[If You Want It Fixed - Fix It]

Doesn’t effect life? What about geese and other migratory birds? They’ll get as lost as my mother.

I hope Google is ready for Y200000000000000000K.

[RFEngineer]

“What about geese and other migratory birds? They’ll get as lost as my mother.”

We’ll get all the geese from the Southern Hemisphere, they’ll get all the Norther Hemisphere geese.

[CedarDave]

Doesn’t effect life? What about geese and other migratory birds? They’ll get as lost as my mother.

If the change takes on the order of hundreds of years, I suspect that the change is slow enough that new generations of birds adapt and return to their birthplace based on the magnetic declination at the time of their birth.

[gleeaikin]

As CD suggests, the young birds probably fix on the magnetism at the time of birth, just as some birds will fixate on the first thing they see when their eyes open. Also, just as you may need a map (magnetic signal) to get to some place you visited as a child, once you get close you will be able to recognize local features to reach your destination (rivers, mountains, etc.

Furthermore, if the north pole is shifting at the rate of 40 miles a year, then if a half circumfrance of the earth is around 12,000 miles, then a complete shift would take around 300 years. This is long enough for a lot of adaptation to take place, both of animate and inanimate earth objects/beings.