BlueGreen Labs (with Lyndon Kearsley as lead and Koen Hufkens co-lead and data scientist) is proud to be lead author on a recent study on Pallid swift foraging behaviour. In our research we investigated the flight behaviour of pallid swifts Apus pallidus, a small aerial insectivore, in relation to non-breeding season atmospheric conditions using state-of-the-art GPS logged data.
Our analysis shows two novel diurnal flight patterns which suggest that pallid swift prey on insects concentrated along frontal convergence zones, in particular the continental Inter-Tropical Convergence Zone (ITCZ) and a coastal sea-breeze front (see figure below). Resource use seems not only contingent on the abundance of insects, but also favourable atmospheric conditions.
Persistence of swifts in wintering feeding grounds might therefore depend on the prevailing atmospheric conditions and their concentrating effects on insects rather than solely the vegetation state and co-dependent insect populations. Migration events within, to and from, the non-breeding season foraging locations might not only be guided by a decline in vegetation as common metric for prey availability, but also by shifting wind directions and their concentrating effects.
We are grateful to all co-authors as this has been a true collaborative effort bringing together a wide range of expertise into one manuscript. You find links to both the open access PDF and online article can be found on the manuscript page.