Mansier’s research focuses on “natural enemies”: insects such as hoverflies, ladybirds, lacewings and parasitic wasps. These species are vital allies for farmers because they feed on common crop pests like aphids. But decades of agricultural intensification have created vast monocultures where essential resources – nectar, pollen, shelter and varied prey – are scarce or absent.

‘We often think of pest control as something we need to buy or apply, but nature already provides incredibly effective solutions – if we just give it the right conditions,’ says Mansier.

Habitat diversity is key

Mansier emphasises that these beneficial insects require different resources at different times of the year, and no single habitat meets all their needs. Instead, they rely on a combination of habitats – a principle known as landscape complementation.

‘Think of it as creating a year-round buffet for beneficial insects,’ says Mansier. ‘When resources are available continuously, natural enemies can survive, reproduce and keep pest populations down. When those resources disappear suddenly, the whole system breaks down.’

Flower strips – how to do them right

“Flower strips” are increasingly common across European agriculture, but their success varies widely. Flower strips are narrow, intentionally planted bands of flowering plants placed along the edges of crop fields. They form a semi-natural habitat designed to support beneficial insects. But Mansier’s review of 75 studies shows that many strips fail simply because they lack the right flowers or bloom at the wrong times. Tailored flower strips – those designed specifically to support natural enemies – performed far better.

‘It’s not enough to plant “something with flowers” and hope for the best,’ she says. ‘The choice of plant species matters enormously, especially for insects like hoverflies that can only use certain types of flowers.’

Hidden dynamics revealed

To better understand how habitats interact across agricultural landscapes, Mansier developed advanced population-dynamic models focused on hoverflies and aphids. Her simulations reveal that woody habitats are especially important, providing nectar and prey early and late in the season, when crops offer little.

She also shows that crop fields themselves can act as important sources of natural enemies, challenging the long-held assumption that only semi-natural habitats contribute meaningfully to pest control.

Another key insight is the importance of consistent management. Poorly timed mowing or harvesting can abruptly remove crucial resources, disrupting predator populations at pivotal moments. Adjusting mowing schedules or staggering management across fields can prevent these sudden resource gaps.

‘Farmers don’t need to overhaul their entire landscape,’ says Mansier. ‘Small, well-timed changes – like delaying a mowing operation by a few weeks – can make a huge difference to natural enemy survival.’

A more sustainable agricultural future

Mansier’s research provides a scientifically informed roadmap for building landscapes that help natural enemies thrive. By integrating woody vegetation, carefully designed flower strips and complementary crops, farmers can strengthen natural pest control, reduce pesticide dependence and support biodiversity.

‘Sustainable agriculture isn’t about going back to the past – it’s about using modern ecological understanding to farm smarter,’ Mansier says. ‘When we design landscapes that meet the needs of beneficial insects, we’re investing in resilient food systems for the long term.’