Auroras and Migrating Birds
Do great auroral displays affect migrating birds? It now seems that there is some connection, though how it comes about is obscure. The most spectacular auroras occur during intervals known as magnetic storms; during these times it appears that migrating birds shift from their normal tracks.
There is a hint that migrating birds have a tendency to fly left of normal track during magnetic (and aurora!) disturbances.
More obvious is an observed variation in migrating track direction as much as twenty or thirty degrees to either side of normal during disturbances.
According to an article by Frank R. Moore of Clemson University that appeared in the May 6, 1977 issue of Science, these effects have been seen in migrating robins, warblers and other passerine (perching) birds. Tests with homing pigeons also show that birds may sense change in the earth's magnetic field. So far, there is evidently no proof that birds actually use the magnetic field for navigation.
If, as suggested, migrating birds move in more variable directions when experiencing magnetic field changes, one wonders what happens to them when they reach the auroral zone. It is here that the magnetic field varies the most and most rapidly. Could it be that the magnetic disturbance accompanying the aurora tends to disperse birds east and west along the auroral zone and thus affect where they do their summer nesting?
