Analysis of the Spatial Distribution of Settlements of Red Wood Ants in the Baikal Region

Abstract

Outbreaks of defoliating insects constantly emerge and spread in the heavily forested Baikal region. Biological control is the approach of choice in pest management, and red wood ants are used to control defoliating insects at their outbreak sites. The purpose of the present paper is to choose the forest plots with complexes of red wood ant nests in the Baikal region and to estimate the level of protection of these plots from defoliating insects using hybrid geoinformation system (GIS). The Institute for System Dynamics and Control Theory SB RAS geoportal (http://geos.icc.ru) is the hybrid GIS. During fieldwork, 101 nests of F. aquilonia Yarr. and 20 nests of F. lugubris Zett. were found. One hundred and two nests (88 F. aquilonia nests and 14 F. lugubris nests) formed nest complexes and were located on 18 forest plots. Two parameters were used to estimate protection level of forest plots from defoliating insects: the average number of nests per 1 hectare (settlement density) and the total area of dome bases of all anthills located on 1 hectare (power of the nest complex). The research revealed that only four forest plots (“Uzury”, “Khalgay”, “Onguren_2”, and “Onguren_3”), situated in the mountain taiga pine landscape, were protected from defoliating insects (settlement density ≥5 nests/ha and power of nest complex >6 m2/ha). Besides, the complex of nests in the “Onguren_2” forest plot can be a source for capture of filial nests. The “Arshan_2” forest plot, situated in the mountain taiga dark coniferous landscape of reduced development, had the lowest density of settlements of ants (less than two nests per hectare). The state-of-the-art hybrid GIS is a tool that can be used to quickly and efficiently discover and analyze the spatial distribution of settlements of red wood ants