Wasps & Hornets
What Purpose do Wasps Serve?
Very often people ask us what purpose do wasps serve?
In early summer wasps, like bees, pollinate plants and flowers as they feed on nectar. If we were to eradicate all wasps it would cause more problems than it would solve. So, wasps do serve a purpose and despite being a problem at certain times of the year, they are a beneficial insect. So in the natural world, wasps although irritating to humans, have their role to play.
Wasps and hornets are predatory insects and spend a lot of their time hunting and catching smaller insects to feed to their larvae (young wasp grubs). The insect prey is killed by the adult wasps and chewed up into small food packages and taken back to the nest. These food parcels are then fed to the young wasp larvae which turn the exoskeletons (chitin) of these prey insects into a sugary solution which they feed back to the adult wasps.
It is difficult to guess the exact numbers of insects which are killed by a single wasp colony through the course of a summer. It has been suggested that a single wasp nest will catch approx 5 metric tons of insects in one year. Whilst we are not entirely convinced of that number whatever it actually is, it will be substantial.
Which wasps are a nuisance?
As pest controllers we are mainly called to deal with three types of social wasps which form colonies. There are many other types of wasps in the UK, but these are mainly solitary wasps.
The main nuisance wasps are:
The common wasp (Vespa Vulgaris)
How can we identify a common wasp?
Face view of common wasp, notice the anchor marking.
Looking at the abdomen of a common wasp:
The European wasp (Vespa Germanica)
Face view of a European wasp, notice the three dots instead of the anchor.
Looking at the abdomen of a European wasp:
The Hornet (Vespa Crabro)
The hornet is noticeably bigger than your average wasp and can be an inch or more in length. They tend to have more red colouring.
Face view of the hornet.
Looking at the abdomen of a Hornet:
Just to throw an unknown into the mix, can you guess what it is yet?
The Median wasp.
This is a social wasp like the common or European wasp, but most years it is normally out competed by the other species.
Are Hornets a wasp?
Hornets although much larger than normal wasps, are themselves classed as wasps (order: Hymenoptera). They are predatory insects in the same way as normal wasps but predate on larger insects. In fact they will attack a normal wasp nest and kill the adult wasps. They then raid the nest and take the wasp larvae back to their own nest as a food source for their young.
Hornets are also known to attack honey bee hives for the same purpose, although honey bees do have a defence against single hornet attacks which surprisingly is that honey bees can survive a higher temperature than hornets.
When a predatory hornet is detected in a honey bee hive, the bees will attack the intruder and "ball" it (they swarm around the hornet). Then using the muscles in their bodies to produce heat, they raise the temperature higher than the hornet can withstand; in essence cooking it alive.
The hornet nest, although large in size, doesn’t hold as many individuals as a common wasp nest; normally only 300 or so individuals.
What is the difference between wasps, bees and hornets?
Wasps and hornets differ to bees in several ways. For example they do not use nectar to make honey in the same way as bees do. They are not active throughout the entire year like bees and although wasps will swarm feed, they do not swarm in the same fashion as honey bees.
Honey bees differ from wasps & hornets by staying active all year round and storing food (honey) in the nest or hive. Managed honey bees are often fed supplementary food during the winter by the bee keepers.
At the end of the wasp season, in the autumn, a wasp or hornet nest will produce new queens and males. Once these hatch out, they leave the nest to mate. When this has taken place the males die off and the now fertilised queens find somewhere to hibernate through the winter (often in loft spaces or garden sheds).
In the spring, these queens emerge from hibernation and find somewhere to start a brand new nest.
The Honey Bee
Although wasps, hornets and honey bees appear similar in appearance, bumble bees are completely different and appear furry.