Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


abundance

Proposals for improving a non-invasive method for estimating abundance of mouse-like rodents and shrews in urban areas

Previously we proposed a new reconnaissance method for estimating the total abundance of small mammals in urban areas. The method includes placing plastic bottles with bait inside equal distances apart. In this research we examined two ways to improve the method: using bottles of smaller volume (0,25 liters instead of 0,5 liters) to increase the ergonomics and using opaque bottles to make them more attractive for animals. Bigger and smaller bottles with neck diameter of 38 mm were fastened in pairs which were set in a transect with a fi ve-meter spacing.

Ecological Aspects of the Distribution and Abundance Dynamics of Woodpecker (Dendro­ copos) in the Northern Lower-Volga Region

On the basis of our 1996-2009 field surveys in the Saratov region and adjacent territories, and our analysis of the literature data, the distribution and abundance dynamics of Dendrocopos major, D. syriacus, D. medius, D. leucotos, and D. minor is considered. The present habitation of D. leucotos in the Saratov region has been established to be associated with ripe deciduous woods in the Saratov Right-Volga-bank region; the bird penetrates for nesting up to 51°40* lati­ tude North along the Khopyor and Medveditsa river valleys. D.

Dynamics of the Number and Current State of Population Red-footed Falcon (Falco Vespertinus Linnaeus, 1766) in the North of the Lower Volga Region

The abundance dynamics of Falco vespertinus is considered on the basis of our field surveys carried out within the Saratov region and adjacent territories in 2011–2016 and analysis of the literature data. It is shown that F. vespertinus is now presented by stable populations in the spacious territory of the Trans-Volga part of the region. However, some reduction of its abundance was registered here for the last several decades of the 20th century. Currently, the falcon populations in the Volga right-bank region can be characterized as mosaic, and the F.

Taxonomic Composition of Ground Invertebrates and Their Ratio in Different Types of Deciduous Forests within Tobolsk District of Tyumen Region

The composition and spatial distribution of the surface & litterdwelling mesofauna in leaved forests the indigenous terrace of the Irtysh river are analyzed on the basis materials of accounting for invertebrates by soil traps. The surveys were carried out in 2005–2010 in three types of forests – aspen forest, lime forest and birch forest, located within Tobolsk district of the Tyumen region (southern taiga, Western Siberia).