nostr:npub1cp9vlynjc03j2lda8z7mn4a4vf66us8xnlk32f3uecx90d6yfh0sf3mkgc magnetic ability seemed to be a big part but it was inconclusive whether that was the only way finding ability used for homing—I remember another study that showed they could still make their way with changing fields, but more reading required!