Vespula germanica

Colonies of V. germanica share many characteristics with those of V. vulgaris (common wasp) and V. pensylvanica (western yellowjacket), so they are very often studied together.

To help with identification, a good practice to observe is to first categorize the wasp as worker, queen, or male before identifying it as V. vulgaris or V. germanica.

Gastral pattern (the black dots or marks on the abdomen) are highly variable and not good characteristics to use in identifying.

However, the identification of a wasp as V. vulgaris may be difficult because the normally unbroken black mark on its clypeus can sometimes appear broken (particularly in males) making it look extremely similar to V. germanica.

[citation needed] V. germanica originated in Europe, Asia, and North Africa and can now be found in sections of every continent but Antarctica.

These wasps are polyphagous predators which feed on native arthropods, and because they are able to outdo many other animals for food, they have caused considerable harm to the indigenous wildlife of areas which they have invaded.

[5] High variation in the sequence and diversity of tasks performed by V. germanica workers suggests limited temporal polyethism exists within the species.

The schedule of temporal polyethism found in V. germanica is highly accelerated when compared to other Hymenoptera, which is likely related to worker lifespan.

[9] It is believed that the flexibility in V. germanica's foraging behavior is a key factor in their ability to rapidly colonize new areas in a variety of ecological environments.

As scavengers, V. germanica are forced to make numerous trips between the location of the food source and the nest, where the larvae are kept and fed.

The ability to relocate previously discovered food sources is only one example of the diverse cognitive mechanisms at play within V. germanica's behaviors.

In addition, V. germanica wasps have been shown to have sensorimotor learning capacities which allow them to associate visual stimuli with certain motor responses.

Its flexibility in nesting and diet habits in conjunction with its foraging capabilities may help explain the success with which V. germanica has invaded so many different ecological areas.

This contradicts the theory that the reproductive skew seen in V. germanica is part of an evolutionary strategy of males due to asymmetries in relatedness.

In the past, V. germanica was thought to be an exception to the general pattern that high mating frequency led to low levels of worker reproduction.

They are known to eat carrion, live arthropods (including spiders[12]), fruit,[10] honeydew, and processed human food and garbage.

[9] For example, many Vespula species have been observed feeding on dead honey bees (Apis mellifera) found outside the beehive entrance in the late summer.

[18] Wasp numbers reach their greatest densities in beech forest of the South Island, due to the abundant honeydew produced by the beech-scale insect there.

However, German wasps were quickly succeeded in much of the South Island and its beech forests by Vespula vulgaris accidentally introduced in the 1970s.

German wasp rasping wood with which to build its nest
Macrophotography of queen of V. germanica in hibernation, awaiting spring to establish a new insect colony
Queen V. germanica and male mating
Vespula germanica nest (illustration by Des Helmore )
Workers at the nest entrance