Subject: [Tweeters] dispersal
Date: Aug 26 11:42:17 2009
From: Steven Mlodinow - sgmlod at aol.com



Greetings All



One last point, sorry.

I don't think that local movements of young birds would be considered dispersal. I mean, to take that to an extreme, leaving the nest for the next tree could be considered dispersal. I don't know exactly where the lines are drawn, but I think that the bird would have to leave its immediate environs.



A good example would be the uphill movement of Rufous Humms. I don't know whether this is considered part of their migration or a post-breeding dispersal/migration, but that is the magnitude of movement that I think is required for either dispersal or migration to be used.



Best Wishes

Steven Mlodinow