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Climate change reduces reproductive success of an Arctic herbivore through trophic mismatch.

https://arctichealth.org/en/permalink/ahliterature95588
Source
Philos Trans R Soc Lond B Biol Sci. 2008 Jul 12;363(1501):2369-75
Publication Type
Article
Date
Jul-12-2008
Author
Post Eric
Forchhammer Mads C
Author Affiliation
Department of Biology, Penn State University, 208 Mueller Lab, University Park, PA 16802, USA. esp10@psu.edu
Source
Philos Trans R Soc Lond B Biol Sci. 2008 Jul 12;363(1501):2369-75
Date
Jul-12-2008
Language
English
Publication Type
Article
Keywords
Animals
Fertility - physiology
Food chain
Greenhouse Effect
Greenland
Plants - growth & development
Population Dynamics
Reindeer - physiology
Seasons
Temperature
Abstract
In highly seasonal environments, offspring production by vertebrates is timed to coincide with the annual peak of resource availability. For herbivores, this resource peak is represented by the annual onset and progression of the plant growth season. As plant phenology advances in response to climatic warming, there is potential for development of a mismatch between the peak of resource demands by reproducing herbivores and the peak of resource availability. For migratory herbivores, such as caribou, development of a trophic mismatch is particularly likely because the timing of their seasonal migration to summer ranges, where calves are born, is cued by changes in day length, while onset of the plant-growing season on the same ranges is cued by local temperatures. Using data collected since 1993 on timing of calving by caribou and timing of plant growth in West Greenland, we document the consequences for reproductive success of a developing trophic mismatch between caribou and their forage plants. As mean spring temperatures at our study site have risen by more than 4 degrees C, caribou have not kept pace with advancement of the plant-growing season on their calving range. As a consequence, offspring mortality has risen and offspring production has dropped fourfold.
PubMed ID
18006410 View in PubMed
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Ecological dynamics across the Arctic associated with recent climate change.

https://arctichealth.org/en/permalink/ahliterature94282
Source
Science. 2009 Sep 11;325(5946):1355-8
Publication Type
Article
Date
Sep-11-2009
Author
Post Eric
Forchhammer Mads C
Bret-Harte M Syndonia
Callaghan Terry V
Christensen Torben R
Elberling Bo
Fox Anthony D
Gilg Olivier
Hik David S
Høye Toke T
Ims Rolf A
Jeppesen Erik
Klein David R
Madsen Jesper
McGuire A David
Rysgaard Søren
Schindler Daniel E
Stirling Ian
Tamstorf Mikkel P
Tyler Nicholas J C
van der Wal Rene
Welker Jeffrey
Wookey Philip A
Schmidt Niels Martin
Aastrup Peter
Author Affiliation
Department of Biology, Penn State University, 208 Mueller Lab, University Park, PA 16802, USA. esp10@psu.edu
Source
Science. 2009 Sep 11;325(5946):1355-8
Date
Sep-11-2009
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Climatic Processes
Cold Climate
Ecosystem
Greenhouse Effect
Ice Cover
Plants - growth & development
Population Dynamics
Research
Abstract
At the close of the Fourth International Polar Year, we take stock of the ecological consequences of recent climate change in the Arctic, focusing on effects at population, community, and ecosystem scales. Despite the buffering effect of landscape heterogeneity, Arctic ecosystems and the trophic relationships that structure them have been severely perturbed. These rapid changes may be a bellwether of changes to come at lower latitudes and have the potential to affect ecosystem services related to natural resources, food production, climate regulation, and cultural integrity. We highlight areas of ecological research that deserve priority as the Arctic continues to warm.
PubMed ID
19745143 View in PubMed
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The influence of weather conditions on the activity of high-arctic arthropods inferred from long-term observations.

https://arctichealth.org/en/permalink/ahliterature95542
Source
BMC Ecol. 2008;8:8
Publication Type
Article
Date
2008
Author
Høye Toke T
Forchhammer Mads C
Author Affiliation
Department of Arctic Environment, National Environmental Research Institute, University of Aarhus, PO Box 358 Frederiksborgvej 399, DK-4000 Roskilde, Denmark. toh@dmu.dk.
Source
BMC Ecol. 2008;8:8
Date
2008
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Arthropods - physiology
Ecosystem
Environmental monitoring
Greenhouse Effect
Models, Statistical
Population Dynamics
Weather
Abstract
BACKGROUND: Climate change is particularly pronounced in the High Arctic and a better understanding of the repercussions on ecological processes like herbivory, predation and pollination is needed. Arthropods play an important role in the high-arctic ecosystem and this role is determined by their density and activity. However, density and activity may be sensitive to separate components of climate. Earlier emergence due to advanced timing of snowmelt following climate change may expose adult arthropods to unchanged temperatures but higher levels of radiation. The capture rate of arthropods in passive open traps like pitfall trap integrates density and activity and, therefore, serves as a proxy of the magnitude of such arthropod-related ecological processes. We used arthropod pitfall trapping data and weather data from 10 seasons in high-arctic Greenland to identify climatic effects on the activity pattern of nine arthropod taxa. RESULTS: We were able to statistically separate the variation in capture rates into a non-linear component of capture date (density) and a linear component of weather (activity). The non-linear proxy of density always accounted for more of the variation than the linear component of weather. After accounting for the seasonal phenological development, the most important weather variable influencing the capture rate of flying arthropods was temperature, while surface-dwelling species were principally influenced by solar radiation. CONCLUSION: Consistent with previous findings, air temperature best explained variation in the activity level of flying insects. An advancement of the phenology in this group due to earlier snowmelt will make individuals appear earlier in the season, but parallel temperature increases could mean that individuals are exposed to similar temperatures. Hence, the effect of climatic changes on the activity pattern in this group may be unchanged. In contrast, we found that solar radiation is a better proxy of activity levels than air temperature in surface-dwelling arthropods. An advancement of the phenology may expose surface-dwelling arthropods to higher levels of solar radiation, which suggest that their locomotory performance is enhanced and their contribution to ecological processes is increased.
PubMed ID
18454856 View in PubMed
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Inter-annual growth of Arctic charr (Salvelinus alpinus, L.) in relation to climate variation.

https://arctichealth.org/en/permalink/ahliterature80936
Source
BMC Ecol. 2006;6:10
Publication Type
Article
Date
2006
Author
Kristensen David M
Jørgensen Thomas R
Larsen Rasmus K
Forchhammer Mads C
Christoffersen Kirsten S
Author Affiliation
Dept. of Medical Biochemistry and Genetics A, Panum Institute, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark. moebjerg@imbg.ku.dk
Source
BMC Ecol. 2006;6:10
Date
2006
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Cold Climate
Trout - growth & development
Abstract
BACKGROUND: Major changes in climate have been observed in the Arctic and climate models predict further amplification of the enhanced greenhouse effect at high-latitudes leading to increased warming. We propose that warming in the Arctic may affect the annual growth conditions of the cold adapted Arctic charr and that such effects can already be detected retrospectrally using otolith data. RESULTS: Inter-annual growth of the circumpolar Arctic charr (Salvelinus alpinus, L.) was analysed in relation to climatic changes observed in the Arctic during the last two decades. Arctic charr were sampled from six locations at Qeqertarsuaq in West Greenland, where climate data have been recorded since 1990. Two fish populations met the criteria of homogeny and, consequently, only these were used in further analyses. The results demonstrate a complex coupling between annual growth rates and fluctuations in annual mean temperatures and precipitation. Significant changes in temporal patterns of growth were observed between cohorts of 1990 and 2004. CONCLUSION: Differences in pattern of growth appear to be a consequence of climatic changes over the last two decades and we thereby conclude that climatic affects short term and inter-annual growth as well as influencing long term shifts in age-specific growth patterns in population of Arctic charr.
PubMed ID
16934162 View in PubMed
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Phenological sequences reveal aggregate life history response to climatic warming.

https://arctichealth.org/en/permalink/ahliterature95551
Source
Ecology. 2008 Feb;89(2):363-70
Publication Type
Article
Date
Feb-2008
Author
Post Eric S
Pedersen Christian
Wilmers Christopher C
Forchhammer Mads C
Author Affiliation
Department of Biology, Penn State University, 208 Mueller Lab, University Park, Pennsylvania 16802, USA. Esp10@psu.edu
Source
Ecology. 2008 Feb;89(2):363-70
Date
Feb-2008
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Betula - growth & development - physiology
Caryophyllaceae - growth & development - physiology
Ecosystem
Greenhouse Effect
Population Dynamics
Population Growth
Salix - growth & development - physiology
Species Specificity
Temperature
Time Factors
Abstract
Climatic warming is associated with organisms breeding earlier in the season than is typical for their species. In some species, however, response to warming is more complex than a simple advance in the timing of all life history events preceding reproduction. Disparities in the extent to which different components of the reproductive phenology of organisms vary with climatic warming indicate that not all life history events are equally responsive to environmental variation. Here, we propose that our understanding of phenological response to climate change can be improved by considering entire sequences of events comprising the aggregate life histories of organisms preceding reproduction. We present results of a two-year warming experiment conducted on 33 individuals of three plant species inhabiting a low-arctic site. Analysis of phenological sequences of three key events for each species revealed how the aggregate life histories preceding reproduction responded to warming, and which individual events exerted the greatest influence on aggregate life history variation. For alpine chickweed (Cerastium alpinum), warming elicited a shortening of the duration of the emergence stage by 2.5 days on average, but the aggregate life history did not differ between warmed and ambient plots. For gray willow (Salix glauca), however, all phenological events monitored occurred earlier on warmed than on ambient plots, and warming reduced the aggregate life history of this species by 22 days on average. Similarly, in dwarf birch (Betula nana), warming advanced flower bud set, blooming, and fruit set and reduced the aggregate life history by 27 days on average. Our approach provides important insight into life history responses of many organisms to climate change and other forms of environmental variation. Such insight may be compromised by considering changes in individual phenological events in isolation.
PubMed ID
18409426 View in PubMed
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Spatial synchrony of local populations has increased in association with the recent Northern Hemisphere climate trend.

https://arctichealth.org/en/permalink/ahliterature95853
Source
Proc Natl Acad Sci U S A. 2004 Jun 22;101(25):9286-90
Publication Type
Article
Date
Jun-22-2004
Author
Post Eric
Forchhammer Mads C
Author Affiliation
Department of Biology, Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA. esp10@psu.edu
Source
Proc Natl Acad Sci U S A. 2004 Jun 22;101(25):9286-90
Date
Jun-22-2004
Language
English
Publication Type
Article
Keywords
Animals
Animals, Wild
Climate
Denmark
Greenhouse Effect
Greenland
Humans
Population Dynamics
Temperature
Weather
Abstract
According to ecological theory, populations whose dynamics are entrained by environmental correlation face increased extinction risk as environmental conditions become more synchronized spatially. This prediction is highly relevant to the study of ecological consequences of climate change. Recent empirical studies have indicated, for example, that large-scale climate synchronizes trophic interactions and population dynamics over broad spatial scales in freshwater and terrestrial systems. Here, we present an analysis of century-scale, spatially replicated data on local weather and the population dynamics of caribou in Greenland. Our results indicate that spatial autocorrelation in local weather has increased with large-scale climatic warming. This increase in spatial synchrony of environmental conditions has been matched, in turn, by an increase in the spatial synchrony of local caribou populations toward the end of the 20th century. Our results indicate that spatial synchrony in environmental conditions and the populations influenced by them are highly variable through time and can increase with climatic warming. We suggest that if future warming can increase population synchrony, it may also increase extinction risk.
PubMed ID
15197267 View in PubMed
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Synchronization of animal population dynamics by large-scale climate.

https://arctichealth.org/en/permalink/ahliterature95919
Source
Nature. 2002 Nov 14;420(6912):168-71
Publication Type
Article
Date
Nov-14-2002
Author
Post Eric
Forchhammer Mads C
Author Affiliation
Department of Biology, The Pennsylvania State University, 208 Mueller Lab, University Park, Pennsylvania 16802, USA. esp10@psu.edu
Source
Nature. 2002 Nov 14;420(6912):168-71
Date
Nov-14-2002
Language
English
Publication Type
Article
Keywords
Animals
Atlantic Ocean
Climate
Greenland
Population Dynamics
Reindeer - physiology
Ruminants - physiology
Seasons
Species Specificity
Temperature
Weather
Abstract
The hypothesis that animal population dynamics may be synchronized by climate is highly relevant in the context of climate change because it suggests that several populations might respond simultaneously to climatic trends if their dynamics are entrained by environmental correlation. The dynamics of many species throughout the Northern Hemisphere are influenced by a single large-scale climate system, the North Atlantic Oscillation (NAO), which exerts highly correlated regional effects on local weather. But efforts to attribute synchronous fluctuations of contiguous populations to large-scale climate are confounded by the synchronizing influences of dispersal or trophic interactions. Here we report that the dynamics of caribou and musk oxen on opposite coasts of Greenland show spatial synchrony among populations of both species that correlates with the NAO index. Our analysis shows that the NAO has an influence in the high degree of cross-species synchrony between pairs of caribou and musk oxen populations separated by a minimum of 1,000 km of inland ice. The vast distances, and complete physical and ecological separation of these species, rule out spatial coupling by dispersal or interaction. These results indicate that animal populations of different species may respond synchronously to global climate change over large regions.
Notes
Comment In: Nature. 2004 Feb 19;427(6976):697-8; discussion 69814973473
PubMed ID
12432390 View in PubMed
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Warming, plant phenology and the spatial dimension of trophic mismatch for large herbivores.

https://arctichealth.org/en/permalink/ahliterature95532
Source
Proc Biol Sci. 2008 Sep 7;275(1646):2005-13
Publication Type
Article
Date
Sep-7-2008
Author
Post Eric
Pedersen Christian
Wilmers Christopher C
Forchhammer Mads C
Author Affiliation
Department of Biology, Penn State University, 208 Mueller Lab, University Park, PA 16802, USA. esp10@psu.edu
Source
Proc Biol Sci. 2008 Sep 7;275(1646):2005-13
Date
Sep-7-2008
Language
English
Publication Type
Article
Keywords
Animals
Animals, Newborn
Ecosystem
Female
Greenhouse Effect
Multivariate Analysis
Plants - growth & development
Population Dynamics
Regression Analysis
Reindeer - growth & development
Abstract
Temporal advancement of resource availability by warming in seasonal environments can reduce reproductive success of vertebrates if their own reproductive phenology does not also advance with warming. Indirect evidence from large-scale analyses suggests, however, that migratory vertebrates might compensate for this by tracking phenological variation across landscapes. Results from our two-year warming experiment combined with seven years of observations of plant phenology and offspring production by caribou (Rangifer tarandus) in Greenland, however, contradict evidence from large-scale analyses. At spatial scales relevant to the foraging horizon of individual herbivores, spatial variability in plant phenology was reduced--not increased--by both experimental and observed warming. Concurrently, offspring production by female caribou declined with reductions in spatial variability in plant phenology. By highlighting the spatial dimension of trophic mismatch, these results reveal heretofore unexpected adverse consequences of climatic warming for herbivore population ecology.
PubMed ID
18495618 View in PubMed
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9 records – page 1 of 1.