Thermal adaptation affects interactions between a range‐expanding and a native odonate species

Abstract

Summary 1. Increasing temperature and invading species may interact in their effects on communities. In this study, we investigated how rising temperatures alter larval interactions between a naturally range‐expanding dragonfly, Crocothemis erythraea, and a native northern European species, Leucorrhinia dubia. Initial studies revealed that C. erythraea grow up to 3.5 times faster than L. dubia at temperatures above 16 °C. As a result, we hypothesised that divergent temperature responses would lead to rapid size differences between coexisting larvae and, consequently, to asymmetric intraguild predation at higher ambient temperatures. 2. Mortality and growth rates were measured in interaction treatments (with both species present) and non‐interaction controls (one species present) at four different temperature regimes: at an ambient temperature representative of central Germany, where both species overlap in distribution, and at temperatures increased by 2, 4 and 6 °C. 3. The mortality of C. erythraea did not differ between treatment and control. In contrast, mortality of L. dubia remained similar over all temperatures in the controls, but increased with temperature in the presence of the other species and was significantly higher there than in the controls. We concluded that L. dubia suffered asymmetric intraguild predation, particularly at increased temperature. Reduced growth rate of L. dubia in the interaction treatment at higher temperatures also suggested asymmetric competition for prey in the first phase of the experiment. 4. The results imply that the range expansion of C. erythraea may cause reduction in population size of syntopic L. dubia when temperature rises by more than 2 °C. The consequences for future range patterns, as well as other factors that may influence the interaction in nature, are discussed.

Testing for taxonomic bias in the future diversity of Australian Odonata

“…For example, aside from the Bass Strait, there are several gaps along the Great Dividing Range that suggest odonate species diverged according to breaks in the terrain (Watson & Theischinger, ). Even if species can disperse to climatically suitable regions, it may not ensure successful establishment (Angert et al ., ), resident species could competitively exclude new arrivals or alternatively, climate change may provide immigrant species with a competitive advantage, displacing resident species (Suhling & Suhling, ). However, research in Victoria has shown the relationship between local and regional richness of macroinvertebrates appears to be linear, suggesting communities are not necessarily saturated, and could accept immigrant species (Marchant et al ., ).…”

Effects of experimental warming on survival, phenology, and morphology of an aquatic insect (Odonata)

“…In other invertebrates, warming to temperatures below the ULL have been associated with increased mortality (Folt et al ., ; Flenner et al ., ; Shama et al ., ; Pelini et al ., ), and temperature can exacerbate the effects of other stressors (Folt et al ., ; Schisler et al ., ; Verberk & Calosi, ) and decrease immune responses even when enhancing other aspects of performance (Karl et al ., ). The presence of an intra‐guild predator can increase mortality with warming in some but not all species of odonates (Suhling & Suhling, ). For species that diapause in the larval stage, warming may prevent them from entering this diapause stage and may elevate metabolic costs and increase mortality (Hassall & Thompson, ).…”

Simulated climate change increases larval mortality, alters phenology, and affects flight morphology of a dragonfly

“…). However, within odonates, species responses to environmental change can be highly variable and depend on both the context of the warming and the presence of additional stressors (e.g., competitors, potential intraguild predators, food limitation), and on the specific responses quantified (e.g., growth rate, mortality, size at or timing of emergence; Suhling and Suhling , Nilsson‐Örtman et al. , Suhling et al.…”