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  • 1. Abalaka, J. L.
    et al.
    Ottosson, Ulf
    Tende, Talatu
    Larson, Keith W.
    Rock Firefinch Lagonosticta sanguinodorsalis in the Mandara Mountains, north-east Nigeria: a new subspecies?2010Ingår i: African Bird Club Bulletin, ISSN 1352-481X, Vol. 17, nr 2, s. 210-211Artikel i tidskrift (Refereegranskat)
    Abstract [fr]

    L’Amarante des rochers Lagonosticta sanguinodorsalis dans les Monts Mandara, Nigeria du sud-est: une nouvelle sous-espèce ? Nous fournissons une description d’un mâle et d’une femelle, ainsi que desphotos d’un mâle, d’un amarante capturé dans les Monts Mandara, au nord-est du Nigeria. Le plumage et le cri de cet amarante sont identiques à ceux de l’Amarante des rochers Lagonosticta sanguinodorsalis, une espèce précédemment rapportée de la zone, excepté que le mâle n’a pas la couronne grise typique de l’espèce. Des travaux supplémentaires sur le terrain sont nécessaires pour déterminer s’il agit d’un individu aberrant ou d’une population de l’Amarante des rochers morphologiquement distincte.

  • 2.
    Aksnes, Dag W.
    et al.
    Nordic Institute for Studies in Innovation, Research & Education (NIFU), Norway.
    Blöcker, Christopher
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Colliander, Cristian
    Umeå universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen. Umeå universitet, Umeå universitetsbibliotek (UB).
    Nilsson, Lena Maria
    Umeå universitet, Arktiskt centrum vid Umeå universitet (Arcum). Umeå universitet, Medicinska fakulteten, Institutionen för epidemiologi och global hälsa.
    Kullerud, Lars (Medarbetare/bidragsgivare)
    UArctic.
    Larson, Keith (Medarbetare/bidragsgivare)
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    SCITE team, (Medarbetare/bidragsgivare)
    Arctic Research Trends: Bibliometrics 2016-20222023Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This work was conducted by the UArctic Thematic Network on Research Analytics and Bibliometrics. It was supported by Global Affairs Canada through the Global Arctic Leadership Initiative.

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  • 3.
    Aksnes, Dag W.
    et al.
    Nordic Institute for Studies in Innovation, Research & Education (NIFU), Norway.
    Danell, Rickard
    Umeå universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    Kullerud, Lars
    University of the Arctic (UArctic).
    Nilsson, Lena Maria
    Umeå universitet, Arktiskt centrum vid Umeå universitet (Arcum). Umeå universitet, Medicinska fakulteten, Institutionen för epidemiologi och global hälsa.
    Larson, Keith (Medarbetare/bidragsgivare)
    Umeå universitet, Arktiskt centrum vid Umeå universitet (Arcum).
    Diane, Hirshberg (Redaktör)
    Institute of Social and Economic Research, University of Alaska Anchorage, United States.
    Arctic research trends: external funding 2016-20222024Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report aims to provide an update to the two studies published in 2016 and 2017 (Osipov et al 2016 & 2017) with the primary task of assessing the global funding landscape around Arctic-related research. While the previous reports were focusing on the periods 2006-2015 and 2007-2016 respectively, this report covers 2016 to 2022, using the funding data from the Dimensions[1] dataset, which includes information from more than 600 funders and 7 million awarded grants with funding totalling $2.4 trillion+ (in US Dollars).

    The key findings of the updated report, based on the available data, highlight the following trends:  

    ·       The fields of Earth Sciences (10.3 percent) and Environmental Science (5.5 percent) are the two largest recipients of Arctic research funding. 

    ·       The US is the largest Arctic research nation in terms of total spending and number of projects started. It also has the most comprehensive coverage of funding sources in the dataset.  

    ·       Canada and Russia are the second and third largest nations in terms of number of projects started, followed by Norway and Sweden.

    ·       UArctic institutions are central actors in Arctic research globally. 

    ·       Researchers from Arctic Council Observer nations are financing a substantial amount of research on the Arctic. In particular, the UK and Japan finance a significant number of projects, followed by Germany and China with considerable numbers of Arctic-related research projects.

    ·       Funding from the European Union holds the position of the eighth-largest funder based on the number of projects awarded. The European Union is characterized by a few projects with large funding.

    ·       The analysis suggests that there is neither growth nor shrinkage in the relative volume of Arctic research funding over the period 2016–2022 in comparison with the growth of the general scientific community.

    ·       Private funders and foundations contribute little to Arctic research. Only one percent of the projects starting in 2016–2022 were funded privately. 

    In general, the largest sources of external public funding for Arctic research come from the United States (US), Russia, Canada, and Norway, with the US being the biggest net contributor. Other kinds of funding, such as base budgets, are not described in this report. In addition, data on the public funding and funding amounts of Arctic research in Russia, Canada, and the Kingdom of Denmark are not always provided by the funders in project profiles, and net value is sometimes not disclosed by the funders themselves. 

    This report specifically investigates projects initiated between 2016 and 2022, providing insights into the contemporary funding landscape of Arctic research. Understanding the geographical and institutional distribution of funding, as well as the specific areas of focus within this funding, holds significance for UArctic and Arctic Council officials. Such insights facilitate their ability to offer informed guidance to their respective members, aiding in the identification of strategic priorities.

    Moreover, gaining insights into the entities funding Arctic research, and those not engaged in such funding, holds importance for UArctic and Arctic Council science officers. Armed with information about Arctic-focused endeavours they can engage with funding bodies, fostering dialogue aimed at enhancing support, and collaboration for such initiatives.

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  • 4. Berdan, Emma
    et al.
    Rosenquist, Hanna
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Wellenreuther, Maren
    Inversion frequencies and phenotypic effects are modulated by the environment: insights from a reciprocal transplant study in Coelopa frigida2018Ingår i: Evolutionary Ecology, ISSN 0269-7653, E-ISSN 1573-8477, Vol. 32, nr 6, s. 683-698Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding how environmental variation drives phenotypic diversification within species is a major objective in evolutionary biology. The seaweed fly Coelopa frigida provides an excellent model for the study of genetically driven phenotypes because it carries an α/β inversion polymorphism that affects body size. Coelopa frigida inhabits highly variable beds of decomposing seaweed on the coast in Scandinavia thus providing a suitable test ground to investigate the genetic effects of substrate on both the frequency of the inversion (directional selection) and on the phenotype (genotype × environment effects). Here we use a reciprocal transplant experiment to test the effect of the α/β inversion on body size traits and development time across four suitable natural breeding substrates from the clinal distribution. We show that while development time is unaffected by G × E effects, both the frequency of the inversion and the relative phenotypic effects of the inversion on body size differ between population × substrate combinations. This indicates that the environment modulates the fitness as well as the phenotypic effects of the inversion karyotypes. It further suggests that the inversion may have accumulated qualitatively different mutations in different populations that interact with the environment. Together our results are consistent with the idea that the inversion in C. frigida likely evolves via a combination of local mutation, G × E effects, and differential fitness of inversion karyotypes in heterogeneous environments.

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  • 5.
    Cantwell-Jones, Aoife
    et al.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ward, Alan
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Bates, Olivia K.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Cox, Tara
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Gibbons, Charlotte
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Richardson, Ryan
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Al-Hayali, Abdullah M. R.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Svedin, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Aronsson, Max
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brannlund, Frida
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Tylianakis, Jason M.
    Bioprotection Aotearoa, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.
    Johansson, Jacob
    Department of Biology, Lund University, Lund, Sweden.
    Gill, Richard J.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Imperial College London, London, United Kingdom.
    Mapping trait versus species turnover reveals spatiotemporal variation in functional redundancy and network robustness in a plant-pollinator community2023Ingår i: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 37, nr 3, s. 748-762Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Functional overlap among species (redundancy) is considered important in shaping competitive and mutualistic interactions that determine how communities respond to environmental change. Most studies view functional redundancy as static, yet traits within species—which ultimately shape functional redundancy—can vary over seasonal or spatial gradients. We therefore have limited understanding of how trait turnover within and between species could lead to changes in functional redundancy or how loss of traits could differentially impact mutualistic interactions depending on where and when the interactions occur in space and time. Using an Arctic bumblebee community as a case study, and 1277 individual measures from 14 species over three annual seasons, we quantified how inter- and intraspecific body-size turnover compared to species turnover with elevation and over the season. Coupling every individual and their trait with a plant visitation, we investigated how grouping individuals by a morphological trait or by species identity altered our assessment of network structure and how this differed in space and time. Finally, we tested how the sensitivity of the network in space and time differed when simulating extinction of nodes representing either morphological trait similarity or traditional species groups. This allowed us to explore the degree to which trait-based groups increase or decrease interaction redundancy relative to species-based nodes. We found that (i) groups of taxonomically and morphologically similar bees turn over in space and time independently from each other, with trait turnover being larger over the season; (ii) networks composed of nodes representing species versus morphologically similar bees were structured differently; and (iii) simulated loss of bee trait groups caused faster coextinction of bumblebee species and flowering plants than when bee taxonomic groups were lost. Crucially, the magnitude of these effects varied in space and time, highlighting the importance of considering spatiotemporal context when studying the relative importance of taxonomic and trait contributions to interaction network architecture. Our finding that functional redundancy varies spatiotemporally demonstrates how considering the traits of individuals within networks is needed to understand the impacts of environmental variation and extinction on ecosystem functioning and resilience. Read the free Plain Language Summary for this article on the Journal blog.

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  • 6.
    Cantwell-Jones, Aoife
    et al.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, United Kingdom.
    Tylianakis, Jason M.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, United Kingdom; Bioprotection Aotearoa, School of Biological Sciences, Private Bag 4800, University of Canterbury, Christchurch, New Zealand.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Gill, Richard J.
    Georgina Mace Centre for The Living Planet, Department of Life Sciences, Silwood Park, Imperial College London, Ascot, United Kingdom.
    Using individual-based trait frequency distributions to forecast plant-pollinator network responses to environmental change2024Ingår i: Ecology Letters, ISSN 1461-023X, E-ISSN 1461-0248, Vol. 27, nr 1, artikel-id e14368Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Determining how and why organisms interact is fundamental to understanding ecosystem responses to future environmental change. To assess the impact on plant-pollinator interactions, recent studies have examined how the effects of environmental change on individual interactions accumulate to generate species-level responses. Here, we review recent developments in using plant-pollinator networks of interacting individuals along with their functional traits, where individuals are nested within species nodes. We highlight how these individual-level, trait-based networks connect intraspecific trait variation (as frequency distributions of multiple traits) with dynamic responses within plant-pollinator communities. This approach can better explain interaction plasticity, and changes to interaction probabilities and network structure over spatiotemporal or other environmental gradients. We argue that only through appreciating such trait-based interaction plasticity can we accurately forecast the potential vulnerability of interactions to future environmental change. We follow this with general guidance on how future studies can collect and analyse high-resolution interaction and trait data, with the hope of improving predictions of future plant-pollinator network responses for targeted and effective conservation.

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  • 7. Collis, Ken
    et al.
    Roby, Daniel D.
    Larson, Keith W.
    Department of Fisheries and Wildlife, 104 Nash Hall, Oregon State University, Corvallis, OR, 97331, USA; Evolutionary Ecology, Lund University, Sølvegatan 37, 223 62 Lund, Sweden.
    Adrean, Lindsay J.
    Nelson, S. Kim
    Evans, Allen F.
    Hostetter, Nathan
    Battaglia, Dan
    Lyons, Donald E.
    Marcella, Tim
    Patterson, Allison
    Trends in Caspian Tern Nesting and Diet in San Francisco Bay: Conservation Implications for Terns and Salmonids2012Ingår i: Waterbirds (De Leon Springs, Fla.), ISSN 1524-4695, E-ISSN 1938-5390, Vol. 35, nr 1, s. 25-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Colony size, nesting ecology and diet of Caspian Terns (Hydroprogne caspia) were investigated in the San Francisco Bay area (SFBA) during 2003-2009 to assess the potential for conservation of the tern breeding population and possible negative effects of predation on survival of juvenile salmonids (Oncorhyn-chusspp.). Numbers of breeding Caspian Terns declined 36% from 2003 to 2009, mostly due to abandonment of the Knight Island colony and decline of the Brooks Island colony, the two largest colonies in the SFBA. Concurrently, nesting success declined 69% associated with colony site characteristics such as (a) quality and quantity of nesting substrate, (b) vulnerability to nest predators, (c) displacement by other colonial waterbirds and (d) human disturbance. Marine fishes were the predominant prey in tern diets from the SFBA; however, diet composition varied among colonies. Juvenile salmonids comprised 22.9% of the diet of terns nesting in the North Bay, 5.3% of diet of terns nesting in the Central Bay, and 0.1% in the South Bay. Construction or restoration of nesting islands in the South Bay may help maintain and restore breeding Caspian Terns without enhancing mortality of salmonid stocks of conservation concern.

  • 8. Craig, David P.
    et al.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Klamath Bird Observatory, 320 Beach Street, Ashland, Oregon, 97520, USA.
    Migratory Connectivity of North American Caspian Tern (Hydroprogne caspia) Populations2017Ingår i: Waterbirds (De Leon Springs, Fla.), ISSN 1524-4695, E-ISSN 1938-5390, Vol. 40, nr 1, s. 58-62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Migratory connectivity of Caspian Terns (Hydroprogne caspia) was investigated using individuals marked in North America between 1922 and 2015. The results support recent genetic work describing three breeding regions (Pacific, Great Lakes, and Central Canada). Further., our results show strong migratory connectivity of Pacific breeders to wintering regions in central and western Mexico, and connectivity of Great Lakes breeders to wintering regions in the Gulf of Mexico and Caribbean. This integrated picture of demographic connectivity throughout North America should help in planning more effective management of the species.

  • 9. De Ruyck, Chris
    et al.
    Hobson, Keith A.
    Koper, Nicola
    Larson, Keith W.
    Wassenaar, Leonard I.
    An Appraisal of the Use of Hydrogen-Isotope Methods to Delineate Origins of Migratory Saw-whet Owls in North America2013Ingår i: The Condor, ISSN 00105422, 1938-5129, Vol. 115, nr 2, s. 366-374Artikel i tidskrift (Refereegranskat)
  • 10. Fritsch, Peter W.
    et al.
    Schiller, Anja M.
    Larson, Keith W.
    Department of Animal Ecology, Lund University, Sölvegatan 37, Lund 22362, Sweden .
    Taxonomic Implications of Morphological Variation in Cercis canadensis (Fabaceae) from Mexico and Adjacent Parts of Texas2009Ingår i: Systematic Botany, ISSN 0363-6445, E-ISSN 1548-2324, Vol. 34, nr 3, s. 510-520Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Taxonomic treatments recognize three varieties of Cercis canadensis: with variety canadensis, widespread throughout the eastern United States, and varieties texensis and mexicana, found east and west of the Pecos River in Texas, respectively. The distribution of Cercis continues southward into northeastern Mexico, but complex variation in leaf shape has confounded straightforward application of varietal names to the Mexican plants. To clarify the taxonomy of Cercis in Mexico, we conducted a morphometric analysis with 281 herbarium specimens, including a representative set of samples from Texas. Correlation and principal component analysis of 12 characters recovered two groups that correspond to the presence versus absence of branchlet pubescence. These groups are geographically distinct at the northern and southern extremes of the focus area but exhibit a large central region of overlap. No other discontinuities in character states were discovered to corroborate this division. Leaf shape varies continuously from ovate-acuminate at the northern and southern extremes to subreniform in the central region, suggesting clinal adaptation to the mesic versus xeric environments in which the plants occur. Based on our data, we apply the varietal epithets mexicana and, provisionally, texensis to Mexican C. canadensis with pubescent and glabrous branchlets, respectively, the latter based on geographic proximity to plants in Texas in the absence of definitive evidence on the phenotypic distinction between varieties canadensis and texensis.

  • 11. Hobson, Keith A.
    et al.
    Van Wilgenburg, Steven L.
    Larson, Keith W.
    Environment Canada, Saskatoon, Saskatchewan, Canada.
    Wassenaar, Leonard I.
    A feather hydrogen isoscape for Mexico2009Ingår i: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 102, nr 3, s. 167-174Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Developing useful biological isoscapes for areas of the world is a priority. This is the case for Mexico that hosts a large percentage of North America's Neotropical migrant birds. Here we investigated the use of House Sparrow (Passer domesticus) feathers to create a spatially explicit feather deuterium isoscape for that country using samples (n = 461) that were collected across Mexico. Considerable and useful spatial hydrogen isotopic structure was observed, suggesting that isotopes may be a potential forensic tool for evaluating origins of Mexican derived fauna and flora. The most positive feather [delta]D values occurred in the northeast and most negative in the south-central part of the country, roughly matching [delta]D patterns observed in groundwater. A weak negative isotopic relationship was found with altitude in both the Pacific and Atlantic drainage systems. The most parsimonious model describing isotopic spatial variation in feathers between 300 and 3000 m a.s.l. included groundwater [delta]D ([delta]Dgw; precipitation proxy), sex, amount of precipitation, and the coefficient of variation in amount of precipitation. Overall, [delta]Dgw was a poor predictor of sparrow [delta]Df values for all of Mexico. However, this relationship was considerably strengthened when we considered sex separately, removed the Baja peninsula from our sample, and considered the Atlantic and Pacific drainage basins separately. The strongest relationship between [delta]Dgw and [delta]Df was found for female sparrows in the Atlantic drainage basin (r2 = 0.464). We recommend that researchers interested in inferring origins of migratory birds and other animals in Mexico create species specific isotopic basemaps that may be guided by the isotopic patterns we have observed for House Sparrows and groundwater.

  • 12. Hobson, Keith A.
    et al.
    Van Wilgenburg, Steven L.
    Wassenaar, Leonard I.
    Larson, Keith W.
    Department of Zoology, Lund University, Lund, Scania, Sweden.
    Linking Hydrogen (δ2H) Isotopes in Feathers and Precipitation: sources of Variance and Consequences for Assignment to Isoscapes2012Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 7, nr 4, artikel-id e35137Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tracking small migrant organisms worldwide has been hampered by technological and recovery limitations and sampling bias inherent in exogenous markers. Naturally occurring stable isotopes of H (δ2H) in feathers provide an alternative intrinsic marker of animal origin due to the predictable spatial linkage to underlying hydrologically driven flow of H isotopes into foodwebs. This approach can assess the likelihood that a migrant animal originated from a given location(s) within a continent but requires a robust algorithm linking H isotopes in tissues of interest to an appropriate hydrological isotopic spatio-temporal pattern, such as weighted-annual rainfall. However, a number of factors contribute to or alter expected isotopic patterns in animals. We present results of an extensive investigation into taxonomic and environmental factors influencing feather δ2H patterns across North America. Stable isotope data were measured from 544 feathers from 40 species and 140 known locations. For δ2H, the most parsimonious model explaining 83% of the isotopic variance was found with amount-weighted growing-season precipitation δ2H, foraging substrate and migratory strategy. This extensive H isotopic analysis of known-origin feathers of songbirds in North America and elsewhere reconfirmed the strong coupling between tissue δ2H and global hydrologic δ2H patterns, and accounting for variance associated with foraging substrate and migratory strategy, can be used in conservation and research for the purpose of assigning birds and other species to their approximate origin.

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  • 13.
    Hostens, Lore
    et al.
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    Van Meerbeek, Koenraad
    Department Earth of Environmental Science, KU Leuven, Leuven, Belgium; KU Leuven Plant Institute, KU Leuven, Leuven, Belgium.
    Wiegmans, Dymphna
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lenoir, Jonathan
    UMR CNRS 7058, Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN), Université de Picardie Jules Verne, Amiens, France.
    Clavel, Jan
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    Wedegärtner, Ronja
    Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway.
    Pirée, Amber
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    Nijs, Ivan
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    Lembrechts, Jonas J.
    Research Group Plants and Ecosystems (PLECO), University of Antwerp, Antwerp, Belgium.
    The drivers of dark diversity in the Scandinavian mountains are metric-dependent2023Ingår i: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 34, nr 6, artikel-id e13212Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Question: Dark diversity refers to the set of species that are not observed in an area but could potentially occur based on suitable local environmental conditions. In this paper, we applied both niche-based and co-occurrence-based methods to estimate the dark diversity of vascular plant species in the subarctic mountains. We then aimed to unravel the drivers explaining (a) why some locations were missing relatively more suitable species than others, and (b) why certain plant species were more often absent from suitable locations than others.

    Location: The Scandinavian mountains around Abisko, northern Sweden.

    Methods: We calculated the dark diversity in 107 plots spread out across four mountain trails using four different methods: two co-occurrence-based (Beals’ index and the hypergeometric method) and two niche-based (the climatic niche model and climatic niche model followed by species-specific threshold). We then applied multiple Generalized Linear Mixed-Effects Models and General Linear Models to determine which habitat characteristics and species traits contributed the most to dark diversity.

    Results: The study showed a notable divergence in the predicted drivers of dark diversity depending on the method used. Nevertheless, we can conclude that plot-level dark diversity was generally 17% higher in areas at low elevations and 31% higher in areas with a low species richness.

    Conclusion: Our findings call for caution when interpreting statistical findings of dark-diversity estimates. Even so, all analyses point toward an important role for natural processes such as competitive dominance as the main driver of the spatial patterns found in dark diversity in the northern Scandes.

  • 14. Inserillo, Daniel R.
    et al.
    Reitsma, Leonard
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Smith, Joseph
    Camacho, M. Alejandra
    Transient Swainson's Thrush (Catharus Ustulatus) Wintering In The Andean Foothills of Ecuador are Almost Exclusively Young Males2020Ingår i: Ornitologia Neotropical, ISSN 1075-4377, Vol. 31, s. 98-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We know relatively little about the non-breeding period of most migratory birds. Decades of research on Swainson’s Thrush (Catharus ustulatus) has focused on their breeding ecology, whereas their non-breeding ecology is limited to broad patterns of distribution and migratory stop-over ecology. For the nearly 50 years, the US Breeding Bird Survey recorded declines of 0.7% per year for the Russet-backed Swainson’s Thrush (C. u. swainsonii) subspecies, which spends the non-breeding period in South America. However, there is an insufficient understanding of the constraints across their annual cycle to determine reasons for the sustained decline. In 2013 and 2014, we examined their little studied non-breeding period on the Andean slopes of Ecuador where prior experience showed that they were seasonally abundant. Here rapid deforestation threatens primary forest. We used point counts and radio telemetry to evaluate whether primary forest was used preferentially to recently regenerated second-growth forest. From point counts, 76% of detections and almost all captured individuals occurred in secondary forest. Of 86 birds captured in mist nets, 85 were males and 83 young of the year, indicating a highly skewed ratio in favor of young males. Radio telemetry demonstrated preference for secondary forest, especially for fruiting Cecropia spp. trees, with no apparent territorial behavior by those tracked and with short residency times. A marked decrease in density over the course of the field season suggests an itinerant population possibly tracking the ephemeral use of fruit resources. Alternatively, these temporal and spatial patterns could suggest that this population undergoes a mid-winter intratropical migration or at least landscape-level movements. However, we observed thrushes throughout our extended sampling period suggesting transiency with high turnover. Together, this study documents demographic separation during the non-breeding period with preference for of secondary forest and high transiency, important findings in informing management across the annual cycle.

  • 15. Karczmarski, Leszek
    et al.
    Wursig, Bernd
    Gailey, Glenn
    Larson, Keith W.
    Midway Atoll National Wildlife Refuge, Pacific Remote Islands NWR Complex, U.S. Fish and Wildlife Service, Honolulu, USA.
    Vanderlip, Cynthia
    Spinner dolphins in a remote Hawaiian atoll: social grouping and population structure2005Ingår i: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 16, nr 4, s. 675-685Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spinner dolphins (Stenella longirostris) commonly use inshore island and atoll habitats for daytime rest and social interactions and forage over deep waters at night. In Hawaii, they occur throughout the archipelago. We applied photoidentification mark-recapture techniques to study the population structure of spinner dolphins associated with remote Midway Atoll, far-western Hawaii. At Midway, spinner dolphins live in stable bisexually bonded societies of long-term associates, with strong geographic fidelity, no obvious fission-fusion, and limited contacts with other populations. Their large cohesive groups change little over time and are behaviorally/socially discrete from other spinner dolphin groups. This social pattern differs considerably from the fluid fission-fusion model proposed previously for spinner dolphins associated with a large island habitat in the main Hawaiian Archipelago. These differences correspond to geographic separation and habitat variation. While in the main islands there are several daytime resting places available at each island habitat; in far-western Hawaii, areas of suitable habitat are limited and separated by large stretches of open pelagic waters with potentially high risk of shark predation. We hypothesize that with deepwater food resources in close proximity and other atolls relatively far away for easy (day-to-day) access, it is energetically more beneficial in the remote Hawaiian atolls to remain “at home” than to travel to other atolls, so there is stability instead of variability; there is no fission-fusion effect. Thus, the geographic isolation and small size of remote atolls trigger a process in which the fluidity of the fission-fusion spinner dolphin society is replaced with long-term group fidelity and social stability.

  • 16. Larson, Keith
    Hybrid zone dynamics, assortative mating, and migratory programmes in a willow warbler migratory divide2012Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis I will compare and contrast the two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) with differing migratory phenotypes (or "migratype") in the context of their migratory divide and hybrid zone in central Sweden. Their migratory programs differ in the direction and distance traveled during migration. The "northern" willow warblers migrate south-southeast through the Balkan Peninsula to winter in eastern Africa. The "southern" willow warbler migrates southwest through the Iberian Peninsula to winter in western Africa. In this thesis I will also explore the consequences of hybridization for these two very closely related subspecies where they meet in central Sweden. In the first paper I investigate the role of population abundance in determining the location of the hybrid zone. Specifically, is there a region of low abundance associated with the hybrid zone? Further, is the hybrid zone located on an environmental gradient which might suggest that breeding ground environmental conditions are responsible for the lower abundance? This lower abundance may reflect the unsuitability of habitats along the environmental gradient for either parental or hybrid offspring. In my second paper, I ask if there are population specific differences in their wintering moult ecology that can be elucidated from diet derived stable isotope patterns in their winter moulted primary flight feathers? The third paper addresses the important question, does assortative mating lead to reproductive isolation or do these very similar subspecies hybridize and produce offspring? In my fourth paper, I ask does local adaptation to environmental conditions, such as temperature extremes and the short growing season, in mountain populations of willow warblers explain the apparent distribution of the “northern-allele” for the AFLP derived genetic marker WW1? Finally, in the fifth paper, I conduct a detailed analysis of phenotypic traits at 50 sites across the hybrid zone, including 35 sites visited more than once. Here I ask, does lower abundances in the west of the hybrid zone predict the zone to be wider in the west than in the east? Further, using data from repeated visits to sites across the zone, we predict low repeatabilities for migratory associated traits that would suggest that high annual turn-over in migratypes occupying the zone. For future efforts to understand hybrid zone dynamics, it will be essential to develop genetic markers that allow one to separate each parental migratypes, hybrids, and back-crosses. Once genetic markers allow the identification of hybrid offspring, orientation experiments should be conducted to elucidate migratory directional preferences that would support our hypothesis that hybrids take an intermediate migratory direction to their parental migratypes. This intermediate direction could be a significant cost to hybrid fitness, as this route would require they cross the Mediterranean Sea and Sahara Desert at their widest points.

  • 17.
    Larson, Keith
    et al.
    Department of Animal Ecology, Lund University, Lund, Sweden; Klamath Bird Observatory, Ashland, USA.
    Hobson, Keith
    Assignment to breeding and wintering grounds using stable isotopes: a comment on lessons learned by Rocque et al.2009Ingår i: Journal of Ornithology, ISSN 2193-7192, E-ISSN 2193-7206, Vol. 150, nr 3, s. 709-712Artikel i tidskrift (Refereegranskat)
  • 18.
    Larson, Keith W.
    Lund University.
    Hybrid zone dynamics, assortative mating, and migratory programmes in a willow warbler migratory divide2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis I will compare and contrast the two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) with differing migratory phenotypes (or "migratype") in the context of their migratory divide and hybrid zone in central Sweden. Their migratory programs differ in the direction and distance traveled during migration. The "northern" willow warblers migrate south-southeast through the Balkan Peninsula to winter in eastern Africa. The "southern" willow warbler migrates southwest through the Iberian Peninsula to winter in western Africa. In this thesis I will also explore the consequences of hybridization for these two very closely related subspecies where they meet in central Sweden. In the first paper I investigate the role of population abundance in determining the location of the hybrid zone. Specifically, is there a region of low abundance associated with the hybrid zone? Further, is the hybrid zone located on an environmental gradient which might suggest that breeding ground environmental conditions are responsible for the lower abundance? This lower abundance may reflect the unsuitability of habitats along the environmental gradient for either parental or hybrid offspring. In my second paper, I ask if there are population specific differences in their wintering moult ecology that can be elucidated from diet derived stable isotope patterns in their winter moulted primary flight feathers? The third paper addresses the important question, does assortative mating lead to reproductive isolation or do these very similar subspecies hybridize and produce offspring? In my fourth paper, I ask does local adaptation to environmental conditions, such as temperature extremes and the short growing season, in mountain populations of willow warblers explain the apparent distribution of the “northern-allele” for the AFLP derived genetic marker WW1? Finally, in the fifth paper, I conduct a detailed analysis of phenotypic traits at 50 sites across the hybrid zone, including 35 sites visited more than once. Here I ask, does lower abundances in the west of the hybrid zone predict the zone to be wider in the west than in the east? Further, using data from repeated visits to sites across the zone, we predict low repeatabilities for migratory associated traits that would suggest that high annual turn-over in migratypes occupying the zone. For future efforts to understand hybrid zone dynamics, it will be essential to develop genetic markers that allow one to separate each parental migratypes, hybrids, and back-crosses. Once genetic markers allow the identification of hybrid offspring, orientation experiments should be conducted to elucidate migratory directional preferences that would support our hypothesis that hybrids take an intermediate migratory direction to their parental migratypes. This intermediate direction could be a significant cost to hybrid fitness, as this route would require they cross the Mediterranean Sea and Sahara Desert at their widest points.

  • 19.
    Larson, Keith W.
    et al.
    Willamette University, 900 State Street, Salem, Oregon 97301 USA.
    Craig, David P.
    Digiscoping Vouchers for Diet Studies in Bill-load Holding Birds2006Ingår i: Waterbirds (De Leon Springs, Fla.), ISSN 1524-4695, E-ISSN 1938-5390, Vol. 29, nr 2, s. 198-202Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We conducted an observer-based diet study of Caspian Terns (Sterna caspia) incorporating digiscoping to collect digital photographic vouchers of fish. Observer-based diet studies pose several problems, ranging from differential experience and abilities of observers to the lack of vouchers for confirming identification. One solution to these problems is to recover fish either directly from birds (i.e., trapping, shooting) or ones dropped on the colony. This may not, however, be desirable or achieve adequate sample sizes. Some species are difficult to capture or methods may cause significant disturbance and/or nest abandonment. To overcome these problems, we used a relatively inexpensive new photographic technique known as digiscoping. By holding a high-resolution point-and-shoot digital camera up to the eyepiece of a spotting scope or pair of binoculars, we could take digital photographic vouchers of fish as terns brought them into the colony. During the study, we made 16,423 observations, identifying 92% of the fish to the family (3%), genus (15%), or species (74%) level. We supported these observations with over 2,500 digital photograph vouchers. Vouchers confirmed identification of all fish taxa and allowed for later identification, by us or qualified fisheries biologists, of several species unidentifiable in the field. The ability to have independent experts confirm observations and identify previously unidentifiable observations greatly expanded our understanding of the range of fish taken by Caspian Terns.

  • 20.
    Larson, Keith W.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Kundisch, Sieglinde
    Attempted predation of Northern hawk-owl Surnia ullula by common kestrel Falco tinnunculus?: [Predationsförsök på hökuggla Surnia ulula av tornfalk Falco tinnunculus?]2014Ingår i: Ornis Svecica, ISSN 1102-6812, E-ISSN 2003-2633, Vol. 24, nr 3-4, s. 165-166Artikel i tidskrift (Refereegranskat)
  • 21.
    Larson, Keith W.
    et al.
    Department of Biology, Lund University, Lund, Sweden.
    Kundisch, Sieglinde
    Department of Biology, Lund University, Lund, Sweden.
    Willow warbler Phylloscopus trochilus nesting in a juniper during a peak lemming year2012Ingår i: Ornis Svecica, ISSN 1102-6812, E-ISSN 2003-2633, Vol. 22, nr 3-4, s. 141-143Artikel i tidskrift (Refereegranskat)
  • 22.
    Larson, Keith W.
    et al.
    Department of Biology, Centre for Animal Movement Research, Lund University, Lund, Sweden.
    Liedvogel, Miriam
    Addison, BriAnne
    Kleven, Oddmund
    Laskemoen, Terje
    Lifjeld, Jan T.
    Lundberg, Max
    Åkesson, Susanne
    Bensch, Staffan
    Allelic Variation in a Willow Warbler Genomic Region Is Associated with Climate Clines2014Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 9, nr 5, artikel-id e95252Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Local adaptation is an important process contributing to population differentiation which can occur in continuous or isolated populations connected by various amounts of gene flow. The willow warbler (Phylloscopus trochilus) is one of the most common songbirds in Fennoscandia. It has a continuous breeding distribution where it is found in all forested habitats from sea level to the tree line and therefore constitutes an ideal species for the study of locally adapted genes associated with environmental gradients. Previous studies in this species identified a genetic marker (AFLP-WW1) that showed a steep north-south cline in central Sweden with one allele associated with coastal lowland habitats and the other with mountainous habitats. It was further demonstrated that this marker is embedded in a highly differentiated chromosome region that spans several megabases. In the present study, we sampled 2,355 individuals at 128 sites across all of Fennoscandia to study the geographic and climatic variables associated with the allele frequency distributions of WW1. Our results demonstrate that 1) allele frequency patterns significantly differ between mountain and lowland populations, 2) these allele differences coincide with extreme temperature conditions and the short growing season in the mountains, and milder conditions in coastal areas, and 3) the northern-allele or "altitude variant" of WW1 occurs in willow warblers that occupy mountainous habitat regardless of subspecies. Finally these results suggest that climate may exert selection on the genomic region associated with these alleles and would allow us to develop testable predictions for the distribution of the genetic marker based on climate change scenarios.

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  • 23.
    Larson, Keith W.
    et al.
    Dept of Biology, Centre for Animal Movement Research, Lund University, Lund, Sweden.
    Liedvogel, Miriam
    Bensch, Staffan
    Åkesson, Susanne
    Wassenaar, Leonard I.
    Hobson, Keith A.
    Inferring the ecology of willow warblers during their winter moult by sequential stable isotope analyses of remiges2013Ingår i: Journal of Avian Biology, ISSN 0908-8857, E-ISSN 1600-048X, Vol. 44, nr 6, s. 561-566Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a comparison of feather stable isotope (δ13C, δ15N) patterns representing the habitat and diet conditions for two subspecies of willow warblers Phylloscopus trochilus that breed in parapatry, but winter in different regions of sub-Saharan Africa. Previous analyses have shown that on average winter moulted innermost primaries (P1) show subspecific differences in δ15N values, although individuals show substantial variation for both δ13C and δ15N within the subspecies. We examined whether corresponding variation in the timing of the winter moult, as reflected by consistent intra-wing correlations for individual's δ13C and δ15N values, could explain some of the previously observed isotopic variation. Further, differential subspecific adaptations to winter precipitation patterns across Africa might result in a variable degree of site fidelity or itinerancy during moult. We found no consistent trend in isotopic values from innermost to outermost primaries, thus inter-individual variation in the timing of moult does not explain the subspecific isotopic variation for P1. Patterns in wing feather δ13C and δ15N values indicated that 41% of the individuals from both subspecies shifted their diet or habitats during winter moult. Importantly, despite well-documented itinerancy in willow warblers during the winter, 59% of the individuals had feather isotope values consistent with stable use of habitats or diets during winter moult. Repeatability analyses suggest that individuals of both subspecies initiate moult in similar habitats from year-to-year while feeding on isotopically similar diets.

  • 24.
    Larson, Keith W.
    et al.
    Klamath Bird Observatory, PO Box 758, Ashland, OR 97520, USA.
    Martinez Leyva, Jesus Eduardo
    Wintering Black Terns Foraging Among Manta Rays in Coastal Guerrero, Mexico2007Ingår i: Waterbirds (De Leon Springs, Fla.), ISSN 1524-4695, E-ISSN 1938-5390, Vol. 30, nr 3, s. 448-449Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Winter observations of Black Terns (Chlidonias niger) in Mexico are rare. On 19 January 2007, we observed over 3,000 Black Terns foraging among hundreds of breaching manta rays one kilometer offshore on the coast of Guerrero, Mexico.

  • 25.
    Larson, Keith W.
    et al.
    Klamath Bird Observatory, Ashland, Oregon, USA; Department of Biology, Lund university, Lund, Sweden.
    Smith, Joseph A. M.
    Merker, Samuel A.
    Reitsma, Leonard R.
    Plasticity in the Swainson's Thrush (Catharus ustulatus) First Pre-basic Molt2013Ingår i: North American Bird Bander, Vol. 38, nr 1, s. 28-30Artikel i tidskrift (Refereegranskat)
  • 26. Lembrechts, Jonas J.
    et al.
    Aalto, Juha
    Ashcroft, Michael B.
    De Frenne, Pieter
    Kopecky, Martin
    Lenoir, Jonathan
    Luoto, Miska
    Maclean, Ilya M. D.
    Roupsard, Olivier
    Fuentes-Lillo, Eduardo
    Garcia, Rafael A.
    Pellissier, Loic
    Pitteloud, Camille
    Alatalo, Juha M.
    Smith, Stuart W.
    Bjork, Robert G.
    Muffler, Lena
    Backes, Amanda Ratier
    Cesarz, Simone
    Gottschall, Felix
    Okello, Joseph
    Urban, Josef
    Plichta, Roman
    Svatek, Martin
    Phartyal, Shyam S.
    Wipf, Sonja
    Eisenhauer, Nico
    Puscas, Mihai
    Turtureanu, Pavel D.
    Varlagin, Andrej
    Dimarco, Romina D.
    Jump, Alistair S.
    Randall, Krystal
    Dorrepaal, Ellen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Walz, Josefine
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Vitale, Luca
    Svoboda, Miroslav
    Higgens, Rebecca Finger
    Halbritter, H.
    Curasi, Salvatore R.
    Klupar, Ian
    Koontz, Austin
    Pearse, William D.
    Simpson, Elizabeth
    Stemkovski, Michael
    Graae, Bente Jessen
    Sorensen, Mia Vedel
    Hoye, Toke T.
    Fernandez Calzado, M. Rosa
    Lorite, Juan
    Carbognani, Michele
    Tomaselli, Marcello
    Forte, T'ai G. W.
    Petraglia, Alessandro
    Haesen, Stef
    Somers, Ben
    Van Meerbeek, Koenraad
    Bjorkman, Mats P.
    Hylander, Kristoffer
    Merinero, Sonia
    Gharun, Mana
    Buchmann, Nina
    Dolezal, Jiri
    Matula, Radim
    Thomas, Andrew D.
    Bailey, Joseph J.
    Ghosn, Dany
    Kazakis, George
    de Pablo, Miguel A.
    Kemppinen, Julia
    Niittynen, Pekka
    Rew, Lisa
    Seipel, Tim
    Larson, Christian
    Speed, James D. M.
    Ardo, Jonas
    Cannone, Nicoletta
    Guglielmin, Mauro
    Malfasi, Francesco
    Bader, Maaike Y.
    Canessa, Rafaella
    Stanisci, Angela
    Kreyling, Juergen
    Schmeddes, Jonas
    Teuber, Laurenz
    Aschero, Valeria
    Ciliak, Marek
    Malis, Frantisek
    De Smedt, Pallieter
    Govaert, Sanne
    Meeussen, Camille
    Vangansbeke, Pieter
    Gigauri, Khatuna
    Lamprecht, Andrea
    Pauli, Harald
    Steinbauer, Klaus
    Winkler, Manuela
    Ueyama, Masahito
    Nunez, Martin A.
    Ursu, Tudor-Mihai
    Haider, Sylvia
    Wedegartner, Ronja E. M.
    Smiljanic, Marko
    Trouillier, Mario
    Wilmking, Martin
    Altman, Jan
    Bruna, Josef
    Hederova, Lucia
    Macek, Martin
    Man, Matej
    Wild, Jan
    Vittoz, Pascal
    Partel, Meelis
    Barancok, Peter
    Kanka, Robert
    Kollar, Jozef
    Palaj, Andrej
    Barros, Agustina
    Mazzolari, Ana C.
    Bauters, Marijn
    Boeckx, Pascal
    Benito Alonso, Jose-Luis
    Zong, Shengwei
    Di Cecco, Valter
    Sitkova, Zuzana
    Tielboerger, Katja
    van den Brink, Liesbeth
    Weigel, Robert
    Homeier, Juergen
    Dahlberg, C. Johan
    Medinets, Sergiy
    Medinets, Volodymyr
    De Boeck, Hans J.
    Portillo-Estrada, Miguel
    Verryckt, Lore T.
    Milbau, Ann
    Daskalova, Gergana N.
    Thomas, Haydn J. D.
    Myers-Smith, Isla H.
    Blonder, Benjamin
    Stephan, Jorg G.
    Descombes, Patrice
    Zellweger, Florian
    Frei, Esther R.
    Heinesch, Bernard
    Andrews, Christopher
    Dick, Jan
    Siebicke, Lukas
    Rocha, Adrian
    Senior, Rebecca A.
    Rixen, Christian
    Jimenez, Juan J.
    Boike, Julia
    Pauchard, Anibal
    Scholten, Thomas
    Scheffers, Brett
    Klinges, David
    Basham, Edmund W.
    Zhang, Jian
    Zhang, Zhaochen
    Geron, Charly
    Fazlioglu, Fatih
    Candan, Onur
    Sallo Bravo, Jhonatan
    Hrbacek, Filip
    Laska, Kamil
    Cremonese, Edoardo
    Haase, Peter
    Moyano, Fernando E.
    Rossi, Christian
    Nijs, Ivan
    SoilTemp: A global database of near-surface temperature2020Ingår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 26, nr 11, s. 6616-6629Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long‐term average thermal conditions at coarse spatial resolutions only. Hence, many climate‐forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particularly important in relation to effects of observation height (e.g. vegetation, snow and soil characteristics) and in habitats varying in their exposure to radiation, moisture and wind (e.g. topography, radiative forcing or cold‐air pooling). Since organisms living close to the ground relate more strongly to these microclimatic conditions than to free‐air temperatures, microclimatic ground and near‐surface data are needed to provide realistic forecasts of the fate of such organisms under anthropogenic climate change, as well as of the functioning of the ecosystems they live in. To fill this critical gap, we highlight a call for temperature time series submissions to SoilTemp, a geospatial database initiative compiling soil and near‐surface temperature data from all over the world. Currently, this database contains time series from 7,538 temperature sensors from 51 countries across all key biomes. The database will pave the way toward an improved global understanding of microclimate and bridge the gap between the available climate data and the climate at fine spatiotemporal resolutions relevant to most organisms and ecosystem processes.

  • 27.
    Lembrechts, Jonas J.
    et al.
    Research Group PLECO (Plants and Ecosystems), University of Antwerp, Wilrijk, Belgium.
    van den Hoogen, Johan
    Department of Environmental Systems Science, Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland.
    Dorrepaal, Ellen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sarneel, Judith M.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Walz, Josefine
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Nijs, Ivan
    Research Group PLECO (Plants and Ecosystems), University of Antwerp, Wilrijk, Belgium.
    Lenoir, Jonathan
    UMR 7058 CNRS ‘Ecologie et Dynamique des Systèmes Anthropisés’ (EDYSAN), Univ. de Picardie Jules Verne, Amiens, France.
    Global maps of soil temperature2022Ingår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 28, nr 9, s. 3110-3144Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

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  • 28. Liedvogel, Miriam
    et al.
    Larson, Keith W.
    Center for Animal Movement Research (CAnMove), Department of Biology, Lund University, 22362 Lund, Sweden.
    Lundberg, Max
    Gursoy, Arzu
    Wassenaar, Leonard I.
    Hobson, Keith A.
    Bensch, Staffan
    Åkesson, Susanne
    No evidence for assortative mating within a willow warbler migratory divide2014Ingår i: Frontiers in Zoology, E-ISSN 1742-9994, Vol. 11, artikel-id 52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In contact zones, genetic mixing of two taxa can be restricted by prezygotic (e.g. assortative mating) or postzygotic (lower fitness of hybrid offspring) barriers, or a combination of the two. A hybrid zone between two willow warbler subspecies (Phylloscopus trochilus trochilus, P. t. acredula) with distinctive migratory strategies occurs in central Sweden. These subspecies exhibit differences in migratory direction and distance, resulting in geographically distinct wintering areas in Africa. The subspecies may have diverged from a common refuge after the last ice age, and neutral genetic markers are homogeneous across their range. By contrast, several phenotypic traits and genetic markers of two chromosomal regions previously identified show steep clines across the divide. The evolutionary forces that maintain this migratory divide remain unknown. Here we use plumage colour, morphology, genetic markers and feather stable nitrogen-isotopes (δ 15N) to assess if assortative mating between migratory phenotypes could be acting as a possible mechanism for keeping the two forms genetically separate and maintaining the migratory divide. We colour-ringed a willow warbler breeding population in the central part of the hybrid zone and observed the breeding population to assess phenotypic and genotypic traits of social pairs.

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  • 29.
    Lindborg, Regina
    et al.
    Landscape, Environment and Geomatics, Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    Ermold, Matti
    Landscape, Environment and Geomatics, Department of Physical Geography, Stockholm University, Stockholm, Sweden.
    Kuglerová, Lenka
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Jansson, Roland
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Larson, Keith W.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Milbau, Ann
    Province of Antwerp, Department of Sustainable Environment and Nature Policy, Antwerp, Belgium.
    Cousins, Sara A. O.
    Landscape, Environment and Geomatics, Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
    How does a wetland plant respond to increasing temperature along a latitudinal gradient?2021Ingår i: Ecology and Evolution, E-ISSN 2045-7758, Vol. 11, nr 22, s. 16228-16238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Global warming affects plant fitness through changes in functional traits and thereby ecosystem function. Wetlands are declining worldwide, and hence, ecosystem functions linked to wetlands are threatened. We use Caltha palustris “a common wetland plant” to study whether warming affects growth and reproduction differently depending on origin of source population, potentially affecting phenotypic response to local climate. We conducted a 2-year in situ temperature manipulation experiment using clone pairs of C. palustris in four regions, along a 1300-km latitudinal gradient of Sweden. Open-top chambers were used to passively increase temperature, paired with controls. Growth and reproductive traits were measured from 320 plants (four regions × five sites × two treatments × eight plants) over two consecutive seasons to assess the effect of warming over time. We found that warming increased plant height, leaf area, number of leaves, and roots. High-latitude populations responded more strongly to warming than low-latitude populations, especially by increasing leaf area. Warming increased number of flowers in general, but only in the second year, while number of fruits increased in low-latitude populations the first year. Prolonged warming leads to an increase in both number of leaves and flowers over time. While reproduction shows varying and regional responses to warming, impacts on plant growth, especially in high-latitude populations, have more profound effects. Such effects could lead to changes in plant community composition with increased abundance of fast-growing plants with larger leaves and more clones, affecting plant competition and ecological functions such as decomposition and nutrient retention. Effects of warming were highly context dependent; thus, we encourage further use of warming experiments to predict changes in growth, reproduction, and community composition across wetland types and climate gradients targeting different plant forms.

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  • 30. Lundberg, Max
    et al.
    Boss, John
    Canbäck, Björn
    Liedvogel, Miriam
    Larson, Keith W.
    Grahn, Mats
    Åkesson, Susanne
    Bensch, Staffan
    Wright, Anthony
    Characterisation of a transcriptome to find sequence differences between two differentially migrating subspecies of the willow warbler Phylloscopus trochilus2013Ingår i: BMC Genomics, E-ISSN 1471-2164, Vol. 14, nr 1, s. 1-11, artikel-id 330Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Animal migration requires adaptations in morphological, physiological and behavioural traits. Several of these traits have been shown to possess a strong heritable component in birds, but little is known about their genetic architecture. Here we used 454 sequencing of brain-derived transcriptomes from two differentially migrating subspecies of the willow warbler Phylloscopus trochilus to detect genes potentially underlying traits associated with migration. Results: The transcriptome sequencing resulted in 1.8 million reads following filtering steps. Most of the reads (84%) were successfully mapped to the genome of the zebra finch Taeniopygia gutatta. The mapped reads were situated within at least 12,101 predicted zebra finch genes, with the greatest sequencing depth in exons. Reads that were mapped to intergenic regions were generally located close to predicted genes and possibly located in uncharacterized untranslated regions (UTRs). Out of 85,000 single nucleotide polymorphisms (SNPs) with a minimum sequencing depth of eight reads from each of two subspecies-specific pools, only 55 showed high differentiation, confirming previous studies showing that most of the genetic variation is shared between the subspecies. Validation of a subset of the most highly differentiated SNPs using Sanger sequencing demonstrated that several of them also were differentiated between an independent set of individuals of each subspecies. These SNPs were clustered in two chromosome regions that are likely to be influenced by divergent selection between the subspecies and that could potentially be associated with adaptations to their different migratory strategies. Conclusions: Our study represents the first large-scale sequencing analysis aiming at detecting genes underlying migratory phenotypes in birds and provides new candidates for genes potentially involved in migration.

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  • 31. Lundberg, Max
    et al.
    Liedvogel, Miriam
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sigeman, Hanna
    Grahn, Mats
    Wright, Anthony
    Akesson, Susanne
    Bensch, Steffan
    Genetic differences between willow warbler migratory phenotypes are few and cluster in large haplotype blocks2017Ingår i: Evolution Letters, E-ISSN 2056-3744, Vol. 1, nr 3, s. 155-168Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is well established that differences in migratory behavior between populations of songbirds have a genetic basis but the actual genes underlying these traits remains largely unknown. In an attempt to identify such candidate genes we de novo assembled the genome of the willow warbler Phylloscopus trochilus, and used whole-genome resequencing and a SNP array to associate genomic variation with migratory phenotypes across two migratory divides around the Baltic Sea that separate SW migrating P. t. trochilus wintering in western Africa and SSE migrating P. t. acredula wintering in eastern and southern Africa. We found that the genomes of the two migratory phenotypes lack clear differences except for three highly differentiated regions located on chromosomes 1, 3, and 5 (containing 146, 135, and 53 genes, respectively). Within each migratory phenotype we found virtually no differences in allele frequencies for thousands of SNPs, even when comparing geographically distant populations breeding in Scandinavia and Far East Russia (>6000 km). In each of the three differentiated regions, multidimensional scaling-based clustering of SNP genotypes from more than 1100 individuals demonstrates the presence of distinct haplotype clusters that are associated with each migratory phenotype. In turn, this suggests that recombination is absent or rare between haplotypes, which could be explained by inversion polymorphisms. Whereas SNP alleles on chromosome 3 correlate with breeding altitude and latitude, the allele distribution within the regions on chromosomes 1 and 5 perfectly matches the geographical distribution of the migratory phenotypes. The most differentiated 10 kb windows and missense mutations within these differentiated regions are associated with genes involved in fatty acid synthesis, possibly representing physiological adaptations to the different migratory strategies. The similar to 200 genes in these regions, of which several lack described function, will direct future experimental and comparative studies in the search for genes that underlie important migratory traits.

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  • 32.
    MacDougall, Andrew S.
    et al.
    Umeå universitet. Department of Integrative Biology, University of Guelph, Guelph, ON, Canada.
    Caplat, Paul
    Olofsson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Siewert, Matthias B.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Bonner, Colin
    Esch, Ellen
    Lessard-Therrien, Malie
    Rosenzweig, Hannah
    Umeå universitet.
    Schäfer, Anne-Kathrin
    Umeå universitet.
    Raker, Pia
    Umeå universitet.
    Ridha, Hassan
    Umeå universitet.
    Bolmgren, Kjell
    Umeå universitet.
    Fries, Thore C. E.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Comparison of the distribution and phenology of Arctic Mountain plants between the early 20th and 21st centuries2021Ingår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 27, nr 20, s. 5070-5083Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Arctic plants are adapted to climatic variability, but their long-term responses to warming remain unclear. Responses may occur by range shifts, phenological adjustments in growth and reproduction, or both. Here, we compare distribution and phenology of 83 arctic and boreal mountain species, sampled identically in the early 20th (1917-1919) and 21st centuries (2017-2018) from a region of northern Sweden that has warmed significantly. We test two compensatory hypotheses to high-latitude warming-upward shifts in distribution, and earlier or extended growth and reproduction. For distribution, we show dramatic upward migration by 69% of species, averaging 6.1 m per decade, especially boreal woodland taxa whose upward expansion has reduced arctic montane habitat by 30%. Twenty percent of summit species showed distributional shifts but downward, especially moisture-associated snowbed flora. For phenology, we detected wide inter-annual variability in the onset of leafing and flowering in both eras. However, there was no detectable change in growing-season length, relating to two mechanisms. First, plot-level snow melt data starting in 1917 demonstrated that melt date, rather than vernal temperatures, better predicts plant emergence, with snow melt influenced by warmer years having greater snowfall-warmer springs did not always result in earlier emergence because snowbeds can persist longer. Second, the onset of reproductive senescence between eras was similar, even when plant emergence was earlier by a month, possibly due to intensified summer heat stress or hard-wired 'canalization' where senescence occurs regardless of summer temperature. Migrations in this system have possibly buffered arctic species against displacement by boreal expansion and warming, but ongoing temperature increases, woody plant invasion, and a potential lack of flexibility in timing of senescence may foreshadow challenges.

  • 33.
    Milarska, Sylwia E.
    et al.
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Androsiuk, Piotr
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Paukszto, Łukasz
    Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Pl. Łódzki 1, Olsztyn, Poland.
    Jastrzębski, Jan P.
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Maździarz, Mateusz
    Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Pl. Łódzki 1, Olsztyn, Poland.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Giełwanowska, Irena
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Complete chloroplast genomes of Cerastium alpinum, C. arcticum and C. nigrescens: genome structures, comparative and phylogenetic analysis2023Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 13, nr 1, artikel-id 18774Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The genus Cerastium includes about 200 species that are mostly found in the temperate climates of the Northern Hemisphere. Here we report the complete chloroplast genomes of Cerastium alpinum, C. arcticum and C. nigrescens. The length of cp genomes ranged from 147,940 to 148,722 bp. Their quadripartite circular structure had the same gene organization and content, containing 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. Repeat sequences varied from 16 to 23 per species, with palindromic repeats being the most frequent. The number of identified SSRs ranged from 20 to 23 per species and they were mainly composed of mononucleotide repeats containing A/T units. Based on Ka/Ks ratio values, most genes were subjected to purifying selection. The newly sequenced chloroplast genomes were characterized by a high frequency of RNA editing, including both C to U and U to C conversion. The phylogenetic relationships within the genus Cerastium and family Caryophyllaceae were reconstructed based on the sequences of 71 protein-coding genes. The topology of the phylogenetic tree was consistent with the systematic position of the studied species. All representatives of the genus Cerastium were gathered in a single clade with C. glomeratum sharing the least similarity with the others.

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  • 34.
    Milarska, Sylwia Eryka
    et al.
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Androsiuk, Piotr
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Bednarek, Piotr Tomasz
    Plant Breeding and Acclimatization Institute – National Research Institute, Radzików, Błonie, Poland.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Giełwanowska, Irena
    Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 1A, Olsztyn, Poland.
    Genetic variation of Cerastium alpinum L. from Babia Góra, a critically endangered species in Poland2023Ingår i: Journal of Applied Genetics, ISSN 1234-1983, E-ISSN 2190-3883, Vol. 64, s. 37-53Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Babia Góra massif is the only site of occurrence of the Cerastium alpinum L. in Poland, an arctic-alpine perennial plant with a wide distribution in North America, northwestern Asia, and Europe. To determine whether the isolated Polish populations are genetically distinct, we have performed an evaluation of C. alpinum from Babia Góra with the use of iPBS markers. A total number of 133 individuals of C. alpinum from seven populations representing four localizations of the species were analyzed, i.e., from Babia Góra (Poland), Alps (Switzerland), Nuolja massif (Sweden), and Kaffiøyra (Svalbard, Norway). Genetic analysis of all C. alpinum samples using eight PBS primers identified 262 bands, 79.4% of which were polymorphic. iPBS markers revealed low genetic diversity (average He = 0.085) and high population differentiation (FST = 0.617). AMOVA results confirmed that the majority of the genetic variation (62%) was recorded among populations. The grouping revealed by PCoA showed that C. alpinum from Svalbard is the most diverged population, C. alpinum from Switzerland and Sweden form a pair of similar populations, whereas C. alpinum from the Babia Góra form a heterogeneous group of four populations. Results of isolation by distance analysis suggested that the spatial distance is the most probable cause of the observed differentiation among populations. Although significant traces of a bottleneck effect were noted for all populations of C. alpinum from Babia Góra, the populations still maintain a low but significant level of genetic polymorphism. These results are of great importance for developing conservation strategies for this species in Poland.

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  • 35. Molina, Kathy C.
    et al.
    Garrett, Kimball L.
    Larson, Keith W.
    Klamath Bird Observatory, P. O. Box 758, Ashland. Oregon 97520; Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
    Craig, David P.
    The Winter Distribution of the Western Gull-billed Tern (Gelochelidon nilotica vanrossemi)2009Ingår i: Western Birds, ISSN 0160-1121, Vol. 40, nr 1, s. 2-20Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    We surveyed 73 sites along the Gulf of California and Pacific coasts of mainland Mexico during five nonbreeding seasons from December 1999 to January 2007 to clarify the winter status and distribution of the western North American subspecies of the Gull-billed Tern (Gelochelidon nilotica vanrossemi), a taxon of conservation concern. We located birds at 44 of the 73 sites, (60%) with the largest numbers found around coastal lagoons with extensive tidal flats in southern Sonora, Sinaloa, and extreme northern Nayarit. Local concentrations were also noted at other sites from the Colorado River delta of extreme northwestern Sonora south to Guerrero. Resightings of birds banded as chicks at California breeding colonies establish the first evidence of connectivity to specific wintering sites in Mexico as far south as southern Sonora and possibly into Nayarit.

  • 36. Schiller, Anja M.
    et al.
    Larson, Keith W.
    Fox Sparrow foraging on a king bolete mushroom2006Ingår i: Northwest Naturalist: a journal of vertebrate biology, ISSN 1051-1733, Vol. 87, nr 3, s. 252-252Artikel i tidskrift (Refereegranskat)
  • 37. Schiller, Anja M.
    et al.
    Larson, Keith W.
    Klamath Bird Observatory, Ashland, Oregon.
    Alexander, John D.
    A White-crowned Sparrow with three legs2007Ingår i: Western Birds, ISSN 0160-1121, Vol. 38, nr 3, s. 222-223Artikel i tidskrift (Refereegranskat)
  • 38.
    Sharf, William C.
    et al.
    Lake Superior State University.
    Benson, Anna-Marie
    Larson, Keith
    Two same-season, long-distance recaptures of alder flycatchers in Alaska2019Ingår i: North American Bird Bander, ISSN 0363-8979, Vol. 44, nr 2-3, s. 168-170, artikel-id 4Artikel i tidskrift (Refereegranskat)
  • 39.
    Simba, Lavhelesani D.
    et al.
    Centre for African Conservation Ecology, Nelson Mandela University, Gqeberha, South Africa.
    te Beest, Mariska
    Centre for African Conservation Ecology, Nelson Mandela University, Gqeberha, South Africa; Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands; South African Environmental Observation Network (SAEON), Grasslands, Forests and Wetlands Node, Pietermaritzburg, South Africa.
    Hawkins, Heidi-Jayne
    Conservation International, Forrest House, Belmont Park, Rondebosch, Cape Town, South Africa; Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa.
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Palmer, Anthony R.
    Institute for Water Research, Rhodes University, Makhanda, South Africa.
    Sandström, Camilla
    Umeå universitet, Samhällsvetenskapliga fakulteten, Statsvetenskapliga institutionen.
    Smart, Kathleen G.
    Institute for Water Research, Rhodes University, Makhanda, South Africa; Expanded Freshwater and Terrestrial Environmental Observation Network (EFTEON), Pietermaritzburg, South Africa.
    Kerley, Graham I. H.
    Centre for African Conservation Ecology, Nelson Mandela University, Gqeberha, South Africa.
    Cromsigt, Joris P. G. M.
    Centre for African Conservation Ecology, Nelson Mandela University, Gqeberha, South Africa; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Wilder rangelands as a natural climate opportunity: linking climate action to biodiversity conservation and social transformation2024Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rangelands face threats from climate and land-use change, including inappropriate climate change mitigation initiatives such as tree planting in grassy ecosystems. The marginalization and impoverishment of rangeland communities and their indigenous knowledge systems, and the loss of biodiversity and ecosystem services, are additional major challenges. To address these issues, we propose the wilder rangelands integrated framework, co-developed by South African and European scientists from diverse disciplines, as an opportunity to address the climate, livelihood, and biodiversity challenges in the world’s rangelands. More specifically, we present a Theory of Change to guide the design, monitoring, and evaluation of wilder rangelands. Through this, we aim to promote rangeland restoration, where local communities collaborate with regional and international actors to co-create new rangeland use models that simultaneously mitigate the impacts of climate change, restore biodiversity, and improve both ecosystem functioning and livelihoods.

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  • 40. Wassenaar, Leonard I.
    et al.
    Van Wilgenburg, Steve L.
    Larson, Keith W.
    Klamath Bird Observatory, PO Box 758, Ashland, OR, 97520, USA; Department of Animal Ecology, University of Lund, Lund, Sweden.
    Hobson, Keith A.
    A groundwater isoscape (δD, δ18O) for Mexico2009Ingår i: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 102, nr 3, s. 123-136Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Numerous studies have shown that precipitation isocapes drive δD and δ18O patterns in surficial waters and in terrestrial food webs. While the GNIP (Global Network for Isotopes in Precipitation) dataset provided a key foundation for linking precipitation-terrestrial isoscapes globally, it has insufficient spatial coverage in many countries like Mexico. To overcome this limitation, we hypothesized that shallow phreatic groundwaters in Mexico could be used as an isotopic integrator of long-term seasonally weighted precipitation inputs to the landscape to aid in calibrating spatial H and O isotope datasets for terrestrial, biological and hydrological research. Groundwater was sampled from 234 sites in Mexico at ~ 50 km latitudinal spacing to obtain high spatial resolution and country-wide coverage for the construction of a groundwater isoscape. Our data revealed that shallow groundwater infiltration in Mexico appears largely unaffected by evaporation and reflects seasonally weighted precipitation inputs. These precipitation inputs are primarily biased to summertime when highest rainfall occurs, but a small degree of post-precipitation evaporation revealed a lower d-excess zone that corresponded to the interior semi-arid ecozone. We developed a predictive general linear model (GLM) for hydrogen and oxygen isotopic spatial patterns in Mexican groundwater and then compared the results to a validation subset of our field data, as well external data reported in the literature. The GLM used elevation, latitude, drainage basin (Atlantic vs. Pacific), and rainfall as the most relevant predictive variables. The GLM explained 81% of the overall isotopic variance observed in groundwater, 68% of the variance within our validation subset, and 77% of the variance in the external data set. Our predictive GLM is sufficiently accurate to allow for future ecological, hydrological and forensic isoscape applications in Mexico, and may be an approach that is applicable to other countries and regions where GNIP stations are lacking.

  • 41. Wellenreuther, M.
    et al.
    Rosenquist, H.
    Jaksons, P.
    Larson, Keith W
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Local adaptation along an environmental cline in a species with an inversion polymorphism2017Ingår i: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 30, nr 6, s. 1068-1077Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Polymorphic inversions are ubiquitous across the animal kingdom and are frequently associated with clines in inversion frequencies across environmental gradients. Such clines are thought to result from selection favouring local adaptation; however, empirical tests are scarce. The seaweed fly Coelopa frigida has an alpha/beta inversion polymorphism, and previous work demonstrated that the alpha inversion frequency declines from the North Sea to the Baltic Sea and is correlated with changes in tidal range, salinity, algal composition and wrackbed stability. Here, we explicitly test the hypothesis that populations of C. frigida along this cline are locally adapted by conducting a reciprocal transplant experiment of four populations along this cline to quantify survival. We found that survival varied significantly across treatments and detected a significant Location x Substrate interaction, indicating local adaptation. Survival models showed that flies from locations at both extremes had highest survival on their native substrates, demonstrating that local adaptation is present at the extremes of the cline. Survival at the two intermediate locations was, however, not elevated at the native substrates, suggesting that gene flow in intermediate habitats may override selection. Together, our results support the notion that population extremes of species with polymorphic inversions are often locally adapted, even when spatially close, consistent with the growing view that inversions can have direct and strong effects on the fitness of species.

  • 42. Wellenreuther, Maren
    et al.
    Larson, Keith W.
    Evolutionary Ecology Unit, Department of Biology, Ecology Building, Lund University, SE-223 62 Lund, Sweden.
    Svensson, Erik I.
    Climatic niche divergence or conservatism?: Environmental niches and range limits in ecologically similar damselflies2012Ingår i: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 93, nr 6, s. 1353-1366Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The factors that determine species' range limits are of central interest to biologists. One particularly interesting group comprises odonates (dragonflies and damselflies), which show large differences in secondary sexual traits and respond quickly to climatic factors, but often have minor interspecific niche differences, challenging models of niche-based species coexistence. We quantified the environmental niches at two geographic scales to understand the ecological causes of northern range limits and the coexistence of two congeneric damselflies (Calopteryx splendens and C. virgo). Using environmental niche modeling, we quantified niche divergence first across the whole geographic range in Fennoscandia, and second only in the sympatric part of this range. We found evidence for interspecific divergence along the environmental axes of temperature and precipitation across the northern range in Fennoscandia, suggesting that adaptation to colder and wetter climate might have allowed C. virgo to expand farther north than C. splendens. However, in the sympatric zone in southern Fennoscandia we found only negligible and nonsignificant niche differences. Minor niche differences in sympatry lead to frequent encounters and intense interspecific sexual interactions at the local scale of populations. Nevertheless, niche differences across Fennoscandia suggest that species differences in physiological tolerances limit range expansions northward, and that current and future climate could have large effects on the distributional ranges of these and ecologically similar insects.

  • 43. Zhao, Tianhao
    et al.
    Ilieva, Mihaela
    Larson, Keith
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lundberg, Max
    Neto, Jùlio M.
    Sokolovskis, Kristaps
    Akesson, Susanne
    Bensch, Staffan
    Autumn migration direction of juvenile willow warblers (Phylloscopus t. trochilus and P. t. acredula) and their hybrids assessed by qPCR SNP genotyping2020Ingår i: Movement Ecology, E-ISSN 2051-3933, Vol. 8, nr 1, artikel-id 22Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Backgrounds Geographic regions, where two closely related taxa with different migration routes come into contact, are known as migratory divides. Hybrids originating from migratory divides are hypothesized to migrate intermediately relative to the parental populations. Few studies have tested this hypothesis in wild birds, and only in hybrids that have completed the migration back to the breeding grounds. Here, we make use of the well-established migration routes of willow warblers (Phylloscopus trochilus), for which the subspecies trochilus and acredula have migration-associated genetic markers on chromosomes 1 and 5. The genetic approach enabled us to analyze the geographic distribution of juveniles during their first autumn migration, predicting that hybrids should be more frequent in the central flyway over Italy than along the typical SW routes of trochilus and SE routes of acredula. Methods Blood and feather samples were collected from wintering birds in Africa (n = 69), and from juveniles during autumn migration in Portugal (n = 33), Italy (n = 38) and Bulgaria (n = 32). Genotyping was carried out by qPCR SNP assays, on one SNP each on chromosome 1 (SNP 65) and chromosome 5 (SNP 285). Both these SNPs have alternative alleles that are highly fixed (> 97%) in each of the subspecies. Results The observed combined genotypes of the two SNPs were associated with the known migration routes and wintering distributions of trochilus and acredula, respectively. We found hybrids (HH) among the juveniles in Italy (5/38) and in Portugal (2/33). The proportion of hybrids in Italy was significantly higher than expected from a background rate of hybrid genotypes (1.5%) in allopatric populations of the subspecies. Conclusions Our genetic approach to assign individuals to subspecies and hybrids allowed us to investigate migration direction in juvenile birds on their first migration, which should better reflect the innate migratory direction than studies restricted to successful migrants. The excess of hybrids in Italy, suggests that they employ an intermediate route relative to the parental populations. Our qPCR SNP genotyping method is efficient for processing large sample sizes, and will therefore be useful in migration research of species with known population genetic structure.

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