Colony characteristics of Vespula germanica (F.) (Hymenoptera, Vespidae) in a Mediterranean climate (southern Australia)

Abstract

Vespula germanica has been accidentally introduced into Australia, where it has now established as a horticultural, agricultural, environmental and nuisance pest. Despite comprehensive and often expensive eradication programs, remarkably little information exists for the species in Australia. Most previous studies were conducted in its native range in England, and in New Zealand where V. germanica has also been introduced. Data on nesting sites in Adelaide were collected over two seasons, with a total of 2640 nests surveyed. The majority of nests (67%) were found below ground, mostly in soil. Twenty-nine percent of nests were found in artificial structures, while the remainder of nests was located above ground. Variation among different habitat types suggests that the species can utilise whatever nest sites are available. Colony duration, timing and seasonal development were also examined by collecting wasp nests over three seasons. Nests were found between November and May. Average mature colonies contained over 9500 small (worker) and 3600 large (queen and male) cells, with some large nests consisting of over 27 500 cells. By the end of May, such colonies have 15 000 wasps emerging from small cells and 2500 wasps emerging from large cells. This is 35-80% more than the numbers of adults produced by V. germanica colonies in England. In addition, in southern Australia a proportion of nests overwinter and survive into the next season, whereas all nests collapse and die out at this time in England. A significant linear relationship was found between wasp traffic and various measures of nest size. These results indicate that in the absence of an adverse climate, V. germanica nests can attain a substantial size. Greater numbers of queens produced in nests may also facilitate a faster rate of population increase in Australia.

Moderate fire severity is best for the diversity of most of the pollinator guilds in Mediterranean pine forests

“…F, D, respectively); Vespula germanica , a eusocial wasp with diverse nesting preferences (Kasper et al. ) and flexible foraging behavior, also thriving in moderate‐severity sites (Appendix : Fig. S6H), possibly because of its ability to colonize various environments successfully (D'adamo and Lozada ); and the sawfly Athalia bicolor , also abundant in moderate‐severity sites (Appendix : Fig.…”

“…Considering the response of some abundant species, we distinguish the ground-nesting generalist bees Halictus resurgens, a very abundant species in moderate-severity sites, and Andrena flavipes (Fig. 3F, D, respectively); Vespula germanica, a eusocial wasp with diverse nesting preferences (Kasper et al 2008) and flexible foraging behavior, also thriving in moderate-severity sites (Appendix S1: Fig. S6H), possibly because of its ability to colonize various environments successfully (D'adamo and Lozada 2009); and the sawfly Athalia bicolor, also abundant in moderate-severity sites (Appendix S1: Fig.…”

High occurrence of colony fusion in a European population of the American termite Reticulitermes flavipes

“…The invasive success of social insects is thought to be, at least partially, attributable to changes in social organization (Chapman and Bourke, 2001;Holway et al, 2002). In Hymenoptera, shifts in the social organization have already been observed, as in the case of the wasp Vespula germanica (Donovan et al, 1992;Kasper et al, 2008) and the bumblebee Bombus terrestris (Buttermore, 1997;Nagamitsu and Yamagishi, 2009). In ants, change in social organization remains highly controversial since the unicolonial in addition to multicolonial organization were described in the native range of several species of ants (Holzer et al, 2006;Pedersen et al, 2006;Fournier et al, 2009;Orivel et al, 2009;Vogel et al, 2009).…”

Larval settlement behaviour in six gregarious ascidians in relation to adult distribution

“…Propagule pressure, defined as the combined effect of the number of individuals introduced and the number of introduction attempts, has been identified as an important predictor of invasiveness of non-native species (Colautti et al 2006). Because conditions for propagule establishment and development often differ between the native and invaded ranges, most invasive species perform differently in localities to which they are introduced, where they are often more abundant (DeWalt et al 2004, Kasper et al 2008, larger (Ross & Auge 2008), comparatively free of predators (Wolfe 2002), less prone to parasitism (Calvo-Ugarteburu & McQuaid 1998) and have a higher reproductive output (Hinz & Schwarzlaender 2004). Moreover, invasive species generally show a strongly aggregated distribution (Kopin et al 2001, Dulloo et al 2002, Campbell & Donlan 2005, Dupont et al 2006 and form large monospecific stands that can monopolise available habitat (Simberloff et al 2005, Rius et al 2009a.…”