What do wasps eat? It's not what you think!

When you think of wasps, you might picture these buzzing insects hovering around your food during a late-summer picnic, trying to steal a sip of your sugary drink or a bite of your sandwich. But what do wasps actually eat? It turns out, that their diet is much more complex and surprising than most people realize.

Wasps are fascinating creatures, especially regarding their feeding habits. While we often see them as a nuisance, particularly during the late summer months, wasps play a crucial role in nature and have unique eating behaviours that vary throughout the year. In fact, adult wasps don't have the mouthparts needed to consume solid food at all! Let's dive deeper into what fuels these insects and why their diet changes with the seasons.

The Truth About Adult Wasp Diets

Adult wasps don't eat solid food. This might be one of the most surprising facts about them. Unlike other insects or animals that can chew and consume solids, wasps are limited by their anatomy. Their mandibles (or jaws) are used mainly for hunting, cutting, and carrying prey, not for eating solid food. Instead, adult wasps rely on liquid diets.

But where do they get this liquid food from? The answer lies in an unusual and fascinating relationship between adult wasps and their young larvae.

How Adult Wasps Feed: Larvae as the Food Source

During the summer months, when wasp colonies are most active, adult wasps spend much of their time hunting insects. They catch prey, such as flies, caterpillars, and spiders, which they return to the nest. However, this isn't food for the adult wasps themselves – instead, it's food for their young larvae.

The larvae digest these insects and then excrete a high-quality sugar solution. This solution is created from the protein chitin found in the exoskeletons of the insects they consume. The adult wasps feed on this sugary liquid, making the larvae essentially a living food factory for the colony.

This exchange forms a critical part of the wasp's social structure, as adult wasps rely on their larvae for sustenance during the height of summer. As long as plenty of larvae are in the nest, adult wasps can feed from this rich sugar solution.

Why Wasps Turn to Flowers in Spring and Autumn

In early spring, before the colony's larvae are fully developed, and in late autumn, when there are fewer larvae left in the nest, adult wasps must find alternative food sources. This is when wasps are commonly seen feeding on nectar-producing plants.

In spring, adult wasps rely heavily on flowers for nectar, which provides them with the energy they need to build and maintain the nest. Without the sugar solution from the larvae, nectar becomes their main source of nourishment. Ivy, in particular, is an important late-autumn food source for wasps, as it flowers when other plants have stopped blooming. Certain trees, such as lime trees, are also favourites.

Late Summer and Autumn: Why Wasps Bother Us

By late summer and autumn, wasps become more noticeable in our lives, especially in outdoor spaces like gardens and parks. But why does this happen?

As the larvae begin to mature and the colony's life cycle starts to wind down, there are fewer larvae to provide adult wasps with their sugar solution. As a result, wasps begin to search for alternative sources of sugar. This is why they often hover around soft drinks, fruit, and other sugary foods during the late summer months.

This behaviour, known as "sweet feeding" , is driven by the wasps' need to find quick energy sources. Unfortunately, this also makes them a nuisance in outdoor areas where people gather, like pub gardens, picnics, and barbecues. As the season progresses, food quality diminishes, and eventually, the food source becomes so poor that the wasps starve.

The Vital Role Wasps Play

While viewing wasps as annoying pests can be easy, they are vital to the ecosystem. Wasps are predators that help control the population of other insects, including many pests that damage crops. Without wasps, the balance of insect populations would be disrupted, leading to potential agricultural issues.

So, while wasps may bother us during certain times of the year, it's important to remember that they are a crucial part of the natural world, with a diet and lifecycle supporting their colonies and the ecosystems around them.