Responses of small mammals to clear-cutting in temperate and boreal forests of Europe: a meta-analysis and review

We analyzed the responses of small mammals to clear-cutting in temperate and boreal forests in Europe. We conducted a meta-analysis of published research on most often studied small mammal species (the striped field mouse, the yellow-necked mouse, the wood mouse, the field vole, the common vole, the bank vole, the Eurasian harvest mouse, the common shrew and the Eurasian pygmy shrew), comparing their abundance on clear-cuts and in unharvested stands. For four other species (the gray-sided vole, the Siberian flying squirrel, the Eurasian red squirrel and the hazel dormouse), we provide a qualitative review of their responses to forest harvest. Results of the meta-analysis suggest that common species of small mammals usually increase in abundance after clear-cutting or are unaffected by this disturbance. As an exception, the yellow-necked mouse declines after clear-cutting in boreal but not in temperate forest. The qualitative review suggests that the responses of more specialized (e.g., arboreal) species to forest harvest are more varied than the responses of generalist species included in the meta-analysis. For some species of small mammals (e.g., the Siberian flying squirrel), habitat loss resulting from forest harvest is a major threat.MNiSW Grant NN30439153

Interspecific aggression and behavioural domination among four sympatric species of shrews

Level of interspecific aggressiveness should reflect intensity of interference competition, and large-dominant and small-subordinate species should evolve aggressive and passive agonistic behaviours, respectively, to achieve stable co-existence. We tested these ideas investigating interspecific behavioural dominance in a four-species community of shrews differing in body size (Sorex minutus Linnaeus, 1766; Sorex araneus Linnaeus, 1758; Neomys anomalus Cabrera, 1907; Neomys fodiens (Pennant, 1771)), by placing interspecific pairs in a neutral field. The order of dominance (determined on the basis of duration of offensive and defensive behaviours, total time spent in the shelter, and ‘final shelter resident’ index) corresponded to the order of body size: N. fodiens > N. anomalus > S. araneus > S. minutus. The highest number of conflicts and least pronounced dominance of N. anomalus over S. araneus suggest the strongest interference competition between these species. The different social organization of N. anomalus (tolerant and gregarious versus intolerant and solitary in the other three species) did not decrease its aggressiveness and dominance rank. The larger Neomys species were more aggressive and initiated relatively more offensive behaviours, whereas the smaller Sorex species initiated more defensive behaviours. The presence of food and shelter did not intensify conflicts. Nevertheless, dominating species restricted the access of subordinate species to the shelter

Interspecific aggression and behavioural domination among four sympatric species of shrews

Level of interspecific aggressiveness should reflect intensity of interference competition, and large-dominant and small-subordinate species should evolve aggressive and passive agonistic behaviours, respectively, to achieve stable co-existence. We tested these ideas investigating interspecific behavioural dominance in a four-species community of shrews differing in body size (Sorex minutus Linnaeus, 1766; Sorex araneus Linnaeus, 1758; Neomys anomalus Cabrera, 1907; Neomys fodiens (Pennant, 1771)), by placing interspecific pairs in a neutral field. The order of dominance (determined on the basis of duration of offensive and defensive behaviours, total time spent in the shelter, and ‘final shelter resident’ index) corresponded to the order of body size: N. fodiens > N. anomalus > S. araneus > S. minutus. The highest number of conflicts and least pronounced dominance of N. anomalus over S. araneus suggest the strongest interference competition between these species. The different social organization of N. anomalus (tolerant and gregarious versus intolerant and solitary in the other three species) did not decrease its aggressiveness and dominance rank. The larger Neomys species were more aggressive and initiated relatively more offensive behaviours, whereas the smaller Sorex species initiated more defensive behaviours. The presence of food and shelter did not intensify conflicts. Nevertheless, dominating species restricted the access of subordinate species to the shelter

Responses of small mammals to clear-cutting in temperate and boreal forests of Europe: a meta-analysis and review

We analyzed the responses of small mammals to clear-cutting in temperate and boreal forests in Europe. We conducted a meta-analysis of published research on most often studied small mammal species (the striped field mouse, the yellow-necked mouse, the wood mouse, the field vole, the common vole, the bank vole, the Eurasian harvest mouse, the common shrew and the Eurasian pygmy shrew), comparing their abundance on clear-cuts and in unharvested stands. For four other species (the gray-sided vole, the Siberian flying squirrel, the Eurasian red squirrel and the hazel dormouse), we provide a qualitative review of their responses to forest harvest. Results of the meta-analysis suggest that common species of small mammals usually increase in abundance after clear-cutting or are unaffected by this disturbance. As an exception, the yellow-necked mouse declines after clear-cutting in boreal but not in temperate forest. The qualitative review suggests that the responses of more specialized (e.g., arboreal) species to forest harvest are more varied than the responses of generalist species included in the meta-analysis. For some species of small mammals (e.g., the Siberian flying squirrel), habitat loss resulting from forest harvest is a major threat.MNiSW Grant NN30439153

Mast seeding promotes evolution of scatter-hoarding

Many plant species worldwide are dispersed by scatter-hoarding granivores: animals that hide seeds in numerous, small caches for future consumption. Yet, the evolution of scatter-hoarding is difficult to explain because undefended caches are at high risk of pilferage. Previous models have attempted to solve this problem by giving cache owners large advantages in cache recovery, by kin selection, or by introducing reciprocal pilferage of 'shared' seed resources. However, the role of environmental variability has been so far overlooked in this context. One important form of such variability is masting, which is displayed by many plant species dispersed by scatterhoarders. We use a mathematical model to investigate the influence of masting on the evolution of scatter-hoarding. The model accounts for periodically varying annual seed fall, caching and pilfering behaviour, and the demography of scatterhoarders. The parameter values are based mostly on research on European beech (Fagus sylvatica) and yellow-necked mice (Apodemus flavicollis). Starvation of scatterhoarders between mast years decreases the population density that enters masting events, which leads to reduced seed pilferage. Satiation of scatterhoarders during mast events lowers the reproductive cost of caching (i.e. the cost of caching for the future rather than using seeds for current reproduction). These reductions promote the evolution of scatter-hoarding behaviour especially when interannual variation in seed fall and the period between masting events are large. This article is part of the theme issue 'The ecology and evolution of synchronized seed production in plants'

Data from: Effects of nitrogen deposition on reproduction in a masting tree: benefits of higher seed production are trumped by negative biotic interactions

Relatively little is known about the effects of anthropogenic environmental changes on reproductive ecology of trees. Yet, recruitment is a primary determinant of the long-term dynamics of plant populations in changing environments. We used the Long-Term Ecological Research site at Harvard Forest to evaluate the effects of chronic (over 25 years) nitrogen fertilization on reproductive ecology of red oaks (Quercus rubra). Oaks growing in fertilized plots produced 4–9 times more acorns than control trees. However, nitrogen deposition simultaneously affected oaks’ biotic interactions. It increased pre-dispersal seed predation by insects (primarily weevils, Curculio spp.) on fertilized plots, most likely as the result of the disruption of predator satiation. In addition, infestation by weevils was more likely to result in embryo destruction in fertilized than in control acorns. Furthermore, the proportion of acorns dispersed and cached by rodents decreased on fertilized plots. Finally, germination of fertilized acorns was lower than control acorns, even after controlling for the effects of weevils and rodents. Inclusion of the altered biotic interactions reversed the final picture of the effects of long-term nitrogen fertilization on oak reproduction: the positive effects on acorn quantity were trumped by the nitrogen-mediated changes in biotic interactions. Synthesis. Our results stress the importance of considering indirect effects and consumer interactions when evaluating the effects of environmental change on plant population dynamics. Long-term nitrogen fertilization has a strong potential to decrease the recruitment of masting trees. Given the ubiquitous increase in the anthropogenic nitrogen deposition, processes similar to those found in our system might operate in others, resulting in a widespread alteration in trees’ recruitment dynamics

Negative effects of density on space use of small mammals differ with the phase of the masting‐induced population cycle

Home range size generally decreases with increasing population density, but testing how this relationship is influenced by other factors (e.g., food availability, kin structure) is a difficult task. We used spatially explicit capture–recapture models to examine how home range size varies with population density in the yellow‐necked mouse (Apodemus flavicollis). The relationship between population density and home range size was studied at two distinct phases of population fluctuations induced by beech (Fagus sylvatica) masting: post‐mast peak in abundance (first summer after mast, n = 2) and subsequent crash (second summer after mast, n = 2). We live‐trapped mice from June to September to avoid the confounding effects of autumn seedfall on home range size. In accordance with general predictions, we found that home range size was negatively associated with population density. However, after controlling for the effect of density, home ranges of mice were larger in post‐mast years than during the crash phase. This indicates a higher spatial overlap among neighbors in post‐mast years. We suggest that the increased spatial overlap is caused by negative density‐dependent dispersal that leads to high relatedness of individuals within population in the peak phase of the cycle