Much-maligned wasps do us a world of good

Wasps, widely viewed as the evil cousins of beloved honeybees, tend to get a bad rep. We often see wasps as pests that can spoil outdoor picnics by hovering constantly around treats and stinging in anger when we try to whisk them away.

That commonly held view needs a major revision.

Not only are wasps not pests but they are just as valuable as bees and other “useful” insects for the environment, say scientists who have found that aculeate wasps provide key ecosystem services. The much-maligned insects serve as predators, act as pollinators and help disperse seeds, among other useful functions.

Whether they are solitary or social, aculeate (stinging) wasps “offer substantial, but largely overlooked, economic benefits through their roles in natural pest management and biological control programs,” a team of scientists from University College London and the University of East Anglia explains in a study.

The researchers have reached this conclusion after examining more than 500 academic papers to see how the 33,000 or so species of stinging wasps worldwide contribute to their ecosystems and benefit people in turn.

“Wasps are one of those insects we love to hate — and yet bees, which also sting, are prized for pollinating our crops and making honey,” says Prof. Seirian Sumner, a scientist at UCL’s Centre for Biodiversity & Environment Research, who adds that we mostly hate wasps because we don’t understand their key role in ecosystems.

“[W]asps could be just as valuable as other beloved insects like bees, if only we gave them more of a chance,” Sumner emphasizes.

Wasps prey on other insects, which means they serve as a means of natural biocontrol to protect crops. That service alone is worth at least $416 billion a year around the planet in agriculture because wasps regulate populations of arthropods, like aphids and caterpillars that feed on crops.

“Solitary wasp species tend to be specialists, which may be suited to managing a specific pest, while social wasps are generalist predators, and may be especially useful as a local source of control for a range of crop-eating pests,” the researchers explain.

By enlisting wasps for pest control, especially in tropical countries, farmers can protect high-value crops, such as maize and sugarcane in Brazil.

“The value of wasps in supporting our crops remains poorly understood; we hope that by rehabilitating their bad reputation, we can collectively get the most value out of these fascinating creatures,” says Alessandro Cini, a scientist who coauthored the paper.

And there is more.

Wasps also act as pollinators, contributing more than $250 billion a year worldwide to the economy, the scientists say. Based on previous research, Sumner and his team estimate that various species of wasp visit as many as 960 species of plant, including 164 species of plant like certain orchids that wholly depend on wasps for pollination. In fact, orchids have evolved to look like the back end of a female wasp to attract males.

In addition, wasps can also aid us in developing new medications as their venom and saliva have antibiotic properties. The venom of yellowjacket wasps may result in a treatment for cancer.

However, just like a myriad of other insects, wasps are losing their habitat and falling victim to climate change and large-scale pesticide use. Thus, efforts to protect them are vital, the scientists stress.

“[T]here is urgent need to address their conservation and ensure that habitats continue to benefit from the far-reaching ecosystem services that wasps provide,” says Ryan Brock, a researcher at the University of East Anglia.