JNS
A University of Haifa study uncovers unexpected differences in the migration paths of similar species of the birds.
A new University of Haifa study published in the Journal of Ornithology has documented, for the first time, the full migration routes of Common Swifts, Pallid Swifts and Alpine Swifts that nest in Israel—showing that the seemingly similar species followed dramatically different paths, schedules and distances on their journeys to Africa.
The research team, led by Professor Nir Sapir, along with doctoral students Itai Bloch and Daniel Bloch, and Dr. Christoph Meier of the Swiss Ornithological Institute, tracked the birds by using miniature light-level geolocators attached during the 2017–2020 nesting seasons in Ramat Gan, Mount Sodom and Haifa.
When the birds returned a year later, the devices revealed the full annual migration cycle of 10 Common Swifts, 10 Pallid Swifts and five Alpine Swifts.
Swifts, which spend nearly their entire lives in the air—eating, sleeping and even mating while flying—have long intrigued scientists. While some European routes were previously mapped, migration from the eastern Mediterranean remained largely unknown. They typically stay in Israel for about 100 days, arriving in February and leaving in early August, after their nestlings have fledged, to return to Africa.
The study found that Common Swifts traveled the farthest—about 15,000 kilometers per year—and spent around 60 percent of the year in sub-Saharan Africa.
Pallid Swifts migrated intermediate distances of roughly 10,000 kilometers and showed a previously undocumented pattern: crossing the Sahel from west to east in winter and lingering up to two months along the Red Sea during spring migration.
Alpine Swifts migrated the least, only about 5,700 kilometers annually, spending about 73 percent of the year in Israel and wintering in a limited region of the Nile Valley.
The findings revealed notable differences in migration speed and timing. Common Swifts returned more quickly in spring, Pallid Swifts slowed down due to their Red Sea stopover, and Alpine Swifts maintained a direct and consistent route without long breaks.
“These diverse patterns underscore the remarkable ecological flexibility and unique adaptations of each species to its environment and climatic conditions,” the researchers concluded.
“They also show how environmental changes may affect each species differently. The ability to track individual birds across their full annual cycle provides critical insight into the links between environmental conditions, climate and bird migration," they added.
