IN CLASS/OUTSIDE: In classroom
CLASS: Senior (5th and 6th)
HERITAGE SUBJECT: Science
CURRICULUM STRANDS: Living things (Science)
The wasp is a much maligned insect. It actually does not spend its time going round looking for humans to sting! The life cycle of the wasp actually plays a very important role in our natural environment. Wasps are native social insects.
This means that there is a queen and a colony of workers that live together in a nest. The queen hibernates for winter and in March wakes up. She emerges, chooses a nest site and begins to build a paperlike nest from chewed up timber. This nest can be in a hedge, in an attic or roof space, or in a disused shed. She lays eight eggs and when these grow into worker wasps they take over the running of the nest. The queen goes into egg production full time and the workers build six-sided cells for the eggs. The workers are all female and they feed the baby wasps with chewed up greenflies, aphids and other insect garden pests. The adult wasps, on the other hand, feed on a sweet-tasting substance excreted by the grubs in the nest.
So all summer long from April to August, wasps do a great deal of good, keeping down the numbers of harmful plant pests. By the end of August the queen will have laid up to 40,000 eggs and is beginning to tire. The nest can be the size of a football by now. The workers build different shaped cells in which eggs are laid that go on to be queens, while different shaped cells again cause her to lay eggs that produce drones.
These all leave the nest when mature, mate with those from other nests and the newly fertilized queens go into hibernation at once and emerge to start the cycle all over again next March. The old queen back at the original nest lays a last round of eggs and dies by the end of August. This last round of worker wasps have no younger babies to feed with insects, nor indeed any grubs to lick sweettasting liquid from. It is these last wasps during the months of September and October, for the six weeks lifespan that they have, that have to hunt everywhere for sweet food. They can eat nectar from flowers, or suck the juices of fallen apples and blackberries. But many of them do come into our homes seeking sugar there.
Of course they will sting if assaulted by an angry or terrified human. But they don’t seek us out deliberately to sting us. By the end of October they will all have died. The nest is empty and won’t be used by next year’s queen. The whole cycle will begin again the following March.
About their sting — the sting of a wasp is like a needle and can be withdrawn after it is used in order to sting again. The bee has a sting with a serrated edge which gets stuck in our thick skin and cannot be withdrawn so a bee is torn apart as it tries to withdraw it from a human and will later die.
Things to do:
- Get hold of a disused, empty wasps’ nest. Spray it with hair spray to render it less brittle. Bring into school and let the class examine the nest in detail. It can be cut in half in due course so that the intricate cell structure can be appreciated.