Search results for "vole"

Investigating the influence of climate changes on rodent communities at a regional-scale (MIS 1-3, southwestern France).

2016

25 pages; International audience; Terrestrial ecosystems have continuously evolved throughout the Late Pleistocene and theHolocene, deeply affected by both progressive environmental and climatic modifications, aswell as by abrupt and large climatic changes such as the Heinrich or Dansgaard-Oeschgerevents. Yet, the impacts of these different events on terrestrial mammalian communities arepoorly known, as is the role played by potential refugia on geographical species distributions.This study examines community changes in rodents of southwestern France between50 and 10 ky BP by integrating 94 dated faunal assemblages coming from 37 archaeologicalsites. This work reveals that faunal distributi…

Fluctuating food supply affects the clutch size of Tengmalm's owl independent of laying date.

1991

In western Finland, yearly median laying dates of Tengmalm's owls varied from 14 March to 27 April during 1973–1989 and were negatively correlated with the winter densities of voles. Yearly mean clutch sizes varied from 4.0 to 6.7 and were more closely related to the spring than to the winter densities of voles. The yearly mean clutch size decreased with yearly median laying date. The 3-year vole population cycle is typical of the study area. The start of egg-laying was earliest in the peak phase of the cycle (median laying date 22 March), when vole numbers are high during egg-laying, but decline rapidly to low numbers in the next autumn or winter. In the increase phase (1 April) vole abund…

La consapevolezza professionale del docente: resilienza e autoregolazione.

2016

Il contributo si inserisce all’interno del Progetto di Rilevante Interesse Na- zionale (PRIN, 2010/2011) dal titolo “Successo formativo, inclusione e coe- sione sociale: strategie innovative, ICT e modelli valutativi” (Coordinatore Scientifico Nazionale del Programma di Ricerca Prof. Gaetano Domenici), con particolare riferimento all’autovalutazione della consapevolezza del docente. L’autoregolazione consapevole è il processo che, avvalendosi di strumenti di ‘’self-assessment’’ permette di adottare comportamenti più efficaci nella vita personale e professionale. La consapevolezza dello scopo da perseguire promuove la capacità di effettuare scelte e compiere decisioni e, conseguen- tement…

Artificial selection for predatory behavior results in dietary niche differentiation in an omnivorous mammal

2021

AbstractThe diet of an individual is a result of the availability of dietary items and the individual’s foraging skills and preferences. Behavioral differences may thus influence diet variation, but the evolvability of diet choice through behavioral evolution has not been studied. We used experimental evolution combined with a field enclosure experiment to test whether behavioral selection leads to dietary divergence. We analysed the individual dietary niche via stable isotope ratios of nitrogen (δ15N) and carbon (δ13C) in the hair of an omnivorous mammal, bank vole, from 4 lines selected for predatory behavior and 4 unselected control lines. Predatory voles had higher hair δ15N values than…

Does risk of predation by mammalian predators affect the spacing behaviour of rodents? Two large-scale experiments.

2000

Predator-prey interactions between small mammals and their avian and mammalian predators have attracted much attention. However, large-scale field experiments examining small-mammal antipredatory responses under the risk of predation by mammals are rare. As recently pointed out, the scale of experiments may cause misleading results in studies of decision-making under predation risk. We studied the effect of small mustelid predators on the spacing behaviour of the gray-tailed vole (Microtus canicaudus) and the bank vole (Clethrionomys glareolus) in two separate field enclosure experiments. The experiments were conducted during the breeding season in North America and northern Europe, where s…

Genotype-by-Environment Interactions and Reliable Signaling of Male Quality in Bank Voles

2014

Predation on two vole species by a shared predator: antipredatory response and prey preference

2008

In prey communities with shared predators, variation in prey vulnerability is a key factor in shaping community dynamics. Conversely, the hunting efficiency of a predator depends on the prey community structure, preferences of the predator and antipredatory behavioural traits of the prey. We studied experimentally, under seminatural field conditions, the preferences of a predator and the antipredatory responses of prey in a system consisting of two Myodes species of voles, the grey-sided vole (M. rufocanus Sund.) and the bank vole (M. glareolus Schreb.), and their specialist predator, the least weasel (Mustela nivalis nivalis L.). To quantify the preference of the weasels, we developed a ne…

Phenotypic Flexibility in the Social Organization of Clethrionomys

1990

I review the flexibility of social organization and spacing behavior in Clethrionomys. This review is based on a 6-year comparative study and several experimental studies on cyclic populations of the bank vole, C. glareolus, in Central Finland. The social organization of Clethrionomys populations shows great flexibility during both the breeding and nonbreeding season, and is dependent on habitat patchiness, food availability, Predation, kinship, philopatry, and familiarity between individuals. The first three factors are most important in destabilizing a population, whereas the last three stabilize a population without exhausting its resources. Female territoriality can weaken in a producti…

A Comparative Study of Phenotypic Changes in Microtus Social Organization

1990

Monogamy, polygyny, and promiscuity have been found in populations of M. oeconomus and M. agrestis in different environmental situations in northern Finland. Thus the mating systems seem to be more variable both between and within species in Microtus than in Clethrionomys. Spacing behavior in Microtus caused a temporary decline in population density in mid-summer, but in Clethrionomys a decline occurred only in the beginning of the breeding season. Habitat quality affected spacing behavior in similar ways in Microtus and Clethrionomys but did not affect differences in breeding limitation. Despite the differences in population regulation, both Clethrionomys and Microtus populations cycle syn…

Morphométrie comparée de la première molaire inférieure de différentes populations d'Europe du Pléistocène supérieur du campagnol des steppes Microtu…

2006

The comparative analysis of the first lower molar (M1) of five populations of the steppe vole Microtus gregalis (Pallas, 1779) of the Upper Pleistocene from Romania and Germany has permitted to identify criteria characterising these populations. The proposed hypothesis in order to explain the observed variations between these populations is different chronological migrations of populations of M. gregalis from different climatic and geographical regions.