Most people are not thrilled when they think about parasites. With images of leeches, ticks and mosquitos coming to mind. However, not all parasites are bad for us. A large group of parasites are quite beneficial to us. The critters I am speaking of are parasitic wasps. Not only are they useful to us in containing the number of pest insects, they are also incredibly beautiful (see the picture below).
It is this beauty that motivated the photographer Edwin Brosens, to start cataloguing all the species of parasitic wasps that he could find. More specifically, with the support of Cees van Achterberg and Kees Zwakhals of the Naturalis Biodiversity Centre in Leiden, the Netherlands, he aims to catalogue all the species of parasitic wasps in a national park in Belgium called ‘de Kooldries’.
The lifecycle of parasitic wasps
The lifecycles of different species of parasitic wasps can vary greatly. However, they all have in common that some stage of another arthropod (insects, spiders etc.) is parasitized. The wasp will locate its victim, for example a caterpillar (see the picture below). In this caterpillar the wasp will lay eggs. These will hatch into larvae, eat the victim from the inside out and crawl out again. There they will pupate to emerge later as adult wasps again.
Sounds easy enough, doesn’t it? Unfortunately it isn’t always that easy. There are lots of very cool and interesting aspects of the life of parasitic wasps worthy of attention. For one, the eggs have to overcome the immune system of the caterpillar and many wasps use viruses to do that. Others lay their eggs on the outside of their prey, the hatched larvae will dig their way into the host when they hatch. Furthermore, the tiny eggs of several wasps species can actually extract nutrients from the host using a sort of placenta. Even the parasitic wasps aren’t safe from parasitization! Some parasitic wasps are parasitized by other parasitic wasps and this is called hyperparasitization. In time we will write more about these intriguing aspects of the life of parasitic wasps.
So check the gallery for the beautiful parasitic wasps present in the Kooldries and keep track of this page for new photos and new stories!