Insects in a warmer world: ecological, physiological and life‐history responses of true bugs (Heteroptera) to climate change

Abstract

Focusing on the southern green stink bug, Nezara viridula (Pentatomidae), in central Japan the effects of climate change on true bugs (Insecta: Heteroptera) are reviewed. In the early 1960s, the northern edge of the species's distribution was in Wakayama Prefecture (34.11N) and distribution was limited by the 15 1C coldest month (January) mean temperature isothermal line. By 2000, N. viridula was recorded 70 km further north (in Osaka, 34.71N). Historical climate data were used to reveal possible causes of the northward range expansion. The increase of mean and lowest winter month temperatures by 1-2 1C in Osaka from the 1950s to the 1990s improved potential overwintering conditions for N. viridula. This promoted northward range expansion of the species. In Osaka, adult diapause in N. viridula is induced after mid-September, much later than in other local seed-feeding heteropterans. This late diapause induction results in late-season ineffective reproduction: some females start oviposition in autumn when the progeny have no chance of attaining adulthood and surviving winter. Both reproductive adults and the progeny die. A period from mid-September to early November represents a phenological mismatch: diapause is not yet induced in all adults, but it is already too late to start reproduction. Females that do not start reproduction but enter diapause in September have reduced postdiapause reproductive performance: they live for a shorter period, have a shorter period of oviposition and produce fewer eggs in smaller egg masses compared with females that emerge and enter diapause later in autumn. To some extent, N. viridula remains maladapted to Osaka environmental conditions. Ecological perspectives on establishment in recently colonized areas are discussed. A review of available data suggests that terrestrial and aquatic Heteroptera species respond to climate change by shifting their distribution ranges, changing abundance, phenology, voltinism, physiology, behaviour, and community structure. Expected responses of Heteroptera to further climate warming are discussed under scenarios of slight (o2 1C) and substantial (42 1C) temperature increase.When our grandchildren write the history of global warming -how we discovered and debated it, and what we finally did about it -the stinkbugs . . . may not loom large . . . But our descendants may well decide that it was the long string of such close-to-home observations -the early springs, the shifting ranges of plants and animals, the mortal heat waves -that, more than any climatological data, convinced people that something needed to be done about global warming.R. Kunzig (2005)

Alien species in a warmer world: risks and opportunities

“…The southern green stink bug Nezara viridula, formerly a sub-tropical species, has been expanding its range northward in temperate regions of Japan and Europe since the 1960s, probably because of reduced mortality resulting from milder winters. In the newly invaded regions in Japan, it has become a major pest and out-competes the indigenous Nezara antennata [38]. Similarly, the main invasion of the buffelgrass Pennisetum ciliare into the Lower Sonoran Desert of southern Arizona coincided with warmer winters since the 1980s.…”

Physiological tolerances account for range limits and abundance structure in an invasive slug

“…Even where much of the evidence has been provided (e.g. Hill & Hodkinson 1992;Crozier 2004;Bird & Hodkinson 2005;Battisti et al 2006;Crozier & Dwyer 2006;Musolin 2007), often the focus remains on one part of the species range margin despite the importance of understanding patterns and processes across the species range (Gaston 2003;Franco et al 2006;Thomas et al 2006;Merrill et al 2008).…”

Anisops sardeus (Heteroptera): A new expansive species in Central Europe

“…A recent review (Musolin 2007) suggests that terrestrial and aquatic Heteroptera species respond to climate change by shifting their distributional ranges, changing abundance, phenology, voltinism, physiology, behaviour, and community structure. Depending on climate scenario, global average surface temperature is predicted to increase in likely ranges from 1.1 to 6.4 • C during the 21 st century (IPCC 2007).…”