The VCF has prepared a new protocol with guidelines on the best practice to bleach bearded vulture feathers. This document – which for the moment is only available in German, but will be translated into English soon- was developed because the official list of common marking methods for wildlife in Switzerland is under revision and a reference for bleaching feathers was needed.
Bleaching flight and/or tail feathers is a very useful method to mark birds for individual recognition (see photo)– all the released bearded vultures in our three reintroduction projects (Alps, Massif Central-Grands Causses and Andalusia) do have some feathers bleached, following an individual combination. The birds loose these feathers at some point in their moult, but sometimes these outlive the lifespan of the satellite tag and allow for the bird to be identified when flying around.
Having individual sightings of birds is crucial for us to estimate mortality and survival.
You can download the document (in German) below.