Station: [5] Wasps – Master Builders of the Insect World

Wasps! Terrifying to some people, a nuisance at least to most.

When we talk about wasps, we generally mean social wasps that live in communities of varying sizes. They include the hornet, which is the largest of our wasps here in this region. Hornets establish their nests in all kinds of cavities: be it in an old tree, in a nesting box or even in an attic. Some wasps even move into burrows previously inhabited by mice.

As with all insects, the intelligence of a single individual is limited, but by working cooperatively, wasps build nests to raise their offspring that are truely masterpieces of insulation and ventilation technology.

The nest consists of a paper-like substance made of wood, shredded by the wasps' strong jaws and mixed with their saliva. This mixture rapidly dries when exposed to the air and becomes rather like paper. The fascinating grain you see on the nests is due to different types of wood being shredded in this way.

In spring, the queen starts building the nest with a few cells suspended from a short cone. It’s a lot of work for a single insect! Subsequent generations of workers then take over and expand the nest. They build it in terraces, tier by tier, with layers of cells separated by short columns.

The outer cover is built up in several layers around the actual cells. Some wasp species even afford themselves the luxury of a landing board by adding a ramp-like extension to the entrance area.

The gaps filled with air provide excellent insulation for the nest. Ventilation shafts ensure an exchange of air within the structure. If the sun is on the nest and it grows too warm, workers are assigned to ventilation duty. They fan fresh air into the structure with their wings. Others fetch water to regulate the temperature by evaporative cooling.

If it’s too cold, the wasps turn on the “heating” by vibrating their wings to generate warmth. This allows them to maintain the climate within the optimal temperature range for themselves and their brood – about 30 degrees Celsius.

If you’d like to see a short film of a hornet carrying out ventilation duties, please select "video" at the top left of your screen.