The German wasp,
Vespula germanica, is a vespid wasp native to Europe, Northern Africa and temperate Asia, that have recently invaded much of the new world (North America and South America), Australia and New Zealand, where they pose a significant pest to indigenous fauna. These wasps are still spreading, for example, along the western coast of the United States where they arrived in about 1980 and into Patagonia in 1990; in these new areas they are far more destructive to the environment than in regions where they are well established. German wasps are aggressive hunters of insects, which they masticate and feed to their larvae, and require large amounts of protein to feed their brood. The adults themselves eat pollen, nectar, other carbohydrates and secretions produced by their young. Although
V. germanica can play a positive role in diminishing numbers of pest insects, this wasp also out-competes native species for food resources as well as directly killing native species to extinction, especially in recently invaded habitats.
Vespula germanica also has a large negative impact on human activities such as bee-keeping, cattle rearing, and fruit orchards. German wasps look very similar to the closely related common wasp (
Vespula vulgaris), but have a different coloration pattern on their face and back. These wasps and others of the genera
Vespula and
Dolichovespula are known in the United States as yellowjackets. Like other yellowjackets, German wasps build their paper nests in crevices near to or on the ground (as opposed to hornets, which hang their nests in places six feet or higher). A colony consists of a queen and up to several thousand sterile workers when the nest is fully mature. In the fall the queen stops laying worker eggs, and lays queen eggs and male (drone) eggs and the nest begins to decline. The new queens mate (with drones from other nests) and then only the queens overwinter, to form a new nest the following spring. In mild winters of New Zealand about 10% of German wasp nests do not die over the winter, and these nests become very large and troublesome. Methods of toxic bait traps, using synthetic pheromones and natural food attractants, are important and effective for local and temporary reduction of populations, however more permanent methods for eliminating colonies are more difficult. (
CABI, 2011;
Reierson et al. 2009; Sackmann et al. 2001;
Wikipedia 2011)
