In article , Martin
writes
The parasite is only one cause.

If you google you will find that it has been identified as the main
cause.

But if you talk to bee experts (and many bee keepers) you get a
different picture from google.

It seems most likely that varroa itself wouldn't cause anything like the
problems that have been seen. However, bad infestations can weaken a
hive to the extent that other environmental factors (that also in
themselves wouldn't cause collapse) can tip colonies over the edge to
collapse.

It really is fascinating stuff (as are bee colonies in general).

--
regards andyw