In message <09c601c3d17f$87fcf6a0$7604c518@gollum>, James Fischer <[log in to unmask]> writes >A long-term (and still ongoing) study on a reasonably large number of >hives at several apiaries by Dr. Wyatt Mangum of Virginia, USA was >said by Wyatt last summer to show that reinvasion (or "inter-colony >drift", if you will) IS the apparent primary means for spreading varroa >between hives. I think we are using the word re-invasion here in two ways. I understand it to mean a new invasion (large numbers) from other colonies, once you have reduced numbers by treatment (hence the "re" "and invasion"), either from robbing or absconding/breakup of overloaded colonies. This often happens in autumn, hence the idea of re-invasion and well defined by Peter as such. Drifting will tend to equalise mites between colonies in an apiary. -- James Kilty :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::