Pallid swifts are close relatives of common swifts, wintering in West Africa and breeding around the Mediterranean and southern Europe. Their long-distance migrations involve extraordinary physiological demands.
Pallid swift welfare during migration and breeding involves extraordinary energetic demands that leave little buffer for food scarcity. Episodes of cold wet weather that suppress aerial insect flight cause rapid energy depletion, particularly for breeding adults provisioning chicks. Loss of traditional building nest sites through modern renovation forces pairs into suboptimal locations. Swift boxes and legislative protection for active nest sites maintain nesting opportunities.