Loyal visitors of our GPS tag portal have already noticed: recent points of the ‘red animal’, Hellegatsplaten 2019 are missing. After the GPS logger of this white-tailed eagle collected great data for almost a year, it became quiet, and we have not received any signals since 22 May by the logger.
We are thinking of two possible scenarios: the logger has a technical defect, but the eagle is alive and well. Or the logger was damaged, for example by a collision with a train, or a collision with a wind turbine, which also killed the eagle.
Determining which of these scenarios is correct is more difficult than it seems. First, the COVID-19 regulations made it difficult to visit the last known location. And because the data is sent twice a day in a bulk message, the last known location is probably not the last actual location of the animal, which makes is hard to search for a death animal. In any case, the manufacturer did not receive logger sending attempts.
The last message with locations came from around Hamburg, and the local working groups and bird watchers in Germany keep their eyes open for eagles with transmitters and a GPS logger. However, the birds with loggers that have been reported so far were not the bird of the Hellegatsplaten 2019. Also, the white tailed eagle has not been reported via the networks that collect dead animals in the Netherlands and Germany for post mortem research.
So, if you observe radio-tagged white-tailed eagles, please let us know!
Zeearend Nederland working group & Wageningen Environmental Research