Forest clearing and sex ratio in forest-dwelling wood ant Formica aquilonia

Abstract

Sex ratios of ants have been shown to vary with food resource levels in several studies, but it is not known whether forest clear-cutting has any effect on sex ratio of aphid-tending forest-dwelling ants. We investigated whether the offspring sex ratio of the forest dwelling ant Formica aquilonia varied as a response to clear-cutting. We found that the proportion of males was smaller in clear-cuts than in adjacent forests. Our results are among the first showing that anthropogenic changes in forest structures may have a potential to modify sex ratios of social insects and other forest-dwelling animals.

Similarity of Body Size in Queens of the Wood antFormica aquiloniafrom Optimal and Sub-Optimal Habitats Indicates a Strong Heritable Component

“…It is a highly polygynous (multiple queens) and polydomous (multiple nests) species, with large nest mounds containing over a million workers and hundreds of queens (Pamilo 1982; Rosengren et al 1987). F. aquilonia has ecological effects over several trophic levels and is threatened by commercial forest clear-cutting, which reduces the production of sexual offspring, nest survival, and food resources (Sorvari and Hakkarainen 2005, 2007a, 2009) and creates a bias upon the sex ratio of sexual offspring (Sorvari and Hakkarainen 2007b). …”

Stand type is more important than red wood ant abundance for the structure of ground‐dwelling arthropod assemblages in managed boreal forests

“…Disturbances in boreal forests, such as fire or logging, can affect the size and vitality of ant colonies and cause changes in community interactions (Vepsäläinen & Wuorenrinne, 1978; Rosengren et al , 1979; Gösswald, 1985; Sorvari & Hakkarainen, 2004, 2005, 2007a, b). For example, wood ants often abandon their nest mounds within a few years of clear cutting (Sorvari & Hakkarainen, 2005, 2007a), but the numbers of active bud‐mounds increase with forest succession, at least until canopy closure (Punttila, 1996; Sorvari & Hakkarainen, 2007a).…”

Survival of transplanted nests of the red wood antFormica aquilonia(Hymenoptera: Formicidae): The effects of intraspecific competition and forest clear‐cutting

“…In the course of translocation, large amount of workers were possibly lost in unfamiliar environment resulting in relative small nest compared to the large amount of material and ants transferred. Quick growth of nest is important because as a polygynous red wood ant species, the queens of F. aquilonia are likely short‐lived (Keller & Genoud, ), and small nests do not produce new reproductive individuals; especially queens are mostly produced in large nests (Sorvari & Hakkarainen, , ).…”

“…In the course of translocation, large amount of workers were possibly lost in unfamiliar environment resulting in relative small nest compared to the large amount of material and ants transferred. Quick growth of nest is important because as a polygynous red wood ant species, the queens of F. aquilonia are likely short-lived (Keller & Genoud, 1997), and small nests do not produce new reproductive individuals; especially queens are mostly produced in large nests (Sorvari & Hakkarainen, 2005, 2007b. Table A1 The survival of transplanted nests, the levels of intraspecific competition (sum of the basal areas [m 2 ] of nests of native Formica aquilonia), and clear-cutting (visually estimated percentage of clear-cut area) within a radius of 50 m from the transplanted nest.…”