Pollen on feathers: unlocking the potential to study avian life histories through palynology

Capsule: Bird-associated pollen can be effectively retrieved from single-use gloves worn during ringing to reveal patterns in habitat use and migratory ecology. Aims: To compare abundance and richness of bird-associated pollen retrieved from ringer’s gloves, bird bags, feather swabs and clippings from Pied Flycatchers (Ficedula hypoleuca) to establish optimal methods for avian palynological research; also, to highlight real-world applicability though proof-of-concept analysis. Methods: 30 females from three sites were handled during routine ringing using new cotton gloves and bird bags; feathers were swabbed and clipped under licence endorsement. Pollen was retrieved, identified and counted. Results: More pollen (number of grains; greater richness) was retrieved from gloves; bags were also effective but other methods were poor. Most pollen was from taxa found at the breeding ground, both arboreal and non-arboreal. Non-breeding ground pollen (all arboreal) was sympatric with Pied Flycatcher wintering areas in West Africa and/or migratory routes. There were differences in both UK and non-UK pollen assemblages and between breeding sites, demonstrating value of the approach for studying habitat and migratory connectivity. Conclusion: Feathers are a rich source of pollen that can be quantified non-invasively by analysing ringer’s gloves or bird bags, which has wide applicability both taxonomically and geographically.