Data for: Combining radio-telemetry and radar measurements to test optimal foraging in an aerial insectivore bird

Optimal foraging theory posits that foragers adjust their movements based on prey abundance to optimize food intake. While extensively studied in terrestrial and marine environments, aerial foraging has remained relatively unexplored due to technological limitations. This study, uniquely combining BirdScan-MR1 radar and the ATLAS biotelemetry system, investigates the foraging dynamics of Little Swifts (Apus affinis) in response to insect movements over Israel's Hula Valley. Insect Movement Traffic Rate (MoTR) substantially varied across days, strongly influencing swift movement. On days with high MoTR, swifts exhibited reduced flight distance, increased colony visit rate, and earlier arrivals at the breeding colony, reflecting a dynamic response to prey availability. However, no significant effects were observed in total foraging duration, flight speed, or daily route length. Notably, as insect abundance increased, inter-individual distances decreased. These findings suggest that Little..., Bird movement data was collected using the ATLAS telemetry system. Insect data was collected using an insect radar., , # Data for: Combining radio-telemetry and radar measurements to test optimal foraging in an aerial insectivore bird

[https://doi.org/10.5061/dryad.xwdbrv1qh](https://doi.org/10.5061/dryad.xwdbrv1qh)

## Description of the data and file structure

Little swift (Apus affinis) movement data collected using the ATLAS system. Column headers are descriptive and contain units.Â