Starvation resistance and effects of diet on energy reserves in a predatory ground beetle (Merizodus soledadinus; Carabidae) invading the Kerguelen Islands

• Published in: Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology
• Main Authors: Laparie, Mathieu, Larvor, Vanessa, Frenot, Yves, Renault, David
• Other Authors: Ecosystèmes, biodiversité, évolution Rennes (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Programme 136 IPEV, ANR-07-VULN-0004,EVINCE,Vulnerability of native communities to invasive insects and climate change in sub-antarctic islands.(2007)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: Invasive insect; Glucose; Metabolic stores; Prey selection; Sub-Antarctic island; Trehalose; Triglyceride; Trophic stress; envir; geo; Antarctic; Kerguelen; Kerguelen Islands; Antarc*
• Online Access: https://doi.org/10.1016/j.cbpa.2011.09.011; https://hal.archives-ouvertes.fr/hal-00677499

International audience The relationship between nutritional requirements and the availability or quality of food is a prime parameter in determining the geographical expansion of invasive insects. At the sub-Antarctic Kerguelen Islands, the invasive ground beetle Merizodus soledadinus becomes the main invertebrate predator when it colonizes new habitats, leading to the local extinction of native fly species. Such changes in the structure of prey communities may alter the energy management (storage and expenditure) of this predator. In this species, we monitored survival and bodymass during food deprivation, in addition to evaluating the effects of two distinct diets (maggots versus enchytraeids) on the consumption and restoration of body reserves (sugars and triglycerides). We found that adults can starve formore than 60 days, and feed every 3.76 days on average when food is available. We recorded higher predation rates on maggots, associated with steeper body mass variations, compared to enchytraeids. Sugars and triglycerides were significantly consumed during food deprivation and restored after refeeding, but varied similarly among individuals supplied on the distinct diets. Other parameters may determine the food preferences observed, such as salt content in prey tissues, because M. soledadinus mainly feeds in hypersaline foreshore habitats, and may limit the consumption of osmotic conformers.