2025/03/19 by Charly Géron, Stéphane A. P. Derocles, Hoël Hotte +1 · 1 voice · 1 citation
Agricultural and Biological Sciences · Environmental Science · Biochemistry, Genetics and Molecular Biology · #Plant and animal studies #Ecology and Vegetation Dynamics Studies #Insect and Arachnid Ecology and Behavior
paper · pdf · doi:10.1111/oik.10797
openalex publication_date 2025/03/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/22
Global changes and human activities have increased the likelihood of transport of non‐native insect species all around the globe. When established, the spread of organisms leads to the spatial sorting of the populations, progressively contributing to the selection of individuals with enhanced dispersal performance at the edges of the invaded range. During dispersal, propagules are also subjected to contrasting environmental conditions that can be stressful. These include temperature extremes and variations, desiccation and the quantity and quality of food, which can impose physiological constraints. As a consequence, higher stress tolerance and higher dispersal capacities may be promoted at the range edge. However, only few studies have examined the differences in stress resistance of non‐native insect populations along their invasion gradient. Merizodus soledadinus is a non‐native insect species invading low‐elevation coastal areas of the subantarctic Kerguelen Islands, where its quick spread highly impacts the native fauna. On the Kerguelen Islands, its invasion history is precisely known. This offers a unique opportunity to study its stress resistance in relation to the residence time. In this study, we investigated the effects of the residence time of populations of M. soledadinus on its resistance to heat, desiccation, food deprivation and the combination of these three stresses in the laboratory. We found that desiccation and multiple stress treatments caused the highest mortality rates. Populations close to the range edge showed a longer survival compared to populations with longer residence times. However, the dynamics of survival were different: core populations experienced a steady decline in survival, while range edge populations initially experienced a slow decline in mortality followed by rapid mortality. This suggests greater stress resistance for individuals from populations close to the invasion front, potentially explaining the intense expansion of M. soledadinus on Kerguelen Islands.