摘要:A leading cause of managed honey bee colony mortality in the US,
Varroa destructor populations typically exceed damaging levels in the fall. One explanation for rapid population increases is migration of mite carrying bees between colonies. Here, the degree to which bees from high and low mite donor colonies move between apiaries, and the effect visitation has on
Varroa populations was monitored. More bees from low mite colonies (n = 37) were detected in receiver apiaries than bees from high mite colonies (n = 10,
p <
0.001). Receiver colony
Varroa population growth was associated with visitation by non-natal bees (
p =
0.03), but not high mite bees alone (
p =
0.19). Finally, colonies lacking robbing screens experienced faster
Varroa population growth than screened neighbors (
p =
0.01). Results indicate visiting non-natal bees may vector mites to receiver colonies. These results do not support the current two leading theories regarding mite immigration – the “mite bomb” theory (bees from high mite colonies emigrating to collapsing colonies), or the “robbing” theory (natal robbing bees return home with mites from collapsing colonies). Potential host-parasite effects to bee behavior, as well as important management implications both for
Varroa treatment regimens and breeding
Varroa resistant bees are discussed.