Ants impact the energy reserves of natural enemies through the shared honeydew exploitation

[EN] Ants, as well as many species of parasitoids and predators, rely on sugar-richfoodssuchashoneydewtofulfilltheirenergeticneeds.Thus,antsandnatural enemies may interact through the shared honeydew exploitation. 2.Ant-exclusionexperimentswereperformedinacitrusorchardtotestthehypothesis that ants may impact the energy reserves of predators and parasitoids through the competitionforhoneydew.Throughtheuseofhigh-performanceliquidchromatography (HPLC)thelevelofantactivitywiththeenergyreservesandfeedinghistoryofindividual specimens collected in the field during representative days of spring, summer, and autumn were related. 3. Out of 145 Aphytis chrysomphali Mercet parasitoids captured in the field, 65% were classified as sugar-fed and 24.7% as honeydew-fed. In summer, when ant activity peaked,therewasasignificant negativecorrelationbetweenthelevelofantactivityand the total sugar content and honeydew feeding incidence by A.chrysomphali. Out of 47 individuals of the predator Chrysoperla carnea sensu lato (Stephens), captured in the field, 55.3% were classified as sugar-fed. We found a significant negative effect of the level of ant activity on the sugar-feeding incidence by C.carneain spring. 4.Thepresentstudyprovidesevidencethatantscaninterferewiththeenergyreserves of natural enemies. This interaction may be widespread in various ecosystems with important consequences for the arthropod community composition and with practical implicationsforbiologicalcontrolgiventhatabsenceofsugarfeedingisdetrimentalfor thefitness of many species of predatorsand parasitoids Dr Jerome Casas is greatly acknowledged for valuable comments on earlier versions of the manuscript and Dr Petr Duelli for providing help with the Chrysoperla identifications. We also thank Dr Cristina Navarro Campos and Dr Aleixandre Beltra for their help in the field samplings and for stimulating discussions, Barbara Rodriguez for help in the laboratory analyses and the reviewers for their helpful comments. This work was supported by the project (RTA2010-00012-C02-02) assigned to F. G. M from the Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA), Spain and the project (BIO2013-48779-C4-1-R) from Spanish Ministry of Science and Innovation and COST action CM1303 on Systems Biocatalysis. Calabuig Gomar, A.; Tena Barreda, A.; Wäkers, FL.; Lucia Fernandez-Arrojo; Plou, FJ.; García Mari, F.; Pekas, A. (2015). Ants impact the energy reserves of natural enemies through the shared honey