Signals its Toxicity

Wasps belong to the order hymenoptera as do bees and ants. There are about 5,000 wasps species, of which 50 have been found in Sweden. Characteristically wasps fold their wings lengthwise along their body when resting. In flight, the front wings and rear wings attach to one another with hooks to form a strong broad flight wing.

Appearance and characteristics

There are both social and solitary wasps. A solitary wasp female searches for or builds individual secluded fry cells and lays an egg in each cell. She then adds a suitable number of paralyzed prey animals as food to the larva and plugs the cell. The larvae winter in their breeding cells and emerge first in the spring.


Among the social wasps, only young queens are wintering. All the rest of the community die before winter. In the spring, the queen builds a small nest of chewed wood which she mix with saliva into a malleable pulp that turns into paper when dried. She lays eggs in fry cells and feeds the larvae until their adult stage. She then devotes herself completely to laying eggs and lets her sterile daughters take over the feeding of the larvae and the building of the nest, which advances very quickly. The nest does not have to be particularly strong as it only has to last one season. For each egg she lays, the queen can choose to fertilize or not fertilize it with stored sperm from last year's mating during the swarming. Fertilized eggs become females. Unfertilized eggs develop into males.

Feeding and catching

The wasp has warning colouration - black and yellow stripes. It is important for it to clearly signal its toxicity so that it is not caught by for example a bird and get wounded. Young birds quickly learn to avoid wasps after being stung in the tongue or throat. Some non-venomous insects, such as many species of hoverfly and the wasp beetle, mimic the warning colouration of wasps and bees to deter insect eaters. Female wasps have a stinger which is a modified egg laying tube. The stinger is in contact with a venomous bladder and does not have barbs like the bee's stinger, so the wasp can sting repeatedly.

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