Quantifying trade-offs between butterfly abundance and movement in the management of agricultural set-aside strips

1. Agri-environment schemes (AES) create small areas of habitat within agricultural landscapes to support biodiversity. Here, we study butterfly flight behaviour within linear AES features and examine whether differences in resource availability affect the speed, linearity or directionality of local movements, thereby affecting their contribution to landscape connectivity.

2. We surveyed butterflies within three basic (naturally regenerating) and three wildflower-sown linear field margin strips (0.09-0.15 ha) on a farm in North Yorkshire, UK, and mapped butterfly flight paths to quantify local displacement (movement speed), efficiency (linearity, turning angles), directionality (step orientation) and behaviour (time spent flying, nectaring).

3. Butterfly species richness was similar between margin types (estimated asymptotic species richness of 21.9 [CI: 15.0-77.7] for basic margins and 14.2 [CI: 14.0-18.7] for wildflower-sown margins), but abundance was 78% higher in wildflower-s...