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showing 10 items of 9311 documents
Brown trout (Salmo trutta L.) high genetic diversity around the Tyrrhenian Sea as revealed by nuclear and mitochondrial markers
2018
The brown trout (Salmo trutta L.) is widely distributed all around Europe but its natural diversity is threatened by massive stocking with Atlantic domestic strains. Describing the remaining natural genetic diversity and the proportion of domestic hatchery strains in rivers is a prerequisite for smart conservation. The high genetic diversity of brown trout populations around the Tyrrhenian Sea is well known. Use of twelve microsatellites has allowed description of the natural genetic structure of populations and detection of the consequences of stocking. Mitochondrial DNA control region sequences and the LDH-C1* gene enabled placement of each population into one of the six mitochondrial and…
Windthrow in streamside key habitats: Effects of buffer strip width and selective logging
2020
Abstract Streamside forests are preserved from clear-cut logging in production forests and protected with uncut buffer strips in many countries. However, buffer strips often remain narrow due to economic reasons and, therefore, provide weak protection against adverse edge effects of clear-cuts and are vulnerable to windthrow. Selective logging of buffer strips is sometimes allowed to reduce their costs, but the decreased tree density may expose the buffer to higher occurrence of windthrow. We used a replicated two-factor experiment to assess the effects of buffer width (15 m or 30 m) and selective logging (0% or 30% of the basal area removed) on the risk of windthrow in boreal streamside fo…
Corsican Pine (Pinus laricio Poiret) Stand Management: Medium and Long Lasting Effects of Thinning on Biomass Growth
2018
Originally published in Forests: Picchio R, Venanzi R, Latterini F, Marchi E, Laschi A, Lo Monaco A (2018). Corsican pine (Pinus laricio Poiret) stand management: medium and long lasting effects of thinning on biomass growth. Forests 9 (5), article number 257, p. 1-17 (open access) DOI: 10.3390/f9050257 This article can be downloaded at: https://www.mdpi.com/1999-4907/9/5/257 Abstract With the aim of acquiring better comprehension of the ecological and productive aspects of the management of pine forests, we monitored logging damage and evaluated the effects of thinning on stand growth 20 years after the treatment in a Pinus laricio Poiret stand in central Italy. The objectives of the p…
Diversifying selection on MHC class I in the house sparrow (Passer domesticus).
2009
10 pages; International audience; Genes of the major histocompatibility complex (MHC) are the most polymorphic loci known in vertebrates. Two main hypotheses have been put forward to explain the maintenance of MHC diversity: pathogen-mediated selection and MHC-based mate choice. Host-parasite interactions can maintain MHC diversity via frequency-dependent selection, heterozygote advantage, and diversifying selection (spatially and/or temporally heterogeneous selection). In this study, we wished to investigate the nature of selection acting on the MHC class I across spatially structured populations of house sparrows (Passer domesticus) in France. To infer the nature of the selection, we comp…
Diet Quality Limits Summer Growth of Field Vole Populations
2014
Marked variation occurs in both seasonal and multiannual population density peaks of northern European small mammal species, including voles. The availability of dietary proteins is a key factor limiting the population growth of herbivore species. The objective of this study is to investigate the degree to which protein availability influences the growth of increasing vole populations. We hypothesise that the summer growth of folivorous vole populations is positively associated with dietary protein availability. A field experiment was conducted over a summer reproductive period in 18 vegetated enclosures. Populations of field voles (Microtus agrestis) were randomised amongst three treatment…
Hantavirus infections in fluctuating host populations: the role of maternal antibodies.
2010
Infected females may transfer maternal antibodies (MatAbs) to their offspring, which may then be transiently protected against infections the mother has encountered. However, the role of maternal protection in infectious disease dynamics in wildlife has largely been neglected. Here, we investigate the effects of Puumala hantavirus (PUUV)-specific MatAbs on PUUV dynamics, using 7 years' data from a cyclic bank vole population in Finland. For the first time to our knowledge, we partition seropositivity data from a natural population into separate dynamic patterns for MatAbs and infection. The likelihood of young of the year carrying PUUV-specific MatAbs during the breeding season correlated p…
EPIDEMIOLOGY OF PLASMODIUM RELICTUM INFECTION IN THE HOUSE SPARROW.
2014
International audience; : Abstract In vertebrates, multiple host characteristics and environmental factors are known to influence infectious disease dynamics. Here, we investigated variability in prevalence and parasitemia of Plasmodium relictum in the house sparrow (Passer domesticus), across a large number of rural and urban populations (n = 16). We found that prevalence was not predicted by any of the host traits investigated (age, sex, body mass or wing length). However, parasitemia was significantly higher in females when compared to males and in 1-yr-olds as compared to older individuals. Neither prevalence nor parasitemia differed according to habitat type (urban vs. rural). These re…
Urbanization, trace metal pollution, and malaria prevalence in the house sparrow.
2013
10 pages; International audience; Anthropogenic pollution poses a threat for the environment and wildlife. Trace metals (TMs) are known to have negative effects on haematological status, oxidative balance, and reproductive success in birds. These pollutants particularly increase in concentration in industrialized, urbanized and intensive agricultural areas. Pollutants can also interfere with the normal functioning of the immune system and, as such, alter the dynamics of host-parasite interactions. Nevertheless, the impact of pollution on infectious diseases has been largely neglected in natural populations of vertebrates. Here, we used a large spatial scale monitoring of 16 house sparrow (P…
Phenotypic Divergence among West European Populations of Reed Bunting Emberiza schoeniclus: The Effects of Migratory and Foraging Behaviours
2013
[EN] Divergent selection and local adaptation are responsible for many phenotypic differences between populations, potentially leading to speciation through the evolution of reproductive barriers. Here we evaluated the morphometric divergence among west European populations of Reed Bunting in order to determine the extent of local adaptation relative to two important selection pressures often associated with speciation in birds: migration and diet. We show that, as expected by theory, migratory E. s. schoeniclus had longer and more pointed wings and a slightly smaller body mass than the resident subspecies, with the exception of E. s. lusitanica, which despite having rounder wings was the s…
Fishery-induced selection for slow somatic growth in European eel
2012
International audience; Both theoretical and experimental studies have shown that fishing mortality can induce adaptive responses in body growth rates of fishes in the opposite direction of natural selection. We compared body growth rates in European eel (Anguilla anguilla) from three Mediterranean stocks subject to different fishing pressure. Results are consistent with the hypotheses that i) fast-growing individuals are more likely to survive until sexual maturity than slow-growing ones under natural conditions (no fishing) and ii) fishing can select for slow-growing individuals by removing fast-growing ones. Although the possibility of human-induced evolution seems remote for a panmictic…