I’m happy to announce that the {skytrackr} package is on its way to CRAN. The {skytrackr} R package provides a convenient template fitting methodology and a Bayesian based optimization approach to estimate locations from light profiles. In my research together with Lyndon Kearsley we’ve used geolocation by light extensively to track swifts (an example light profile, as recorded during a year by a micro-logger on the back of a swift, is shown below).
Yesterday (2025-04-25) evening around 21:30h we got confirmation of the first swift arrival at the colony in Melsele. This good news got even better when we noticed that this is one of several swifts monitored with high-tech PathTrack GPS loggers.
Noteworthy is that Lyndon‘s swift tracking program received a video monitoring upgrade this winter with the support of the city of Beveren/Melsele and Regionale Landschappen Schelde-Durme. This system is similar to the colony in Ghent.
Swifts optimize their flight behaviour to adapt to favourable night-time light conditions, driven by light-responsive and size-dependent vertical insect stratification and weather conditions.
A short list of ongoing and upcoming conferences for 2022
In contrast to the current paradigm, which centers on insect availability using vegetation as a proxy, we show that weather related concentration of insects at convergence zones is key to describe foraging behaviour of Pallid swifts during the non-breeding season.