Tuesday, December 14, 2010
Terrace Salon Two/Three (Town and Country Hotel and Convention Center)
The German yellowjacket,Vespula germanica (F.) (Hymenoptera: Vespidae), is a highly invasive wasp that exhibits efficient mechanisms while foraging. When foraging on carrion resources, this wasp usually makes repeated visits to the feeding site until depleting the resource. We studied wasps’ learning flights in different conditions. Number of learning flights were recorded in different wasps’ visits and when displacing a food source. Moreover, we analyzed the effect of adding artificial conspicuous cues in wasps learning flights behavior. Wasps were trained to feed from a certain array. At each feeding visit, the studied wasp fed and collected food from the dish, then departed to the nest and returned a few minutes later. Training session consisted on three or four feeding trials (depending on treatment). The numbers of learning flights were registered during wasp departure for all experiments. We found that as more previous experience with food, less were the mean number of learning flights. Furthermore, when food was displaced from the original feeding site, the number of learning flights increased after the following visit. We also found that when feeding in contexts presenting artificial cues, wasps performed less learning flights than in contexts without these references. We conclude that number of learning flights depends on previous wasps ‘experiences with a certain location, as well as on the conspicuity of landmark cues.