Wasps

Wasps

Appearance
Wasps are approximately 15 to 25 mm long and have the famous black and yellow stripes.

Life Cycle
All Wasps in the UK follow the same life cycle.  Wasps like most insects go through 4 stages of ‘development’ (complete metamorphosis).

Egg – larvae – pupae – adult
The ‘Queen’ wasps hibernate over the winter to emerge in spring.  Depending on the species, the queens choose a suitable site to start the ‘new’ wasp nest.  OLD wasp nests from previous years are not used again although it has been known for the queen to start her new nest adjacent to or ‘within’ an old wasp nest (vespula vulgaris).

In addition, it is possible for several queens who survived the winter (normally all from the same previous years wasp nest) to start ‘construction’ of their new wasp nest’s in close proximity to each other.

The queens start off by ‘collecting’ wood, which they then ‘chew’ up with their saliva to make a kind of paper maché or wood pulp to begin forming a nest.

When the queen’s first offspring emerge from pupation as adult wasps, they are all known as ‘workers’ in the colony and are all sterile females.  The queen wasp continues to lay more egg’s and the workers take over the responsibility of nest building, catching insects which they kill with their sting to take back to the nest to feed to the young ‘grubs’ (larvae.

The workers chew up the insects and again ‘masticate’ the food with their saliva to feed to the grubs.  In return, the grubs secrete a sugary substance, which feeds the workers.

Over the following weeks and months the wasp colony grows and grows.  The queen barely gets out these days as she is continually laying egg’s and the workers are now a formidable force as the population rapidly grows in size.

At its peak in the summer, an average wasp colony of common wasps (vespula vulgaris) may contain up to 20,000 individuals.  It’s worth noting, that heat is a major contributor to the rapid development of the wasp nest.  Queens who selected their nest site in a warm location achieve ‘big results’.  Also the availability of quality food is an important deciding factor.

At the end of the summer, the wasp colony takes on a different function.  The queen now starts to lay ‘different’ eggs.  These will eventually emerge as males (drones) and new young queens.  The activity becomes ‘very active’ and the workers are super protective about their nest.

The young queens mate with several drones to become fertilized for the following year.

Eventually the whole colony dies off apart from the new queens who like the queens before them, find a suitable place to hibernate for the winter.

Diet
A wasps diet consists of a number of insects and fruits.  They are also carnivores.

How to spot a wasp nest
Nests are frequently located in loft spaces, cavity walls, tree stumps/flower beds and behind structural cladding.

Look in the general direction of the wasp’s flight path and see where it takes you.  Look upwards towards the eaves of buildings, at mid level around airbricks and entry points around window frames and where pipes enter buildings.  If the flight path leads towards your garden or in to the open, don’t forget to look down! Many common wasp nests are in the ground, in tree stumps, under piles of wood etc.

An indication that you’ve found a wasp nest will be when you see the wasps entering and leaving a particular place.  Or even the nest itself.  Often you may think you have a wasp nest in a bush outside or in a particular tree in your garden.  Make sure the wasps are definitely going in and out of the area.  Sometimes these wasps may have taken a liking to a particular plant or tree.  This is often because there is a rich source of insects for them there, most likely green fly or black fly.  If you look closely there might be lots of fly’s and sap on the branches.  The wasp nest is likely to be elsewhere.

Take a look at any lavender plant to see a whole host of Wasp’s, bee’s and flies.

Why are wasps pests?
In many instances the real or potential risk of stings and the annoyance caused by wasps will result in requests for destruction.  Wasps can inflict a painful sting, a habit that increases as the insects become more irritable with the onset of cooler weather, and the in gestation of fermenting over ripe fruits.

In most cases the sting is no more than unpleasant although multiple stings and those in sensitive places such as the head region or inside the mouth may be more serious.  In rare cases even a single sting may induce a condition known as anaphylactic shock (an extreme reaction to the toxins in the wasps venom).  With out medical attention it can result in death in a short space of time.  This only occurs in very few hypersensitive individuals.  It is important to avoid being stung and to be aware if your reaction to stings becomes more acute, medical advice should be sought.