Busy Sand Martins (Riparia riparia)

A colony of very busy Sand Martins, seen in a nature reserve (Auenschutzpark "Chly Rhy") near Rietheim / Bad Zurzach in northern Switzerland. The Sand Martin (Riparia riparia) or European Sand Martin, Bank Swallow in the Americas, and Collared Sand Martin in India, is a migratory passerine bird in the swallow family. Thank you for your visits / comments / faves!