[jamest (OP)]

Rick from Canada, home of the Canada Goose, with the next question:
'With the fall season upon us, the geese are taking flight, getting ready to migrate. When flying in their 'V' shaped formation. they are almost constantly honking.  I am wondering just what the value of this honking might be. It obviously involves some expenditure of energy, but I don't see that they are in danger from predators or at great risk of losing the rest of the flock?'

[alancalverd]

Formation flying is difficult enough when all the aircraft are similar and flying well below their limits, but birds have differing strengths, so the lead changes frequently and the weaker ones want to fly around halfway along each arm of the V so they get the advantage of the leaders' slipstream but don't get left behind, as might happen at the end of the V. And just because the strongest or freshest is in the lead, it doesn't follow that he actually knows the way, or where the best rest stops might be - the older and weaker guys may be better navigators. 

Hence although human pilots generally maintain radio silence during a formation cruise, geese and their ilk do a lot of chatting. 

[Billy Fisher]

I?ve always thought the honking was their way of keeping the group together and organized. From what I?ve read and seen, it helps them stay in sync while flying in that V-formation, which is super efficient for cutting down wind resistance. It?s kind of like them saying, ?I?m here, keep going!? Especially in bad weather or when visibility?s low, it probably makes sure no one drifts off. It?s pretty fascinating to watch, honestly.