate from the Antarctic to the Arctic annually to breed, decline in concentrations of many hepatic POPs through the breeding season. This suggests that local Arctic food webs are less contaminated than regions where terns fed during or migration, despite that the terns appear to feed at a higher trophic level near their colony.
PubMed ID
31280153 View in PubMed
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Both short and long distance migrants use energy-minimizing migration strategies in North American herring gulls.

https://arctichealth.org/en/permalink/ahliterature305580
Source
Mov Ecol. 2020; 8:26
Publication Type
Journal Article
Date
2020
Author
Christine M Anderson
H Grant Gilchrist
Robert A Ronconi
Katherine R Shlepr
Daniel E Clark
David A Fifield
Gregory J Robertson
Mark L Mallory
Author Affiliation
Department of Biology, Acadia University, 33 Westwood Ave, Wolfville, NS B4P 2R6 Canada.
Source
Mov Ecol. 2020; 8:26
Date
2020
Language
English
Publication Type
Journal Article
Abstract
Recent studies have proposed that birds migrating short distances migrate at an overall slower pace, minimizing energy expenditure, while birds migrating long distances minimize time spent on migration to cope with seasonal changes in environmental conditions.
We evaluated variability in the migration strategies of Herring Gulls (Larus argentatus), a generalist species with flexible foraging and flight behaviour. We tracked one population of long distance migrants and three populations of short distance migrants, and compared the directness of their migration routes, their overall migration speed, their travel speed, and their use of stopovers.
Our research revealed that Herring Gulls breeding in the eastern Arctic migrate long distances to spend the winter in the Gulf of Mexico, traveling more than four times farther than gulls from Atlantic Canada during autumn migration. While all populations used indirect routes, the long distance migrants were the least direct. We found that regardless of the distance the population traveled, Herring Gulls migrated at a slower overall migration speed than predicted by Optimal Migration Theory, but the long distance migrants had higher speeds on travel days. While long distance migrants used more stopover days overall, relative to the distance travelled all four populations used a similar number of stopover days.
When taken in context with other studies, we expect that the migration strategies of flexible generalist species like Herring Gulls may be more influenced by habitat and food resources than migration distance.
PubMed ID
32549986 View in PubMed
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Breeding seabirds as vectors of microplastics from sea to land: Evidence from colonies in Arctic Canada.

https://arctichealth.org/en/permalink/ahliterature304423
Source
Sci Total Environ. 2021 Apr 10; 764:142808
Publication Type
Journal Article
Date
Apr-10-2021
Author
Madelaine P T Bourdages
Jennifer F Provencher
Julia E Baak
Mark L Mallory
Jesse C Vermaire
Author Affiliation
Carleton University, Geography and Environmental Studies, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada. Electronic address: madelainebourdages@cmail.carleton.ca.
Source
Sci Total Environ. 2021 Apr 10; 764:142808
Date
Apr-10-2021
Language
English
Publication Type
Journal Article
Keywords
Animals
Arctic Regions
Birds
Canada
Environmental monitoring
Microplastics
Plastics
Abstract
The presence and persistence of microplastics in the environment is increasingly recognized, however, how they are distributed throughout environmental systems requires further understanding. Seabirds have been identified as vectors of chemical contaminants from marine to terrestrial environments, and studies have recently identified seabirds as possible vectors of plastic pollution in the marine environment. However, their role in the distribution of microplastic pollution in the Arctic has yet to be explored. We examined two species of seabirds known to ingest plastics: northern fulmars (Fulmarus glacialis; n = 27) and thick-billed murres (Uria lomvia; n = 30) as potential vectors for the transport of microplastics in and around breeding colonies. Our results indicated anthropogenic particles in the faecal precursors of both species. Twenty-four anthropogenic particles were found in the fulmar faecal precursor samples (M = 0.89, SD = 1.09; 23 fibres and one fragment), and 10 anthropogenic particles were found in the murre faecal precursor samples (M = 0.33, SD = 0.92; 5 fibres, 4 fragments, and one foam). Through the use of bird population surveys and the quantification of anthropogenic particles found in the faecal precursors of sampled seabirds from the same colony, we estimate that fulmars and murres may deposit between 3.3 (CIboot 1.9 × 106-4.9 × 106) and 45.5 (CIboot 9.1 × 106-91.9 × 106) million anthropogenic particles, respectively, per year into the environment during their breeding period at these colonies. These estimates indicate that migratory seabirds could be contributing to the distribution and local hotspots of microplastics in Arctic environments, however, they are still likely a relatively small source of plastic pollution in terms of mass in the environment and may not contribute as much as other reported sources such as atmospheric deposition in the Arctic.
PubMed ID
33082039 View in PubMed
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Changes in food web structure alter trends of mercury uptake at two seabird colonies in the canadian arctic.

https://arctichealth.org/en/permalink/ahliterature258239
Source
Environ Sci Technol. 2014 Nov 18;48(22):13246-52
Publication Type
Article
Date
Nov-18-2014
Author
Birgit M Braune
Anthony J Gaston
Keith A Hobson
H Grant Gilchrist
Mark L Mallory
Author Affiliation
Environment Canada, National Wildlife Research Centre, Carleton University , Raven Road, Ottawa, Ontario Canada K1A 0H3.
Source
Environ Sci Technol. 2014 Nov 18;48(22):13246-52
Date
Nov-18-2014
Language
English
Publication Type
Article
Abstract
Arctic ecosystems are changing in response to climate change and some Arctic food web structures are being affected in ways which may have potential consequences for the biomagnification of environmental contaminants. Here, we examined how a shift in diet of an Arctic seabird resulted in a change of trophic position and how that change affected exposure to mercury over time. The thick-billed murre (Uria lomvia), which breeds in the eastern Canadian Arctic, has been monitored for diet and environmental contaminants at two colonies, one in northern Hudson Bay and one in the high Arctic. As a result of a change in diet, murres breeding in Hudson Bay lowered their trophic position which, in turn, should affect their mercury exposure over time. After adjusting mercury concentrations in murre eggs for trophic position, the temporal trend of mercury in Hudson Bay murre eggs changed from nonsignificant to a significantly increasing trend. Valid trends can be deduced only when factors, such as diet, have been taken into account.
PubMed ID
25404000 View in PubMed
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Changes in trophic position affect rates of contaminant decline at two seabird colonies in the Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature260326
Source
Ecotoxicol Environ Saf. 2015 May;115:7-13
Publication Type
Article
Date
May-2015
Author
Birgit M Braune
Anthony J Gaston
Keith A Hobson
H. Grant Gilchrist
Mark L Mallory
Source
Ecotoxicol Environ Saf. 2015 May;115:7-13
Date
May-2015
Language
English
Publication Type
Article
Abstract
Some Arctic food web structures are being affected by climate change with potential consequences for long-term trends of environmental contaminants. We examined the effects of changes in trophic position of an Arctic-breeding seabird, the thick-billed murre (Uria lomvia), on declining rates of six major organochlorines (hexachlorobenzene, heptachlor epoxide, oxychlordane, dieldrin, p,p'-DDE and S69PCB) at two breeding colonies in the Canadian Arctic, one in northern Hudson Bay and one in the high Arctic. As a result of a change in diet, murres breeding in Hudson Bay lowered their trophic position during 1993-2013. After adjusting for the change in trophic position using egg d(15)N values, the rates of decline in concentrations of all six organochlorines were reduced in the Hudson Bay murre eggs. In contrast, the murres at the high Arctic colony experienced an increase in trophic position which resulted in an increase in the rates of decline for all adjusted concentrations, except for p,p'-DDE and S69PCB which remained relatively unchanged. This suggests that the dramatic reduction in emissions of these compounds during the 1970s/1980s had a greater influence on the time trends than changes in diet at the high Arctic colony. Linkages between climate change and food web processes are complex, and may have serious consequences for our understanding of contaminant temporal trends. Valid trends can be deduced only when these factors have been taken into account.
PubMed ID
25666731 View in PubMed
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Circumpolar dynamics of a marine top-predator track ocean warming rates.

https://arctichealth.org/en/permalink/ahliterature281658
Source
Glob Chang Biol. 2017 Apr 07;
Publication Type
Article
Date
Apr-07-2017
Author
Sébastien Descamps
Tycho Anker-Nilssen
Robert T Barrett
David B Irons
Flemming Merkel
Gregory J Robertson
Nigel G Yoccoz
Mark L Mallory
William A Montevecchi
David Boertmann
Yuri Artukhin
Signe Christensen-Dalsgaard
Kjell-Einar Erikstad
H Grant Gilchrist
Aili L Labansen
Svein-Håkon Lorentsen
Anders Mosbech
Bergur Olsen
Aevar Petersen
Jean-Francois Rail
Heather M Renner
Hallvard Strøm
Geir H Systad
Sabina I Wilhelm
Larisa Zelenskaya
Source
Glob Chang Biol. 2017 Apr 07;
Date
Apr-07-2017
Language
English
Publication Type
Article
Abstract
Global warming is a nonlinear process, and temperature may increase in a stepwise manner. Periods of abrupt warming can trigger persistent changes in the state of ecosystems, also called regime shifts. The responses of organisms to abrupt warming and associated regime shifts can be unlike responses to periods of slow or moderate change. Understanding of nonlinearity in the biological responses to climate warming is needed to assess the consequences of ongoing climate change. Here, we demonstrate that the population dynamics of a long-lived, wide-ranging marine predator are associated with changes in the rate of ocean warming. Data from 556 colonies of black-legged kittiwakes Rissa tridactyla distributed throughout its breeding range revealed that an abrupt warming of sea-surface temperature in the 1990s coincided with steep kittiwake population decline. Periods of moderate warming in sea temperatures did not seem to affect kittiwake dynamics. The rapid warming observed in the 1990s may have driven large-scale, circumpolar marine ecosystem shifts that strongly affected kittiwakes through bottom-up effects. Our study sheds light on the nonlinear response of a circumpolar seabird to large-scale changes in oceanographic conditions and indicates that marine top predators may be more sensitive to the rate of ocean warming rather than to warming itself.
PubMed ID
28387042 View in PubMed
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Climate Influence on Legacy Organochlorine Pollutants in Arctic Seabirds.

https://arctichealth.org/en/permalink/ahliterature297799
Source
Environ Sci Technol. 2019 Mar 05; 53(5):2518-2528
Publication Type
Journal Article
Date
Mar-05-2019
Author
Karen L Foster
Birgit M Braune
Anthony J Gaston
Mark L Mallory
Author Affiliation
Karen Foster Environmental Research , Peterborough , ON K9J 8L2 , Canada.
Source
Environ Sci Technol. 2019 Mar 05; 53(5):2518-2528
Date
Mar-05-2019
Language
English
Publication Type
Journal Article
Abstract
Changing climate can influence the transport of chemical pollutants into Arctic regions and their fate once there. However, the influence of weather or climate variables on organochlorine accumulation in Arctic wildlife, including seabirds, and associated time scale are poorly understood. We assessed the interannual relationships between a suite of weather/climate variables for time lags of 0 to 10 yr and organochlorine pollutant concentrations spanning 1975-2014 in eggs of two seabird species (northern fulmar Fulmarus glacialis, thick-billed murre Uria lomvia) that breed in the Canadian High Arctic. The majority of variability in the data was associated with declining organochlorine emissions (up to 70.2% for murres and 77.4% for fulmars). By controlling for emissions using principal component ordination and general linear modeling, correlations with the North Atlantic Oscillation (NAO) were found for fulmars and with rainfall for murres, after a time lag of 4-9 yr between weather/climate conditions and egg collection. Our results suggest that with increasingly NAO+ conditions and increasing rainfall associated with climate change, concentrations of certain organochlorines such as hexachlorobenzene and p, p'-DDE have increased, dependent on seabird species and ecology as well as partitioning characteristics of the chemical. Analysis of a truncated version of the data sets (2005-2014), consistent with typical time series lengths for environmental pollutants in Arctic wildlife, found correlations with precipitation for murres but not with NAO for fulmars, suggesting that longer time series better elucidate relationships with broad-scale climate indices. Organochlorine pollutant data sets spanning 40 years, which is rare for Arctic wildlife, for two species of seabird were assessed, and the results highlight the association between weather/climate and pollutant accumulation in Arctic food webs and the critical role of ongoing monitoring to effectively elucidate these relationships.
PubMed ID
30688438 View in PubMed
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Climate influence on mercury in Arctic seabirds.

https://arctichealth.org/en/permalink/ahliterature308557
Source
Sci Total Environ. 2019 Nov 25; 693:133569
Publication Type
Journal Article
Date
Nov-25-2019
Author
Karen L Foster
Birgit M Braune
Anthony J Gaston
Mark L Mallory
Author Affiliation
Karen Foster Environmental Research, Peterborough, ON K9J 8L2, Canada; Applications of Modelling & Quantitative Methods (AMOD), Trent University, Peterborough, ON K9L 0G2, Canada.
Source
Sci Total Environ. 2019 Nov 25; 693:133569
Date
Nov-25-2019
Language
English
Publication Type
Journal Article
Keywords
Animals
Arctic Regions
Charadriiformes - metabolism
Climate
Environmental monitoring
Environmental Pollutants - metabolism
Mercury - metabolism
Abstract
The historic influence of interannual weather and climate variability on total mercury concentrations (THg) in the eggs of two species of Arctic seabird in the Canadian High Arctic was investigated. Time series of THg in the eggs of northern fulmars (Fulmarus glacialis) and thick-billed murres (Uria lomvia) from Prince Leopold Island span 40?years (1975-2014), making these among the longest time series available for contaminants in Arctic wildlife and uniquely suitable for evaluation of long-term climate and weather influence. We compiled a suite of weather and climate time series reflecting atmospheric (air temperature, wind speed, sea level pressure) and oceanic (sea surface temperature, sea ice cover) conditions, atmosphere-ocean transfer (snow and rain), as well as broad-scale teleconnection indices such as the Arctic Oscillation (AO) and North Atlantic Oscillation (NAO). We staggered these to the optimal time lag, then in a tiered approach of successive General Linear Models (GLMs), strategically added them to GLMs to identify possible key predictors and assess any main effects on THg concentrations. We investigated time lags of 0 to 10?years between weather/climate shifts and egg collections. For both fulmars and murres, after time lags of two to seven years, the most parsimonious models included NAO and temperature, and for murres, snowfall, while the fulmar model also included sea ice. Truncated versions of the datasets (2005-2014), reflective of typical time series length for THg in Arctic wildlife, were separately assessed and generally identified similar weather predictors and effects as the full time series, but not for NAO, indicating that longer time series are more effective at elucidating relationships with broad scale climate indices. Overall, the results suggest a significant and larger than expected effect of weather and climate on THg concentrations in Arctic seabirds.
PubMed ID
31634995 View in PubMed
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55 records – page 1 of 6.