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18 records – page 1 of 2.

Climate, changing phenology, and other life history traits: nonlinearity and match-mismatch to the environment.

https://arctichealth.org/en/permalink/ahliterature95924
Source
Proc Natl Acad Sci U S A. 2002 Oct 15;99(21):13379-81
Publication Type
Article
Date
Oct-15-2002
Author
Stenseth Nils Chr
Mysterud Atle
Author Affiliation
Department of Biology, Division of Zoology, University of Oslo, P.O. Box 1050 Blindern, N-0316 Oslo, Norway. n.c.stenseth@bio.uio.no
Source
Proc Natl Acad Sci U S A. 2002 Oct 15;99(21):13379-81
Date
Oct-15-2002
Language
English
Publication Type
Article
Keywords
Animals
Birds - physiology
Ecosystem
Female
Greenhouse Effect
Male
Models, Biological
Reproduction
Seasons
Notes
Comment On: Proc Natl Acad Sci U S A. 2002 Oct 15;99(21):13595-912370441
PubMed ID
12370424 View in PubMed
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Climatic change as an engine for speciation in flightless Orthoptera species inhabiting African mountains.

https://arctichealth.org/en/permalink/ahliterature95455
Source
Mol Ecol. 2009 Jan;18(1):93-108
Publication Type
Article
Date
Jan-2009
Author
Voje Kjetil Lysne
Hemp Claudia
Flagstad Øystein
Saetre Glenn-Peter
Stenseth Nils Chr
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo, Norway.
Source
Mol Ecol. 2009 Jan;18(1):93-108
Date
Jan-2009
Language
English
Publication Type
Article
Keywords
Africa, Eastern
Animals
Bayes Theorem
Climate
DNA, Mitochondrial - genetics
Ecosystem
Evolution, Molecular
Gene Flow
Genetic Speciation
Geography
Models, Genetic
Orthoptera - classification - genetics
Phylogeny
Sequence Analysis, DNA
Species Specificity
Abstract
Many East African mountains are characterized by an exceptionally high biodiversity. Here we assess the hypothesis that climatic fluctuations during the Plio-Pleistocene led to ecological fragmentation with subsequent genetic isolation and speciation in forest habitats in East Africa. Hypotheses on speciation in savannah lineages are also investigated. To do this, mitochondrial DNA sequences from a group of bush crickets consisting of both forest and savannah inhabiting taxa were analysed in relation to Plio-Pleistocene range fragmentations indicated by palaeoclimatic studies. Coalescent modelling and mismatch distributions were used to distinguish between alternative biogeographical scenarios. The results indicate two radiations: the earliest one overlaps in time with the global spread of C4 grasslands and only grassland inhabiting lineages originated in this radiation. Climatically induced retraction of forest to higher altitudes about 0.8 million years ago, promoting vicariant speciation in species inhabiting the montane zone, can explain the second radiation. Although much of the biodiversity in East Africa is presently threatened by climate change, past climatic fluctuations appear to have contributed to the species richness observed in the East African hot spots. Perceiving forests as centres of speciation reinforces the importance of conserving the remaining forest patches in the region.
PubMed ID
19140967 View in PubMed
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Density dependence and density independence during the early life stages of four marine fish stocks.

https://arctichealth.org/en/permalink/ahliterature77697
Source
Ecology. 2007 Mar;88(3):625-34
Publication Type
Article
Date
Mar-2007
Author
Dingsør Gjert E
Ciannelli Lorenzo
Chan Kung-Sik
Ottersen Geir
Stenseth Nils Chr
Author Affiliation
Department of Biology, University of Bergen, P.O. Box 7800, N-5020 Bergen, Norway.
Source
Ecology. 2007 Mar;88(3):625-34
Date
Mar-2007
Language
English
Publication Type
Article
Abstract
Recruitment variability caused by density-dependent and density-independent processes is an important area within the study of fish dynamics. These processes can exhibit nonlinearities and nonadditive properties that may have profound dynamic effects. We investigate the importance of population density (i.e., density dependence) and environmental forcing (i.e., density independence) on the age-0 and age-1 abundance of capelin (Mallotus villosus), northeast Arctic cod (Gadus morhua), northeast Arctic haddock (Melanogrammus aeglefinus), and Norwegian spring spawning herring (Clupea harengus) in the Barents Sea. We use statistical methods that explicitly account for nonlinearities and nonadditive interactions between internal and external variables in the abundance of these two pre-recruitment stages. Our results indicate that, during their first five months of life, cod, haddock, and herring experience higher density-dependent survival than capelin. The abundance of age-0 cod depends on the mean age and biomass of the spawning stock, a result which has implications for the management of the entire cod stock. Temperature is another important factor influencing the abundance at age-0 and age-1 of all four species, except herring at age-1. Between age-0 and age-1, there is an attenuation of density-dependent survival for cod and herring, while haddock and capelin experience density dependence at high and low temperatures, respectively. Predation by subadult cod is important for both capelin and cod at age-1. We found strong indications for interactions among the studied species, pointing to the importance of viewing the problem of species recruitment variability as a community, rather than as a population phenomenon.
PubMed ID
17503591 View in PubMed
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Evidence for a trade-off between early growth and tooth wear in Svalbard reindeer.

https://arctichealth.org/en/permalink/ahliterature84201
Source
J Anim Ecol. 2007 Nov;76(6):1139-48
Publication Type
Article
Date
Nov-2007
Author
Veiberg Vebjørn
Mysterud Atle
Bjørkvoll Eirin
Langvatn Rolf
Loe Leif Egil
Irvine R Justin
Bonenfant Christophe
Couweleers Fred
Stenseth Nils Chr
Author Affiliation
University Centre in Svalbard, Department of Arctic Biology, PB 156, N-9171 Longyearbyen, Norway, and Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo, Norway.
Source
J Anim Ecol. 2007 Nov;76(6):1139-48
Date
Nov-2007
Language
English
Publication Type
Article
Abstract
1. Ruminants depend on efficient physical degradation of forage through chewing to increase the surface area of the food particles presented to the microflora. Fossil evidence suggests that increased molar height is an adaptation for wear tolerance in dry ecosystems with sparse vegetation, but no study has shown selection pressure for hypsodonty in contemporary ruminants. 2. We explored the relationships between particle size in rumen, tooth wear (scanned molar occlusal topography), age and body mass of female Svalbard reindeer living in an arctic desert at 78 degrees latitude on Svalbard. 3. We predicted that (H1) if the rumen particle size is determined mainly by constraints due to tooth wear, and if tooth wear is mainly a function of age, average particle size in rumen should increase with age. From allometric relations it is known that larger individuals can survive on a lower-quality diet, we therefore predicted (H2) larger particle sizes with increases in (ln) body mass, irrespective of age and wear. Lastly, if there is a trade-off between growth and tooth wear in dry ecosystems (a selection pressure for hypsodonty), we predicted (H3) that teeth of heavier animals should be more worn than those of lighter animals of the same age. 4. The proportion of small particles (
PubMed ID
17922710 View in PubMed
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Food web dynamics affect Northeast Arctic cod recruitment.

https://arctichealth.org/en/permalink/ahliterature79005
Source
Proc Biol Sci. 2007 Mar 7;274(1610):661-9
Publication Type
Article
Date
Mar-7-2007
Author
Hjermann Dag Ø
Bogstad Bjarte
Eikeset Anne Maria
Ottersen Geir
Gjøsaeter Harald
Stenseth Nils Chr
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1050, Blindern, 0316 Oslo, Norway.
Source
Proc Biol Sci. 2007 Mar 7;274(1610):661-9
Date
Mar-7-2007
Language
English
Publication Type
Article
Keywords
Animals
Atlantic Ocean
Feeding Behavior - physiology
Fisheries - statistics & numerical data
Food chain
Gadus morhua - growth & development
Models, Theoretical
Osmeriformes
Temperature
Abstract
Proper management of ecosystems requires an understanding of both the species interactions as well as the effect of climate variation. However, a common problem is that the available time-series are of different lengths. Here, we present a general approach for studying the dynamic structure of such interactions. Specifically, we analyse the recruitment of the world's largest cod stock, the Northeast Arctic cod. Studies based on data starting in the 1970-1980s indicate that this stock is affected by temperature through a variety of pathways. However, the value of such studies is somewhat limited by the fact that they are based on a quite specific ecological and climatic situation. Recently, this stock has consisted of fairly young fish and the spawning stock has consisted of relatively few age groups. In this study, we develop a model for the effect of capelin (the cod's main prey) and herring on cod recruitment since 1973. Based on this model, we analyse data on cod, herring and temperature going back to 1921 and find that food-web effects explain a significant part of the cod recruitment variation back to around 1950.
PubMed ID
17254990 View in PubMed
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Importance of climatological downscaling and plant phenology for red deer in heterogeneous landscapes.

https://arctichealth.org/en/permalink/ahliterature83148
Source
Proc Biol Sci. 2005 Nov 22;272(1579):2357-64
Publication Type
Article
Date
Nov-22-2005
Author
Pettorelli Nathalie
Mysterud Atle
Yoccoz Nigel G
Langvatn Rolf
Stenseth Nils Chr
Author Affiliation
Department of Biology, University of Oslo, Centre for Ecological and Evolutionary Synthesis, (CEES) PO Box 1066, Blindern, N-0316 Oslo, Norway.
Source
Proc Biol Sci. 2005 Nov 22;272(1579):2357-64
Date
Nov-22-2005
Language
English
Publication Type
Article
Keywords
Animal Migration
Animals
Body Weight
Climate
Cold Climate
Deer - physiology
Ecosystem
Feeding Behavior
Norway
Plants - growth & development
Rain
Seasons
Snow
Abstract
Understanding how climate influences ecosystems represents a challenge in ecology and natural resource management. Although we know that climate affects plant phenology and herbivore performances at any single site, no study has directly coupled the topography-climate interaction (i.e. the climatological downscaling process) with large-scale vegetation dynamics and animal performances. Here we show how climatic variability (measured by the North Atlantic oscillation 'NAO') interacts with local topography in determining the vegetative greenness (as measured by the normalized difference vegetation index 'NDVI') and the body masses and seasonal movements of red deer (Cervus elaphus) in Norway. Warm springs induced an earlier onset of vegetation, resulting in earlier migration and higher body masses. Increasing values of the winter-NAO corresponded to less snow at low altitude (warmer, more precipitation results in more rain), but more snow at high altitude (colder, more precipitation corresponds to more snow) relative to winters with low winter-NAO. An increasing NAO thus results in a spatially more variable phenology, offering migrating deer an extended period with access to high-quality forage leading to increased body mass. Our results emphasize the importance of incorporating spring as well as the interaction between winter climate and topography when aiming at understanding how plant and animal respond to climate change.
PubMed ID
16243701 View in PubMed
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Linking climate change to lemming cycles.

https://arctichealth.org/en/permalink/ahliterature91357
Source
Nature. 2008 Nov 6;456(7218):93-7
Publication Type
Article
Date
Nov-6-2008
Author
Kausrud Kyrre L
Mysterud Atle
Steen Harald
Vik Jon Olav
Østbye Eivind
Cazelles Bernard
Framstad Erik
Eikeset Anne Maria
Mysterud Ivar
Solhøy Torstein
Stenseth Nils Chr
Author Affiliation
Centre for Ecological and Evolutionary Synthesis, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo, Norway.
Source
Nature. 2008 Nov 6;456(7218):93-7
Date
Nov-6-2008
Language
English
Publication Type
Article
Keywords
Animals
Arvicolinae - physiology
Birds - physiology
Ecosystem
Greenhouse Effect
History, 20th Century
History, 21st Century
Humidity
Models, Biological
Norway
Population Dynamics
Seasons
Snow
Temperature
Abstract
The population cycles of rodents at northern latitudes have puzzled people for centuries, and their impact is manifest throughout the alpine ecosystem. Climate change is known to be able to drive animal population dynamics between stable and cyclic phases, and has been suggested to cause the recent changes in cyclic dynamics of rodents and their predators. But although predator-rodent interactions are commonly argued to be the cause of the Fennoscandian rodent cycles, the role of the environment in the modulation of such dynamics is often poorly understood in natural systems. Hence, quantitative links between climate-driven processes and rodent dynamics have so far been lacking. Here we show that winter weather and snow conditions, together with density dependence in the net population growth rate, account for the observed population dynamics of the rodent community dominated by lemmings (Lemmus lemmus) in an alpine Norwegian core habitat between 1970 and 1997, and predict the observed absence of rodent peak years after 1994. These local rodent dynamics are coherent with alpine bird dynamics both locally and over all of southern Norway, consistent with the influence of large-scale fluctuations in winter conditions. The relationship between commonly available meteorological data and snow conditions indicates that changes in temperature and humidity, and thus conditions in the subnivean space, seem to markedly affect the dynamics of alpine rodents and their linked groups. The pattern of less regular rodent peaks, and corresponding changes in the overall dynamics of the alpine ecosystem, thus seems likely to prevail over a growing area under projected climate change.
Notes
Comment In: Nature. 2008 Nov 6;456(7218):43-418987726
PubMed ID
18987742 View in PubMed
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Mushroom fruiting and climate change.

https://arctichealth.org/en/permalink/ahliterature95561
Source
Proc Natl Acad Sci U S A. 2008 Mar 11;105(10):3811-4
Publication Type
Article
Date
Mar-11-2008
Author
Kauserud Håvard
Stige Leif Christian
Vik Jon Olav
Okland Rune H
Høiland Klaus
Stenseth Nils Chr
Author Affiliation
Microbial Evolution Research Group and Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, P.O. Box 1066 Blindern, NO-0316 Oslo, Norway.
Source
Proc Natl Acad Sci U S A. 2008 Mar 11;105(10):3811-4
Date
Mar-11-2008
Language
English
Publication Type
Article
Keywords
Agaricales - physiology
Climate
Fruiting Bodies, Fungal - physiology
Geography
Norway
Seasons
Time Factors
Abstract
Many species of fungi produce ephemeral autumnal fruiting bodies to spread and multiply. Despite their attraction for mushroom pickers and their economic importance, little is known about the phenology of fruiting bodies. Using approximately 34,500 dated herbarium records we analyzed changes in the autumnal fruiting date of mushrooms in Norway over the period 1940-2006. We show that the time of fruiting has changed considerably over this time period, with an average delay in fruiting since 1980 of 12.9 days. The changes differ strongly between species and groups of species. Early-fruiting species have experienced a stronger delay than late fruiters, resulting in a more compressed fruiting season. There is also a geographic trend of earlier fruiting in the northern and more continental parts of Norway than in more southern and oceanic parts. Incorporating monthly precipitation and temperature variables into the analyses provides indications that increasing temperatures during autumn and winter months bring about significant delay of fruiting both in the same year and in the subsequent year. The recent changes in autumnal mushroom phenology coincide with the extension of the growing season caused by global climate change and are likely to continue under the current climate change scenario.
PubMed ID
18310325 View in PubMed
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Northeast Arctic cod population persistence in the Lofoten-Barents Sea system under fishing.

https://arctichealth.org/en/permalink/ahliterature86702
Source
Ecol Appl. 2008 Apr;18(3):662-9
Publication Type
Article
Date
Apr-2008
Author
Durant Joël M
Hjermann Dag O
Sabarros Philippe S
Stenseth Nils Chr
Author Affiliation
Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, P.O. Box 1066 Blindern, 0316 Oslo, Norway.
Source
Ecol Appl. 2008 Apr;18(3):662-9
Date
Apr-2008
Language
English
Publication Type
Article
Abstract
Population growth, and hence the population's persistence, is affected by several factors such as climate, species interaction, and harvesting pressure. Proper resource management requires an understanding of these factors. We apply techniques based upon age-structured population matrices to analyze estimated stock sizes derived from annual bottom trawl sampling in the winter feeding area of northeast Arctic cod (Gadus morhua L.) from 1981 to 2003. We run generalized additive models to explain population growth rate by different explanatory variables. Cod population growth was found to be positively related to the abundance of capelin (Mallotus villosus Miller), negatively related to the number of cannibalistic cod with a two-year lag, and marginally positively related to the winter North Atlantic Oscillation index (NAO). This model remains true independently from the population status (i.e., fished or non-fished). Capelin abundance is the main variable that to some degree can be adjusted in order to maintain the population size at a given level of cod harvesting. Our results point to the importance of managing conjointly cod and capelin stocks.
PubMed ID
18488625 View in PubMed
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Plague dynamics are driven by climate variation.

https://arctichealth.org/en/permalink/ahliterature95709
Source
Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13110-5
Publication Type
Article
Date
Aug-29-2006
Author
Stenseth Nils Chr
Samia Noelle I
Viljugrein Hildegunn
Kausrud Kyrre Linné
Begon Mike
Davis Stephen
Leirs Herwig
Dubyanskiy V M
Esper Jan
Ageyev Vladimir S
Klassovskiy Nikolay L
Pole Sergey B
Chan Kung-Sik
Author Affiliation
Department of Biology, Centre for Ecological and Evolutionary Synthesis, University of Oslo, P.O. Box 1066, Blindern, 0316 Oslo, Norway. n.c.stenseth@bio.uio.no
Source
Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13110-5
Date
Aug-29-2006
Language
English
Publication Type
Article
Keywords
Animals
Climate
Gerbillinae - microbiology
Humans
Kazakhstan - epidemiology
Likelihood Functions
Plague - epidemiology - microbiology - veterinary
Prevalence
Seasons
Yersinia pestis - isolation & purification - physiology
Abstract
The bacterium Yersinia pestis causes bubonic plague. In Central Asia, where human plague is still reported regularly, the bacterium is common in natural populations of great gerbils. By using field data from 1949-1995 and previously undescribed statistical techniques, we show that Y. pestis prevalence in gerbils increases with warmer springs and wetter summers: A 1 degrees C increase in spring is predicted to lead to a >50% increase in prevalence. Climatic conditions favoring plague apparently existed in this region at the onset of the Black Death as well as when the most recent plague pandemic arose in the same region, and they are expected to continue or become more favorable as a result of climate change. Threats of outbreaks may thus be increasing where humans live in close contact with rodents and fleas (or other wildlife) harboring endemic plague.
PubMed ID
16924109 View in PubMed
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18 records – page 1 of 2.