Monday, 1 August 2016

Wasps: amazing creatures, not a menace!

First of all, a little update on recent happenings. A few weeks ago it was my birthday, and I became 14 years old. It was quite odd, as somehow being 14 seems a lot more like being a teenager than being 13 does! I had a really good day though, and the next week, I met up with my friends, slept in a hammock in the woods, and went boating on a river! My friend, Eden, spotted a pair of grass snakes, and later I spotted a kingfisher darting away upriver.

The mystery bone that I talked about here has not yet been identified. I have asked around on Twitter, and although people have been very helpful, as to yet I have no definite answer. My thanks to those giving me advice though!

Now, onto the subject of this blog post. You may remember that I recently talked about the wasp nest which my dad and I found in our shed (see the post here). Well, the nest is still going strong, and is increasing steadily in size! It has now doubled in size since the first time I talked about it on the 23 June (the date that I write this on is the 1 August). The activity around the nest is also increasing - it is becoming slightly nerve-wracking to enter the shed with the whirlwind of wasps coming out of the nest.

 The wasp nest in June. It has now been mended by the wasps, who have also been busy with home expansion: the nest is now approaching the size of a pumpkin!

As my parents asked questions about the wasps, I realised that my knowledge of wasps is very low, so I wanted to find out some more information. Here's some questions that I had, and the answers that I have found:

 What happens to wasps in the winter?
The whole nest dies! Yes, after all the hard work during the rest of the year to build the nest, the workers all die and the nest will never be used again! The lack of food kills the wasps off, but this is completely normal, and a natural part of the insect's life cycle.
However, not all of the colony dies. The young queens live on, and will hibernate during the winter months. They do not do this is in a nest, instead they will find a sheltered place to hibernate. Many people think that a particularly cold winter is bad for wasps because it will kill the queen. This is a myth: the queen is actually perfectly safe from cold temperatures in her peaceful state of hibernation. In fact, a particularly mild winter is bad for wasps - it means that the queen awakens early, but because there is no nectar for her to eat, she dies.

What happens next to the queen?
As spring arrives, the queen will emerge from hibernation. She has 2 things on her mind: food, and making a new nest. Once she has found a suitable place to make her nest, she will begin building. She uses her mandibles to scrape up wood and chew it into a pulp, before building a new layer of her nest with it. She will lay her eggs in the nest to keep them safe, and once they emerge into grubs, she will undergo a change in behaviour. Until now she has been a nectar-feeder, a valuable pollinator to flowers. This stops once her eggs hatch. She will stop foraging altogether, instead living off the sugars which can be found in insect exoskeletons (more on that later). But what caused the queen to stop foraging? Well, the amount of work she's doing! During the early days of her nest, she is so busy that she simply has no time for feeding herself. This is because, as well as expanding the nest and collecting wood, she must also begin hunting insects. She does not eat them herself, but instead give them to her grubs, who need more protein than what can be found in nectar.
The strangest part is yet to come, however. So far the vision of an attentive mother feeding her babies has been fairly normal. But as the larvae munch away on their insect food, they convert the exoskeletons of their food into sugars, which they then feed to the queen! The mother is not only feeding her offspring, but her offspring are feeding her!
The grubs' chores don't end there, though. When the queen returns to the nest with a mouthful of wood, she will give it to the larvae, which will quickly chew it up for her, mixing it with their saliva to form the pulp used to layer onto the nest. The grubs can do this job much quicker than the queen could.

How does the nest progress after that?
The larvae pupate and become adult workers, and take over nest care duties. This gives the overworked queen a nice rest - well, almost. From now on she has a fairly easy life, simply lying in the nest and laying more eggs to increase the colony.

Are there different categories of workers?
The workers are divided into different duties:
. some wasps look after the queen, feeding her and tending to any other needs that she may have
. other wasps act as guards, protecting the nest from intruders.
. young workers have the cleaning duties, removing waste material from the nest.
. some wasps will collect water droplets, then deposit them on the outside of the nest. This is not for drinking purposes, it is actually to cool the nest.
. another caste of workers will sit outside the nest, with the unusual job of simply fanning the water. This causes it to evaporate, taking heat with it, further aiding the cooling of the nest.
. some workers will collect wood to be used in expanding the nest,
. yet another caste of workers will do the hunting: catching insects to feed to the grubs. Remember how the larvae used to feed the queen? Well, the new workers have exactly the same problem as the queen did, they're just too busy to find nectar to feed on. Instead, as before, the grubs will produce sugars to feed the workers with.
. some workers are on hand to help adult wasps emerge from their cocoons.

How do wasps reproduce?
There comes a time when the queen may chose to make special wasps. She can chose whether to lay a female egg or a male egg - the fertilized eggs form females, the unfertilized ones form males (called drones). Sometimes she will create a special female: a young queen. Exactly how she does this is unknown but it is thought that she may feed the grub a special pheromone. Because all of the queen's workers are infertile females, the drones and queens are special in that they can reproduce.
Once the drones and young queens have become adult wasps, they will emerge from the nest and produce what is known as a mating swarm. After she has mated, a young queen will not go back to the old nest, instead she will go off to a sheltered place to hibernate. And thus we are back where we started.

What happens to the old nest after this?
The queen will stop producing eggs, and she will eventually die. This has an effect on the workers, because without larvae being produced, they cannot get the sugary snack that they previously got from the grubs. Instead, they are forced to forage for themselves, being attracted to anything sugary. They will feed on fruit, nectar, and anything else they can find which is sugary. It is during this time of the year, in the autumn, that these hungry workers can sometimes be found trying to eat our food. Once the weather gets colder, and there is no nectar or fruit to feed on, the workers will die, along with the old queen.

So, there you go. If you dislike wasps, then perhaps after reading this you will at least admire them as a wonder of the natural world, and not just annoying little things which will try and eat your jam sandwhiches and sting you!

Until next time, keep on the wild side!

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