The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
T Lode - One of the best experts on this subject based on the ideXlab platform.
-
European mink-Polecat hybridization events: Hazards from natural process?
The Journal of heredity, 2005Co-Authors: T Lode, G. Guiral, D. PeltierAbstract:Determining the significance of hybridization events raises essential issues both in conservation and in evolutionary biology. Here, we report a genetic investigation of sympatric Polecat and endangered European mink populations. Although the two species were morphologically very similar, the European mink and the Polecat were easily discriminated from allozymes and microsatellites and showed a high level of private alleles (effective number of alleles: mink=1.45 and Polecat=3.09). Nevertheless, the allozymic polymorphism remained lower in the European mink (4 loci, 10.5%) than in Polecat (9 loci, 23.7%). Similarly, from microsatellite data, the polymorphism only reached 36% at 0.99 in the European mink; whereas in the Polecat, the polymorphism reached 82% at 0.99. Natural hybridization events between two native species were detected. Because of the low fertility of hybrids, interbreeding could be regarded as producing "hybrid sink" that leads to a progressive assimilation of mink by Polecat. Nonetheless, pure mink populations inhabited streams in western France, and hybridization events were only detected in areas where mink were rare and now presumed disappeared. Rather than revealing the poor efficiency of the specific recognition system, our results suggest that hybridization is associated with the scarcity of mating partners.
-
Genetic divergence without spatial isolation in Polecat Mustela putorius populations
Journal of Evolutionary Biology, 2001Co-Authors: T LodeAbstract:Understanding how genetic divergence could exist without spatial isolation is a fundamental issue in biology. Although carnivores have previously been considered as having a weak genetic variability, Polecats Mustela putorius from eight distinct populations exhibited both a strong polymorphism (17.5-22.5%) and a substantial allele effective number reaching Ne = 1.12. Heterozygosity ranging from Ho = 0.031-0.063 significantly differed among populations, while the mean FIS averaging 0.388 stressed a real deficiency of heterozygotes. Observed heterozygosity levels among populations did not correlate with any habitat types but were clearly associated with habitat diversity index. The habitat structure in Polecat home range corresponded to habitat mosaic structure in which discrete habitat types alternated causing multifactorial constraints that may favour heterozygosity. Allozymic frequencies within populations did not vary with dominant habitat. But in the Tyrosinase-1, the rare homozygote BB, resulting in a 'dark' phenotype, was found much more in deciduous woods than the homozygote AA showing the 'typical' pattern. Thus, the genetic basis for a character differentiation was here evidenced in a remarkable situation without spatial isolation. Further, the very low proportion of heterozygotes for this locus suggests a disruptive effect and supports the prediction of intermediate phenotypes being at a disadvantage. This heterozygote deficit may also result from an assortative mating intra phenotype (homogamy). The divergence in Polecat phenotypes showed that genetic differentiation can be induced by subtle variations in environment, a situation that is likely to be frequent in most natural populations, and emphasized the adaptive nature of habitat preference.
-
Genetic heterozygosity in Polecat Mustela putorius populations from western France.
Hereditas, 1998Co-Authors: T LodeAbstract:Allozymic variations were investigated in 49 European Polecats Mustela putorius from Western France by starch gel electrophoresis. Out of 31 surveyed loci, eight (25.8%) were shown polymorphic and observed heterozygosity averaged 0.057. Deviations from Hardy-Weinberg equilibrium and heterozygote deficiency suggest that populations were not in panmixia. Heterozygotes for two loci or more totalled 42.9% of individuals. Thus, although carnivores were previously considered as less variable, Polecat populations from Western France showed a high genetic variability.
-
Environmental factors influencing habitat exploitation by the Polecat Mustela putorius in western France
Journal of Zoology, 1994Co-Authors: T LodeAbstract:Variation in habitat use was studied by radiotracking 11 Polecats Mustela putorius in two wetlands in western France. Habitat selection showed a clear seasonality. Marshes were the most exploited habitat in spring while woods were mainly used in the coldest months and meadows were frequented in summer and winter. An analysis of scats showed that diet correlated with habitat utilization. The proportions of bank voles Clethrionomys glareolus, and meadow voles Microtus sp. were, respectively, related to the use of woods and meadows, while amphibians (mainly Rana dalmatina and Bufo bufo) were associated with marshes. Availabilities of rodents, assessed monthly by trapline success, were also significantly correlated to their occurrences. In contrast, no correlations were found between larger prey, such as brown rats Rattus norvegicus and rabbits Oryctolagus cuniculus, and any habitats or their abundance in the field. The occurrences of these prey and of some minor resources, such as shrews and birds, were correlated most with meteorological factors. The exploitation of marshes and amphibians increased when small rodents declined. Therefore, in the Polecat, habitat selection was mostly influenced by trophic factors. Dietary diversity was greater in spring when food resources decreased, suggesting that Polecats were optimal foragers. The study has emphasized that the Polecat is a generalist feeder.
Maciej T. Krajcarz - One of the best experts on this subject based on the ideXlab platform.
-
The first radiocarbon dated steppe Polecat (Mustela eversmanii) from the Pleistocene of Poland
Quaternary International, 2015Co-Authors: Maciej T. Krajcarz, Tomasz Goslar, Adam NadachowskiAbstract:The mandible of a steppe Polecat was found during excavation in Deszczowa Cave (Czestochowa Upland, southern Poland) in 2011. Direct radiocarbon dating gave an age of 21 920 ± 150 BP (not calibrated), indicating the earliest part of the Last Glacial Maximum (MIS 3/MIS 2). The association of the steppe Polecat with other steppe and tundra taxa from the same layer confirms that this species was an element of the widespread steppe-tundra ecosystem in East Europe during Late Pleistocene. There is no evidence of sousliks in the layer with the steppe Polecat fossil.
Thierry Lode - One of the best experts on this subject based on the ideXlab platform.
-
Reconnaissance de la parentèle en fonction de la familiarité chez un mustélidé solitaire, le putois européen Mustela putorius [Kin recognition versus familiarity in a solitary mustelid, the European Polecat Mustela putorius]
Comptes Rendus Biologies, 2008Co-Authors: Thierry LodeAbstract:The aim of this experimental study was to investigate kin discrimination in the Polecat and to analyse the ontogeny of interactions. Juvenile Polecats (ten males and nine females) had been raised under four distinct experimental conditions: 1, kin, familiar; 2, kin, unfamiliar; 3, non-kin, familiar; 4, non-kin, unfamiliar. During dyadic encounters between Polecats in neutral enclosures, the number of positive (tolerance), negative (aggression), intermediate (intimidation), and neutral interactions (no direct interactions) were recorded at two different ages of the animals (50 and 70 days old). Male-male encounters were characterised by more aggressive behaviour than female-female ones. The proportion of these negative interactions increased with age, while the proportion of positive interactions decreased. Although aggressive behaviours varied among groups, the reaction did never differ with the kinship. Kin selection theory provides successful explanations for a wide range of phenomena, but our results suggest that multiple mechanisms running simultaneously might be involved in social behaviours. Familiarity clearly influenced the social behaviour of Polecats and might be involved in a kin facilitation effect favouring interactions. Animals raised together demonstrated more positive and less negative interactions, so that, despite the individualistic way of life of the Polecat, familiarisation may result in more tolerance, emphasising that solitary species may provide significant information on social life. Anyway, familiarisation in Polecat may be regarded as a cognitive form of recognition.
-
Kin recognition versus familiarity in a solitary mustelid, the European Polecat Mustela putorius.
Comptes rendus biologies, 2008Co-Authors: Thierry LodeAbstract:The aim of this experimental study was to investigate kin discrimination in the Polecat and to analyse the ontogeny of interactions. Juvenile Polecats (ten males and nine females) had been raised under four distinct experimental conditions: 1, kin, familiar; 2, kin, unfamiliar; 3, non-kin, familiar; 4, non-kin, unfamiliar. During dyadic encounters between Polecats in neutral enclosures, the number of positive (tolerance), negative (aggression), intermediate (intimidation), and neutral interactions (no direct interactions) were recorded at two different ages of the animals (50 and 70 days old). Male-male encounters were characterised by more aggressive behaviour than female-female ones. The proportion of these negative interactions increased with age, while the proportion of positive interactions decreased. Although aggressive behaviours varied among groups, the reaction did never differ with the kinship. Kin selection theory provides successful explanations for a wide range of phenomena, but our results suggest that multiple mechanisms running simultaneously might be involved in social behaviours. Familiarity clearly influenced the social behaviour of Polecats and might be involved in a kin facilitation effect favouring interactions. Animals raised together demonstrated more positive and less negative interactions, so that, despite the individualistic way of life of the Polecat, familiarisation may result in more tolerance, emphasising that solitary species may provide significant information on social life. Anyway, familiarisation in Polecat may be regarded as a cognitive form of recognition. To cite this article: T. Lode?, C. R. Biologies 331 (2008). © 2008.
-
Ethology / Éthologie Kin recognition versus familiarity in a solitary mustelid, the European Polecat Mustela putorius
2008Co-Authors: Thierry LodeAbstract:The aim of this experimental study was to investigate kin discrimination in the Polecat and to analyse the ontogeny of interactions. Juvenile Polecats (ten males and nine females) had been raised under four distinct experimental conditions: 1, kin, familiar; 2, kin, unfamiliar; 3, non-kin, familiar; 4, non-kin, unfamiliar. During dyadic encounters between Polecats in neutral enclosures, the number of positive (tolerance), negative (aggression), intermediate (intimidation), and neutral interactions (no direct interactions) were recorded at two different ages of the animals (50 and 70 days old). Male–male encounters were characterised by more aggressive behaviour than female–female ones. The proportion of these negative interactions increased with age, while the proportion of positive interactions decreased. Although aggressive behaviours varied among groups, the reaction did never differ with the kinship. Kin selection theory provides successful explanations for a wide range of phenomena, but our results suggest that multiple mechanisms running simultaneously might be involved in social behaviours. Familiarity clearly influenced the social behaviour of Polecats and might be involved in a kin facilitation effect favouring interactions. Animals raised together demonstrated more positive and less negative interactions, so that, despite the individualistic way of life of the Polecat, familiarisation may result in more tolerance, emphasising that solitary species may provide significant information on social life. Anyway, familiarisation in Polecat may be regarded as a cognitive form of recognition. To cite this article: T. Lode, C. R. Biologies 331 (2008).
-
ethology ethologie kin recognition versus familiarity in a solitary mustelid the european Polecat mustela putorius
2008Co-Authors: Thierry LodeAbstract:The aim of this experimental study was to investigate kin discrimination in the Polecat and to analyse the ontogeny of interactions. Juvenile Polecats (ten males and nine females) had been raised under four distinct experimental conditions: 1, kin, familiar; 2, kin, unfamiliar; 3, non-kin, familiar; 4, non-kin, unfamiliar. During dyadic encounters between Polecats in neutral enclosures, the number of positive (tolerance), negative (aggression), intermediate (intimidation), and neutral interactions (no direct interactions) were recorded at two different ages of the animals (50 and 70 days old). Male–male encounters were characterised by more aggressive behaviour than female–female ones. The proportion of these negative interactions increased with age, while the proportion of positive interactions decreased. Although aggressive behaviours varied among groups, the reaction did never differ with the kinship. Kin selection theory provides successful explanations for a wide range of phenomena, but our results suggest that multiple mechanisms running simultaneously might be involved in social behaviours. Familiarity clearly influenced the social behaviour of Polecats and might be involved in a kin facilitation effect favouring interactions. Animals raised together demonstrated more positive and less negative interactions, so that, despite the individualistic way of life of the Polecat, familiarisation may result in more tolerance, emphasising that solitary species may provide significant information on social life. Anyway, familiarisation in Polecat may be regarded as a cognitive form of recognition. To cite this article: T. Lode, C. R. Biologies 331 (2008).
-
can low densities of carnivores result in genetic depletion an investigation within french Polecat populations
Journal of Animal Breeding and Genetics, 2006Co-Authors: Thierry LodeAbstract:Summary Carnivores as top predators are commonly found in relatively low densities even in optimal habitats. Despite a lack of empirical studies, it could be suspected that long-term low density could result in genetic depletion. The genetic structure of European Polecat Mustela putorius natural populations was investigated by allozyme electrophoresis in five distinct areas. Density estimates significantly differed among sites from 0.17 to 0.83 individuals/km 2 with an average of 0.56 individuals per km 2 , resulting in a scattered distribution. Genetic structure varied among distinct populations both in number of polymorphic loci and heterozygosity. Polecats from Brittany revealed a very low observed heterozygosity (HO ¼ 0.028) whereas mean heterozygosity reached HO ¼ 0.072 in
François Spitz - One of the best experts on this subject based on the ideXlab platform.
-
Spatial behaviour of European minkMustela lutreola and PolecatMustela putorius in southwestern France
Mammal Research, 2008Co-Authors: Pascal Fournier, Christian Maizeret, Stéphane Aulagnier, Christine Fournier-chambrillon, Nicolas Ilbert, François SpitzAbstract:The European mink Mustela lutreola Linnaeus, 1761 and the European Polecat Mustela putorius Linnaeus, 1758 are sympatric in southwestern France. They are related species but the former is highly threatened whereas the latter maintains good populations. Nine European mink and 14 Polecats were radiotracked in the Landes de Gascogne region to compare their space use and to identify appropriate conservation measures for the European mink. Resting animals were located once a day and active animals were tracked by continuous monitoring. European mink had linear home ranges whose sizes were larger than predicted by Johnson’s model (mean±SD=2971±1888 ha in males and 257±113 ha in females). They travelled long inter-day distances (1.4±1.9 km in males and 0.4±0.6 km in females). Polecats had home ranges of various shapes (linear, circular or combined) and their sizes were consistent with Johnson’s model (707±779 ha in males and 51±58 ha in females). They also had shorter inter-day distances than mink (0.7±0.9 km in males and 0.2±0.4 km in females). However male Polecats had longer activity bouts than male mink. Thus European mink exhibit large movements between small and distant activity areas while Polecats compensate for their smaller range by a higher activity in restricted areas. The behaviour of the European mink appears to be an adaptation to habitats scattered over linear ranges. This extensive use of space suggests that conservation of this endangered species cannot be achieved in the confinement of Europe’s natural reserves. Conservation plans should aim at maintaining high quality habitats along entire river networks and ensuring safe movements for the animals, preventing particularly the risk of collisions with vehicles.
-
Habitat utilization by sympatric European minkMustela lutreola and PolecatsMustela putorius in south-western France
Acta Theriologica, 2007Co-Authors: Pascal Fournier, Christian Maizeret, David Jimenez, Jean-pierre Chusseau, Stéphane Aulagnier, François SpitzAbstract:The European mink Mustela lutreola Linnaeus, 1761 and the European Polecat Mustela putorius Linnaeus, 1758 are related species sympatric in southwestern France. The European mink is rapidly disappearing whereas the Polecat maintains good populations. Seasonal habitat use of both species was compared in the Landes de Gascogne region to identify if some vulnerability factors of the European mink were associated with habitats occupied by this mustelid. Potential habitats were mapped using a satellite picture and 12 main types of habitats were defined. Animal locations were recorded by radiotracking 9 European mink and 14 Polecats from March 1996 to August 1999. Resting animals were located by triangulation, and, when possible, resting places were described. Animals in activity were tracked by continuous monitoring. Data collected revealed a strong preference of European mink for flooded habitats, particularly open marshes, flooded woodlands and moorlands. They seldom left the corridor of the riparian forest and their resting places were mainly in flooded environments, above ground (under herbs or bushes) or in cavities between tree roots. European Polecats were less tightly linked to wetlands. Most of their locations were in the pine forests outside the valleys and their resting places were mainly in burrows. The strong specialisation of European mink in aquatic habitats is probably one of the main reasons for its decline because wetlands suffer drastic damages throughout all of its range. Maintaining adequate water levels is crucial for satisfying habitat requirements of mink.
-
Habitat utilization by sympatric European mink Mustela lutreola and Polecats Mustela putorius in south-western France
Acta Theriologica, 2007Co-Authors: Pascal Fournier, Christian Maizeret, David Jimenez, Jean-pierre Chusseau, Stéphane Aulagnier, François SpitzAbstract:The European mink Mustela lutreola Linnaeus, 1761 and the European Polecat Mustela putorius Linnaeus, 1758 are related species sympatric in southwestern France. The European mink is rapidly disappearing whereas the Polecat maintains good populations. Seasonal habitat use of both species was compared in the Landes de Gascogne region to identify if some vulnerability factors of the European mink were associated with habitats occupied by this mustelid. Potential habitats were mapped using a satellite picture and 12 main types of habitats were defined. Animal locations were recorded by radiotracking 9 European mink and 14 Polecats from March 1996 to August 1999. Resting animals were located by triangulation, and, when possible, resting places were described. Animals in activity were tracked by continuous monitoring. Data collected revealed a strong preference of European mink for flooded habitats, particularly open marshes, flooded woodlands and moorlands. They seldom left the corridor of the riparian forest and their resting places were mainly in flooded environments, above ground (under herbs or bushes) or in cavities between tree roots. European Polecats were less tightly linked to wetlands. Most of their locations were in the pine forests outside the valleys and their resting places were mainly in burrows. The strong specialisation of European mink in aquatic habitats is probably one of the main reasons for its decline because wetlands suffer drastic damages throughout all of its range. Maintaining adequate water levels is crucial for satisfying habitat requirements of mink.
C J Topping - One of the best experts on this subject based on the ideXlab platform.
-
exposure of stone marten martes foina and Polecat mustela putorius to anticoagulant rodenticides effects of regulatory restrictions of rodenticide use
Science of The Total Environment, 2018Co-Authors: Morten Elmeros, Pia Lassen, Rossana Bossi, C J ToppingAbstract:Abstract When anticoagulant rodenticides (ARs) are used to control rodent populations there is also a widespread secondary exposure of non-target predators to ARs. To reduce secondary exposure, regulatory restrictions in AR usage were tightened in Denmark in 2011. The restrictions included the cessation of AR use for plant protection and any use away from buildings, as well as limitations in private consumers' access to ARs. To quantify and evaluate the efficiency of the regulatory measures to reduce secondary exposure, we analysed ARs in liver tissue from 40 stone martens ( Martes foina ) and 40 Polecats ( Mustela putorius ) collected before and 31 stone martens and 29 Polecats collected after the restrictions were imposed. No declines in the prevalence ARs were detected following the regulatory restrictions in either stone marten (Before: 98%, After: 100%) or Polecat (Before: 93%, After: 97%). The total AR concentration was higher in stone martens than in Polecats in both sampling periods. Between the two sampling periods, the total AR concentrations in the mustelids increased (P The regulatory restrictions in AR usage did not reduce exposure of non-target stone martens and Polecats. The temporal and spatial patterns of AR concentrations in predators indicate that chemical rodent control in and around buildings is the dominant source for the exposure of non-target predators in intensively human-dominated landscapes in Denmark. The results suggest that non-chemical methods for rodents control at buildings are necessary to prevent widespread secondary AR exposure of predators in human modified landscapes.