Inventory of rodent damage to forests

Abstract

Conversion of coniferous monocultures to more stable mixed stands is one of the crucial tasks of present forestry in the Czech Republic. One of the factors hampering this process is the activity of small rodents that can cause severe damage to young plantations in winter. Little knowledge is still available of the ecology of small mammals in the forest environment and of the factors influencing their distribution and extent of damage. In order to acquire relevant information on rodent impacts on forest regeneration, we mapped the cumulated damage to forest plantations in 13 regions within the Czech Republic in 2007 and 2008. We checked 19,650 trees of eight species on 393 plots. Broadleaves were affected by browsing much more than conifers (20% and 4%, respectively). Of the monitored species, beech was damaged the most frequently (26% individuals). Browsing intensity differed among the regions (6-60% browsed individuals). The least damaged were the plantations at the altitudes below 400 m a.s.l.; on higher located plots the browsing intensity showed no trend. The proportion of damaged trees increased with plantation age up to 6 years, then it did not vary significantly. This study has confirmed that rodents are an important factor with a negative influence on the regeneration of broadleaves. Bark browsing in young trees is affected by several factors and the prediction of damage is complicated. Further research should improve the prediction of the bark browsing threat to young plantations and at the same time the efficiency of protection against rodent-caused damage.

Relationship between rodent density, environmental factors and tree damage caused by rodent species

“…Diff erences in the species spectrum of damaged trees and the extent of damage in various areas of Europe give evidence of a number of diff erent complex factors at play and as such require an assessment of the issue at a regional level and deem any generalization of results unsuitable. While mainly coniferous species are damaged in the boreal zone (Sullivan, Sullivan 2008;Huitu et al 2009), which is related mainly to the given environmental conditions, the area of Central Europe encompasses regionally diff ering spectrums of tree species with various ratios of broadleaved and coniferous species, which is aff ected both by the specifi c natural conditions and silviculture as well (Borowski 2007;Kamler et al 2010Kamler et al , 2011. While for example mainly rowan and beech are damaged in the Czech Republic (Kamler et al 2010), larch and ash are damaged in Poland (Borowski 2007).…”

“…are among such mountain ranges. Apart from two one-off studies (Kamler et al 2011;Suchomel et al 2011), virtually present paper contains the results of a four-year study of damage caused to common beech plantations in the given area.…”

Responses of small mammals to habitat characteristics in Southern Carpathian forests

“…Meantime, they exercise direct and indirect top-down and bottom-up control on the distribution, abundance, and population dynamics of other animal taxa 6 , 7 by being important predators of insects and other invertebrates 8 and food resources for many vertebrate predators. On the other hand, seed predation and consumption of tree bark by rodents can have negative effects on forests, with young trees being especially affected 9 , thus potentially hindering forest regeneration 10 .…”

Diversity of small mammals synusias of the open forest sites of the Beskydy and Jeseníky Mts.

“…Apart from a single environmental study of sites affected by air pollution (Nesvadbová, Gaisler 2000), only faunisic data on the occurrence of individual small mammal species are available from the Jeseníky Mts Beneš 2001, 2002;Anděra 2000Anděra , 2011 as well as a one-off monitoring of browsing damage to trees summarized by Kamler et al (2010Kamler et al ( , 2011. Preliminary evaluations of habitat preferences of selected small mammal species in a nonforest environment (Suchomel et al 2009) and the impact of voles (Arvicolinae) on beech (Fagus sylvatica) plantations were conducted in the area only recently.…”