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Meadow Voles (meadow + vole)
Selected AbstractsMale and Female Meadow Voles, Microtus pennsylvanicus, Differ in Their Responses to Heterospecific/Conspecific Over-MarksETHOLOGY, Issue 9 2010Christian T. Vlautin Voles use runways, paths, and trails that may also be used by rabbits and mink. These shared areas could contain the scent marks of conspecifics and heterospecifics. Thus, it is likely that the scent marks of heterospecifics may overlap or be overlapped by those of voles, forming over-marks. Much is known about how voles respond to over-marks of two different conspecifics. However, we do not know how they would respond to an opposite-sex conspecific whose scent marks are in an over-mark with the scent marks of predator or the scent marks of a non-predator heterospecifics. We tested the hypothesis that meadow voles, Microtus pennsylvanicus, differ in their response to the scent mark of the opposite-sex conspecific if the scent mark was overlapped by that of a mink, a vole predator, or rabbit, a vole non-predator. We found that female but not male voles showed a preference for the scent marks of the opposite-sex conspecifics that were part of the mink-vole over-mark when compared to those of opposite-sex conspecifics that were not part of the over-mark. This preference by female voles was independent of whether the male vole was the top-scent donor or bottom-scent donor of the over-mark. Male and female voles showed no preference between the scent marks of the opposite-sex conspecifics whose marks were part of or not part of the rabbit-vole over-mark. Sex differences in the manner that meadow voles respond to rabbit-vole and mink-vole over-marks are discussed. [source] Social Dominance among Male Meadow Voles is Inversely Related to Reproductive SuccessETHOLOGY, Issue 10 2006Mark D. Spritzer Intrasexual selection can occur through direct aggressive interactions between males for access to females. We tested the relationship between social dominance and male reproductive success among meadow voles, Microtus pennsylvanicus. Dominance ranks of wild-caught males were determined using neutral arena trials, with the winner of two of three trials considered dominant. These males were then released into field enclosures and allowed to visit females housed in nestboxes for 8 wk, and males' home range sizes were determined using weekly grid trapping. Male reproductive success was determined using molecular paternity analysis (six microsatellite primers) for all pups born during the field experiment. Males with higher dominance ranks had larger home ranges. However, male dominance rank was not predictive of the number of total visits to females' nestboxes or the number of visits to each male's most frequently visited nestbox. Males that made more visits to nestboxes sired more litters. Males that had higher dominance ranks sired fewer litters. These results suggest that there is a reproductive disadvantage to having higher dominance rank among male meadow voles. [source] Meadow Voles (Microtus pennsylvanicus) and Prairie Voles (M. ochrogaster) Differ in Their Responses to Over-Marks from Opposite- and Same-Sex ConspecificsETHOLOGY, Issue 11 2000Raymond L. Woodward Jr Over-marking occurs when one individual deposits its scent mark on the scent mark of a conspecific. Previous studies have shown that meadow voles (Microtus pennsylvanicus) and prairie voles (M. ochrogaster) that were exposed to an over-mark of two same-sex conspecifics, later responded similarly to the top-scent mark but differed in their response to the bottom-scent mark. In the present study, we examined the responses of meadow voles and prairie voles to same-sex and mixed-sex over-marks to ascertain whether their responses reflect the different tactics which males and females in promiscuous (meadow voles) and monogamous (prairie voles) species use to attract opposite-sex conspecifics and to compete with same-sex conspecifics. Males and females of both species spent more time investigating the mark of the top-scent donor than that of the bottom-scent donor of an over-mark. Meadow voles exposed to a mixed-sex over-mark spent more time investigating the mark of the opposite-sex conspecific independently of whether it was from the top- or bottom-scent donor. In contrast, prairie voles spent more time investigating the mark of the opposite-sex donor if it was from the top-scent donor. These results suggest that: (i) over-marking serves a competitive function; (ii) the scent marks of individuals attract multiple mates in promiscuous species such as the meadow vole; and (iii) the scent marks of individuals establish and maintain pair bonds between familiar opposite-sex conspecifics in monogamous species such as the prairie vole. [source] Hormetic effects of gamma radiation on the stress axis of natural populations of meadow voles (Microtus pennsylvanicus)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2005Rudy Boonstra Abstract We tested the hypothesis that low doses of gamma radiation have beneficial, hormetic effects on the stress axis (the hypothalamic-pituitary-adrenocortical axis) of free-ranging meadow vole populations (Microtus pennsylvanicus). Voles were exposed to chronic gamma radiation from a 137Cs field irradiator. In isolated populations, voles received one of three treatments over a four-year period: Controls (0.19,0.42 ,Gy/h , levels that were 2,5X above background levels [0.1 ,Gy/h] and live-trapped in all years , 1982,1985), low doses (22.6 ,Gy/h , 50,200X background, live-trapped from November 1982,April 1985), or high doses (3,840 ,Gy/h , 40,000X background, live-trapped from November 1983,April 1985). Voles exposed to a low dose had levels of free and total corticosterone that were significantly higher than those in the control or high-dose groups. Differences in response to radiation between the sexes were apparent for maximum corticosterone-binding capacity, with females exposed to low doses having higher binding capacity than control or high-dose females, whereas males exposed to low doses had lower binding capacity than control or high-dose males. Low-dose voles had higher counts of neutrophils than either the controls or high-dose voles; hematocrit was greater in the controls than in irradiated voles. These results indicate that voles display a hormetic response to radiation, wherein low doses of an otherwise harmful agent produce a beneficial effect. The stimulation of the stress axis resulting in the increased secretion of glucocorticoids, which may protect against the excessive actions of the immune and inflammatory responses, may be a key mechanism producing this effect. [source] Male and Female Meadow Voles, Microtus pennsylvanicus, Differ in Their Responses to Heterospecific/Conspecific Over-MarksETHOLOGY, Issue 9 2010Christian T. Vlautin Voles use runways, paths, and trails that may also be used by rabbits and mink. These shared areas could contain the scent marks of conspecifics and heterospecifics. Thus, it is likely that the scent marks of heterospecifics may overlap or be overlapped by those of voles, forming over-marks. Much is known about how voles respond to over-marks of two different conspecifics. However, we do not know how they would respond to an opposite-sex conspecific whose scent marks are in an over-mark with the scent marks of predator or the scent marks of a non-predator heterospecifics. We tested the hypothesis that meadow voles, Microtus pennsylvanicus, differ in their response to the scent mark of the opposite-sex conspecific if the scent mark was overlapped by that of a mink, a vole predator, or rabbit, a vole non-predator. We found that female but not male voles showed a preference for the scent marks of the opposite-sex conspecifics that were part of the mink-vole over-mark when compared to those of opposite-sex conspecifics that were not part of the over-mark. This preference by female voles was independent of whether the male vole was the top-scent donor or bottom-scent donor of the over-mark. Male and female voles showed no preference between the scent marks of the opposite-sex conspecifics whose marks were part of or not part of the rabbit-vole over-mark. Sex differences in the manner that meadow voles respond to rabbit-vole and mink-vole over-marks are discussed. [source] Social Dominance among Male Meadow Voles is Inversely Related to Reproductive SuccessETHOLOGY, Issue 10 2006Mark D. Spritzer Intrasexual selection can occur through direct aggressive interactions between males for access to females. We tested the relationship between social dominance and male reproductive success among meadow voles, Microtus pennsylvanicus. Dominance ranks of wild-caught males were determined using neutral arena trials, with the winner of two of three trials considered dominant. These males were then released into field enclosures and allowed to visit females housed in nestboxes for 8 wk, and males' home range sizes were determined using weekly grid trapping. Male reproductive success was determined using molecular paternity analysis (six microsatellite primers) for all pups born during the field experiment. Males with higher dominance ranks had larger home ranges. However, male dominance rank was not predictive of the number of total visits to females' nestboxes or the number of visits to each male's most frequently visited nestbox. Males that made more visits to nestboxes sired more litters. Males that had higher dominance ranks sired fewer litters. These results suggest that there is a reproductive disadvantage to having higher dominance rank among male meadow voles. [source] Meadow Voles (Microtus pennsylvanicus) and Prairie Voles (M. ochrogaster) Differ in Their Responses to Over-Marks from Opposite- and Same-Sex ConspecificsETHOLOGY, Issue 11 2000Raymond L. Woodward Jr Over-marking occurs when one individual deposits its scent mark on the scent mark of a conspecific. Previous studies have shown that meadow voles (Microtus pennsylvanicus) and prairie voles (M. ochrogaster) that were exposed to an over-mark of two same-sex conspecifics, later responded similarly to the top-scent mark but differed in their response to the bottom-scent mark. In the present study, we examined the responses of meadow voles and prairie voles to same-sex and mixed-sex over-marks to ascertain whether their responses reflect the different tactics which males and females in promiscuous (meadow voles) and monogamous (prairie voles) species use to attract opposite-sex conspecifics and to compete with same-sex conspecifics. Males and females of both species spent more time investigating the mark of the top-scent donor than that of the bottom-scent donor of an over-mark. Meadow voles exposed to a mixed-sex over-mark spent more time investigating the mark of the opposite-sex conspecific independently of whether it was from the top- or bottom-scent donor. In contrast, prairie voles spent more time investigating the mark of the opposite-sex donor if it was from the top-scent donor. These results suggest that: (i) over-marking serves a competitive function; (ii) the scent marks of individuals attract multiple mates in promiscuous species such as the meadow vole; and (iii) the scent marks of individuals establish and maintain pair bonds between familiar opposite-sex conspecifics in monogamous species such as the prairie vole. [source] Disturbance and habitat use: is edge more important than area?OIKOS, Issue 1 2006Alissa E. Moenting In their efforts to maximize fitness while reducing the probability of dying, animals must decide which patches to forage in, when to forage, and how long to forage in each patch. Each decision will be modified by habitat and habitat disturbance. We evaluate the effects of habitat disturbance on foraging behaviour by imagining an initially homogeneous environment that is altered to create patches of different sizes. Disturbance increases predation risk, or otherwise alters patch profitability. Foragers can respond by changing their pattern of foraging, or by reducing their activity. We develop predictions for each scenario. We then test the predictions with data on the abundance and foraging activity of meadow voles (Microtus pennsylvanicus) in and around four sizes of circular disturbed patches. We created the patches by mowing vegetation in an abandoned hay field in northern Ontario, Canada. The treatments had no effect on vole density, and there was no consistent relationship between vole activity and distance from the edge of disturbed patches. Incidental predation of sunflower seeds, our measure of vole foraging behaviour, declined linearly with increasing patch circumference (edge). Seed consumption by meadow voles, and predation by voles on lower food levels, correlates with the length of edge habitat rather than with the area disturbed. Adaptive behaviour can thereby explain edge effects that, under current priorities emphasizing area, would appear at odds with conservation ecology. [source] Analysis of Capture,Recapture Models with Individual Covariates Using Data AugmentationBIOMETRICS, Issue 1 2009J. Andrew Royle Summary I consider the analysis of capture,recapture models with individual covariates that influence detection probability. Bayesian analysis of the joint likelihood is carried out using a flexible data augmentation scheme that facilitates analysis by Markov chain Monte Carlo methods, and a simple and straightforward implementation in freely available software. This approach is applied to a study of meadow voles (Microtus pennsylvanicus) in which auxiliary data on a continuous covariate (body mass) are recorded, and it is thought that detection probability is related to body mass. In a second example, the model is applied to an aerial waterfowl survey in which a double-observer protocol is used. The fundamental unit of observation is the cluster of individual birds, and the size of the cluster (a discrete covariate) is used as a covariate on detection probability. [source] | ||||||||||