Are gastrointestinal parasites associated with the cyclic population dynamics of their arctic lemming hosts?

• Published in: International Journal for Parasitology: Parasites and Wildlife
• Main Authors: Gilg, Olivier, Bollache, Loïc, Afonso, Eve, Yannic, Glenn, Schmidt, Niels Martin, Hansen, Lars Holst, Hansen, Jannik, Sittler, Benoît, Lang, Johannes, Meyer, Nicolas, Sabard, Brigitte, Gilg, Vladimir, Lang, Anita, Lebbar, Mathilde, Haukisalmi, Voitto, Henttonen, Heikki, Moreau, Jérôme
• Other Authors: Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté COMUE (UBFC)-Université Bourgogne Franche-Comté COMUE (UBFC), Groupe de recherche en écologie arctique (GREA), Groupe de Recherche en Ecologie Arctique, Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Department of Bioscience, Aarhus University Aarhus -Arctic Research Centre, Chair for Nature Conservation and Landscape Ecology, Clinic for Birds, Reptiles, Amphibians & Fish, Justus-Liebig-Universität Gießen = Justus Liebig University (JLU), Natural Resources Institute Finland (LUKE), Biogéosciences UMR 6282 (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Study supported by the French Polar Institute-IPEV Program “Interactions 1036” and analyses funded by the Fondation de Coopération Scientifique of the Université de Bourgogne Franche-Comté grant “BQR” .
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Cestodes; Eimerians; Faecal prevalence; Greenland; Population dynamics; Rodent-parasites interactions; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDV.EE.IEO]Life Sciences [q-bio]/Ecology; environment/Symbiosis; [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology; Arctic Lemming; Arctic
• Online Access: https://hal.science/hal-02281730; https://hal.science/hal-02281730/document; https://hal.science/hal-02281730/file/S2213224419300744.pdf; https://doi.org/10.1016/j.ijppaw.2019.06.011

7 pages International audience Many rodents, including most populations of arctic lemmings (genus Dicrostonyx and Lemmus), have cyclic population dynamics. Among the numerous hypotheses which have been proposed and tested to explain this typical characteristic of some terrestrial vertebrate communities, trophic interactions have often been presented as the most likely drivers of these periodic fluctuations. The possible role of parasites has, however, only seldom been assessed. In this study, we genetically measured the prevalence of two endoparasite taxa, eimerians and cestodes, in 372 faecal samples from collared lemmings, over a five year period and across three distant sites in Northeast Greenland. Prevalence of cestodes was low (2.7% over all sites and years) and this taxon was only found at one site (although in 4 out of 5 years) in adult hosts. By contrast, we found high prevalence for eimerians (77.7% over all sites and years), which occurred at all sites, in every year, for both age classes (at the Hochstetter Forland site where both adult and juvenile faeces were collected) and regardless of reproductive and social status inferred from the characteristics of the lemming nests where the samples had been collected. Prevalence of eimerians significantly varied among years (not among sites) and was higher for juvenile than for adult lemmings at the Hochstetter Forland site. However, higher prevalence of eimerians (P t ) was only associated with lower lemming density (N t ) at one of the three sites and we found no delayed density dependence between N t and P t+1 to support the parasite hypothesis. Our results show that there is no clear relation between lemming density and eimerian faecal prevalence in Northeast Greenland and hence no evidence that eimerians could be driving the cyclic population dynamics of collared lemmings in this region.