These birds can sense Earths extremely weak magnetic field sort of like they had a compass inside their brains during their travels between Eastern Europe and Northern Africa
या पक्ष्यांना पूर्व युरोपातून उत्तर आफ्रिकेत प्रवास करत असताना पृथ्वीच्या (अत्यंत क्षीण) चुंबकीय क्षेत्राची जाणीव असते.