I'm not sure this is such a great idea.  It would be if you could guarantee
the weather etc.  but I imagine that when sailing such a long trip there
WILL BE events that you can't forsee.
 
During those times the ferrets will be a distraction, they will need their
normal care and you will worry how they are doing when you also need to be
totally focused on whatever is going on (weather, sail down, engine failure
whatever).  I'm not sure that makes this very safe for you or them and I
would hate to see you feel forced into some weird decision, like leaving
them in Greenland to be shipped or something.
 
Wouldn't it be better to kennel them somewhere till you get to Denmark and
have them shipped then?
 
Mary
 
P.S.  I hate to sound like the grim reaper here but make sure you leave
them to someone in case something happens - which we should all do anyway
 
"Animals are not brethren, they are not underlings; they are other
 nations, caught with ourselves in the net of life and time,"
 Henry Beston
[Posted in FML issue 3299]