Data from: Linking landscape structure, floral resource distribution, pollen use, and movement distances of a generalist predator

Understanding the habitat use and movement patterns of natural enemies in
agricultural landscapes is essential for enhancing biological pest
control. Since many natural enemies rely on floral resources, the
distribution of these resources in combination with movement behaviour
likely influence biological control in field crops. Nevertheless, few
studies have assessed natural enemy movement at the landscape scale. Here
we estimated minimal movement distances of the green lacewing Chrysoperla
carnea based on consumed pollen and the spatial distribution of the
respective plant species in 24 agricultural landscapes (500 m radius).
Lacewings were sampled using sticky traps in the centre of each landscape,
and the consumed pollen were identified. The location of the most
important pollen-providing plants was mapped in each landscape. Distances
to potential sources of pollen consumed by 346 lacewings were used to
derive minimal movement distances. Lacewings consumed mostly pollen from
insect-pollinated plants that were present within 500 m from the sampling
location. The distance to the nearest source of consumed pollen exceeded
200 m in 31% of lacewing individuals, demonstrating the relevance of the
landscape scale to understand their population dynamics. Distances were
shorter to insect-pollinated than to wind-pollinated plants, and shorter
early than late in the season. Mean and median distances to pollen sources
were negatively associated to flower availability and edge density in the
landscape, but this was not the case for minimal distances. Synthesis and
applications: Our findings suggest that the spatial distribution of
flowering wild plants can inform movement patterns of lacewings and other
flower-visiting insects in agricultural landscapes. In addition, the
location of floral resources in the landscape is important for its
capacity to sustain natural enemies. Given the strong reliance of
lacewings on pollen from nearby insect pollinated woody plants, the
promotion of native shrubs and trees, such as Prunus, Salix and Castanea,
should be prioritised for natural enemy enhancement in agricultural
landscapes. Doing this in the form of hedgerows or agroforestry systems
would lead to only minimal reduction in production areas, and provide
additional benefits such as biodiversity conservation.