Do shrews have an impact on soil invertebrates in Eurasian forests?

:Abundance and food consumption of shrews in the European part of the southern taiga (Valdai district, Russia) were investigated. Average population densities of these animals were estimated 31/ha in dry boreal spruce forest, 179 in boreal Picea abies – Oxalis acetosella forest, and 224–258 in rich spruce forest. Food consumption in those habitats was estimated at 25 kg/ha, 152 kg/ha, and 212–244 kg/ha per year, respectively. These data are similar to those for western Siberian taiga (132–264 kg/ha), mixed forest in the Russian Far-East (177–351 kg/ha), and larch forests in north-east Siberia (265–330 kg/ha). These figures also correspond with the biomass of soil invertebrates in the above ecosystems. This provides evidence that shrews have a significant impact on litter decay processes. In particular, shrews diminish the population density of soil invertebrates thus increasing their productivity. Such a response to harvesting is well-known for many populations, from microorganisms to ungulates. Red-toothed shrews do not significantly change the density of soil invertebrates during summer periods, but they probably accelerate decomposition of forest litter and organic matter in the upper soil layers.