Wasps have a bad rep, but they deserve better. Like bees, they’re incredibly important to ecosystems.
They are “workhorses,” decomposers, pollinators and natural pest control agents. Here’s why we need wasps—and how you can support them by planting flowers that they love. (Image credit: wikimedia)
Pollination
Wasp control is voracious predators of insects like greenfly, but also act as valuable pollinators, transferring pollen from one plant to another as they visit flowers to drink their sweet nectar. In fact, a world without wasps would likely be a less fertile place.
But the ecological services that wasps provide are not as well understood as those of bees. Perhaps this is because, compared to bees, wasps have more of a negative public image; they are often perceived as nuisance pests. And because people tend to be reluctant to take part in a project that involves getting stung, it’s difficult for wasp research to gain traction.
Like bees, wasps live in colonies and have a queen figurehead. Each year, after hibernating over the winter, she starts nest building, laying eggs in cells which then turn into worker wasps. The wasp workers toil ceaselessly to build the nest, gather food and protect their queen. They are responsible for feeding the larvae and defending the colony, and they’re often seen hovering around homes and gardens looking for potential food sources.
Insects are essential for healthy ecosystems, decomposing biomass and providing a crucial link between the plant and animal kingdoms. But if insect populations decline, the Earth’s biodiversity is in trouble. This is why wasps are so important, and it’s why we need to preserve their habitats, not spray them with chemicals.
Decomposing Biomass
Wasps help to decompose organic matter, which helps with the recycling of nutrients and the maintenance of healthy ecosystems. Solitary wasps also feed on dead insects, including bees, ants and caterpillars, and are thus an important food source for many other organisms.
Despite their positive ecological functions, wasps are often viewed as pests by humans. They compete with native insect populations, impacting biodiversity and ecosystem function. They are a nuisance to outdoor enthusiasts such as bush walkers, picnickers and cafe patrons due to their foraging behaviour, aggressive tendencies and concealed nests. They also predate on bees in managed apiaries and damage horticultural crops like grapes and stone fruits.
The UCL-led study found that common wasp species are valuable at sustainably managing crop pests, and could reduce the use of chemical pesticides. This is because they capture a broad range of Lepidoptera, and do not experience the typical setbacks that plague chemical control methods such as resistance in pest populations.
Sadly, the negative cultural stigma surrounding wasps has resulted in a low level of public interest in wasp research (Livingstone et al., 2018). Overturning this prejudice could be pivotal in encouraging the public to work with these facets of natural capital, rather than against them. With the declining numbers of all insects, a greater tolerance for wasps would be beneficial to our ecosystems as a whole.
Natural Pesticides
As apex predators, wasps are great at controlling populations of pests like flies, caterpillars, grasshoppers, aphids, cicadas and more that can gobble up crops. By regulating these insects, wasps help minimize crop damage and reduce the need for harmful pesticides. In addition, wasps provide us with a host of valuable ecosystem services. For example, their venom and saliva have antibiotic properties and yellowjacket wasp venom has shown promise in treating cancer.
In the case of crop protection, introducing native wasps to farmlands could be a more effective and less expensive alternative to chemical pesticides. In fact, a new study published in Proceedings of the Royal Society B found that common wasp species could be valuable at sustainably managing crop pests.
This UCL-led experimental study was the first controlled experiment in semi-natural conditions to test whether social wasps could be used as a natural method of insect control. It is hoped that this research can pave the way for future studies, including gene drive experiments in more realistic environments.
The researchers note that this approach may have the potential to increase food security in developing countries where over-reliance on pesticides is a growing concern. It also has the added benefit of reducing environmental damage caused by chemicals and creating a more resilient garden, vegetable or flower crop. In order to take advantage of this opportunity, gardeners can plant flowers such as Erigeron philadelphicus (Fleabane), Eupatorium perfoliatum (Boneset) and Zizia aurea (Golden Alexander) that attract native wasps.
Food Web
When you look around at all the flowers and plants that we enjoy, most of them are pollinated by a variety of insects including wasps. Researchers have found that wasps are a backup pollinator for about 950 species of plants, and can provide pollination in the absence of bees or other insect pollinators.
While many people associate wasps with nuisance stings, these insects are vital to the ecosystem and shouldn’t be treated as a pests. They have several positive impacts on the environment as decomposers, pollinators and predators of pests insects and other wildlife.
Some wasp species also help pest control and bed bugs and decrease the need for harsher pesticides. For example, the common wasp Vespula vulgaris and the German wasp Vespula germanica can be very useful in gardens, allotments and agriculture, as they prey on crop pests such as black fly and aphids. They can be especially beneficial in organic farming, where they are used to naturally manage pest populations without the use of chemical sprays.
Other wasp species, such as the mud dauber wasp Ampulex compressa, kill pest cockroaches by laying an egg inside each one. This egg hatches and then the larva eats the cockroach from the inside out, causing it to die. These wasps are a natural form of pest control, and can be beneficial in many areas of the world where cockroaches are an issue.
