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1

Estimation of home-range size in small rodents for any truncation of sampling data

100%
Wierzbowska T.
Polish Ecological Studies
|
1994
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tom 20
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nr 3-4
2

Interactions driving the population cycle of Arctic small rodents

75%
Garding L.
Polish Journal of Ecology
|
2005
|
tom 53
|
nr 4
The cyclicity of Arctic populations of small rodents is a subject with a long history and a large literature (Batzli,1992) in which the question ‘What drives the cycle?’ has received many answers, among them that the source of the cycle is either rodent interaction with food or the interaction with predators or both. Another question concerns the confinement of the cycle to Arctic conditions. The paper by Gårding (2000) presented a simple mathematical model of the combined predator-prey-food interaction based on a general eater-food interaction in which cycle length is an explicit decreasing function of the average birth rate of eaters. In the combined interaction, the cycle length is the same function of the sum of the average birth rates of predators and prey. Numerical fits of these models make it possible to answer the questions above. The results are that the short 3–5 year cycles of the Arctic rodents: lemming (Lemmus lemmus) and vole (Microtus agrestis) are mainly driven by interaction with food while the ten year cycle of the Canadian snowshoe hare (Lepus americanus), is driven by interaction with its predator – lynx. Rodents in the Arctic live and breed in burrows and experience predation pressure when surfacing. This explains their interaction with food. The greater variety and easier availability of food in a temperate climate accounts for a missing rodent interaction with food. The paper starts with a presentation of the eater-food interaction model itself, its simple but unfamiliar mathematics and its points of credibility. At the end of the paper some current hypotheses about the nature of the rodent cycle are seen in the light of the model used here.
3
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Content available

Current data about the reservoir for Borrelia burgdorferi S.L. in the district of Mazury Lakes, Poland

75%
Sinski E., Pawelczyk A., Karbowiak G.
Wiadomości Parazytologiczne
|
1998
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tom 44
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nr 3
4

Bank vole biology: recent advances in the population biology of a model species

75%
Bujalska G., Hansson L.
Polish Journal of Ecology
|
2000
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tom 48
|
nr Suppl.
5

Geographic and seasonal variability in feeding behaviour of a small herbivorous rodent

63%
Sassi P. L., Borghi C. E., Dacar M. A., Bozinovic F.
Acta Theriologica
|
2011
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tom 56
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nr 1
Foraging strategies have traditionally been modelled as a result of food selection in response to one factor, as for instance resource availability, deterrent compounds or nutrients. Thus, a trade-off is assumed between plasticity (generalist strategy) and efficiency (specialist strategy). Nevertheless, several studies have demonstrated that animals cope behaviourally with food supply variation. For instance, desert-dwelling rodents partially compensate for nutritional bottlenecks through diet selection. The aim of our study was to test how foraging behaviour matches spatial and temporal variations in the trophic environment and how modelling hypotheses help us to understand the resultant foraging strategy. Our animal study model was the small cavy Microcavia australis, a widely distributed herbivorous rodent. Fieldwork was carried out in four places, in wet and dry seasons. We found significant differences in plant cover, plant diversity and niche breadth, and diet selection revealed a complex foraging strategy. M. australis shows a behavioural repertoire that exceeds single-criterion categories; therefore, we appeal to theoretical models that consider ecological and physiological perspectives. We classified the small cavy as a facultative specialist displaying a thoroughly opportunistic strategy based on the plasticity of the behavioural phenotype. We finally discuss the evolutionary relevance of our results and propose further investigation avenues.
6

Effectiveness of Korean pine (Pinus koraiensis) seed dispersal by small rodents in fragmented and primary forests

63%
Yang Y., Yi X.
Polish Journal of Ecology
|
2011
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tom 59
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nr 2
The effectiveness of dispersers on seeds of Korean pine (Pinus koraiensis Siebold et Zuccarini) was investigated in three fragmented stands and one primary stand. The proportion of Korean pine trees was less than 7% in the fragmented stands but more than 90% in primary stand. Five estimates related seed dispersal (proportion of removed seeds, scatter-hoarded seeds, cache dynamics, dispersal distance and microhabitat) were assessed to see the effect of forest fragmentation on the probability of seed dispersal of Korean pine seeds. Our results indicated fast seed harvest of Korean pine by small rodents at the seed stations and no difference among the four stands. Scatter-hoarding rodents were potentially important in promoting natural regeneration of Korean pine as revealed by high proportion of seed removal (up to 50%), short seed lifetime from the seed release locations and lower proportion of seeds remained on the ground surface. Although a proportion of seeds were scatter-hoarded in fragmented stands, no seedling successfully established due to heavy predation. Dispersal distances were strongly left-skewed in fragmented stands, indicating that fragmentation is likely to be disadvantageous for longer distance dispersal. The effective dispersal was suffered from a very heavy cost as accompanied by a great portion of seed predation and lower level of scatter-hoarded seeds. Failing to see seedling establishment in fragmented stands rather than in primary stand indicated that fragmentation and deforestation have negative effects on dispersal behavior and consequently seed destination. Artificial tree plantation and pinecone protection are highly recommended for Korean pine regeneration.
7

Population ecology of small mammals in a floodplain forest in the central part of the Elbe River

63%
Haferkorn J.
Polish Ecological Studies
|
1994
|
tom 20
|
nr 3-4
8

Why do some young voles stop growing?

63%
Gliwicz J.
Polish Ecological Studies
|
1994
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tom 20
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nr 3-4
9

Dispersal in bank voles: benefits to emigrants or to residents?

63%
Gliwicz J.
Acta Theriologica
|
1993
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tom 38
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nr 1
The paper revises Lhe recent hypotheses on the evolution of dispersal behaviour in voles, namely Emigrant Fitness Hypothesis (EFH) versus Resident Fitness Hypo­thesis (RFH), on the basis of 3-year study on dispersal of Bank voles Clethrionomys glareolus (Schreber, 1780). The studied populations lived in three types of habitats: a small island, a rich alder forest (both optimal habitats) and small patches of woods (suboptimal habitat). The island population was treated as a control for dispersal occuring in two other populations. Young voles born in the first litters of the year commonly dispersed from the optimal natal habitat into the vacant suboptimal habitat. These immigrants had higher reproductive success in the new habitat than their counterparts in the control habitat. Residents, which were parents and younger siblings of emigrants, also benefitted from the absence of dispersers: their home ranges were less crowded and food depleted, and the rates of maturation were higher than in the control habitat. The gain in the inclusive fitness of matrilines with dispersing young is postulated as a ultimate cause for dispersal. A mutual overlap in predictions of EFH and RFH is indicated.
10

Trypanosoma [Herpetosoma] microti Laveran et Pettit, 1909 in the social vole, Microtus socialis [Pallas, 1771] from Ukraine

63%
Wita I., Karbowiak G., Czaplinska U.
Acta Parasitologica
|
2003
|
tom 48
|
nr 3
This study reports the light and electron microscopic examination of Trypanosoma (Herpetosoma) microti from the social vole (Microtus socialis, Rodentia) from the steppe near Askania Nova, Ukraine. Bloodstream trypomastigotes were identified morphometrically from 100 specimens from blood of 4 infected social voles. Body length ranged from 13.88-27.79 µm, and width from 0.53-2.06 µm, with the free flagellum 5.12-11.69 µm long. The trypanosomes were comparable to Trypanosoma microti from the short-tailed vole, Microtus agrestis, and the root vole, Microtus oeconomus. Cultured epimastigotes exhibited typical ultrastructural features similar to those of stercorarian and salivarian groups.
11

Modulating factors of the energetic effectiveness of huddling in small mammals

63%
Canals M., Rosenmann M., Novoa F. F., Bozinovic F.
Acta Theriologica
|
1998
|
tom 43
|
nr 4
Huddling is effective in decreasing metabolic rate permitting energy saving. However, this decrease varies among different species depending on physical, physio­logical and behavioral characteristics of the huddled individuals. Following a general model we analyzed the effects of ambient temperature, thermal conductance and ontogeny on the huddling effectiveness (energy saving level from huddling behaviour) in white mice Mus musculus. Also, we studied the effects of thermal conductance by using the Sigmodontine Abrothrix andinus as a model organism, To put our results in a general context we analyzed literature data of huddling of several species of rodents at different temperatures. No effects of temperature and thermal conductance was detected. However, based on literature data, we found that at temperatures lower or near thermoneutrality the huddling effectiveness decrease, Also, the huddling effectiveness depends on the stage of development. Temperature probably affects the intensity of huddling, while changes in huddling effectiveness at early stages of development are likely consequences of structural (morphological) changes during the ontogeny. In this sense, it appears that the capacity to change the body form is and individual structural constraint which is extended to the huddling group.
12

Population fluctuations of the wood lemming Myopus schisticolor in Eastern and Western Finland

63%
Eskelinen O., Sulkava P., Sulkava R.
Acta Theriologica
|
2004
|
tom 49
|
nr 2
From 1982 to 2003 we studied fluctuations in populations of the wood lemming Myopus schisticolor (Liljeborg, 1844) in the Heinävesi (eastern Finland) and Keuruu regions (western Finland) by counting field signs and dead animals in standardized field surveys. We compared the population fluctuations of lemmings to those of other voles, owls and small mustelids in these regions. The lemming population in Heinävesi fluctuated regularly in 3-year cycles and in synchrony with the field vole popu- lation. i Populations of owls also fluctuated in synchrony with wood lemming and field vole populations. In the Keuruu region, oscillations in the wood lemming population were irregular, and neither lemming and vole populations nor lemming and owl populations were correlated. Although direct mechanistic evidence is lacking, specialist predators such as weasels and owls probably cause the cyclicity in the field vole and wood lemming populations in the Heinävesi area. On the other hand, scarcity of high-quality habitats, unfavourable winter weather conditions and generalist predators may prevent the development of cyclicity in the wood lemming population of Keuruu.
13

Artificial tunnels as a method for studying populations of small rodents

63%
Andrzejewski R., Badaszek M., Lopucki R., Mroz I., Pastucha A., Prasowska M., Wawrzak D.
Polish Journal of Ecology
|
2007
|
tom 55
|
nr 3
A method was proposed for studying population density, microhabitat preference, daily activity and seasonal activity in small rodents. In this method, artificial tunnels (PVC pipes) imitating a natural system of burrows were applied. Their use by rodents was recorded by means of the electronic counters provided with a photoelectric cell. The study was conducted in an alder swamp 110 years old, located in the Kampinos National Park (52°25’N, 20°53’E) during 2003–2005. In this area, the bank vole Clethrionomys glareolus (Schreber, 1780) accounted for 90–99% of the captured rodents. The use of the tunnels by rodents (the number of passages) did not depend on their length within a range of 1–8 m applied in the experiment (P = 0.22). The tunnels were used by day and night, at the highest rate in the evening and at night. The use of tunnels increased when a bait was exposed in the vicinity (P = 0.001). It was positively correlated with population density (estimated with the CMR technique), and varied from season to season (in spring, summer, and autumn). The formula: density = 0.1717 + 0.0304 × mean number of passages per day, enabled the estimation of population density based on the number of passages through the tunnels. It has been found that a single tunnel was typically used by 5 individuals (mean 4.6 individuals, SD = 1.8). The location of tunnels had a significant effect on their use. Tunnels connecting fallen logs or bases of alders (hummocks) were more frequented than those leading to shrubby areas (P <0.000) or to microhabitats covered with herbaceous vegetation (P <0.001). This method enabled a multisided analysis of the behaviour of rodents at a minimum interference in the life of animals. Thanks to the application of electronic counters of passages, it was possible to obtain easily a large number of data. It is proposed to mark rodents with electronic transponders in the future studies to identify the individuals using artificial tunnels. This method could replace the methods used so far in the studies of small rodents, requiring trapping (CMR) or radio-telemetry.
14

Metabolism of olomoucine, roscovitine, and bohemine in small laboratory rodents

63%
Chmela Z., Vesely J., Lemr K., Hanus J., Havlicek L., Rypka M., Krystof V., Ulrichova J., Walterova D., Fuchsova L., Lukes J., Kolarova H., Strnad M., Lenobel R.
Cellular and Molecular Biology Letters
|
1998
|
tom 03
|
nr 3
15

The roles of small rodents in creating patchy environments

63%
Ostfeld R. S., Lewin N., Schnurr J., Pickett S. T. A., Canham C. D.
Polish Ecological Studies
|
1994
|
tom 20
|
nr 3-4
16

Prey selection of the least weasel Mustela nivalis in the laboratory

63%
Pekkarinen P., Heikkila J.
Acta Theriologica
|
1997
|
tom 42
|
nr 2
Prey individuals representing the bank vole Clethrionomys glareolus and the field vole Microtus agrestis were presented in pairs to male and female least weasels Mustela nivalis Linnaeus, 1766 in the laboratory. The voles were placed in two randomly selected boxes out of 8 boxes, which were connected to an arena housing the weasel. For each trial we recorded the finding, killing and eating order of the two prey individuals. Mate weasels tended to kill bank voles before field voles, and female weasels preferred to eat the bank vole first. Both sexes selected juvenile bank voles as the first prey to eat.
17
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Content available

Occurrence of intestinal microparasites in small rodents

51%
Perec-Matysiak A., Lesnianska K., Bunkowska-Gawlik K., Hildebrand J.
Annals of Parasitology
|
2016
|
tom 62
|
nr Suppl.
18

Assessment of Akodon cursor (Rodentia, Sigmodontinae) as permissive host to Schistosoma mansoni infection: morphology of adult worms

51%
Machado-Silva J. R., Heisler Neves R., Rodrigues-Silva R., Figueiredo de Oliveira R. M., Maldonado Junior A.
Acta Parasitologica
|
2011
|
tom 56
|
nr 2
The natural infection with parasitic helminths is common in wild rodent populations. Once such interactions are better understood in the laboratory, it will be more feasible to extend the findings to infected hosts in nature. The flukes recovered from laboratory-infected Akodon cursor at 63 days post-infection were stained with hydrochloric carmine and individually mounted on glass slide as whole-mounts. Light and laser scanning confocal microscopy studies of adult male and female Schistosoma mansoni are reported. The parasites were examined morphologically and biometrically, which was obtained in a digital system for image analysis. Parameters used were: tegument thickness, digestive, excretory and reproductive systems. The overall conclusion of this experiment is that the morphological features of adult worm were similar to laboratory mice. It has been confirmed that the grass mouse is a permissive host to S. mansoni infection.
19

Growth studies in Akodon dolores [Rodentia: Muridae] in captivity

51%
Piantanida M., Barrantes G. E.
Acta Theriologica
|
1998
|
tom 43
|
nr 2
Growth processes in Akodon dolores Thomas, 1916 were studied by measuring morphological variables in a captive colony of 1500 specimens. Sex differences were not statistically significant. Most variables fitted to a sigmoid function and showed the same behaviour up to 3 months of age: an acceleration in growth up to the first month, followed by a deceleration up to the third month. Growth variables reached their asymptotic value after the fourth month of age. An exception was the lens weight which continually increased with age without reaching an asymptotic value. The instantaneous growth rates became less than unity at the third month of age, indi­cating that the maximal percentile growth should be before this stage. The latter was corroborated with the body weight increase and body length curves in which the inflexion point was observed at the 1-month stage. In A. dolores this stage is physiolo­gically associated with puberty and in the present study was reached when the animals achieved 40% of their adult body weight. This study is the basis of an age distribution study of A. dolores with a biological foundation.
20

Recognition of interspecific familiar versus unfamiliar odours among bank voles and yellow-necked mice

51%
Lopucki R., Szymroszczyk P.
Acta Theriologica
|
2003
|
tom 48
|
nr 2
Two experiments (laboratory and field-laboratory) were designed to determine whether individual bank voles Clethrionomys glareolus (Schreber, 1780) and yellow-necked mice Apodemus flavicollis (Melchior, 1834) could distinguish heterospecific odour cues from familiar and unfamiliar individuals. In the laboratory experiment each male bank vole was familiarized for 24 h with odour (cotton wool impregnated with urine and faeces) of male yellow-necked mice and yellow-necked mice were familiarized with odour of male bank voles. In the field-laboratory experiment the individual bank voles and yellow-necked mice captured at the same point were considered familiar and transfered to the laboratory. In laboratory, these individuals were tested in a box (for 5 h) affording them the choice between the odours of familiar and unfamiliar hetero­specific males. Bank voles discriminated between familiar and unfamiliar yellow- -necked mouse odours. Male yellow-necked mice seemed to have a similar ability to recognise odours of familiar bank voles. It is proposed that interactions between these two species occur not only on the species level, but also on the level of individual. This phenomenon (probably asymmetric) can play an important role in spatial orientation, and influence direct contacts between individuals of these species.
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